BIO120H1F 2018 (700+)

George Mendel

"Father of Genetics" studied hybrids using peas. Determined how traits were inherited.

Carl Linnaeus

"Father of Taxonomy"; established his classification of living things; famous for animal naming system of binomial nomenclature

Richard Goldschmidt

"Hopeful Monster" - a single mutation has a large effect in phenotype, "mutationist"

Theodore Dobzhansky

"nothing in biology makes sense except in the light of evolution," geneticist and evolutionary biologist, and a central figure in the field of evolutionary biology for his work in shaping the modern synthesis

solution of the differential-equation form of the logistic:

- (don't need to memorize equation, know the shape of the graph) - a population growing logistically will always make a direct and smooth approach to the carrying capacity, from any starting point other than N=0

heat balance

- Active vertebrates: generate heat from their internal metabolic functions - Most basic adaptation for controlling these balances concern size+shape of the animals Bergans rule is the driving factors some traits under mechanical constrat=int contradict these rules - same heat conservation advantages by growing larger can be achieved by insulation (energetically cheaper and evolutionary easier)

How environmental factor determine distribution and abundance

- All organisms have restricted spatial distributions - Can classify environmental factors: *Abiotic factors:non living *Biotic factor: living

Arctic vs alpine tundra

- Arctic tundra: one very long winter each year - tropical mountaintop: short winter every night and warm summer every day (rapid oscillation of heat and cold is a challenge for organisms) - hibernation + long-distance migration are solutions in the alpine - alpine environments expose organisms to extreme UV radiation (not a problem in the arctic

Tropical rainforest biome

- BIG WACTOR: WATER - Key factors: amount and seasonal timing of precipitation - Distinct wet and dry seasons bc advance recession of the intertropical convergence -ITCZ moves very little and just makes rain= rain forests or evergreen lowland forest(some rain is likely to fall every day) - Plants fitness depends on ability to compete for light nutrients - Canopy is higher than in most temperate forest - Interior is dark, intensely shady - Heavy rainfall= highly leached soils - enriched with aluminum and iron, soil is like redbricks especially when trees are cut down - Darker than temperate- more layers of leaves - Too little light doesn't allow dense growth in the understory (plants that do occur are specialists that extremely shade tolerant) - giant herbs that would quickly overheat if exposed to the sun - High NPP - Dense rainforest only occurs where canopy has been opened up by a fallen tree - Leaves are smooth and shiny, drip tip= retard establishment of epiphyll crust: ecological convergence - High elevated species diversity - high diversity in tropics to low diversity at higher altitudes

Alkaloids

- Beneficial pleasant in small doses, toxic in large quantities

Understanding fundamental behaviours of these models (look at spreadsheet

- Change the initial age structure (watch values of ¥, R_0, T; will they change also? what do these values depend on?) - Compare projection number (blue cells) to projection of proportions (lavender cells)-> go down the diagonal of the table of numbers, with passing of each year time + age increases - Note how actual increases in size from one time to the next is initially bumpy but later smooths out (start with n_0=100 newborns, note how all age classes represented and how their relative proportions become stable, age structure converges to a stable age distribution - change fecundity + survivorship schedules to achieve R_0=0 "zero population growth" (stable age distribution shifts with changes in population growth rate - how?)

The Gleason- Clemens debate

- Clement was majorly accepted by most votes - Gleason quit ecology - The argument wasn't settled by evidence - Gleason was right in the long run

Gleason's opinion

- Closely associated species are found together because they have similar ranges of tolerance to abiotic factors - Communities are open to those that can grow in their environment - Each species reacted individualistic to changing conditions - Community composition changes act as a smooth continuum not a series of discrete step - Plant association is a coincidence

Modeling population without limits: exponential and geometric growth

- Darwin realized all organisms have the potential reproductive ability to produce multiple offspring - Growing at a constant, greater- than- replacement rate leads to explosive growth Both density independent N+1 = N+¥

The boreal forest biome

- Dominated by evergreen coniferous trees - very extensive -"spruce moose" biome - cold temperatures, short summers - Unsuitable for agriculture - frequently chopped down for logging or disturbed by fires or windstorms. - extends southward in the mauntais; higher elevation = climatic conditions like those of higher latitudes - very dense forest -NPP reduces (short growing season of ess than 4 months + poor soils

Properties anticipating part 9

- Ecosystem properties - stability of species composition, - resilience in the face of stress or disturbance, - kinds of interactions that link species - how species exert selective pressures on each other - wether species might coevolve

Fire resistant trees

- Exist in fire savanna-like grasslands - have bark thick enough to protect sensitive cambial tissue from fire damage - bur oak, acacia, ponderosa pine, ecalypts

Hypothetical species in which probability of dying is constant across all ages

- Exponential decline with a constant half-life - curve (I_x vs x) declines steeply and gradually approaches 0 as an asymptote - called type II survivorship curve - plotting log I_X vs x = straight line with negative slope * straight lines - type II= straight * concave curves = Type III= concave - plants and animals * convex curves = type I = humans

The desert Biome

- Extreme physiological challenges - develop when conditions are too dry to support continuous cover of short grasses (xeric soils) - plants that persist are strong in competition for water - specialized adaptations that acquire water and to use it efficiently - substantial areas of unvegetated soil surface open up - soils is poor: sandy, gravelly with very little organic matter and little Nitrogen - hot or cold - plants very small, very slowly - transitory availability of water gives organisms something to fight over and hoard -plant growth more diverse than in shortgrass prairies (grasses, microphyllous shrubs and succulents, desert annuals)

Example of secondary plant succession

- First thing to grow on a left over far space are weeds, these are eventually overshadowed by pioneer species which are overshadowed by.....this sequence is essentially a progression from r strategists to K strategist

Heuristic models versus management tools -> read about it

- Fluctuations and oscillations in these models are entirely from density-dependent processes natural to the population - The equations capture the "something" that causes density dependence through the abstraction of the "carrying capacity" - Do not identify possible limiting factors like food supply, space to live, susceptibility to disease, bad/good weather, seasonality (temperature/osmotic stress, food supplies) - carrying capacity for animals in temperate biomes set by winter conditions - for practical applications, the above models would never be useful - would need a species-specific model - have covered the major points of simple, single population, deterministic growth models - will introduce stochasticity, age structure, multiple species - most important differences among individuals are age and sex - probabilities of giving birth and dying are not the same for all classes - In age structure models of population growth: divide the population into age classes; each age class will have age-specific prospects of death and reproduction - Keep track of females only - can just do the math on females and multiplying by 2 - build models in which females produce daughters

Ex of a forest grown on once-farmland

- Forest floor has smoothness of a once-plowed surface - closed canopy with trees 20-25m high - recent agricultural heritage obvious - a large swath of land entered secondary succession all at once

Structure of TDFB

- Forest interiors are dark - Light= precious ressource - photosynthesis takes place high in leafy canopy - Trees grow so tall because they need to compete for light and shade out competitors - soil moisture + nutrients adequate - light is principal limiting source - very little photosynthetic tissue below upper canopy

Epiphytes

- Full-sized plants that grow wéroots attached to the trunksébranches of other plants ( depend on getting seeds dispersed into humus-filled crotches of high branches) Epiphytes and lianas: specialized for moist and light-limited environments (cheap way for a plant to get to sunlight wéo building own trunk) depends on wet tropical conditions )

Ferrell and polar cells

- Hadley cells are continuous -When air falls to 30˚N&S it is pushed both northward and southward - flows that move toward the poles initiate a second pair of conveyor belts : Ferrell or mid-latitude cells

Plant physiological ecology as a tangle of constraints and tradeoffs

- Heat balance and water balance are critical - Evaporative cooling is the process that ties heat regulation and water regulation together - plants are autotrophs = energy from the sun through photosynthesis - terrestrial plants(not cacti) do Photosynthesis through their leaves - leaves use evaporative cooling to prevent overheating - gas exchange though stomata - Leaf can stay cool despite receiving full sun if supplied with enough water and has air flowing across leafs - Some are biochemical specializations of the pht. pathways - Our zone exhibit C3 pathway (Co2 molec incorporated into 3carb molec) = not efficient water use= wasteful photorespiration at high temperatures

Extreme synchronization may have additional consequences that could act as selective forces in maintaining it

- If a plant population produces a constant crop of seed every season, populations of seed predators build up levels sufficient enough to kill nearly all seeds produced - if seed production synchronized so that years of high seed are interspersed among more common years of no production, populations of seed production, populations of seed predators are kept under control * during years of high seed production, even tho populations of predator's increase, they become satisfied before wiping out all of the seeds

Sclerophylls

- In cold northern regions: conifers have tough resistance sclerophyll leaves + flexible branches in order to shed the snow - In warm regions south: smaller leaves = less vulnerable to the sun

As Gleason claimed

- Individualistic responses along environmental gradients - React more to abiotic conditions than to biotic - variation of the composition is continuous - When we see apparent ecotonal zones of abrupt vegetation change there is usually an abrupt change in abiotic soil factors, if not it is due to large dominant species - Clementsian sort of biotic interactions between plant species that do influence their joint distributions are typically small in comparison to abiotic forces. Animal communities are more Clementsian.

Many mobile animal characteristics undergo a temporary life-history state of migration

- Juvenile animals near the age of reproduction are driven out of their habitat to find territories of their own - have high v_x values during this time - These effects weakened in species where males are more likely to be the ones that disperse - This principle important in captive breeding programs are used to help the conservation of endangered species In plant/animals some species reproduce once in their lifetime and then die (semelparity) others can reproduce numerous times (iteroparity )

Continental climates

- Lack water dependent buffering of temperature - Hotter summers, frigid winters - The great lakes exert some maritime-climate effects

Deciduous habitat is drastic

- Latitudinal belt that contains temperate deciduous forest: 35-50 degrees north

Broadly applicable life history strategies: the r-K dichotomy

- Life-history characteristics do not vary independently across species - certain traits tend to co-vary= clusters of traits with fast or slow life histories

Why are these leaves appropriate adaptations for the boreal forest:

- Long winters with short growing seasons - advantage to evergreen - Can start photosynthesizing right when temperature gets warm enough, doesn't have to wait to grow leaves -can't lose leaves to late/early snowfall - better able to shed snow

Inverse density dependence: Allee effects

- Mays equation and the classic logistic both produce maximum growth rates when the population is at its -lowest numbers - any increase in numbers above zero exerts a crowding effect that slows population growth - the most obvious downside of low density lies in finding mates *If N=1 logistic would tell you that per-capita growth rate should be at a maximum, not true irl - Animals are mobile and good at locating mates so low density isn't detrimental to them - plants with sparse populations particularly suffer

Chemical defences

- Metabolic poisson - Deterrents

Boreal forest dominated by coniferous spruce and fir trees also have woody angiosperms: shrubby willows

- Milder climates - large shrubs 2-3m high - can't grow well in dark forest understory - depend on dams from beavers flooding + killing conifer trees, opening up habitats to full sunlight - thrive in hydric soils - beaver take this to their advantage = creation of many dams

when some organisms produce lots of offspring

- Most die off - Some survive Results in a curve that initially drops steeply & then levels off

Extension to more than 2 species

- Multi-way competition b/w multiple species - write differential equation for each species, substract more braking terms The set of all å values arranged as a square matrix = community matrix; can predict population trajectories of a whole set of interacting species

Natural selection and traits

- NS does not act directly on traits or genes in isolation - adaptive evolution of a particular trait depends on the overall effect on fitness and the organisms ability to succeed or fail

Cost of reproduction

- Offspring require energy and nutrients that adult could use for other purposes - parental care ex: lactation - Parent survival can be reduced * b_x schedule affects I_x schedule - parental ressources for reproduction can be depleted = subsequent offspring production is delayed + diminished * high b_x early in life reduces b_x late in life

Early vs late reproduction

- Organisms that reproduce earlier do not have as long of a period to accumulate resources, can't make as many offsprings as those who wait. - Expect natural selection to produce a waiting period that is optimal in the current environment

less severe deserts

- Persistent drought is relieved during one or two brief wet seasons

Why do certain sets of plants co-occur or not

- Recognizable and repeatable plant associations occurred bc constituent species functionally dependent on each other's presence - Causes had to be rooted in biological characteristics of species - a plant community- superorganisms: its parts were functionally integrated + passed through developmental stages - phytosociology plays a particular role - particular plant communities could be seen as belonging to discrete community types (lead to higher taxonomies of vegetation types - true vegetation types would be separated by a special type of narrow transition zone called an ecotone

Example of soil development in primary succession

- Sand dunes = poor conditions for plant growth - marram grass does well in these conditions, forms extensive root system that stabilizes the sand and grows fast -This allows other, slower-growing species to establish - gradually out compete marram grass ex: of tradeoff b/w growth rate & competitive ability - these species contribute organic matter to the soil - gradually the sand becomes a complex soil = marram, paved the way for its own replacement = Facilitative force

Gap-phase succession

- Spatial scale - Ecologist got accustomed to thinking of succession as a stand-level process. -

Succession: a stochastic process driven by fixed probabilities of species replacements

- Species diversity is low in pioneering stages - in absence of disturbance diversity rises and then falls - Succession proceeds to a low diversity climax - to maintain highest level of diversity requires an intermediate intensity of disturbance

K: strategists

- Species with opposite attributes from fugitive and annual weeds (slow growing, good competitors) - Have adaptations for high-density, competitive situations

Animals of the tropical rain forest

- Squirrels, porcupines, deer - Plants majorly adapted to pollination and fruit dispersal by animals - Especialized fruit eaters (frugivores): birds, parrots, toucans, bats, monkeys - year-round superabundance of foliage (sloths, leaf-eating primates) - Warm climate favors ectotherms (reptiles, amphibians, insects, lizards, frogs, birds, ants)

Classical climax idea fails in Boreal forest biome

- Succession from various starting points lead to close-canopy forests of spruces and fir - Dark forest- no understory young saplings to replace current generation -endpoint of succession (not stable, self perpetuating climax like expected) - Canopy trees keep getting older and taller until they are susceptible to wind storms, fungal attack and herbivorous insect, fire = secondary succession sequence w/ shade intolerant pioneers in an open environment

A couple of biomes we are basically ignoring

- Temperate rainforest - Tropical thorn scrub

Gap phase succession is very common

- The forest is not uniformly old-growth; is a complex spatial mosaic of many patches of different ages

More flexible forms of density dependence

- There are alternative models that capture a more realistic range of dynamics - difference-equation model (popularized by Robert May) - Starts with geometric growth, adds a carrying capacity to which the population returns by density dependence - key innovation: allows time delays in response - Population size N is compared to K at a particular time interval - if population size below carrying capacity, there will be compensating surge of growth - but added individuals don't show up until onetime intervals later - no guarantee that this increment of growth brings -the population exactly to K (may be less or exceed K) N_t_1 = N_te^(r(1-Nt/k)) -bracelins term -> difference equation models allow time delays in response - e,r and K are constants (r(1-Nt/k)) -e takes the place of ¥ as the factor by which population size changes over the time interval being examined - not a constant - varies, depends on: relationship b/w current population size and carrying capacity - (1-N_t/k) is the braking term: how far the current population size is from carrying capacity * its sign indicates whether current population size is above/below carrying capacity - r: a measure of a populations ability to grow, or measuring the strength of density dependence *big values r= population will rebound more strongly toward carrying capacity = overshoot and complicated dynamics, followed by undershoots

Ocean temperatures and precipitation

- There will be more potential rain on land if the winds blowing from the ocean have been blowing over warm water - If water is warm, more water evaporates and warmer air can retain more water vapor

Habitat specialist

- These animals are probably cognitively limited: this neuron circuitry has adaptive value in past environments but is maladaptive in today's transformed landscape Ex: Kirtland's Warbler: a small insect-eating bird that is going extinct bc it only nests in forests of jack pine that have grown after fires that occurred 5-20 years before.

Structural defences

- Thorns, - Spiky hairs - abrasive silica -physical toughness

As environment gets drier TDFB= temperate savanna

- Tree canopy becomes shorter, casts less shade - More openings/gaps where sun penetrates - Vegetation= scattered trees, sun-drenched grassy meadows

Tropical deciduous forest biome

- Tropical areas that experience wet and dry seasons - Deciduous- less costly to drop leaves during dry season than to keep them - Many species produce flowers during dry season

2. Dwindling populations of endangered species

- Typically vertebrates - motive: legal responsibilities to devise management plants to stave off extinction - Exact numbers do matter

Evergreen leaves that last years are less costly

- Use fewer resources of (N,P,K) - When pine needles fall off, slowly decay, acidity contributes to leaching loss of N

For TDFB to develop

- Warm summers and cold winters - Precipitation has to be ample all year-round -Flowing streams - Areas stay wet enough that forest fires are rare - Annual leaf fall= regular infusions of organic material to soil

Equilibrial view of community structure

- Whether or not 1+ species can coexist depends on patterns of resource use - populations grow until they can reach the carrying capacity of their environments - potential members of the community will be sorted through competition until only the ones with different niches remain

Prevailing winds

- Wind characteristics (direction, force, reliability) are different in different places on earth - Wind patterns are critical influences on organisms and ecosystems 1. Redistribute heat and water vapor, from oceans to continents 2. W/o this, continents would be deserts - winds are named from the direction they come from (Nwinds blows from N-> south) - the 6 cell circulation pattern imparts northerly and southerly components to prevailing wind directions: 1. b/w 0 N and 30 N: Hadley cells push air N->S 2. b/w 30N to 60N: Ferrell cells puss air S->N 3. b/w 60N to north pole: Polar cells push air south (opposite fro southern hemispheres)

What about populations in the wild

- all species show variability in numbers through time - most stable populations: long-lived, large-bodied animals with low reproductive rates ex: 1. tropical territorial birds: a juvenile can't breed until a territory holder dies= constant numbers 2. Insects have a population outbreaks/interruptions * have very short generation times = very high potential r value if weather is favorable and food supply is high -> ex: occasional outbreaks of locusts in Africa= such high #'s that they wipe out all vegetation * Similar effects in North America with forest/agricultural pests - These dynamics not well described by the logistic equation ; -we are not seeing gradual, inevitable ap[proaches to equilibrium - but density is at work: violent population outbreaks of insects are usually followed by violent population crashes, which tempers population growth - In density-dependent versus density-independent effect on population, d-I would be the factor causing population outbreak, and d-d would be the factor causing a population crash (ex: disease) - There are mathematical models for the spread of disease - density dependence of transmission is the key factor - variation transmission probabilities carries important implications for why some diseases are mostly benign, while others are devastatingly virulent

Leaching depends on

- amount of leaching depends on the age of the soul (Australia:old, Ontario: young). Important sources of fresh parent material - also depends on water-retaining capacities. Can be well drained

As time goes by: 1 classical approach

- analytical, deterministic models - uses calculus; differential equations - makes predictions about population changes through time - dN/dT = some function * solving produces an exact prediction of the populations growth trajectory - Deterministic= outcome of such models is completely determined by starting conditions and fixed parameters - For any set of conditions there is only one result - Start 2 models of density-independent growth and then adding density dependence to produce the logistic equation - later will consider 2-species of the models to treat interspecific competition and predator-prey interactions - The critical limitation: these models have to be analytical soluble * Usually too simple to be accurate descriptions of how real populations behave in real life conditions * only capture the essential process

Starting with plants

- annuals are quite common - especially in high seasonal deserts with long annual dry periods that expose plants to extreme water stress - to be perennial in these conditions: be a cactus or stay dormant as a seed during the entire dry season Weeds are also common annuals - grow in transient habitats that have been disturbed

I_x values

- are probabilities - they range from 0-1 - newborns are alive at birth so I_0 = 1 - get smaller as x increase (probability of being alive declines with age) - Last Ix value is zero - Shape of survivorship schedule is an important component of an organism's life history (graph of I_x vs x) - Every species has its own characteristic shape - All organism's breakdown eventually through senescence (aging)

patches

- areas that are within the range of tolerance of the species

Life tables: math and notation

- assign individuals in a population to classes based on their age - x = age - time-span for an age class interval is chosen for convenience *for humans, typically 5 years' long; 20 age classes = human lifespan - first age class denoted by subscript 09 - total population of N divided into n_0 newborn - Total population size: ∑nx=N - capital sigma indicates you sum up the following variables over all possible age classes - n_x values= age structure of the population *represented as a horizontal bar graph called an age pyramid - now have different birth+ death rates for each class - age-specific risks of mortality = survivorship schedule * I_x = survivorship at age x = probability that an individual is still alive at age x

Emergent properties

- attributes of a whole system that are not inherent in the individual parts of the system

Fecundity schedules

- b_x (m_x)= avg number of daughter's produced by a female in her xth year of life * not probabilities so can't exceed 1.0 - typically b_00 - schedule fecundity will differ for different organisms Key elements: total # of offspring produced + waiting period before reproduction can begin (age of first reproduction) - lacks density dependence just like the survivorship schedule - considers how fecundity and survivorship interact * consider average reproduction of women - the # of daughters she can produce in her lifetime: ∑ b_x = sum of all age-specific fecundity values - Multiply each b_x value by the corresponding I_x value; then sum up those products across all age classes x = net reproductive rate/ net replacement rate = R_0 R_0 = ∑l_xb_x - R_0 acts similarly to ¥ *both are multiplicative factors by which population grows from one point in time to the next R_0 = 1.0: each female exactly replaces herself = constant population size R_0 > 1: population increases geometrically w/o limit R_0 < 1: population slides toward extinction * ¥ = amount of growth that occurs over one unit of time * R_0= amount of growth that occurs over one generation (takes a generation for a female to replace herself) can get rid of "approximately" define generation time as age of a mother at the time she produces her average daughter - need to compute a weighted average - The formula generation time T reduces to T= ∑xl_xb_x/∑l_xb_x= ∑xl_xb_x/R_0 - can model future growth of the population under the assumption that fecundity and survivorship values are fixed - additional required assumption: all deaths and birth that occur during a time interval take place at the last possible instant before the next time interval begins

Factors key to these graphic patters TDFB

- cold snowy winters, long mild summers - large surface area of leaves= excellent at capturing photons for photosynthesizing - water is available to prevent overheating of the leaves by supplying evaporative cooling

Thermoconformers

- cold-Tend to be blooded animals - body temperature track ambient temperatures

Outcome 4. K1>K2/å21 and K1/å12<K2

- competition unstable - winner depends on starting numbers - species with initial advantage outcompetes the other

As time goes by: 2. More recent style

- computer intensive simulation models - run a program to compute growth trajectory - can conclude more complicated and realistic rules of growth - Easy to male models stochastic rather than deterministic *The inclusion of chance variation in the parameters of the models - Deterministic models - Stochastic model

Beyond population: moving to a more perspective on community properties-

- considering properties of a metapopulation

Boreal forest dominated by coniferous spruce and fir trees also have aspen

- deciduous angiosperm - thrive at lower elevations and latitudes - pollinated and seeds disperse by wind - shows clonal/vegetative reproduction: one tree can produce others at the end of lateral roots (whole hillsides of 100's aspen can constitute a single genetic individual from a single seed)

Animal community ecologists

- descriptive studies - extended theoretical population ecology from single-species models (logistic)to multiple-species models - mathematical field - emphasis on N-> field always data-poor - hard to track animal population sizes in irl - theories based on controlled lab experiments (microcosm studies) -> didn't capture important forces that determine community composition irl

The nature of succession is not

- determined by developmental biology as it is by individualistic responses of a species pool to a disturbance regime described by by certain types, frequency and sizes of disturbance. - Those disturbances not only provide ecological opportunities for colonizing species, but also exert a natural selection that builds adaptations for surviving or recovery from the disturbance

Ex: anolis lizard in the caribbean

- dived up habitats in patterns that reflect functional feeding niches (ground, tree trunks, crown branches)

When ranges shift

- due to a warming climate with milder winters - Climatically induces range shifts on a resident species are usually slow - When a new species is introduced to a new habitat, a dramatic range shift can occur rapidly (invasive species= spread rapidly, become pests, harmful effect on native species

Old-growth tropical forest

- example of unchanging climax - every so often a tree falls down, pulling down others with it - Resulting gap is a sunlight patch - Seedlings & sucker shoots spring up - Trees on the margin of the gap laterally extend their branches into the gap - In small patches, this inward growth of branches closes off the patch before seedling have the chance to grow in - Big patches have more complicated dynamics, seeds can grow.

3rd major pathway: CAm (crassulacean acid metabolism)

- extreme conservation - Acts mostly on succulents (cacti, epiphytes) - Stomata closed during sunny periods= minimal water loss - thick succulent leaves have enough thermal inertia to resist overheating - open stomata at night - Capture co2 and so it as organic acid - when photons are available the acid enter the rest of the pathway for converting light energy into sugar - Plant tissues show daily cycles pH change

Very hard to estimate population size in nature

- finding + enumerating individuals - deciding where boundaries of the population are - distinguishing individuals *plants: a genet can subdivide itself into ramets * sessile invertebrates -Population ecology highly relies on mathematical models. Can compute the consequences of reasonable assumptions about population growth - when studying population sizes by direct enumeration, usually on small islands or in artificial conditions

Obstacle of applying extension to more than 2 species equation in real communities

- getting accurate estimates of the pairwise å values It would require lare #'s of experiments manipulating population sizes of some species and measuring response of other species (impossible irl)

Desert animals

- heat-adaptive variants of species found elsewhere - Grazers= desert bighorn sheep - Small rodents, mostly nocturnal, depend on seeds, serves as prey for snakes and owls

Why are these leaves appropriate adaptations for the chaparral habitat

- hot dry summers= desert like - small leaves are less likely to overheat - doesn't require as much water for evaporative cooling - can find sclerophyllous vegetation in areas with nutrient-poor sandy soils - small leaves are less likely to over heat and therefore don't require as much water for evaporative cooling

Competitive/ predatory relationships

- lead to extinction in homogenized populations - lead to persistent coexistence in weakly coupled metapopultions

Massive reproductive episodes of long-lived semelparous perennials

- leads to adaptations regarding synchronization of flowering among individuals in population - plants evolve to use the same cues to induce flowering ex: Asian bamboos: all flower at the same time if from the same seed crop, even if transplanted to other parts of the world

Curtis and Whittaker

- looked at many ecological gradients - collected quantitive data - whittaker = direct gradient analysis (lecture added below) - Curtis= indirect gradient analysis

Truly replicable experiment

- microcosms or protozoa or larger mesocosms Hope that they might let us combine the power of replicated experiments with enough realism to produce results that adequately mimic natural systems

Natural enemies: predators and pathogens

- modelled similar to mass action models - ecological encounters increase with population size - repeated pattern of regular oscillations through time = endless pattern of lagged population cycles = when preys are abundant, predators have plenty to eat etc... These oscillations continue forever unless you add additional parameters(carrying capacity for prey population) to make the model more realistic - cycles tend to damp out: predator + prey level off asymptotically values & coexist indefinitely or become amplified = mutual extinction

the population grows/shrinks as a step function

- moms die, babies get born, everybody gets older - necessary calculations can be accomplished by matrix multiplications

Biome level variation

- more precipitation= taller vegetation, species-rich and productive places - Driest places: sparsely vegetated deserts - more water: short-grass grasslands> all grass parties> forests - warmer places support bigger and more complex vegetation **seasonality of temperature and precipitation is very important

Latitudinal patterns: how the sun heats the earth

- most important source of ecological variation for life on earth arises from the latitudinal gradient in temperature= hot near the equator, gradient toward cold at poles (uneven distribution of radiant electromagnetic energy from the sun - Spherical shape of the earth means sun's rays strike at different angles at different latitudes - Density of photons highest at equatorial regions (declines towards the poles)

Westerlies , easterlies, and the Coriolis effect

- no actual force at work - air being pushed northward by Ferrell cell is passing over surface of a spinning sphere - Produces a twist of the wind vectors (Coriolis effect:pseudoforce) Wind direction acquires a westerly component caused by CE, in addition to southerly by Ferrel circulation

properties addressed by community-level studies

- number of species present (species richness) -abundance of these species - usually communities compromise a few species that are very common (dominants) and more that are rare - distribution of abundance and rarity = species diversity the species assemblage

Why are these leaves appropriate adaptations for the cool northern bog lakes

- nutrient limitation - develop acidic water - lots of dead vegetation preserved as decay - hard for plants to take up nitrogen - sclerophylly favoured indirectly like in acid soils= advantageous in nutrient conservation

Acid bogs preserve more than plant material

- pollen grains are preserved more than plant material- northern European from the ice age: their bodies preserved in these bogs- anaerobic conditions

Prevailing easterlies/trade winds

- prevailing winds strongest at latitudes in the middles of atmospheric cells (15˚ to 45˚) * air being pushed horizontally across earth's surface = consistent winds - Little horizontal wind: latitudes where air packets going up 0˚ to 60˚ and coming down at 30˚ * dangerous areas for sailors: could not move for weeks *Windless equatorial are: doldrums * horse latitudes: areas at 30˚N&S - too much wind at 45˚S *Roaring forties: extremely strong prevailing westerlies * Winds so powerful there are no significant land masses here - The North $)'s have continents to interrupt and dissipate flow

Existence that is global but not local

- protozoa populations in test tubes * 1 isolated & closed test tubes = predator prey complex = extinction of prey and then predator *multiple open test tubes w/ water dripping from above= recolonization of prey in test tubes where populations went extinct by splashing = the 2 species coexist in a metapopulation of many test tubes

Using a spreadsheet to examine behaviour of this model

- r < 1= smooth approaches to carrying capacity - r> 1= damped oscillations around carrying capacity that eventually come to rest with N=k - r>> 1 = stable limit cycles (oscillations not damped like a frictionless pendulum) - r~ 4: mathematical chaos/extended chaotic trajectories * quickly sends a population to extinction - weak density depenence= smooth, logistic-like behavior - stronger density dependence,= increasingly violent overshoots

Incorporating more realism

- real patches differ in size, sustainability, occupy real positions in space, some more isolated from colonists than others, these factors can all be built into models critical process: the rescue effect - deals with differences in patch suitability expressed as the source-sink dichotomy - if a sink patch is surrounded by a healthy metapopulation w/ source populations nearby, remains occupied indefinitely - a metapopulation can capture realistic aspects of natural systems

Emergent properties of metapopulation

- shows subdivide systems can display properties that homogenous systems can not - spatial structure can stabilize interspecific competitive relationships that would be unstable in a homogenous habitat - suppose 2 species of aquatic protozoa interact according to L-V model * species 1 always outcompetes species 2 when in one tube = local stability *If species 1 sometimes goes extinct after taking over a tube & species 2 is better at dispersing to new tubes= extended global coexistence * poorer competitor needs to be a better disperser - difference in life histories allows prolonged coexistence at the metapopulation level

Outcome 1. from the equation if K1> K2/å21 and K1/å12>K2

- species 1 will always outcompete species 2 -N1->K1, N2 ->0 - species reaches its equilibrium at carrying capacity - species 2 goes extinct

Outcome 2. if K1< K2/å21 and K1/å12<K2

- species 2 will always outcompete species 1

Plant community dynamics: ecological succession

- species composition and overall plant structure of communities changes over time = succession - Succession happens quickly enough to be studied by direct observation - Forests take a long time to turn over - In order to study the change in large spans of time its necessary to do "space-for-time" distribution ex: wave action = erosion =sand from west shore to south-end of the lake = new shorelines These provided a time sequence(chronosequence)

Plant ecologists

- start from descriptive data - plant communities are big things with slow dynamics - field was data rich, dominated from 1900-1960 - easy to collect data - many theories made but were hard to test (hard to do long controlled experiments on forests)

stopped by crowding

- starvation - lack of shelter - disease

Shrublands: chaparral vegetation and the Mediterranean climate

- strong affinities with seasonal deserts but is wetter and more productive - key climatic factor: hot, rainless summer & warm, rainy winters w/ negligible frost - Vegetation: bush or scrubland small trees - plenty of fuel to sustain large fires during hot summers - mediterranean basin, California, some parts of Africa and Australia - when the plants burn- roots survive -Consequences of burning are small - good for wine grapes - in the US fires are extinguished immediately- consequence: fuel accumulates to the point where larger uncontrollable fires are inevitable after years of suppression

Animals of the boreal forest

- summer-active insect herbivores - a diverse population of migratory insectivorous birds ( especially wood-warblers) - Some frugivores (less than deciduous) - lots of granivorous birds (pine grosbeaks, crossbills) ( seeds available all year= birds need special beaks- don't migrate south for winter but move around in the boreal forest) Large mammals ( deer, elk, moose & their predators = wolves, mountain lions, lynxes) All above do better in open areas- benefits from: fires, windstorm, beaver activity _ red squirrel: does fine in mature conifer forest( feed on conifer seeds, porcupine survives the winter on a diet heavy in tree bark ( can pack caecum full and let microbial fermentation slowly extract nutrients) * prayed on by arboreal weasels

Outcome 3. if K1<K2/å21 and K1/å12>K2

- the 2 species will stably coexist - both remaining below their K values at steady state The condition for stable coexistence is that each species inhibits its own population growth more than it inhibits the growth of the other species population - intraspecific competition must be stronger than interspecific

consequences of continental-maritime contrast

- the ITCZ is distorted by the great annual temperature swings in asia

The important part

- the debate of the fundamental nature of terrestrial plant communities - Need agreement on operational criterion - Need to enlarge scale of investigation to consider many objectively chosen sites

N_t = N_0¥^t

- time is now a exponent - population growth rate gets faster and faster each year - unlimited/ exponential growth/ density-independent growth (no crowding effects) - if ¥ <1, population growth rate decreases each year until extinction

The tundra biome

- treeless - higher latitudes+ elevations - artic tundra/alpine tundra - aoils nutrient poor= cold temperatures limit microbial action - low productivity - sphagnum peat moss, grasses, sedges

Geometric growth model

- variables: population size: N and time (t) - time advances in discrete steps (not continuously - appropriate for organisms which reproduce during brief annual periods (most animals in temperate animals)

V_x is important in population genetics

- variation in v_x among individuals predicts their genetic contributions to future generations - selection can favour age-dependent behaviours (mate selection, effectiveness of colonists) -in species that form pair bonds b/w mates, males prefer females with high reproductive values = tendency for traits associated w/ onset of reproductive age to become associated with sexual attractiveness

Tropical thorn scrub

- very extensive dry places: Africa, Mexico, South America - variant of chaparral - tropical savannaégrassland and hot deserts - plant and animals with exquisite adaptations - not appealing in appearance

Flowering plants of the tundra

- very small -cushion plants - any branches sticking out are pruned by the wind - stems and leaves miniaturized, flowers often full sized and very showy (bees, and flies for pollination)

Synthesis and conclusion

- world heterogenous place - spatial structure - interactions have time lags - frequency + magnitude of disturbances is equally important - patchiness is everywhere - spatial and temporal scales of patchiness is important, affects interactions (see gopher + lily example fo lecture) - metapopulation structure with infrequent migration changes outcomes of interactions - occasional disturbances that know back succession can also encourage coexistence + species diversity - Spatial patchiness & chance events are critical to ecologica; outcomes - determine species characteristics through evolution - Species are adapted to the spatio-temporal graininess of their landscape, not just to average or typical conditions - we cant understand an organism w/o understanding the environment it lives in

Size: Bergmann's rule

-Cold environments organisms tend to have larger body sizes, - lower SA/V ratios (retain heat better and loose less to cold surroundings) - Lots of exceptions to this rule tho Ex: bird wings: increase S/A but are needed to keep warm

Animals of grasslands

-Grazing mammals - All plant biomass close to the ground - African savanna: herds of antelope, zebra and others (migrate following rains brought by intertropical convergence) - N.A bison, pronghorns - massive extinctions due to hunting in NA. --> hunting hypothesis humans feel psychologically comfortable only in savanna habitats

Hedley cells

-IR radiation from the surface heats up near-surface air, decreasing its density = 1. Meteorological low-pressure zone 2. Impels the heated air to rise above the solar equator - as air rises, creates a partial vacuum beneath it - When air reaches upper atmosphere, is cold and heavy, descends at 30˚N and 30˚S latitude - sinking air warms up - After sinking, packets of air pulled up to solar equator, converge and rise again - These movements establish 2 continuous circular loops each about 30˚ wide Summary: - air amasses at the earth's surface tend to move towards the equator while air masses at higher altitude are moving in the opposite direction. -Set prevailing winds in motion + affect precipitation profoundly - Air in upper atmosphere is very dry - Air coming down in Hadley cells at at30˚N&S is hot, dry and desiccating (high-pressure weather systems) (sparsely vegetated desserts) - Wettest and dryest places on earth have their weather have their weather delivered by Hadley cell circulation

Poor soils

-In lowland tropical soils:Lateric= ancient, read, clay rich, Fe & Al - In cold northern regions: Podsolized= tan, Sandy, acidic, no N

Micrometeorology at the leaf surface: laminar versus turbulent flow

-Leaf continually swept by wind= refresh supply of Co2 and the waste O2 is dissipated. - If air is not moving 1. Stagnant air build up next to the leaf 2. Dead air gets depleted of desirable CO2 and enriched in undesirable oxygen 3. likey to heat bc convective cooling is reduced - stagnant air build up if the leaf is smooth=laminar flow Laminae: layers of air that move at different speeds - Air very close to the leaf surface is a boundary that is virtually stagnant * friction= air becomes stagnant, gas exchange only occurs by regular molecular diffusion Turbulent flow: when the leafs structure has irregularities - turbulence is desirable on a leaf Ex :oaks: have sinuses, deepen and leaves get smaller as you move to the tree= more sunlight - sinuses ate involved with thermal regulation of the leaves via induction of turbulent flow - prominent veins

The grasslands biome

-Produced when conditions get too dry & fire-prone for trees - occurs in North America, where the ratio of precipitation - potential evapotranspiration (PE) (If ratio=1; standing veget7ation gets dry enough to burn by summer lightning) - Plants resprout quickly from underground buds - Water doesn't percolate all the way through soils down deep into water tables. (nutrients are not leached out of soils, stay available in rooting zone of plants - plants tend to produce extensive and deep root systems, which contribute to organic matter -soils extraordinarily rich: deep, black, beautiful - productivity depends on rainfall - N.America gradient: tallgrass prairie in the east -> mild-grass prairie erst -> rainshadow of Rockies - Dominant species: grasses(big bluestem), forbs (herbaceous angiosperms) - Legumes(help restore nitrogen to soils, they have nitrogen-fixing bacteria in their roots- convert atmospheric nitrogengas into ammonia ) -conversion to agriculture almost complete

Traits can confer

-adaptive significance - adaptive significance

compare the shapes of v_x curves of different species or populations

-convert raw values to relative reproductive values * divide all v_x by v_0 = relative reproductive value of all newborns is scaled to equal 1.0

Animals of the deciduous forest are determined by:

1. Availability of plant material as food 2. Physical structure provided by plants

Other climate peculiarities: jet streams

1. Jet streams: Wind currents high in the atmosphere 2. Our weather influenced by northern polar jet stream - Can form at boundary between Ferrel and polar cells - They blur/transgress usual boundaries b/w cells = unusual storm system or heat spell in higher latitudes

When attempting population sizes in nature, 2 categories

1. Pest species 2. Dwindling populations of endangered species

Extreme chaparral soils pose 2 stresses:

1. Sandy soils have little water retaining capacity - plants can experience desert- like droughty conditions during summer heat waves b/w rains 2. Lack of soil nutrients, especially nitrogen - keeping leaf for several years is much cheaper than dropping it and replacing every year

Sclerophylly prevails in at least four habitats

1. Semi submerged plants in acid bogs and ponds in various temperate (mild temperatures) habitats 2. Cold boreal forest biome; snowy reasonable amounts of rain 3. Very dry, well drained, sandy soils in warm habitats 4. Mediterranean/chaparral biome; wet winters (no snow) very dry hot summers

Abiotic factors:

1. conditions: physicals states that cannot be depleted (temperature, ph) 2. Resources: necessary physical entities that organisms use up - Limiting factors: factors important in determining whether species can or cannot persist in an area *"The Big Two": temperature(condition) and water (resource) = most likely to limit the distribution of terrestrial species **Weather+climate determine what sorts of organisms are found in different parts of the world** -Environmental gradient(gradient of soil moisture) - Trasect: represents a gradient - species "sort themselves out" along gradient= reveal their differential sensitivity to a certain resource - Any factor can be treated as a gradient treated as a gradient in this way: temperature, pH, salinity, organic content of the soil, altitude above sea level (montainous levels) ** most species in montane regions are restricted to well-defined elevational ranges

Component processes in heat transfer

1. conduction: direct transfer of heat between 2 bodies that are in contact, from warmer to cooler. Given time objects will equilibrate at the same temperature 2. Convection: heat transfer facilitated by a moving fluid - Usually water or air -equilibration is minimal - increase rates of heat transfer - water is a more effective medium - water has a high specific heat capacity, more energy must be transfer to change its energy - water sucks great out of a warm animal very efficiently - w has a high heat of evaporation: evaporation from a moist surface is a very effective way of cooling Combination of convection and evaporation cooling is potent

2 situations where predator-prey cycles are most pronounced

1. low species diversity where predators have little choice 2. Where predators are obligated specialists that can successfully consume only 1 type of prey

2 consequences for TDFB

1. most of the consumption of living leaf material is by insects 2. most of the plant biomass enters the food web through decomposition on the forest floor ( microbes , earthworms and beetles)

2 large issues regarding classification of k/r selected species

1. most of the variability in nature is continuous - hard to categorize; intermediate states exist between poles of dichotomies 2.more categories are artificial and arbritary, even if they reflect nature well - A categorie usefulness depends on its ability to bring together a substantial set of similar entities

soil disturbance

= Brief period for small annual plants to occupy a bare site before being pushed out by taller plants

autogenic processes

= Facilitative = One prevalent species changes the environment in ways that facilitate that species replacement by another - Environment is changed by the species themselves

net reproductive rate (Ro)

=Σlxmx lx=probability of given alive at x age mx=# daughters born

generation time (T)

=Σxlxmx x=female's age

Which of the following represent factors that can keep transposable element copy number under control in the genome? i. Silencing through DNA methylation and small RNAs ii. Natural selection acting on individuals iii. Tumour suppressors iv. Meiosis prevents increase in copy number A. i, iii B. i, ii C. i, iv D. iii, iv

A or B.

Wandering albatrosses are exceptionally good at taking advantage of prevailing winds to fly long distances while using little energy. Professor Frederickson discussed in lecture that they are adapted to the "roaring 40s", and that they generally fly in the direction of prevailing winds on their foraging trips, which can span many degrees in both latitude and longitude. An albatross observed flying at 25 degrees south is most likely flying in which direction? A. North B. East C. South D. West

A or D.

Which of the following insights formed the basis of the modern evolutionary synthesis? A. Continuous phenotypic traits can be explained by the inheritance of many discrete genes. B. Genetic recombination is responsible for most heritable variation. C. Most molecular variation is due to mutant alleles that are selectively neutral. D. Natural selection requires heritable variation and differential reproductive success.

A or D.

What is a quantitative trait?

A quantitative trait shows continued variation. This is because the trait is the sum of several small effects caused by the gene. An example of this is an animal's metabolism, which is under the influence of many different genes. The final products of the metabolism, as for instance milk yield or growth rate, are good examples of quantitative traits. If several small gene effects are present, the phenotype values for a population will typically have a normal distribution.

Function

A role a given trait or feature was selected to serve. -a feature increases an organism's ability to survive and pass on its genes.( adaptive character)

A researcher samples different populations of a species of plant and finds that plants grown in northern locations have blue flowers and plants grown in southern locations have yellow flowers. She decides to grow seeds from northern populations in southern locations (i.e., northern transplants), and seeds from southern populations in northern locations (i.e., southern transplants). Which of the following statements is CORRECT? A. If flower colour is a phenotypically plastic trait, the northern transplants should have yellow flowers. B. If flower colour is the result of adaptation to local conditions, the southern transplants should have blue flowers. C. If flower colour is a phenotypically plastic trait, the southern transplants should have yellow flowers. D. If flower colour is the result of adaptation to local conditions, the northern transplants should have yellow flowers.

A.

According to the excerpt from Lab Girl, what is the significance of finding wooden fossils in ancient arctic forests? A. They show that trees can survive several months of near-constant light or dark B. They can be used to grow up the ancient relatives of living plant species C. They indicate that temperatures in the arctic are too low for plant life to grow D. Their tissues can be used to determine where these species first evolved

A.

Based on the material you covered in Lab 1, which of the following statements is CORRECT? A. Insects that exhibit complete metamorphosis have adults and juveniles of very differing appearance. B. Beetles exhibit incomplete metamorphosis. C. Insects that exhibit complete metamorphosis are less abundant than insects that exhibit incomplete metamorphosis. D. Adults and juveniles of insects that exhibit incomplete metamorphosis use different resources.

A.

Given the information in the life table below, what is the generation time (T) of this population? (x=age class, lx=survivorship, bx=fecundity) x lx bx 0 1.0 0 1 0.5 2 2 0.25 4 3 0 0 A. 1.5 B. 2 C. 3 D. 4

A.

Given the information in the table below, what is the survivorship (lx) of this population for age class 2? (x=age class, nx=number of individuals at the beginning of the age class) x nx 0 100 1 75 2 50 3 20 4 0 A. 0.5 B. 0.67 C. 25 D. 50

A.

In Chapter 1, how does Jerry Coyne describe the process of speciation? A. The evolution of reproductive barriers to interbreeding between groups B. A process that usually takes million of years to occur C. Morphological differences between unrelated individuals D. The evolution of novel morphological adaptations

A.

In Chapter 4 of Why Evolution is True, why does Coyne describe life on oceanic islands as "unbalanced" in comparison with other areas of the world? A. Only those continental species that are capable of long-distance dispersal can arrive on oceanic islands. B. Island ecosystems are fragile and susceptible to biological invasions. C. Oceanic islands are unsuitable environments for land mammals, reptiles and amphibians. D. Natural selection is generally weaker on islands because of genetic drift.

A.

In Robert Paine's 1966 experiment, mussels became the dominant species because of the removal of: A. Their predator B. Their parasites C. Their microbiome D. The tidal environment

A.

In a rainforest, how would you expect precipitation to compare to potential evapotranspiration (PET)?A. PET is almost always less than precipitation B. PET is always the same as precipitation C. PET is sometimes less and sometimes more than precipitation D. PET is almost always more than precipitation

A.

In lecture, we discussed a conceptual example in which two species that cannot coexist in a single island population may be able to coexist in a metapopulation of many islands. Which of the following must be TRUE for this difference to exist? A. Occasional migration between islands must occur B. Carrying capacities must vary through time C. Some islands must be larger than others D. Both species must be predators

A.

Lecture 15 developed an argument that the evolution of the weasel body is governed by a particular tradeoff. In that argument, what two factors or processes are trading off with each other? A. Thermoregulation versus hunting proficiency B. Thermoregulation in hot environments versus thermoregulation in cold environments C. Body mass versus surface area D. Surface area versus body fat

A.

Male cardinals have bright red plumage whereas female cardinals have plumage that is a duller reddish-brown. You hypothesize that this sexually dimorphic trait arose due to sexual selection. Which of the following results would best support this hypothesis? A. You compare males that are a duller red with males that are a brighter red and observe that males with brighter red plumage mate with more females than males that have duller red plumage. B. You observe male and female cardinals and observe that males and females have different food preferences: males eat a type of berry high in carotenoids that promote bright plumage, while females feed on nuts and seeds that lack carotenoids. C. You compare males that are a duller red colour with males that are a brighter red and observe that males with brighter red plumage are better able to escape predation. D. You measure the lifespan of males that are a duller red colour with males that are a brighter red and find that males with brighter coloured plumage live longer than duller coloured males.

A.

Over the past 30 years, killer whales have been preying upon sea otters as their usual prey has declined due to global warming. What effect has this had on undersea communities in the North Pacific? A. Loss of kelp forests B. Expansion of kelp forests C. Greater predation of sea urchins D. Less predation of otters

A.

The extraordinary species diversity of tropical rainforests is paradoxical, because the principle of competitive exclusion predicts that species with similar niches will not coexist. Which of the following provides a resolution to this paradox? A. The Janzen-Connell hypothesis B. The Green World hypothesis C. Bottom-up control D. Assisted migration

A.

The principle of superposition states that: A. In the sequence of sedimentary rock layers, rock layers found on top tend to be younger than those found farther down. B. The absolute age of a rock layer can be inferred from their relative position in a sequence. C. Where a fossil is found in a sedimentary sequence can tell you about its trophic level. D. Soft body parts are more likely to be found in higher layers.

A.

What do founder events result in? A. A severe reduction in genetic variability in populations. B. An increased likelihood of speciation. C. The promotion of invasive species. D. The evolution of clonal propagation.

A.

What is an example of a vestigial trait? A. Wings of ostrich B. Fur of dogs C. Streamlined bodies of dolphins D. Gills in fish

A.

What would be good evidence of a trophic cascade? A. Removing a tertiary consumer alters the structure of the food web. B. The presence of both omnivores and carnivores. C. The absence of decomposers. D. The food web is robust to the addition of a new consumer.

A.

Which biome has a plant community dominated by short, cold-tolerant plants and a climate characterized by long winters and short growing season? A. Arctic tundra B. Temperate grassland C. Chaparral D. Desert

A.

Which of the following BEST describes why a multiple-herbicide treatment is more likely to prevent the evolution of herbicide-resistant weeds than using a single herbicide? A. Resistance to multiple herbicides likely requires more mutations or a more complex mutation, making it less likely to evolve. B. Single herbicides are more likely to increase mutation rates than multiple herbicides. C. Multiple-herbicide treatments would favour balancing selection. D. Gene flow is prevented with multiple herbicide treatments.

A.

Which of the following did NOT influence Darwin's ideas as he formulated his theory of evolution by natural selection? A. Mendel's theory of inheritance. B. His five-year voyage on the Beagle. C. Malthus's writings about the growth of a population with limited resources. D. Lyell's principles of uniformitarianism.

A.

Which of the following explains the difference in species composition between oceanic and continental islands? A. Continental islands were once connected to the mainland while oceanic islands arose from the seafloor and only harbour life that was able to migrate there. B. The environment on oceanic islands is too homogenous to harbour mammals or other large forms of life, whereas continental islands are bigger and have more diverse habitats. C. Oceanic islands are much smaller than continental islands and thus species experience fiercer competition for resources which can lead to extinction. D. More species are able to colonise continental islands because they are located closer to continents than are oceanic islands.

A.

Which of the following explains the existence of convergent forms of animals occupying similar habitats in different areas of the world, such as the sugar glider in Australia and the flying squirrel in North America? A. Similar environmental pressures cause the evolution of similar features in taxa that are not closely related. B. The convergence is not real as the environmental pressures these species face are actually very different when they are tested experimentally. C. Convergence is a result of chance. D. Convergence is a result of shared ancestry.

A.

Which of the following is NOT an example of an advantage of asexual reproduction? A. Increased mutation rate B. Avoidance of predation and disease risk C. Maintenance of pre-existing favourable allele combinations D. Transmission of more gene copies per offspring

A.

Which of the following is an example of a trade-off? A. The elongated shape of a weasel is efficient at losing heat and permits hunting in burrows. B. Temperate animals tolerate a wider range of temperatures than tropical animals. C. The feathers of Clark's Nutcrackers puff up in cold weather and are necessary for flight. D. Volume increased faster than area with increasing body size.

A.

Which of the following statements about the evolution of post-mating reproductive isolation is FALSE? A. It often evolves due to the direct action of natural selection. B. Genetic drift can play a role. C. It is caused by combinations of genes in hybrids that lead to low fitness. D. It can be observed in laboratory crosses.

A.

Which of the following would you expect to find in a species that is socially and sexually monogamous? A. Males and females that resemble one another B. Males that are very brightly coloured C. Females that have more elaborate ornamentation than the males D. Males that physically compete with one another for matings

A.

Which statement BEST describes the differences in genetic diversity observed between teosinte and maize (cultivated corn)? A. Founder events have led to a loss of variation in maize compared with teosinte. B. Genetic variation in maize is preserved by artificial selection. C. Genetic diversity in teosinte has been lost because maize replaced its ancestor. D. No genetic differences were observed because teosinte is the ancestor of maize.

A.

Which statement about models of genetic variation is CORRECT? A. The Classical School thought that most variation was harmful and due to new mutation. B. The Neutral Theory called into question whether mutation was the ultimate source of variation. C. The Balance School predicted there should be high heterozygosity but low polymorphism. D. Allozyme variation studies have definitively rejected the Neutral Theory.

A.

Why do Olavius worms near the Tuscan island of Elba require at least two different symbionts? A. Sulphite is a limiting resource at this particular location B. They are both required in the oxidation of sulphites C. One symbiont provides amino acids for making proteins while the other symbiont provides sterols for making hormones D. In order to harness the sun's energy

A.

Why do the phylogenetic trees of aphids and Buchnera exhibit similar branching patterns? A. Aphids and Buchnera have diversified in parallel since an original infection in the ancestor of modern aphids B. Independent lineages of aphids were infected by different strains of Buchnera over the course of their evolution C. Diversification rates in aphids and Buchnera are dissimilar owing to differences in gene flow among population D. Extinction rates in aphids and Buchnera are similar because they are codependent for survival

A.

Why do you add Triton X-100 when you are preparing your leaf sample for the chemical assay? A. It breaks the chloroplast membrane and releases polyphenol oxidase (PPO) into the cytosol of the plant cell. B. It absorbs phenols so it prevents PPO from interacting with other phenols. C. It acts as a substrate to react with PPO to produce quinones. D. It keeps the pH of the solution constant.

A.

Why is eating plants a tough lifestyle? A. Plants have evolved structural and chemical defences against herbivores B. Plants are hard for herbivores to find C. Plants and herbivores have undergone parallel adaptive radiations D. Mammals often lack highly specific detoxification pathways for dealing with secondary compounds

A.

patagonia

Abiotic factors dominate and landscapes are geologically young. Abrupt treeline governed by abiotic factors

Homothermic vertebrates

Achieve insulation with subcutaneous layers of body fat or fur or feathers - Air is a great insulator if prevented from moving - Fur/feathers trap air and prevent convective flow : compromise 1000's of modular structures that can be replaced as they wear out so the insulating layer doesn't degrade Animals can grow insulation= appropriate to colder/warmer times of the year (seasonal shedding) - Mamals= contracting the arrector pilli muscles Bird- lift outer contour feathers= create a dead space - Land base part-time swimmers make use of regular dead-air insulation (penguins-otters) * keep fur waterproof through oil secretions and preening - Mammals that are continually immersed (dolphin, wales) depend on subcutaneous blubber= insulation + longterm storage of food energy

Lotka Volterra competition model

Adds a second breaking system. Which accounts for interspecific competition exerted by a second species -Need two simultaneous differential equations for species 1 and 2 (look at paper)

logistic equation

Adds braking term to exponential growth to slow down growth as more individuals use up resources * Braking term = infraspecific competition

Hunting hypothesis

African mammals evolved while humans and their hunting techniques evolved - humans-> new places> hunting techniques to "unprepared" grazers

Heterotrophs/ consumers

All other species that do not photosynthesize

deterministic

All population models looked at so far. - parameters that determine births and deaths treated as constants = outcome completely determined by starting conditions IRL chance variations will intrude and need to include realistic variability to make realistic predictions

NPP- TDFB

Amount of new biomass produced annually through plant growth - measured in energy content per unit area per time. In TDFB about 5000kcamm-2year-1 - 2/3 in form of wood - rest= production of leaves, flowers, fruits

Concluding remarks on biomes

Amounts o and seasonality of temperature and precipitation determine the biomes - Phenological timing is important - environmental challenges affect the success or failure of an individual organism

Ecological niche 1920's definition:

An animals funtional role within a community, its food relations: its prey & predators

Shape: Allen's rule

Animals from hotter environments = longer _ thinner appendages - Increase surface area - extremities specialized for dumping heat by managing blood circulation

Contercurrent circulation in extremities

Animals whose appendages are exposed to cold= arrangement of vessels called countercurrent circulation * Direct contact between arteries (warmblood) and veins (cool blood) *with vessels closely appressed, heat exchange can occur - continuous temperature gradient between the two vessels

Ecological niche 1950's definition:

Any way in which one could characterize differences among species - Envision plotting species use of resources or habitats - create an n-dimensional hyper-volume of 'niche space' in which each species would have a characteristic location - Species would be different in a way that comprehensively takes in many ecological aspects

Both desert and weedy annuals

Are adapted to take advantage of brief windows of time during which rapid growth is made possible by milder conditions - Develop long-lasting seed banks in the soil= large portion of population underground at all times - Have adaptations that selectively promote seed germination at the right time Desert annual seeds:Have water-soluble inhibitors in the seed coats Weedy annual seeds: germinate when struck by sunlight

Trophic cascades

Are more likely to be found in aquatic systems than terrestrial ones - Due to the comparative absence of spatial structure especially small ones - Aqueous habitat lacks barriers to dispersal, species are effectively stirred io in a homogenous way that lets them interact more completely. - They behave more as populations and less like metapopulations - Terrestrial systems will tend to be more heterogenous( more diverse), and therefore more unruly

Range limiting factors

Are partially hierchical -climate: organisms will grow and survive best in certain combinations of temperature -tradeoffs: hard for organisms to be equally well adapted to different environments -physiological mechanism and compensating behaviours work well only in certain places ** variation in climate draws the outermost lines that co rain a species range

The most basic aspect of living organisms

Astonishing ability to meet the challenges of a hostile environment to grow, reproduce, adapt and diversify

Given the information in the life table below, what is net reproductive rate (R0) of this population? (x=age class, lx=survivorship, bx=fecundity) x lx bx 0 1.0 0 1 0.5 2 2 0.25 4 3 0 0 A. 0.75 B. 2 C. 4 D. 6

B

A metapopulation is: A. A population that fits the predictions of theoretical models. B. A group of spatially separated populations of the same species. C. All populations of different species in a given area. D. A population made up of more than one species.

B.

A plant species exhibits continuous variation for flower colour. Crossing red and white individuals will result in offspring with which phenotype? A. Some offspring will have red flowers and other will have white flowers. B. Offspring will show a variety of floral colours ranging from red to white. C. All offspring will have prink flowers, which is an intermediate phenotype between red and white flowers. D. All offspring will have red flowers.

B.

According to the excerpt from I Contain Multitudes, which of the following statements about herbivory in mammals is TRUE? A. Herbivores have similar gut microbiomes primarily due to common ancestry B. Herbivory promoted diversification by creating new ecological opportunities C. Herbivores require gut microbes to synthesize amino acids not found in plants D. Herbivores are found in all orders except for Carnivora

B.

According to the green world hypothesis, or "HSS," which of the following trophic levels is subject to top-down control? A. Plants B. Herbivores C. Predators D. Decomposers

B.

Arrange the following biomes from lowest to highest net primary production (NPP): savanna, tropical rainforest, desert, temperate forest A. Savanna, desert, tropical rainforest, temperate forest B. Desert, savanna, temperate forest, tropical rainforest C. Tropical rainforest, savanna, desert, temperate forest D. Desert, temperate forest, savanna, tropical rainforest

B.

Base on Chapter 4 of Coyne's Why Evolution is True, which of the following is NOT a factor contributing to convergent evolution? A. Geographic isolation of different groups of species B. High rates of migration and gene flow of invasive species C. Similar environments found in different parts of the world D. Natural selection driving local adaption

B.

Based on what you read in the Lab Girl excerpt, which is NOT an adaptation of plants to prolonged droughts? A. Shedding of roots B. Production of chlorophyll C. High concentration of sucrose D. Dehydration of tissues

B.

Ecologists call all the zebras, elephants, giraffes, plants, and insects living together in a savanna a: A. population B. community C. ecosystem D. biome

B.

Even though July days are much longer in Anchorage, Alaska, than in Atlanta, Georgia, average daily temperatures are about 7oC higher in Atlanta. What is the best explanation for this pattern? A. Atlanta is closer to the Sun and so receives more solar energy B. The summer sun shines more directly over Atlanta, so it receives more solar energy per square metre. C. Atlanta is warmed by the warm waters of the Gulf Stream, whereas Anchorage's nearby currents are colder

B.

Grassland productivity depends mainly on: A. Temperature B. Precipitation C. Altitude D. Soil quality

B.

In Lab 3, why did you measure the absorbance of your sample at both the time you put it in the spectrophotometer (t=0) and 5 minutes later (t=5)? A. to make sure the measurements were precise B. Because the chemical we were measuring (polyphenol oxidase) reacts with caffeic acid as soon as it is added to the sample, its activity would increase over time C. Because the chemical we were measuring (polyphenol oxidase) was being absorbed into solution, its activity would decrease over time D. To see if polyphenol oxidase was an induced defense that can change its expression over time (i.e., 5 minutes).

B.

In the SimUText section on Physiological Ecology, you learned about how climate limits the distribution of red spruce (Picea rubens) in North America. Why is red spruce NOT found in Arizona? A. In Arizona, there are some months when precipitation is more than potential evapotranspiration (PET). B. In Arizona, there are some months when precipitation is less than potential evapotranspiration (PET). C. In Arizona, there are some months when temperatures fall below freezing. D. According to Liebig's Law of the Minimum, red spruce is limited by the scarcest resource in Arizona.

B.

Ronald A. Fisher reasoned that self-fertilizing individuals (selfers) enjoy a 3:2 gene transmission advantage over cross-fertilizing individuals (outbreeders). If this is true, why don't all hermaphrodite organisms become selfers? A. The 3:2 advantage does not hold for outbreeders that mate with many partners. B. Many organisms outbreed because the level of inbreeding depression resulting from self-fertilization outweighs the gene transmission advantage. C. Many organisms cross-fertilize because Fisher's reasoning was flawed, as Agrawal later showed by demonstrating that sexual individuals also enjoy a transmission advantage. D. Many organisms outbreed because asexual reproduction is less costly than sexual reproduction.

B.

Studies of the apply maggot fly (Fhagoletis pomonella) demonstrate that speciation: A. Occurs only when there is complete geographic isolation B. Can be driven by divergent adaptation C. Primarily involves mechanisms of post-mating isolation D. Prevents the proper functioning of zygotes in hybrids

B.

Suppose that a population of plant species is subdivided into small patches. Which of the following factors would tend to decrease genetic variation WITHIN each patch, but increase genetic differentiation AMONG patches? A. Recombination B. Genetic drift C. Mutation D. Migration

B.

Suppose that you could enlarge an organism without changing its proportions; that is, it would retain the same shape and the same composition. If you enlarged it so that its mass doubled, what would happen to its surface-area-to-volume ratio? A. It would be unchanged B. It would decrease C. It would increase, but by less than a factor of 2 D. It would increase, but by more than a factor of 2

B.

The theory of evolution is now an accepted fact for virtually all scientists. What was the most important contribution that Alfred Russell Wallace made to the understanding of evolution? A. He proposed that evolution depended on phenotypic variation. B. He proposed that natural selection was the mechanism causing evolutionary change. C. He confirmed Mendel's Laws by crossing plants with different phenotypes. D. He demonstrated that species arose more commonly on isolated islands than on continents.

B.

Two species are found that are similar in appearance (i.e., phenotype) and in habitat preference, but they cannot interbreed. Which species concept is MOST relevant to defining them as separate species? A. Morphological B. Biological C. Phylogenetic D. Ecological

B.

What is NOT a possible outcome of the Lotka-Volterra competition model? A. Species 1 outcompetes Species 2. B. Both species stably co-exist with their population sizes remaining above K. C. Species 2 outcompetes Species 1. D. Species 1 or Species 2 wins out, depending on the initial advantage.

B.

What is NOT a prediction of the theory of evolution by natural selection? A. The observance of natural selection acting in the wild B. The discovery of fossils resembling modern day organisms and fossils resembling ancient organisms in the same layers of rock C. The existence of genetic variation for many traits D. The discovery of fossils that link together groups of species that are known to have common ancestry

B.

What is NOT an adaptation for desert plants? A. Reduced surface area of the leaves B. Increased numbers of stomata C. CAM physiology D. Thick waxy cuticle covering the epidermis

B.

What would happen if Earth's axis of rotation were tilted at a lesser angle (e.g., 10 instead of 23.5 degrees) toward/away from the Sun? A. Seasons would be more pronounced. B. Seasons would be less pronounced. C. There would be no difference in average temperature between the poles and the Equator. D. Nothing would change.

B.

Which of the following concepts and observations did NOT influence Darwin in developing the theory of evolution by natural selection? i. The variety of domesticated species that had been produced by artificial selection. ii. Inheritance follows the laws of segregation and independent assortment. iii. Human populations tend to multiply more rapidly than food supplies. iv. Geological change is sudden, short-lived and punctuated by large periods without change. v. Fossils in younger strata resemble living species more than fossils in older strata. A. i, iii B. ii, iv C. i, iii, v D. ii, iii, iv

B.

Which of the following factors may explain why there are sometimes different biomes at the same latitude? i. Ocean currents ii. Location and size of mountain ranges iii. The Coriolis effect A. i, ii, iii B. i, ii C. ii, iii D. i

B.

Which of the following ideas are common to both Darwinian and Lamarckian evolution? i. All species can change over time. ii. All species existing today share a common ancestor. iii. Offspring inherit many of their characteristics from their parents. iv. Inheritance involves passing information from somatic cells to offspring. v. Organisms always evolve towards larger body sizes. A. i, iii, v B. i, iii C. ii, v D. i, ii, v

B.

Which of the following is NOT a component of the theory of evolution by natural selection? A. A species undergoes genetic change over time. B. Only natural selection can cause evolutionary change. C. All species alive today can be traced back to a single common ancestor. D. Major evolutionary changes usually occur over many thousands of generations.

B.

Which of the following is NOT an advantage of sexual reproduction? A. Quick purging of deleterious alleles from the genome B. Passing on 100% of an individual's genome to the next generation C. Faster evolution to counter parasites D. Recombination leading to adaptive gene combinations

B.

Which of the following is a characteristic shared by almost all native species of oceanic islands? A. They have wings. B. They can colonise through long-distance dispersal. C. They multiply quickly. D. They do not compete with each other for resources.

B.

Which of the following models and parameter values predicts that a population will decline to extinction? A. Exponential growth, r = 0.4 B. Exponential growth, r = -0.4 C. Geometric growth, λ = 1.2 D. Logistic growth, r = 0.4, K = 1000

B.

Which of the following statements about meiotic drive is FALSE? A. It leads to a significant departure from the expected 50:50 ratio of allele representation in gametes. B. Because it often reduces the fitness of individuals, it cannot spread through a population. C. Restorer alleles often spread elsewhere in the genome to prevent it. D. It demonstrates gene-level selection.

B.

Which of the following statements about the Galapagos Islands is FALSE? A. The islands are a series of islands that are volcanic in origin. B. Species found there experience high gene flow with mainland populations. C. The islands are relatively young on an evolutionary timescale. D. Darwin's finches experienced rapid adaptive radiation to distinct environments.

B.

Which of the following statements about the evolution of olfactory receptor genes is FALSE? A. In the human genome, many olfactory receptor genes represent an example of vestigial genes. B. Species with more functional olfactory receptor genes rely more on colour vision. C. Humans have a relatively high proportion of inactivated olfactory receptor genes. D. Mice have a relatively low proportion of inactivated olfactory receptor genes.

B.

Which of the following statements about using a spectrophotometer to measure absorbance is CORRECT? A. The spectrophotometer is calibrated (blanked) with an empty cuvette in the compartment. B. The same cuvette should always be used to both blank the spectrophotometer and measure the absorbance of the sample. C. The spectrophotometer is blanked to make sure that the absorbance of only the solvent is being measured. D. Absorbance specifically measures how much light passes through the sample.

B.

Which of the following statements best describe the difference between a polygenic trait and a Mendelian trait? i. Polygenic traits are rarely involved in adaptation. ii. Mendelian traits commonly show discontinuous variation. iii. Polygenic traits are more strongly influenced by the environment. iv. Mendelian traits are usually governed by one or a small number of genes. A. i, iv B. ii, iii, iv C. i, ii, iii D. ii, iv

B.

Which of the following statements is INCORRECT according to the biological species concept? A. Closely related species can often hybridize to produce unfit offspring. B. Species are always morphologically very distinct from one another. C. Species are the units of evolution. D. Gene flow between species is limited by isolating barriers

B.

Which of the following traits are MOST useful for constructing phylogenetic trees? i. Homologous traits ii. Convergent traits iii. Shared, derived traits iv. Polymorphic traits A. i, ii B. i, iii C. ii, iii D. iii, iv

B.

Which statement best describes why vestigial characters provide important evidence for evolution? A. They demonstrate the importance of inbreeding on fitness. B. They show signs of modification or loss of an original function. C. They demonstrate adaptive radiation on islands. D. They provide compelling evidence for hybridization among species. E. They provide clear cases of transitional forms in the fossil record.

B.

You discover a new oceanic island and find that it has many species of birds. What will you most likely discover about these species? A. They occupy the same ecological niches. B. They are closely related to a bird species on the nearest mainland. C. They evolved from independent colonisations of the island. D. They compete with other island species for resources.

B.

ΨGLU is a famous example of a human pseudogene. Why is it no longer needed? A. Humans consume less cellulose than their primate relatives and recent common ancestors. B. Humans obtain enough vitamin C through their diet. C. Modern humans are rarely subject to parasites. D. Smallpox has been eradicated.

B.

Tradeoffs

Balance achieved by two desirable but incompatible features (look up in the book) - Many structures represent a compromise between functions

Food webs of tundra biome

Based on grazing mice - active all year round - prayed by carnivores: weasels artic foxes, snowy owls - population fluctuate Based also migratory geese and caribou

Small-scale variation

Biomes subdivided into habitats- habitat level variation Other factors: - Animal behavioral choices ''habitat selection'' - Some animals exhibit extreme habitat selection for no apparent reason: habitat specialist -

relative heat transfer

Bodies emit Electromagnetic thermal radiation - Net changing heat experience depends on net difference between energy being radiated outward and the amount being radiated towards

Other adaptations for desert plants

Bone dry except 1-2 times a year/ water conservation adaptation: Ex: giant saguaro cactus - internal water storage - very extensive shallow root system sucks up water as it falls - the accordion pleated stem that allows it to expand w/o bursting - desert annual plants have compressed life cycle - seeds germinate right after it rains - grow, flower, set seed, die within 2 months - temporarily evade desert conditions by growing during brief rainy periods Woody shrubs/trees exhibit microphyll (tiny leaves) - don't expose large photosynthetic areas to the sun, arranged for turbulent air flow - leaves are thick= thermal inertia - some evergreen some deciduous - some have green photosynthetic bark - leaves = thorns

E.B. Ford

British ecological geneticist, leader among those British biologists who investigated the role of natural selection in nature

In a forest succession we can distinguish transitional seral stage from a stable climax

By comparing species composition of mature canopy trees to young saplings in the understory Stable climax: same species, the tree species are capable of reproducing under their own shade

A colleague shows you beetle specimens from two different populations. You suspect that they might be two different species. Which of the following observations would provide strong evidence that they are two different species according to the biological species concept? A. The two populations have very different body colouration patterns. B. The two populations have different food sources. C. Individuals from the two populations produce sterile progeny when mated. D. The two populations were collected from different areas of the world.

C.

A population of beetles live and feed mainly on green leaves when they are adults. These beetles have green coloration on their thorax and abdomen. In which scenario is the green colouration of these beetles MOST LIKELY to continue to evolve by natural selection? A. All individuals in the population have the same amount of gren colouration on their thorax and abdomen. B. The amount of green colouration per individual is determined by the environment only. C. Individuals with a greater amount of green colouration are less likely to be eaten by birds. D. This species of beetle reproduces asexually.

C.

According to Chapter 3 of the lab manual, what is the MOST ACCURATE definition of plant defense? A. a plant's ability to resist herbivores B. a plant's ability to reduce the effects of herbivory on fitness C. a plant trait that reduces damage by herbivores D. all of the above

C.

According to Chapter 7 of Coyne's "Why Evolution is True", which of the following statements about the theory of geographic speciation is FALSE? A. The theory proposes that geographic isolation is the first step in speciation. B. The theory predicts that there should be a positive correlation between the time of geographic separation and the amount of reproductive isolation. C. On island archipelagos, the theory predicts that the most closely related species should be found on the same island, rather than different islands. D. Reproductive isolation under this theory occurs as a by-product of ongoing evolution in isolated populations.

C.

An imaginary genus of terrestrial mammals contains several species that occur in places ranging from hot tropical to cold subartic climates. Which of the characteristics below would you expect to find in the species that has its veins and arteries very well separated in its paw pads (i.e., a species lacking countercurrent circulation)? A. The species with the longest fur B. The species with the largest body mass C. The species with the highest surface area to volume (SA/V) ratio D. The species with the smallest ears

C.

An organism's "sexual system" refers to which aspect of its reproductive diversity? A. The extent to which is reproduces clonally or sexually B. The importance of cross- vs. self-fertilization C. Whether the sexes are combined or separated in individuals D. Whether or not inbreeding depression arises from self-fertilization

C.

Brassica rapa is an annual plant that produces hundreds of seeds in the single year of its lifespan. Only a few seeds survive to become reproductive adults. Based on this information, what type of survivorship curve would you expect most B. rapa populations to exhibit? A. Type I survivorship curve B. Type II survivorship curve C. Type III survivorship curve D. Type IV survivorship curve

C.

Chemosynthetic organisms found in deep ocean hydrothermal vents: A. Are close relatives of the first life on earth B. Only derive carbon from their symbiotic partners C. Evolved from shallow water species D. Can survive in both deep sea and shallow habitats

C.

Darwin noted that the crust of Earth is like a museum where the collections have been made at remote locations and time points. What contributes to the incompleteness of the fossil record? A. Soft body parts are more likely to fossilize than hard parts. B. Most species that fossilize are small. C. Marine organisms are more likely to fossilize than terrestrial organisms. D. Only carnivorous species fossilize.

C.

For a species with two sexes, which of the following would you expect from the sex who produces gametes that are rich in nutrients and provides parental care? A. Production of a very large quantity of gametes B. Evolution of exaggerated traits C. Being choosy in picking mates D. Physical competition to win matings with the opposite sex

C.

Heterozygous individuals for a particular allozyme locus (FS) were found to have higher fitness than either of the two homozygous genotypes (FF or SS). Which of the following statements is CORRECT? A. Heterozygosity will be eliminated from the population due to positive selection. B. Heterozygosity will increase over time through random genetic drift. C. Heterozygosity will be maintained in the population because of natural selection. D. Heterozygosity will only persist if there is gene flow from other populations.

C.

In Chapter 1 of Coyne's book he points out that although speciation was important for Darwin's ideas, he did not explain in the "Origin of Species" how new species actually arise. Why was this? A. Darwin had difficulty in defining species. B. Darwin believed that adaptation was necessary for speciation. C. Darwin lacked an understanding of genetics. D. Darwin failed to appreciate the importance of coevolution.

C.

In Lecture 13, Professor Frederickson explained how interactions with nitrogen-fixing bacteria called rhizobia have contributed to the global spread of invasive legume species. What was the main result of her research? A. Depending on bacteria for nitrogen limits the spread of legumes around the world. B. Legumes rarely invade new regions. C. Partnering with many different types of rhizobia helps legumes spread to more new regions. D. The spread of invasive legume species is limited by temperature and precipitation.

C.

In one of the experiments in the Brandt and Mahsberg (2002) article, nymphs from the three experimental groups were placed near an ant trail and the researchers recorded the response of the ants to the nymph. Which of the following statements about this experiment is CORRECT? A. The dependent variable is the kind of ant the nymphs were exposed to. B. The independent variable is whether the ants attacked or ignored the nymph. C. The null hypothesis is that the amount of cover on the nymphs (e.g., backpack and/or dustcoat) does not affect the response of ants to the nymph. D. If the nymphs with a dustcoat and a backpack are attacked more than the naked nymphs, then the null hypothesis is not rejected.

C.

In the Levin's model of patch occupancy in a metapopulation, colonization of patches is affected by: i. The fraction of occupied patches, P ii. The fraction of empty patches, 1-P iii. The extinction rate, e A. i only B. ii only C. i, ii D. i, ii, iii

C.

Keystone predators maintain species diversity in ecological communities by: A. Excluding superior competitors within their own trophic level B. Causing selection for superior defensive traits in prey C. Preying on the most competitive species at lower trophic levels D. All of the above

C.

On what fact did Darwin base his prediction that fossils of early humans would be found in Africa? A. His contemporaries had found remains of very ancient tools in Africa. B. The warm climate in Africa is ideal for the evolution of hairless apes. C. The closest evolutionary relatives of humans are found in Africa. D. Only an origin in Africa would be able to explain the present distribution of humans on Earth.

C.

Researchers surveyed multiple populations of a species of grass, and found that plants in the drier environment grew thicker leaves than plants from the wetter environments. A transplant experiment shows that plants from the wet environment grow thick leaves when grown in the dry habitat. Which of the following phenomena can explain this result? A. Gene flow B. Local adaptation C. Phenotype plasticity D. Genetic drift.

C.

Sugar gliders are marsupials. Flying squirrels are placentals. yet they are phenotypically very similar. This is an example of: A. A shared recent common ancestor B. Phenotypic traits that have a very simple genetic basis C. Convergent evolution D. Abundant gene flow between the species

C.

The Polar Cells create what kind of climate at the North and South Poles? A. A hot climate with little precipitation B. A hot climate with a lot of precipitation C. A cold climate with little precipitation D. A cold climate with a lot of precipitation

C.

There are two alleles (A1 and A2) at a locus of a population. This population is in Hardy-Weinberg equilibrium at this locus. If 81% of the individuals in the population are A1A1 at this locus, what is the frequency of the A1 allele? A. 0.9 B. 0.09 C. 0.1 D. 0.01

C.

What is an adaptive radiation? A. Independent evolution of similar traits in different species B. Evolution of an increased mutation rate in organisms subject to radiation C. Rapid speciation in response to a new environment D. Adaptive reversion back to an ancestral trait

C.

What is one reason that a species has a small geographic range? A. The species disperses easily to new habitats B. The species tolerates a broad range of climatic conditions. C. The species is overly specialized on a mutualist. D. The species is extinct.

C.

What is the difference between genetic drift and natural selection? A. Natural selection causes changes in gene frequency over time while genetic drift does not. B. Natural selection raises the frequency of beneficial alleles, while genetic drift raises the frequency of harmful alleles. C. Natural selection changes the frequency of alleles based on how beneficial they are whereas genetic drift changes the frequency of alleles regardless of how beneficial they are. D. Genetic drift is responsible for the evolution of simple phenotypic variation (such as coat colour) whereas natural selection is responsible for the evolution of complex traits (such as the eye).

C.

What was a key conclusion from Thomas Park's experiments using flour beetles? A. Abiotic conditions are typically unimportant for the outcome of biotic interactions B. Outcomes of species competitions are independent of the starting number of each competing species. C. Two species occupying the same niche cannot co-exist indefinitely. D. Lotka-Volterra models cannot explain interactions between real organisms.

C.

Which environment is expected to have the largest/most complex vegetation? A. Dry and warm B. Dry and cold C. Wet and warm D. Wet and cold

C.

Which of the following comparisons of latitudinal features is TRUE? A. The Intertropical Convergence Zone is located further to the north in January than it is in July. B. Westerly winds prevail around 40 degrees north latitude, but in the southern hemisphere, the equivalent latitude (40 degrees south) is characterized by the easterlies ("the roaring forties"). C. The doldrums and the horse latitudes share the characteristic of having weak, inconstant, and unreliable winds. D. The Coriolis Effect works in opposite directions in the northern and southern hemispheres, causing easterly trade winds north of the equator and westerly trade winds south of the equator.

C.

Which of the following does NOT tend to increase genetic diversity within populations? A. Mutation B. Recombination C. Negative selection D. Heterozygote advantage

C.

Which of the following is NOT a characteristic of a theory? A. A theory is testable. B. A theory makes predictions that can be verified using the scientific method. C. One experiment is enough to completely prove or disprove a theory. D. A theory is tested against alternative theories.

C.

Which of the following is NOT a factor that INCREASED a population's risk of extinction following a severe environmental change? A. Small population size B. High rate of inbreeding C. High beneficial mutation rate D. Alleles that are beneficial after habitat change were previously deleterious

C.

Which of the following is NOT required for adaptations to evolve? A.Heritable variation in fitness B. Genetic diversity within populations C. Sexual reproduction D. Natural Selection

C.

Which of the following is one reason why herbivorous mammals and carnivorous mammals have different gut microbiomes? A. Only carnivores depend on microbes to detoxify plant secondary chemicals B. All herbivores have a rumen where microbes ferment plant material C. Only herbivores depend on microbes to digest cellulose and lignin in plant cell walls D. Gut microbes are vertically transmitted in herbivores, but horizontally transmitted in carnivores

C.

Which of the following statements about adaptations is CORRECT? A. Adaptations occur due to the random effects of natural selection. B. Adaptations always increase the fitness of the species. C. Adaptations can occur step-by-step, with each step needing to increase the fitness of the individual. D. Adaptations evolve by increasing the longevity of the individual.

C.

Which of the following statements about compound microscopes is CORRECT? A. You should use only the coarse adjustment knob to focus on a specimen when you are viewing it through the highest objective lens. B. There should be a coverslip on your slide only when you are using the lowest objective lens. C. You can calibrate an ocular micrometer by using a stage micrometer since the stage micrometer is of a known distance (e.g., 1 mm). D. As magnification increases, the size of the ocular unit increases.

C.

Which of the following statements about mutations is FALSE? A. The environment can influence the rate of random mutation. B. Mutation rates at any base of DNA are low, but each of us has on average multiple new mutations in our genome. C. Organisms induce adaptive mutations when they are subject to stress. D. Mutations are more likely to be deleterious than beneficial.

C.

Which of the following statements about sympatric speciation is TRUE? A. It is thought to be the most common mode of speciation. B. It is more common in animals than plants. C. It is thought to occur rarely, with the exception of polyploid speciation. D. It is more common in the fossil record than in the present.

C.

Which of the following statements about the series of numbers below is INCORRECT? 9, 5, 8, 6, 10, 9, 8, 9 A. The mode is 9 B. The range is 5 C. The median is 9 D. The mean is 8

C.

Which of the following statements is CORRECT? A. Species evolve only by natural selection. B. A trait that increases an individual's chances of survival will always lead to increased fitness. C. For natural selection to act on a trait, there always needs to be variation of the trait within a population. D. An individual can adapt to any environment by changing its phenotype.

C.

While on the voyage of the Beagle, Darwin observed fossils of giant armadillos. How did this observation provide a useful line of evidence for the process of evolution? A. It showed that species generally evolve to be smaller over time. B. It showed that transitional forms are not the direct ancestor of modern species, but only closely related lineages. C. It showed that extinct species often resemble, with modification, organisms living nearby. D. It showed that the inheritance of acquired characters was not possible.

C.

Why is ecological niche modelling useful? A. Ecologists can use known ecological conditions, such as temperature and precipitation, to predict the ecological conditions of an unexplored region. B. Because ecologists know that a species will not occur outside the core area of its ecological envelope, they do not have to look for it there. C. Ecologists can use a species' ecological envelope to predict where a species may occur more broadly. D. Because ecological conditions are very stable, ecologists can use a species' ecological envelope to define a species' realized niche.

C.

Ford and Dobzhansky

Came up with the balance school.

Morgan & Muller

Came up with the classical school

Fisher

Came up with the fundamental theorem. Co-provided foundations for "Neo-Darwinism" and "New Synthesis". Disagreed and argued against Wright that most evolution occurred in large populations by natural selection.

Lewontin

Came up with the idea of electrophoresis to further analyze DNA and its proteins.

Bradshaw

Came up with theory of evolution of heavy metal tolerance in plants

Herbaceous plants

Capable of being burned to the ground the resprouting quickly from underground buds

tertiary producers/ secondary consumers

Carnivores= trophic level 3

Seasonal variation in climate

Caused becaus earth's axis tilted about 23.5˚ off the vertical - During it's annual revolution, different parts of earth experience the sun as being directly overhead at noon - Annual shifts in angle are gradual but their effects on day length and heat input are profound - Latitudinal lines at 23.5˚N= tropic of cancer and 23.5˚S- Tropic of capricorn (belt by them called "tropical region" - Solar light transfers heat to the earth

Secondary compounds/ metabolites

Chemicals with no role in basic photosynthesis, respiration or maintenance - Many of them have potent effects on metabolisms of animals that ingest them - Used as medicines, spices, drugs - Alkaloids - Defence against herbivores is the main function -contribution to plant survival and fitness is crucial - lack of protective chemicals = susceptibility to attack

Trophic structure

Community organization based on the ways species - all organisms occupy a trophic position within the food web of a community

Soils

Complex mixtures of inorganic breakdown products of rock + organic matter

Omnivores:

Consume from more than one trophic level = Plants and animals

Soil characteristics

Contribute strongly to differences among biomes. Type of soul is critical to: - Whether that water is available to organisms -what mineral nutrient it contains Soil influences vegetation and vice versa

Third set of annuals

Crop plants: - particularly rice, maize and wheat - are annuals bc of artificial selection by humans *maximizes seed output, allow regular cultivation of the soil - long-lived semelparous perenniality can be an advantageous strategy due to animal pollinators of such plants may have been disproportionately attracted to visit the plants with the largest inflorescences

Other organisms produce few but strong offspring

Curve initially descends more gradually

A researcher discovers a new phenolic compound (a chemical) in a species of plant. She hypothesizes that this chemical defends the plant from attack by herbivores. What is the BEST way for her to test this hypothesis? A. To test whether the amount of chemical produced by the plant affects the amount of damage to the plant by herbivores B. To test whether the damage to the plant by herbivores affects the amount of chemical produced by the plant C. To test whether the amount of chemical produced affects the fitness of the plant (i.e., the amount of seeds it produces) D. To test whether the chemical is produced in the absence of herbivores

D.

Autumn temperatures at northern latitudes have increased by 1.1 degrees Celsius over the past two decades and continue rising. Based on what you read in the Lab Girl excerpt, how might this warming trend affect the ability of plants to tolerate below freezing temperatures? A. Plant tolerance is reduced because there is insufficient time for hardening to occur before winter B. Plant tolerance is greater because winters are milder and growing seasons are longer C. Plant tolerance is unchanged because sugars, proteins and acids are present in plant cells year-round D. Plant tolerance is unchanged because hardening is cued by photoperiod, not temperature

D.

Based on Chapter 2 of Coyne's Why Evolution is True, which of the following statements about 'missing link' species is CORRECT? A. They have been commonly found in the fossil record. B. They are expected to look very different from transitional forms in the fossil record. C. They will always look halfway between two modern-day species. D. They represent the common ancestral species of two species living today.

D.

Complete the sentence: Protists residing in the intestines of termites A. produce enzymes used by termites to synthesize amino acids B. are parasites that reduce the reproductive potential and survival of termites C. protect termites exposed to harmful bacteria in rotting wood D. aid in the digestion of cellulose and other complex molecules

D.

Imagine a population of marine iguanas that breeds once a year, lives on a large island with unlimited resources, and has no competitors or predators. The growth of this population over a year is BEST modelled by which of the following equations? A. dN/dt = rN B. dN/dt = rN(1-(N/K)) c. dN(1)/dt = r(1)N(1)(1-(N(1)/K(1))-((a(12)N(2))/K(1))) D. N(t+1) = λN(t)

D.

Imagine you are a scientist interested in finding out how a fish population will respond to climate warming. You keep the fish in aquaria at two different temperatures: fish in Group 1 are kept at a water temperature that is 10 C warmer than fish in Group 2. If the fish CANNOT acclimate to warmer temperatures, you would expect: A. Group 2 fish to tolerate higher temperatures than Group 1 fish B. Group 1 fish to tolerate higher temperatures than Group 2 fish C. Group 1 fish to adapt more rapidly to high temperature than Group 2 fish D. Group 1 fish to have the same high temperature tolerance as Group 2 fish

D.

In Lecture 14, Professor Frederickson described how ecological niche modelling can be used to predict how the range of Plasmodium falciparum, a parasite that causes malaria, will shift in response to climate warming. Which of the following are important niche axes for Plasmodium falciparum? A. temperature and precipitation B. Soil type C. Temperature, precipitation, and soil type D. Temperature, precipitation, and Anopheles mosquito density

D.

In one species of butterfly, females are attracted to males with blue patches on their wings. If females were choosing males according to sensory-bias models, which of the following would you expect? A. Males with brighter blue patches provide more parental care. B. Males with the brightest patches pass on the genes resulting in higher offspring fitness. C. Males with the brightest blue patches are least likely to have parasites. D. No correlation between the brightness of blue patches and offspring fitness or survival.

D.

Lying roughly between 20 and 30 degrees south in latitude, the Atacama Desert in Chile is the driest hot desert in the world with some areas having never recorded rainfall. The driest portion of this desert covers a 1000 km strip of land east of the Andes and west of the Chilean Coastal mountain ranges (i.e., between these two mountain ranges). Which of the following factors does NOT contribute to these inhospitable conditions? A. The driest part of the desert is located in a rain shadow. B. There is a cold ocean current off the west coast of Chile. C. Dry air descends at roughly 30 degrees south in latitude. D. The sun is directly overhead all year.

D.

Madagascar Hissing Cockroaches get their name from the hissing sound they produce. How does this trait affect an individual's chances of survival and/or reproducing? i. It scares predators. ii. It attracts prey (e.g., small insects and other arthropods). iii. It attracts mates. iv. It intimidates competitors for mates. A. ii, iii B. iii, iv C. i, iv D. i, iii, iv

D.

Natural populations are typically below K because: A. Many species have overlapping generations. B. Natural enemies act in density-independent ways. C. Pathogens are rare in nature. D. Few species have no natural enemies.

D.

Quagga mussels have a lower level of heterozygosity than zebra mussels. What does this suggest about the source and founding populations of quagga mussels in Lake Ontario? A. The founding population of quagga mussels consisted of all homozygotes. B. The source population of quagga mussels had low heterozygosity. C. The founding population of quagga mussels was much smaller than the founding population of zebra mussels. D. Both b and c.

D.

Several explanations for sexual dimorphisms are discussed in Chapter 6 of Coyne's Why Evolution is True. Which mechanism explains the evolution of sexual dimorphism when females derive no direct or indirect benefit from mating with certain types of males? A. Females prefer to mate with males that will provide food. B. Females prefer to mate with males that have good genes conferring high fitness in the offspring. C. Males with showy traits are more susceptible to predation. D. Females prefer to mate with males exhibiting traits for which they have a pre-existing sensory bias.

D.

Species are not perfectly designed for their environments as would be expected if they were created from scratch by a designer. Which of the following is NOT an explanation for this fact? A. Organisms are constrained by their development and evolutionary history. B. Adaptations for one aspect of an organism's life might interfere with an adaptation for another aspect. C. The genetic mutations that give rise to new adaptations might not have occurred or have been very rare. D. Natural selection favours deleterious mutations that interfere with the perfect design of a species.

D.

What have the studies of evening primrose (Oenothera) revealed about the evolution of asexual reproduction in this system? i. Asexuality has evolved multiple times independently across the phylogeny. ii, Asexuality is associated with larger genomes. iii, Asexual genomes have more harmful mutations than sexual genomes. iv. Asexuality cannot evolve. v. Constant environments select for asexuality. A. ii, iv B. i, ii C. i, v D. i, iii

D.

What is a "transitional species"? A. An ancestral species B. A hybrid between two now extinct species C. A species living both on land and in water D. A species showing a mixture of traits from species that lived both before and after it

D.

What is the BEST definition of a vestigial trait? A. A trait that has disappeared from a population B. A trait that originally had a function but no longer has any function C. A trait that has evolved many functions D. A trait that no longer performs the function for which it evolved

D.

What is the BEST definition of phenotypic plasticity? A. One phenotype that is produced by various genotypes in response to changes in its environment. B. A phenotype that can respond in the next generation to changes in its current environment. C. A phenotype that is capable of change. D. One genotype that can produce various phenotypes in response to changes in its environment.

D.

What is the Green World Hypothesis of Hairston, Smith, and Slobodkin (HSS)? A. Population sizes are mostly controlled by physical conditions like weather B. Population growth is mostly limited by resources C. Herbivore populations are food-limited D. Herbivores do not eat all the plants in the world because predators regulate herbivore population sizes

D.

What is the main defining characteristic of savannah vegetation? A. Short grassland on low nutrient soils B. Tall grassland on hydric soils C. Continuous canopy of deciduous trees D. Discontinuous canopy of scattered trees

D.

What typically is the air in the intertropical convergence zone (ITCZ)? A. Sinking B. Rather stationary C. Rising and sinking at equal rate D. Rising

D.

Which is NOT a mechanism to prevent inbreeding depression in flowing plants? A. Self-incompatibility systems B. Producing separate male and female flowers C. Changing the timing of reproduction for male and female function D. Reducing flower size and distance separating sex organs

D.

Which of the following factors are important for understanding why adaptive radiations occur on islands? i. Relatively few species reach the island, and there is low migration from the mainland. ii. Severe population bottlenecks reduce diversity within island species. iii. Inbreeding depression can be severe on islands, favouring outcrossing. iv. Island archipelagos have diverse environmental conditions. v. Many species on islands show vestigial traits. A. i and iii B. i and v C. ii and iv D. i and iv E. i, iv, and v

D.

Which of the following groups of organisms would the biological species concept NOT apply to? A. Insects B. Plants C. Mammals D. Bacteria

D.

Which of the following statements about Darwin's and Lamarck's theories of evolution are CORRECT? i. Although Darwin and Lamarck disagreed about the mechanism of evolution, they both agreed that all organisms living today share a common ancestor. ii. Lamarck believed that there was an inherent tendency towards increasing complexity. iii. Both Darwin and Lamarck believed there was an important role for the environment in driving evolutionary change. iv. Darwin believed that all adaptations spread to increase the fitness of species, while Lamarck believed adaptations were for the benefit of the individual. v. Lamarck believed that frequent spontaneous generation of new organisms, rather than speciation, explained species diversity. A. i and iii B. ii and iv C. ii, iv and v D. ii, iii and v E. i, iii and v

D.

Which of the following statements about the G6PD deficiency polymorphism in human populations is CORRECT? A. The deficiency allele is maintained by mutation-selection balance. B. The deficiency allele has become common due to founder events. C. Gene flow has caused the deficiency allele to become very common in Africa. D. The deficiency allele has experienced recent positive selection in Africa.

D.

Which of the following statements about the difference between continuous and discrete traits is TRUE? A. Continuous traits follow the rules of blending inheritance, while discrete traits follow Mendelian inheritance. B. Mendel's experiments focused on continuous traits and not discrete traits. C. Variation at discrete traits, but not continuous traits, typically has a major environmental component. D. Measuring genetic diversity for continuous traits involves artificial selection experiments, while for discrete traits it can involve tracking polymorphism and heterozygosity.

D.

Which of the following statements concerning the Brandt and Mahsberg (2002) study on West African assassin bug nymphs is CORRECT? A. Only the dust coat aids in avoiding recognition by predators. B. Only the backpack aids in avoiding recognition by predators. C. Both the dust coat and backpack aid in avoiding recognition by prey. D. Both the dust coat and backpack aid in avoiding recognition by predators.

D.

Which of the following statements is FALSE? A. In deciduous forests, most consumption of living leaf material is by insects. B. Boreal forests have poor soil compared with temperate deciduous forests. C. Most tropical plants are pollinated by animals. D. Most flowering in tropical deciduous biomes occurs during the wet season.

D.

Why is penicillin rarely used to treat staph infections? A. The patient's body eventually habituates to the antibiotic and it no longer works. B. Most people have developed their own immunity to staph infections so the drug is no longer needed. C. Scientists have developed new antibiotics against staph infections that have less adverse effects than penicillin. D. Most strains of staph bacteria have evolved resistance to penicillin.

D.

Majerus

Deduced that Kettlewell's case was of rapid evolution, probably involving pollution and bird predation

Best agricultural soils

Deep, black, organic rich mesic loams

Atmospheric circulation

Delivery of solar-derived heat to the bottom of the atmosphere has consequences: - Analogy: water convection - creates atmospheric circulation patterns - violent chaotic overturn on the earth's atmosphere, manifested as immensely energetic storm systems - Consequences of large-scale patterns more important but very predictable

Thermoregulation and osmoregulation

Depend on body size +shape Most important aspect of the body= ratio of surface area to volume (SA/V) - When organism small, its SA/V ratio is high: any heat generated is sucked away EX: Pramecium * can get away with being a themoconferm (body temp changes accordingly with environment) * osmoregulation is imperative: if flow cant be countered cells burst * Contractive vacuole- requires expending energy to counteract inward pressure= active regulation Exeption: insects can be thermoregulators if large enough, have access to high energy food and have insulation

Ectotherms

Depend on heat from the environment

Animal behavioral choices ''habitat selection''

Depend on particular plant species or plant communities for food/habitat Ex: in Sonoran Desert: woodpeckers vacate nests they created and owls take over. Owls choose to avoid non-desert habitats as unsuitable bc these leftover nest are a critical resource.

Habitat level variation

Depends on smaller scale differences than regional climate

Agrawal

Did an experiment to show the pros and cons of a species reproducing sexually and asexually in a certain environment (ergo: homogenous, heterogeneous)

Hoekstra

Did an experiments on coats of rats to see if this affected predators and habitats.

McClintock

Discovered "jumping" genes or transposable genetic elements in maize. Won Nobel Prize.

What is a discrete trait?

Discrete, or discontinuous, traits are controlled by a small number of genes, often only one. These genes generally have two alleles. For instance, Mendel's pea seeds had two alleles for shape: smooth or wrinkled.

Intermediate disturbance hypothesis

Diversity is enhanced when disturbance is neither too common nor too rare. Succession: it is a diverse collection of outcomes that emerge from interacting properties of climates, soils and organisms.

R-selected species

Do well in low-density situations

Which statement about macroevolution is CORRECT? A. Organisms further to the left on a phylogenetic tree are typically more evolved forms. B. Organisms further to the left of a phylogenetic tree represent common ancestors of species living today. C. Species living today that show more changes from an ancestral form have had more time to evolve than species living today with fewer changes. D. The fossil record indicates that chimpanzees are our most recent ancestors. E. Moving down a phylogenetic tree is equivalent to going backwards in time.

E.

herbivorous insects

Eat 1 kind of plant bc they can overcome that plants chemical defences in both cases as before: predators fate is tied to a single resource population

Endothermy vs Ectothermy

Endothermy: dependant on internal generation of heat Ectothermy: Dependent on external sources of body heat Temperature is primarily determined by physiological processes acting within the body

Charles Darwin

English natural scientist who formulated a theory of evolution by natural selection

Hydric soils

Enriched with aluminum and iron

Hadley cells Set prevailing winds in motion + affect precipitation profoundly

Equatorial tropical regions are very rainy: - air that goes into ITCZ is, humid, heavy and laden w/ water vapor as it rises+ cools water vapor condenses into liquid water and falls as rain - Air returning to ITCZpicks up moisture from the ocean+wetter tropical regions

A few aspects of life history evolution

Evolutionary ecology ecological circumstances that drive selection for life history characteristics like lifespan, age of first reproduction, number and timing of offspring - Ecology drives adaptive evolution in timing characters also in physiological and morphological characters

The difficulties of herbivory as a factor in the generation of biodiversity

Evolutionary ecology of plant-animal interactions and plant-herbivory relationships - A diet of plants requires elaborate adaptations, bc plants have evolved to defend the important tissues to their fitness (make it unpalatable) - This is true for folivory - Some plant tissues are not defended (fruit, nectar), their adaptive function is to be eaten

Animals adapted to deserts= spectacular adaptations for conserving water

Ex kangaroo rats - can survive w/out drinking water - seeds they eat have small amounts of water - subsist on "metabolic water" produced by oxidizing the dry food they eat - bipedal habit reduces the amount of conductive heat gained from hot sand - Extremely efficient kidneys - Nocturnal - Underground burrows - seeds are hygroscopic= absorb moisture

Evolutionary constraint

Ex: resource allocation tradeoffs: reduce the range of kind of adaptation that one might otherwise see( look in book)

Evaporative cooling

Exposing moist surfaces to air flow is the most effective way to cool a body - Swetaung - Panting - Homeotherms can withstand extreme heat if they have enough water - heat becomes a challenge only in desert environments= sweat= loss of water at a very fats rate

Ancestral character states are found only in the out-group. True or False

False

If a single measurement when repeated shows little variation, it has low precision. True or False

False

Phymata americana goes through complete metamorphosis. True or False

False

Two enzymes that have the same shape, size, and electrical charge will move at different rates through a cellulose gel. True or False

False

C4 pathway

Favour bright light and high temperatures - evolved in tropical grasses, maize, and sugar cane

finer-scale niche partitioning

Feeding in different zones of the coniferous trees - study on how so many insectivorous warblers by MacArthur - how some organisms coexist even if they seem to be filling the same functional niche - niche overlap on a scale from 0-1(sharing no resources - complete similarity

Rich soil

Fertile and well suited to plant growth. - generous concentrations of N,P,K. -Some necessary trace elements. - Low levels of harmful substances: toxic ions (Al, Pb) - intermediate water availability( depends on the texture of the soil particles. Xeric, hydrocarbon, mesic

Why pines predominate in south-eastern north America (review this)

Fire: - Hot places with dry sandy soil= susceptible to forest fires - many species of pine well adapted to forest fires - Leaf litter +fallen branches don't decay quick= flammable fuel fires - poor dry nutrients depleted soil shifts vegetation to pinelands

Kettlewell

First demonstration of the mechanism of natural selection in the wild and now featured in most biology textbooks and museums.

Flowers during dry season even though leaves are dropped:

Flowers are more visible- aid in dispersal of fruits by animal or wind In the tropical deciduous forest

Other places where chronic fires are critical

Forest-prairie border - grasslands burn frequently - they have herbaceous plants

Wright

Found that domestication in maize caused a reduction in variation at SNPs. Saw an important role for population structure and genetic drift in evolution.

Lenski

Founder of experimental evolution with E. coli.

the nature of plant communities

Frederic Clements - certain plant species occurred together more often than one would expect by chance - patterns of association - patterns of non-random co-occurrences -

equilibrium morph frequencies

Frequency-dependent mating and genetic drift in tristylous populations

Fast life histories

Fugitive annual weeds - High fecundity, low survival, short generation times, small but numerous seeds. good dispersal ability, poor competitive ability. - In a dichotomy, such plants and animals are called r-selected species or r-strategists (ex: weeds)

One branch of research to stem HSS argument

Graph-theory research into the topology & network properties of food webs In recent years it has become possible to quantify trophic levels by measuring ratios of stable isotopes in its tissue. -Don't always concur with observational data

Exponential model suggested

Great instability in population trajectories, species overpopulating or going extinct

Stochastic

Growth rate is a variable

predator who have are potential generalists

Have long-lived cycles in low-density communities

MSS proposition

Herbivores are not limited by their food supply but by their consumers -Only applies to entire trophic level not species populations

Secondary producers/ primary consumers d

Herbivorous animals that eat plants = second trophic level

The comparative method

How different organisms meet environmental challenges in different ways - syringes when we know something about how the species are related to each other Ex: close relatives Ex: convergent evolution

Size-number tradeoffs

If you make more seeds they have to be smaller

lessons from the rise and fall niche-based studies of communities

Importance of competition fades when species populations are routinely knocked down by other factors (predators, disease, bad weather, physical disturbances) - It assumes that communities must be equilibrial

1. Pest species

In agriculture or forestry or epidemiology - economic costs of population outbreaks, provide compelling rationale for research - Exact numbers don't matter; only if the pop. this year will be big/small

Succession is also characterized by plenty of inhibitive effects

In which earlier species change the environment in ways that retard the success of later species rather than hastening it -Both inhibitive and facilitating effects are coincidental consequences of particular properties of the species that natural selection favoured because of the positive effects on individual fitness, not because they produce certain kinds of successional change.

Introduction to population ecology: a taste of theory

Individual organisms -> populations - Population size (N): the number of individual organisms in a population

germ-plasm theory

Inheritance only takes place by means of germ cells (gametes)

Mesic soils

Intermediate water level soils

Reproduction survival tradeoffs

Investing resources in offspring means they can't be used in maintaining the body

The earth

Is a closed system in which energy propels atoms through characteristic biochemical cycles that depend on their elemental chemistry - elements are recycled into organisms

Distribution of species

It's geographic range ( the areas of the planet where the species may be founds - geographic ranges usually depicted as range maps

Perennials

Iteroparous plants are

Janzen-Connel hypothesis (pest pressure hypothesis)

Lack of winter in tropical areas means plants never get a break from attacks of herbivorous insects and other enemies (fungi). Attacks by specialists(can attack only one type of plant) - If a plant species becomes abundant, its natural enemies will prevent it from spreading Resul: -Only many can co-exist (no single plant species can become dominant) - seeds and seedlings experience higher mortality in the vicinity of their parent

organisms most capable of homeostasis

Large bodies complicated metabolisms - warm-blooded animals -birds, mamals

Humus

Leaf litter of the tropical rainforest: war6mth + humidity : fallen eaves quickly rot into humus

Theory why invasive species do so well in new environments

Left behind by their natural enemies: predators, parasites, diseases that controlled their populations

Solar equator

Line of latitude closest to the sun

Physiological ecology as a way of thinking about organisms

Living entities can be seen it different ways - Development: development of complex adult forms from unicellular zygotes - Physiology: metabolic processing of energy materials to fuel and supply all of that growth OR - organism=library info - w/detailed sets of genetic instruction written in DNA (it is heritable: connects organisms in a family tree of relatedness - Phylogenetic relationship (similarities and differences in our DNA) - Classification in terms of relatedness= taxonomy

Brown soils

Loamier: sand+clay+ organic matter= rich soils that are good for agriculture

Best soils

Loams-sand + clay+ plenty of organic matter

Baker's Law automatic selection

Long-distance dispersal favours selfing forms because a single individual can start a colony without mates or pollinators.

Tree species diversity of boreal forest

Low diversity - balsam fir + white spruce on uplands, tamarack + black spruce in wetlands - Deep shade prevents recruitment of seedlings from the canopy trees - Depending on light levels forest floor supports : herbaceous angiosperms., ferns, lichen, mosses

Auto pruning boreal forest

Lower branches are shed

Oceanic circulation

Massive packets of water produce circulation patterns(currents) in the oceans - Land and sea are not independent systems ( what happens in the ocean affects land masses) *Remember: biggest influence on what organisms live where is precipitation and temperature

wet seasons

May come from rain as intertropical convergence passes over, or from snowmelt that runs down watercourses from nearby nountain ranges.

2nd branch is study of trophic cascades

Measurable, important, indirect relationship b/w 2 trophic levels that are mediated through a third level ex: increase in 3rd level = increase in 1st level cause there is less 2nd level - Important in management of real world populations - Susceptible to experimental tests - Significant removal would cause top-down or bottom-up effects - Such tests are only practical in simple communities, and limited spatial extent -conducted in ponds or islets with low level diversity - demonstrate that trophic effects can cascade through systems in interesting ways ex: presence/absence of fish in ponds affect pollination of flowers on growing plants nearby - experiments in isolated patches banishes the possibility for metapopulation structure and interpatch migration

Soil composition

Minerals + organic matter N,P,K: beneficial Al,Pb : bad

As time goes by

Modeling population changes through time.

desertification: -

Moderately productive prairie converted to less productive desert; worrisome process -Most important factor: Grazing by domesticated livestock, especially goats - climate warming - fires play no role in deserts bc, plants aren't productive enough to produce critical amounts of fuel needed to sustain a burn

Pika

Most characteristic mammal of Northern-Hemispher alpine tundra.

Orogenic precipitation:

Mountain- generated precipitation

For a closed population with no immigration/emigration: N_t+1=N_t+B-D

N_t+1= population size one year in the future N_t= population size now B= births D= deaths - if population not closed, treat immigration as births and emigration as deaths - But better to express birth and deaths as per-capita rates - ex: per capita death rate is 0.5 per individual if 1/2 population is expected to live and 1/2 to die - Can calculate magnitude of population change by multiplying the rate times the # of individuals N_t+1=N_t + N_t (per capita rate)- N_t (per capita death rate

Differential equation for exponential growth

N_t= N_0E^rt - e= constant, base of ln - t appears as exponent again= population explodes or goes extinct really fast

transition zone

Narrow and obvious - In artic :location of treelines is where permafrost occurs (lower layers of soil stay frozen all year - waterlogged soil during short growing season

Non adaptive trait

Neutral

Primary succession

Newly created habitat that has not supported

H.J. Muller

Nobel-prize winner; studied the effects of radiation on mutation rates

Do real predators and prey display long-running lagged cycles

Not in lagged cycles due to no persistence from the prey. - irl persistence from both ways is common from both ways - physical structure give hiding places/refuges for the prey - predator population declines without having wipes away all the prey Natural populations offer multiple prey species that predators can take - predators like to switch to the more abundant prey which allows prey populations to recover Predation can prevent inferior competitors from being outcompeted by superiors

geometric growth model

Nt+1=λNt Nt=Noλ^t

Temperate rain forest

Occurs in few small areas where cool-cold winters and continual rain - espectacular forests with moss covered tress

Maritime vs, continental climates

Oceans influence nearby land masses by providing thermal inertia - Ocean- influenced maritime climates buffered against temperature extremes (spring arrives slowly, but summer lingers)

Clements viewed succession:

Of a community as analogous to the developmental stages of an organism - Plant communities developed for a while, reached a climax (formation that no longer underwent change) - Unstable stages called "seral" stages - stages are largely predictable

Schlerophylly is the characteristic

Of having leaves that are small, thick, tough and leathery and almost always evergreen - often contain essential oils (pungent smelling+flammable) - particular combo of heat + water stress

The sclerophylly puzzel

One characteristic can serve multiple different functions in different habitats

Why are there so many different species of living things?

Organisms adapt to their environments through evolutionary ecology

Physico-chemical reasons temperature+ water

Organisms in danger of overheating, overcooling etc..: 1. Environments contain broader range of physical conditions than narrower ranges of tolerance that characterize organisms 2. Things tend to equilibrate 3. Environment much larger than organisms, so equilibration is asymmetrical * organisms are essentially vulnerable, environments are essentially merciless To stay alive organisms must be able to combat tendency to match their environment - Must jeep internal states constant: homeostasis = thermoregulation + osmoregulation

guild levels

Organisms share a guild if they have similar functional niches

Leaves

Organs used to harvest energy from environment + conduct Gad exchange. When they fall these

Interactions

Overly hostile encounters (predation + competition),mutualism

Dark soils

Oxidized organic components

Does predation actually counteract competitive exclusion in nature

Paine= experiment of starfishes - removal of starfish-> the surfaces became dominated by a single species of mussel = they created a monoculture unless something restrained them

Disturbance: Towards a more inclusive view

Particular disturbance regime that characterizes a habitat - Notion of climax in not applicable in a lot of situations (constant disturbances in some environment doesn't let succession get past its earlier stages) - fire is recognized as another component of the environment (species that live is such habitats develop clear adaptations to it) -

Solar light transfers heat to the earth

Photons of light hit surfaces other than air (solid+dark) are absorbed and reradiated at longer, infrared (IR) wavelengths IR radiation is absorbed by the atmosphere - Solar input hats the air at the bottom of the atmosphere, heating is strongest near the equator

The coevolutionary arms race

Plant defences make life hard for herbivores yet herbivores are wide spread - herbivory came first, diversification came after - Evolutionary relationships b/w plants and insects that eat them = evidence of coevolution that leads to specialization and speciation - speciation is augmented by antagonistic interactions - parallel adaptive radiation (insects vs plant chemicals) = generating astonishing diversity of insects & flowering plants - herbivorous lineages typically produce more species This pattern does not appear in mammals -Insects must handle 1 plants chemicals - mammals can move through their habitat and make choices - They can handle toxic chemicals by selecting mixed diet in which they can avoid poisonous & take milder toxins in low doses

Boreal forest biomes soil

Poor soils: - conifer needles = acidic leaf litter ( interacts w/rain +snow to produce leached sandy soils with little nutrients and organic matter)

Deterministic model

Population growth rate is constant - unrealistic; nothin is constant irl

Range of tolerance abiotic factor

Portion of an ecological gradient that a species is restricted if the factor that varies along the gradient is a limiting factor - Bell-shaped curves - graphed as curves -Peak= optimal environments/best-suited for the organism to throve - Increasing distances from optimum = environment increasingly stressful * unable to grow well enough to reproduce * unable to grow at all * become unable to live (death zones)

Other ways to prevent competitive exclusion

Predators, parasites and diseases are specially effective mechanisms for keeping populations below carrying capacity by counteracting competitive exclusion - natural enemies tend to act in density- dependent manner - abiotic "disturbance events" can affect community

Why are temperature and water so important

Processes that permit life are chemical reactions that occur in aqueous solution reaction rates depend strongly on temperature and concentrations of reactants: Temperature - catalyzed by enzymes - enzymes are proteins - At high temperatures proteins denature - Natural selection can produce heat-resistant enzymes but resistance is limited - Because of the fundamental temperature dependence of chemical reactions all forms of life are limited by extremes of cold and heat Water: affects concentrations of chemical reactions - cells and tissue depend on membranes - Proper function depends on osmotic balance - Too dry= concentrations of dissolved salts increase (rxns slowed, changed, eventually stop) - oo much water in cells= reactants get diluted and fail to combine as needed

Stable age distribution

Proportion of population in each class stabilizes

Reproductive value

R.A Fisher = reproductive value (v_x) another aspect of life history that is a function of survivorship and fecundity schedules *Expected # of daughters to be produced by a female of age x, now and for the rest of her lifetime * is a statement of the current value of an organism for future fitness * only looks forward in time * any offspring produced before age x are irrelevant to v_x - can calculate v_x by rescaling the I_x values as if the organisms were starting life at the age for which you are calculating reproductive value - tricky concept: graph of v_x vs x = humped shape with max b/w youth and old age - reproductive value declines later in life - a newborn has to get through the pre-reproductive, resource-acquisition phase of her life before reproducing & has risk of dying during that period

Inorganic/mineral components

Range from particles (sand) to tiny ones (clay). Can also have wind-blown dust (losse) or water-deposited sediments (alluvium). Particles hold ions that are either dissolved or precipitated out

Phylogenetic trees

Reconstructing evolutionary relationships from DNA sequences enhances the comparative method

Maladaptive trait

Reduces the organisms fitness - are prominent in changing environments - can be maintained by tradeoffs and constraints(reduce fitness)

Adiabatic lapse rate:

Relationship of temperature drop to altitude gain - strongly affected by humidity -for 1km rise, air temp drops to 5˚C w/ humidity, 10˚C with dry air

Principle allocation

Resources invested in one function are unavailable to invest in other functions

Key tradeoffs

Responses to environmental challenges are subject to constraints and tradeoffs (have to do with allocation of limited resources) * ex: production of offspring is affected by size-number tradeoff

Monocarpic

Semelparous plants (making fruits once)

Chronosequence

Series of replicable habitats of various ages

Orogenic precipitation and rain shadows

Sharp differences in rainfall arise when topography interacts w/prevailing winds Ex: West coast of North America (air from the Pacific rises up mountains, cools and condenses= causes precipitation as it rises ) - Dry air descends eastern slopes - warms up from compression and friction (now dey and desiccating ) - Permanent rivers support narrow bands of richer taller vegetation along banks *riparian vegetation * gallery forest (in the tropics) -vegetation of slopes with different exposure to the sun= different vegetation

Deciduous

Shedding leafs annually

Desert annuals

Short-lived plants - wait out one more dry season as dormant seeds -winter wet enough-> seeds germinate and plants rush to grow, flower and set new seeds - water-soluble compounds in their seed coats - prevents them from germination unless exposed to - - enough water to dissolve away inhibitor - mechanism coordinates germination with especially wet years Concentrated blooming of annuals in early spring - compare: desert annual strategy with spring ephemeral strategy in TDFB - increasing in the area ->desertification: moderately productive prairie converted to less productive desert; worrisome process) -

Spring ephemerals:

Small perennial plants of the forest floor - understory herbs found only in TDFB - emerge and produce flowers as soon as snow melts, before canopy trees leafed out. - harvest light for a brief period before habitat becomes too shady - when tree canopy closes in they stop flowering, shed their leaves, produce seeds, disappear - they are dormant underground roots/bulbs for the rest of the year "carpet of flowers"

parent material

Soil is formed by the action of living organisms and geophysical processes on some mineral substrate 'called parent material' - often bedrock, sometimes sand deposits -greatly altered by biological processes and chemical actions - has a mineral component by and I gaming component

tangled bank vs red queen

Spatially heterogeneous environments. Temporally heterogeneous environments

Logistic model suggest:

Species settling into their carrying capacity, staying in a permanent equilibrium *there are some regulatory processes at work (especially crowding effects) * but scientist are moving away from an equilibrial point of view -more modern research suggests this model is a poor model of reality *scientists researched cultures of protozoa and yeast, found that once population leveled off, they would experience crowding effects and undergo population crashes * It is quite hard to maintain the population at a steady value look at graphs on notes

Ranges

Stable parts of species biology

Alpine tundra

Starts at 3500m elevation at our latitude - no permafrost or saturated soils - trees can't grow bc physical stress (especially ice pellets carried by strong winds) - near treeline trees pruned doesn't to shrub size by wind - very dangerous lethal climate - mountain goats and sheep- move down t shelter sites at lower elevations - small animals burrow under the snow or in underground burrows - rodents, winter-active voles, pocket gophers +hibernators (are also found in subalpine meadows, would be good prey for reptiles if it weren't so cold)

Plant defences are highly diverse

Structural and chemical

P+R Grant

Study of natural selection in Galapagos finches

Fires and boreal forests

Subject to large-scale disturbances, - deadwood+ slow decaying matter = deep layer of fuel floor that maybe flammable by terpenoid resins that give the trees their smell (hot summers + dry fuel + lightning = massive fire + more buildup of litter = hotter fire) - croen fire= whole trees consumed by tremendous heat

Seasonality

Temperate zones: depends on temperature differences Tropical: depends on precipitation -ITCZ hardly moves in few places = uniform rainy climate all year - ITCZ swings over a range of latitude in other places = 1 or 2 rainy seasons separated by dry seasons

Clements thought (example above)

That all succession worked this way - this would only make sense if community were an organism - but its not and natural selection doesn't act to produce altruistic chivalry towards other species

Location of boreal forest biome

The boreal forest biome lies north of TDFB, across Alaska, Canada, northern Europe, Siberia - Not in the south due to little landmass at same latitude

Animals of the deciduous forest

The canopy is hard to navigate - small invertebrate plant eaters= small vertebrate predators (mice, moles, shrews, birds, - lots of insectivorous birds, most migratory - fleshy fruits only available for brief periods of summer-> ripen when birds migrate - Has true hibernators (squirrels, groundhogs)-> slowdown of metabolism & bears, raccoons -> sleep through winter and eat very little -> build up of fat reserves in the autumn -Foxes, deer, rabbits, mice, and others remain active all year- generalized diets - Winter is the season of stress, when carrying capacity is determined (food scarce, shorter days-less time for diurnal species to forage)

genetic polymorphism

The occurrence of two or more discrete forms of a species in the same locality in such proportions that the rarest cannot be maintained by mutation alone.

Ecological niche Official definition:

The particular microhabitats that a particular animal species frequentes+ characteristic behaviours that the organism employed in exploiting its environment

Fisher's fundamental theorem of natural selection

The rate of increase in fitness of a population at any time is equal to its genetic variance in fitness at that time

Ferrell or mid-latitude cells

The second pair of conveyor belts initiated by flows that move toward the poles - not as strong or consistent as Hadley cells (driven by the same process) - As air moves across surface towards poles it picks up moisture (creates pair of raini+snowy low-pressure zones around 60˚N&S -rising air shoed towards N&S by continuous upward flow from beneath -High-level flow towards equator close Ferrel loops - The flows toward the pols set up the 3rd pair of circulation loops: polar cells

trophic interactions

The struggle of the food web (who eats who)

Science of ecology

The study of factors determining the distribution. And abundance of organisms

Thomson experiment

Theory: plant species experience the most niche overlap should have received the worst pollination service - IRL: no correlation b/w niche overlaps and pollination success - Conclusion: overlaps did not measure competition Real communities are non-equilibrial (populations are influenced by factors other than competitions)

Why is the world green

There is a lot of plant material not consumed by herbivores - Herbivores are not limited by food supply - not all unconsumed leaves are edible In recent years it has become possible to quantify trophic levels by measuring ratios of stable isotopes in its tissue. -Don't always concur with observational data

Fugitive species

They keep having to discover new bare patches

Air is considered transparent

Thickness of atmosphere doesn't really effect amount of light reaching earth's surface - most of the energy reaching the earth from the sun is in the spectral range of light, and those wavelengths pass through air without giving up much of their energy to the air molecules

Earth's atmosphere

Thin layer of gasses pressed against earth by gravity

- as air rises, creates partial vacuum beneath it

This suction causes surface air to be drawn towards the solar equator, moving south and north - As air rises, expands, then cools then drops

Diversification of life

Through adaptive evolution driven by natural selection imposed by the environment

Life-history traits

Timing of life events and amounts of resources that individuals invest in such functions ( ex:maturation, reproduction) look in book for it

Epiphylls

Tiny plants that grow on leaves of larger plants (algae, mosses, lichens) - Can completely cover host leaf = shutting off photosynthesis.

Pleiotropy

Trait that has more than one function Ex: an elephants ear ( hearing and body temperature regulation)

ecotone

Transition zone between true vegetation types

Natural selection process

Trial and error. Evolution does not produce perfection - selects for new variants that perform a little better than the previous model

Latitudinal lines at 23.5˚S

Tropic of Capricorn

Latitudinal lines at 23.5˚N

Tropic of cancer

A 'character' can be morphological, developmental, behavioural, or molecular. True or False

True

An ancestral trait is more or less unmodified and is shared among various species. True or False

True

Experiments are conducted to test a hypothesis. True or False

True

The standard error of the mean is a measure of how reliable the sample mean is as an approximation to the population mean True or False

True

Principle of competitive exclusion

Two species that complete for the same resources cannot coexist for long

Louis Agassiz

United States naturalist (born in Switzerland) who studied fossil fish recognized geological evidence that ice ages had occurred in North America (1807-1873)

when considering how two-species population might compete

Use logistic model - Lotka and volterra developed models for the competition bw 2 species and predator-prey interactions

Biomes

Very different sets of characteristic organisms in place with different climate. Defined by their possession of characteristics collections of resident species - develop different types of soul which limits what plant species can thrive there - species range limits correspond to boundaries between different biomes

Xeric soil

Very dry soils. Organisms Require special adaptations to grow.

Prevailing westerlies

W-> winds

When rainfall is not heavy

Water penetrate soil to moderate depths, is pulled back up by plant roots. - what're is retired to the atmosphere by evaporation - ions stay in the rooting zone of plants

hydric soil

Water saturated soils. Organisms require special adaptations to grow.

Polar cells

Weakest and most diffused of the 3 cells

Atmospheric pressure

Weigh of a column of air that compresses the air at the bottom

Leaching

When heavy rainfall carries dissolved nutrients below the reach of plant roots- resulting in nutrient poor soil.

Hummus

When organic matter becomes so decomposed that it's spice is no longer recognizable

Why the loss of leaves?

Winter inflicts damage on broader leaves, they weigh down on the branches. During summer leaves are prone to over-heating, loss of water.

Lianas

Woody vines rooted in the ground but climb up host trees to reach canopy (cheap way for a plant to get to sunlight wéo building own trunk) depends on wet tropical conditions

Intertropical convergence zone (ITCZ)

Zone of rising heated air - "intertropical" because solar equator moves bw 2 tropic lines over the year - The two circulation loops: Hedley cells

gene flow

a certain gene goes from one population to another

recombination

a combining of genes or characters different from what they were in the parents

pseudogene

a gene that is no longer functional

common ancestry

a group of organisms share common descent if they have a common ancestor

Alfred Russel Wallace

a naturalist who had the same thoughts on evolutionary change as Darwin/around same time

sexual selection

a selection that increases an individual's chance of getting a mate

population bottlenecks

a single sharp reduction in numbers causing a loss of diversity

What about real organisms

abiotic conditions are important in determining the outcome of biotic interactions between species - the more efficient species were able to increase its population at the expense of the less efficient competitor

mutations

accidental and random changes in sequence of dna that occur as errors during cell division

ferrell cells

air converges at low altiltudes to ascend along boundaries between polar air and subtropical air between 60-70 degrees north and south, move in opposite direction of other two cells

orogenic precipitation

air forced up mountainside undergoes cooling, precipitates on upper windward sides

Clements predicted:

all forest in a particular climatic region will reach climax configuration - He dismissed obvious variation among different real forest stands as unimportant differences in developmental stages (all fated to converge to the same composition in time) - Believed principal forces driving successional turnover were autogenic processes

An ecological community

all of the organisms/biotic entities in some spatially defined locality can be taxonomically-defined or functionally-defined

assumptions

all patches have identical properties & colonization varies with proportion of patches occupied e- probability of extinction c= colonization p= equilibrium proportion of patches occupied p- 1- e/c

different forms of a gene

allele

polymorphic neutral genetic variation

allow us to find parents and track alleles from other populations

variations of proteins

allozymes

Exponential growth model

also describes density-independent growth with fixed birth + survival rates - Use a differential equation - births and deaths occur continuously: population growth trajectories are smooth functions rather than step functions - slope of curve= speed of population increase at that point (dN/dt=rN)

Potential evapotranspiration

amount of water that could be lost to the atmosphere if that amount of water were available in the system - Measure of the drying-up power

ectothermy

animal relies on external heat sources to maintain body temperatures

poikilothermy

animal's internal temperature can vary a lot

Matrix

areas outside the species range of tolerance (death zones)n

sensory- bias models

assume that the evolution of sexual dimorphisms are driven by pre existing biases in a female's nervous system

reasons for sexual dimorphic traits

attracting mate, winning competition, marking territories, making sure female doesn't get fertilized by another male

heterozygosity (H)

average frequency of heterozygous individuals per gene locus

lottery model

benefits of genetic variation in variable environments (reproduction = variation → ability to adapt in different environments)

nested hierarchy

big groups of species who share few traits that split into smaller groups that share more and more traits

theropods

bipedal carnivores

Net reproductive rate (¥):

birth rate - death rate

transcending biomes

broad temp tolerance, broad habitat range

evolution

change in the proportion of alleles in a population/species undergo genetic change over time

autopolyploidy

chromosome duplication in a single species

phenetics

classification of studies based on overall resemblance

most important (and broadest) range limiting factor

climate

Charles Elton

coined "food web," ecology in terms of of physical factors and animal behaviours

Metapopulation

collection of numerous smaller subpopulations spread across space - concept rooted in idea that a region will contain numerous discrete patches of habitat - a patch: potentially suitable home for a subpopulation of a species under study - suitable patches spread through a matrix of unsuitable habitat - members of the species can disperse across unsuitable habitat to reach suitable patches - migration and colonization need to be infrequent for metapopulations to have interesting properties - the isolation and disconnection let us treat subpopulation as quasi-independent entities -empty patches can be recolonized by individuals from occupied patches proportion of patches occupied depends on balance b/w extinction & colonization rates

founder event

colonization by few individuals that start new population with limited diversity within source population

deterministic

constant growth rate

example of a biotic effect on species distribution

coyotes are never abundant in areas w large pop. of wolves - wolves are more powerful and will hunt the coyotes

After fire or windstorm Boreal forest

creation of large clearing, a new crop of tree seedlings will get started all at once - New recruits will develop into even-aged forests w/special properties - Competition for light = all trees stunted by crowding = poor conditions for timber growth - Even-aged stands suffer if they get old together (all trees become vulnerable to insect herbivore at same age -The mountain pine bark beetle is destroying boreal coniferous forests

William Paley

creationist

most common is the logistic model:

dN/dt = rN ((K-N)/K) dN/dt = rN (1-(N/K)) based on the exponential growth model - added a new term that acts to "put the brakes on" dN/dt while leaving r as a constant *parameter k: carrying capacity of the environment * the number of individuals that the local environment can support indefinitely as a steady state - the resources needed for growth and reproduction are available -to the organisms in our population at a constant rate - as N gets close to K: resources are being used up, growth slows to a crawl - population size N approaches K asymptotically

Exponential model for model for population growth (differential equation)

dN/dt =rN r= measure of net growth rate analogous to ¥ * intrinsict rate of natural increase/Malthusian parameter/ litter 'r' r= instantaneous birth rate (b) - instantaneous death rate (d) r=0: population steady r> 0: population increases r<0: population declines - there are numerous solutions to this equation

exponential growth model

dN/dt=rN Nt=Noe^rt

logistic growth model

dN/dt=rN(1-N/K) K=carrying capacity

Lotka-Volterra Model

dN1/dt = r1N1 [1 - (N1 + a12)/K1] dN2/dt = r2N2 [1 - (N2 + a21)/K2]

Levin's model of patch occupancy

dP/dt=cP(1-P)-eP c=colonization P=fraction of patches occupied e=extinction

delayed maturation

delay of maturation of offspring in front of parents

population logistics use

density- dependent equations to portray mathematically simple models of regulations

evolutionary history

determines evolutionary relationships in terms of common ancestry

evolutionary mechanisms

determining processes responsible for evolutionary change

G.E. Hutchinson

developed a niche concept that expanded to both function (job) and habitat (place) using geometric analogy (n-dimensional hyper volume)

variation

differences in physical traits of an individual from the group to which it belongs

Law of Battle

direct competition between male to leave their genes to the next generation

embryonic arches

direct development of gills in fish

remnants

do not seem to have any function

inhibitive effects

earlier species change the environment in ways that retard the success of later species rather than hastening it

multiregional theory

early man developed from neanderthals and homo erectus in different regions

Charles Lyell

earth was old, current geology had clues to natural living history

aij

effect on i by j

red bank hypothesis

environment and species co-evolve to create constant probability of extinction

Allogenic

environmental changes by external forces (flooding, soil erosion) Principal in plant succession: 1. Those involved with soil development (important for primary) 2. Competition for light (imp.for secondary)

microevolution

evolutionary change within a species or small group of organisms, especially over a short period

Secondary succession

existing plant community is erased by a disturbance; after the disturbance plants disrupted but soil intact

retrodiction

facts and data that aren't predicted by a theory but rather only make sense because of the theory

disruptive selection

favours both extremes

directional selection

favours one extreme

vestigial trait

feature of species that was an adaption in ancestors but has either lost its usefulness completely or been co-opted for new uses

atavism

features that express remnants of ancestral features

λ

finite rate of increase

¥

finite rate of increase/ geometric rate of increase= multiplication factor by which a population changes from one interval to the next. = 1 -> population size stays steady >1 -> population size increase < -> population size decreases - starting population size is N_0 - population grows by a factor of ¥ each year = N_t = N_0¥^t

tangled bank hypothesis

fitness and development of sexual reproduction having to do with changing/variable physical environment

Grassland-forest border

forest fires try to push this border into areas where local climate would favor forest in absence of fires

Cushion plants

form dense hemispherical dome of leaves allows wind to flow over plant

endemic species

found nowhere else in the world

August Weismann

founded neo-Darwinism by rejecting Lamarckian elements of Darwin's original theory, germ-plasm theory

reproductively isolated

gene pool doesn't intermingle

Endotherms

generate their own heat

theory of blending

genes from both parents mix together irreversibly

vestigial genes

genes that make traits that are no longer useful are inactivated in DNA

dead genes

genes that were once useful but are no longer intact/expressed

genotype

genetic constitution of an organism

Ramets

genetically identical plants

population

group of individuals of the same species that live in the same area at the same time

Biennials

grow vegetatively for one year, flower, die in their second year - In stressful times it takes more years to accumulate resources to flower

causes of extinction

habitat destruction, overexploitation, invasive species

å competition coefficient

has two subscripts: 1. species 1 out competes 2 2. the opposite so å12vs å21

Flag trees:

have branchesgrowing on leeward side of tundra where buds can escape wind damage

evaporation ___ from warm bodies of water

high

In wetter areas boreal forest

high water tables= shallow roots +taller trees = easly overthrown by windstorms

Bergmann's rule

homeotherms tend to be larger at higher latitudes

Allen's Rule

homeotherms tend to have smaller appendages at colder/higher latitudes

homeothermy vs poikilothermy

homeothermy= maintains body temperature poikilothermy = Connot regulate body

Hunting in TDFB

hunting has eliminated deer, elk, moose & their predators = wolves, mountain lions, lynxes This is bad because plants are becoming rare because of deer browsing

adaptive radiation

identified by recent common ancestry, phenotype-environment correlation, trait utility, and rapid speciation

principle of superposition

in a series of stratified sedimentary rocks the lowest stratum is the oldest

Gleason's proposal

individualistic, continuum, open-community hypothesis

dispersal

individuals move away from area of birth

mechanism of natural selection

individuals within a species different genetically which affects ability to survive and reproduce, so "good" genes lead to increased reproduction rates and over time population will be more suited to their environment

Jean-Baptiste Lamarck

inheritance of acquired characteristics

driest deserts

inland of cold water upwellings, cold water = dry air

mesic

intermediate between dry and wet

species diversity

interspecific variation or species diversity (studied by ecologists)

r

intrinsic rate of increase, r=lnλ, r=lnRo/T

population-wide synchronization is not restricted

is not restricted to semelparous plants - nut bearing trees, especially oaks, produce heavy crops (mast crops) every 4 years (are regular iteroparous perennials) - predator satiation is probably a factor in masting by oaks "big bang" synchronization *exempt salmon * a spawning salmon transfers so much of its tissues into gametes it dies in the process

phytosociology

is the branch of science which deals with plant communities, their composition and development, and the relationships between the species within them: Trees, shrubs and herbs of a forest must be playing particular roles (doctors, student, laborer etc...)

temperature climate patchiness

land changes temp more readily than water, maritime climates are moderate, continental are extreme, oceans provide thermal inertia

source patch

large, suitable, maintains a growing subpopulation, is a net exporter of dispersing colonists

macroevolution

large-scale evolutionary changes that take place over long periods of time

hadley cells

largest, from equation to 30-40 degrees north and south, blow towards and ascend near equator, heated air rises and cools, governed by adiabatic lapse 5ate, as cools vapor condenses and falls as rain near equator then warms as it falls (adiabatic process reverisible)

temperature gradient function of

latitude

laterization

leached of good nutrients, and red and clay rich.

folivory

leaf eating

lineages

lines of descent

Monocarpic perennials

live longer than 2 years before flowering and dying

Annuals

live one season

evaporation ___ from cold bodies of water

low

sink patch

low quality, incapable, maintains a growing subpopulation except through immigration, is a net importer of dispersers, if dispersal is cutoff, subpopulation in sink patch would go extinct

outbreeding

mates less closely related than random

inbreeding

mates more closely related than random

limiting similarity

maximum amount of niche overlap that would allow species to coexist

Positive social interactions

members of populations facilitated each other's survival and reproduction, instead of harming each other through intraspecific competition - negative effects predominate at high densities - positive effects prevail at low N - Mate finding - Animals often congregate in groups that conger mutual protection against predators *warning alarm calls, dense schooling behaviors that confuse predators/deflect attacks, gaging up - animals can get hints as to where to find food from conspecifics behavior ex: geese fly in V formation to fly with less energetic costs - animals work together to provide protection against physical stresses - all of these are called "allele effects" - these are especially important in conservation ecology, bc their problems are concerned with rare species - if effects strong enough can be a lower threshold of numbers, below which population declines - can modify logistic by adding second braking term: dN/dt = rN (N/A -1) (1-N/K) A= allele threshold K= carrying capacity - if population N size dips below A, dN/dt goes negative and population declines to extinction - irl, very hard to determine value of A for an endangered population

post-mating competition

methods that males use to prevent other males from fertilizing a female and stealing his paternity and/or methods males use to steal paternity from other males

Stochastic model

model growth rate as a variable (as a probability distribution with a specified mean variance) - would graph thousands of population growth rates (iterations) - Examine the statistical properties of a collection of trajectories *average population size, max pop size, any extinction

molecular clock

model that uses comparisons of DNA sequences to estimate phylogeny and rate of evolutionary change

sexual reproduction vs. asexual reproduction

more variation, females have limited # of eggs whereas males have unlimited # of sperm cells

migration

movement of individuals from one population to another

classical school

mutation selection balance, lab mutants, high homozygosity, low polymorphism, wild type is best genotype; purifying selection reduces diversity

positive selection (adaptation)

mutations that increase fitness will become fixed in a population

purifying selection

mutations that reduce fitness are removed by natural selection

Basic model for geometric growth

n_t+1 = N_t¥

biological classification

name is key to literature and has predictive power, enables interpretation of origins and evolutionary history

favoring diversity

natural selection can act to maintain diversity over the long term

balance school

natural selection favors diversity, natural populations, low homozygosity, high polymorphism, no best or ideal genotype; balancing selection favours diversity

allopolyploid speciation

occurs when two species hybridize and give rise to a new species

rain shadows

on leeward side

continental islands

once connected to continent but separated by moving continental plates or rising sea levels

polyandrous

one female and many male

biogenetic law

ontogeny recapitulates phylogeny

phenotype

organism as observed

Clements proposal

organismal, hollistic, communitu-unit or closed-community hypothesis

Detritivores/ decomposers

organisms that extract their carbon from dead organisms

Autotrophs/primary producers

photosynthesizing green plants that make their own food from CO2 first trophic level

epiphytes

plants that grow on other plants but do not obtain nutrients from their hosts

Aric tundra in summer

ponds, lakes, bogs, low-growing plants that can take water-tolerated soils (very hydric soils)

deterministic

predictable

ecosystem properties

primary productivity (ex: how much plant growth occurs per area per time), biochemical variables (like nitrogen uptake, gas exchange)

parthenogenesis

process where female produces eggs that develop without fertilisation

heredity

progeny resemble parents more than unrelated individuals

polymorphism (P)

proportion of gene loci that are polymorphic (genetically variable)

Rain shadow

rain-starved regions that result in xeric(very dry soils) vegetation

genetic drift

random change in the frequency of genes over time

stochastic

random, unpredictable

core ideas in physiological ecology

ranges of tolerance, organisms are complex chemical rxns, rxns occur best at optimum temp and osmotic conditions, homeostasis mechanisms have evolved to challenge hostile environments

The logistic model of density dependence

real populations do not behave according to exponential or geometric equations - we do see some extinctions but rarely population explosions* when they occur they are stopped by crowding - there's a tendency in nature to regulate the extremes of population growth -

inbreeding depression

reduced fitness in inbred offspring in comparison with outcrossed offspring

Regulation of population size

regulated at a constant 'carrying capacity' set by the environment

quantitative inheritance

relation between gene number and phenotypic variability

fitness

relative genetic contribution of individuals to next generation as a result of differences in viability and fertility

Iteroparity

reproduce numerous times = the norm

Semelparity

reproduce once in their lifetime = special circumstances

abiotic factors

resources, conditions, gradients

oceanic islands

rise from the ocean floor

branchial arches

series of 5-7 pouches separated by grooves

T.H. Morgan

showed that genes are located on chromosomes

histograms

shows distribution of continuous data (ex. height)

Genet

single genetic individual

SLOSS

single large vs single small, which reserves were a superior means of conserving biodiversity in a fragmented habitat

microevolutionary change

small changes in one or a few features of a species

epiphylls

small plants that grow on larger plants

For the outcomes no memorization

small å = coexistence large å = produce extinctions of inferior competitors

polar cells

smallest and weakest, between 60 and 70 degrees north and south to the poles, air sinks over highest latitudes and flows out towards lower latitudes at surface

why organisms are picky with mates

some "show-off" traits are signs of health

selection

some forms more successful at surviving and breeding than others in a given environment

selective advantage

some individuals are better adapted to the environment and thus have higher fitness, characteristic of organism that permits it to produce more than the average # of offspring

Ranges:

special characteristics of a species - they can shift Ex: cardinal's habitat moved northward into canada over past decades

geographic range limits

special habitats, other organisms, transcend biomes

Jansen-Connell Hypothesis

specialist natural enemies, such as herbivores and pathogens, maintain diversity in plant communities by reducing survival rates of conspecific seeds and seedlings located close to reproductive adults or in areas of high conspecific density

convergent evolution

species that live in similar habitats experience similar selection pressures

"leslie matrix"

square matrix in which top row holds bx values, subdiagnol hold survival data (s_x), where s_x=I_x+1/I_x - post multiplying this matrix by vector of current age structure at time t=age structure at next time interval t+1 - This process can be repeated indefinitely, projecting future changes in population size and age structure

adaptation

state or process

theory

statement of what is held to be general laws, principles, or causes

systematics

study of biodiversity and evolutionary relationships

embryology

study of embryos and their development

biogeography

study of the distribution of organisms around the world

community assembly rules

successful colonizers would be the ones whose niches were different from those already established = can understand + predict species dynamics of communities

Out of Africa Theory

supported by fossils, homo sapiens originated there and traveling out (killing/out-competing neanderthals and homo erectus in the process)

gradualism

takes many generations for a species to produce substantial evolutionary change

Temperate deciduous forest biome (TDFB) typical vegetation

tall trees which thin broad, fragile leaves - last for a single summer then actively shed - oak, Naples, hickories, ashes, beeches, etc... - Eastern half of North America, Europe, China and Japan

podsolization

tan, sandy, and acidic

the fossil record

tangible historical evidence for evolution

non-monophyletic

taxon whose members are derived from two or more ancestral forms not common to all members

most important factors for aquatic plants

temp, disturbance, salinity, nutrients

endothermy

temperature is kept constant by internal physiological processes

"Red Queen Hypothesis"

temporally heterogeneous environments (environment change)

plasticity

the ability of a genotype to modify its phenotype in response to changes in the environment

genome

the entire organism's DNA including both genes and non-coding regions

speciation

the formation of new and distinct species in the course of evolution

continental drift

the gradual movement of the continents across the earth's surface through geological time

biodiversity

the variety of life in the world or in a particular habitat or ecosystem (# and kind of organism in a given area)

tree down scenario

theropods lived at least partly in trees

Evapotranspiration

total amount of water that is transpired from plant leaves

sexual dimorphism

traits that differ between males and females (apart from sexual organs) that help with sexual selection:

bar graph

used for discrete quantitative variables that are similar but not related (ex. traits in trees)

molecular taxonomy

uses similarities and differences in gene sequences to classify organisms

xeric

very dry soils

what material do plants compete for in desert biome?

water (not light)

alluvium

water deposited sediment in soil

Darwin

went to Edinburgh for med school but dropped out, set out to be a minister and completed undergrad at Cambridge, influenced by botanist John S Henlow

divergent selection

were once the same species, distanced by geographic barrier and evolved with new environments (sister species)

roaring forties

westerly winds in southern hemisphere, between latitudes of 40 and 50 degrees

twofold cost of sex

where "asexual" gene would produce twice as many copies of itself as did the original "sexual gene"

stabilizing selection

where and intermediate form of an organism is prefered over the extreme forms in selection

example of habitations in the coniferous boreal forest

white spruce vs black spruce

loess

wind-formed deposit made of fine particles of clay and silt

lianas

woody vines