ECCB 205 Exam 2
Ectotherms vs. Endotherms
"cold-blooded" vs. "warm-blooded"
What Kind of Interaction is Competition?
(-,-)
how to solve for per capita growth rate
(dN/dt)/ N
In which model is per capita growth rate the same as r?
(dN/dt)/ N = rN / N
Natural Climate Forcings
- Volcanic activity (declines in temperature) - Changes in solar output - changes in earth's orbit
cost of sexual reproduction
- energy and resources to sexual organs - mating is energetically costly - elevate risk of herbivory, predation, and parasitism - reduced fitness
The Western gray squirrel population grows exponentially, and then begins to be restricted by availability of resources. Assuming an intrinsic growth rate of 1.8, and a carrying capacity of 12,000, what is the per capita growth rate when the population is at 14,000 individuals?
-0.3
Imagine that the average July temperature over the last 100 years of a beautiful tropical island is 40°C. Suppose further that this past July, the average temperature was 38°C. What was the temperature anomaly for this past July?
-2C
The average low temperature of February in place X between 1981-2010 was 47°F. The average low temperature of February 2019 in place X was 42°F . What is the the anomaly for the average low temperature of February 2019 in place X? Give a numeric answer. The units are °F
-5
Endoparasite advantages
-ease of feeding -protected from external environment -safer from natural enemies -but exposed to immune system and harder to transfer
Ectoparasites advantages
-transfer more easily -don't have to fight against host immune system -but are more exposed to environmental factors
The population density of a particular insect species was determined to be 21,000 adults per hectare in the summer of 1996, and 15,000 adults per hectare in the summer of 1997. Based on these population estimates, what is your estimate of λ, the annual rate of geometric growth?
0.7
Types of mutualisms according to type of benefit
1 Mutualisms can aid in defense against enemies. 2 Mutualisms can improve the acquisition of water, nutrients, and places to live. 3 Mutualisms can facilitate: • Pollination • seed dispersal
How can life respond?
1. Populations or species may decline or go extinct 2. Individuals within a species may acclimate 3. Species ranges may shift 4. Populations of species may evolve
The manager of a white-tailed deer population surveyed the population 2 years in a row, counting the number of females. (Note: Often in wildlife management, only females are tracked.) She counted: • 196 in year 2020 • 232 in year 2021
1.2
if predator needs to consume 20 prey individuals to produce 1 predator baby, then b =
1/20 or 0.05
Based on the performance curve of a species, the Tmin is 10, Topt is 30, and Tmax is 40 degrees. What is the tolerance range for this species?
30
A population of tigers has a carrying capacity (K) of 10,000 and r = 0.2 The current population size is 8,000. At this instant, how many net tigers will be added (or subtracted) from the population? In other words, what is the instantaneous growth rate at a population size of 8,000?
320
The manager of a white-tailed deer population surveyed the population 2 years in a row, counting the number of females. (Note: Often in wildlife management, only females are tracked.) She counted: • 196 in year 2020 • 232 in year 2021 If the deer population continues to grow at this rate, what will be the size of the population of female deer in 5 years (in year 2026)?
539
A population of zebras has a carrying capacity (K) of 10,000 and r = 0.4 The current population size is 2,000. At this instant, how many net zebras will be added (or subtracted) from the population? In other words, what is the instantaneous growth rate at a population size of 2,000?
640
If there are 200 cheatgrass plants in a single plot of land at year 5 and the population is growing with a finite rate of increase (λ) of 1.2, approximately how many plants were in the initial invasion at time zero? Assume geometric growth.
80
Cheatgrass is an annual grass plant native to Eurasia that was unintentionally introduced into the Great Basin area of Utah and Wyoming. During the colonization phase of cheatgrass invasions, this exotic species often exhibits geometric growth. If there are 150 cheatgrass plants in a single plot of land at year 6 and the population is growing with a finite rate of increase (λ) of 1.6, approximately how many plants were in the initial invasion at time zero?
9
A local population of Japanese beetles is growing geometrically with λ = 1.1 (per year). The population on July 31 this year consists of 800 adults. How many adults will be in this population on July 31 in TWO years?
968
What is the best (broad-sense) definition of symbiosis? A: an intimate interaction between different species that is beneficial to one species, and can be beneficial, detrimental, or neutral to the other species B:a short-term interaction between two species C: an intimate interaction between different species that must be mutually beneficial
A
Symbiosis
A close relationship between two species that benefits at least one of the species. Mutualism, communalism, or consumer resource
global worming
A gradual increase in average temperature
Lotka-Volterra Model
A model of predator-prey interactions that incorporates oscillations in the abundances of predator and prey populations and shows predator numbers lagging behind those of their prey
Lithosphere
A rigid layer made up of the uppermost part of the mantle and the crust. Lithosphere: rock, dirt, minerals of Earth's crust and uppermost mantle: Common indices of change • Sub-surface ground temperature • Isotopic signatures of stalactites and stalagmites • Width of annual bands of stalactites and stalagmites
atmosphere
A thin layer of gases surrounding Earth Common indices of change • Average surface air temperature • Extreme (minimum and maximum) surface air temperature • Temperature of different atmospheric layers • Wind speed • Circulation patterns
Which of the statements about greenhouse gases and the greenhouse effect is/are true? one example of longwave radiation is infrarred one example of shortwave radiation is UV light A: Most greenhouse gases are transparent to shortwave solar radiation, but absorb longwave thermal radiation B: The greenhouse effect is caused by multiple greenhouse gases, including carbon dioxide, water, and methane C:,Most greenhouse gases are very effective at reflecting shortwave solar radiation back into space D:The greenhouse effect may cause energy to be transferred back and forth between the Earth's surface and the atmosphere multiple times before escaping into space
A,B,D
Albedo
Ability of a surface to reflect light
Sexual reproduction is considered more costly than asexual (=clonal) reproduction because (in general): Select all that apply A: Sexually reproducing individuals spend half their reproductive budget producing males, which cannot reproduce by themselves. B: Sexual organs require energy and resources. C: Mating behaviors require time and energy D: Mating behaviors may increase the risk of herbivory, predation, and parasitism
All of them
Hydrosphere
All the water at and near the surface of the earth, 97% of which is in oceans Hydrosphere: all surface and subsurface liquid water on Earth: • includes water vapor and clouds • excludes frozen water (the cryosphere) Common indices of change • Ocean heat content • Sea surface temperature • Sea level • Total annual precipitation • Drought severity • Storm frequency/intensity
The leaf litter and root exudates of some Eucalyptus species are toxic to plants of other species, preventing their germination. This is an example of:
Allelopathy
predator
An animal that hunts other animals for food
Endotherms
Animals (such as birds or mammals) that can regulate their body temperature.
A trematode causes its fish host to swim closer to the surface of the water, making the fish easy targets for their avian predators. These trematodes rely on birds for completing their life cycle. A. the change in fish behavior is likely a host (fish) adaptation B. the change in fish behavior is likely a parasite (trematode) adaptation
B
Which of the following make up part of animal's fundamental niche? A: All of the choices B: The water conditions that it can grow and reproduce within C:Interactions between the animal and a competitor that affect its ability to grow and reproduce D:The effects of predation on the animal's survival
B
Which of the following statements relies on proxy data? E: Arctic sea ice area tracked since ~1980 exhibits a decreasing trend A: Mean global sea level has risen over the past 130 years B:None of the the statements in this list rely on proxy data all of the statements in this list rely on proxy data C:Mean atmospheric CO2 concentrations have increased since 1960 (measured in Hawaii) D:Mean global surface temperatures have increased, on average, over the past 150 years
B
Which of the following is an example of an Allee effect (positive density dependence)? A. A highly virulent and fast-spreading fungal disease causes the collapse of a population of cave-dwelling bats. B. Mountain lions cause the decline of a bighorn sheep population that is too small to effectively watch for predators. C. A butterfly population declines when its host plant (on which it lays eggs) is displaced by non-native (introduced) plants. D. A frog population's reproductive success drops drastically when the water in its habitat is contaminated with toxins.
B. Mountain lions cause the decline of a bighorn sheep population that is too small to effectively watch for predators.
behavioral animal defense
Behaving in ways that minimize risk from predation
Interspecific competition will be greatest in which of the following circumstances?
Between species that share identical resource requirements
In which of the following types of mutualisms, is the extinction of one partner likely to cause the extinction of the other? A. The interaction is facultative, and both partners are generalists B. The interaction is obligate, and both partners are generalists C. The interaction is obligate, and both partners are specialists D. The interaction is facultative, and both partners are specialists
C
Projections of future climate change vary widely. What is the primary source of uncertainty for how much Earth's climate will warm by the end of the century? A: Uncertainty from natural variability in the climate system (El Niño/La Niña cycles, volcanic eruptions, etc.) B: Climate response uncertainty, which is uncertainty about how to model feedbacks and other aspects of the climate system C: Emissions uncertainty, which is uncertainty about how extensively people will use fossil fuels in the future
C
What is the key evolutionary concept that underlies the Red Queen hypothesis? A: Through sex and genetic recombination, hosts are able to stop evolving and still maintain high fitness. B: Through sex and genetic recombination, hosts prevent evolution of pathogens. C: Through sex and genetic recombination, host populations are effectively a moving target for rapidly evolving pathogen populations. D:Through sex and genetic recombination all members of the host population become genetically identical E:That running increases fitness
C
What is the key evolutionary concept underlying the Red Queen hypothesis? A. Through sex and genetic recombination, hosts are able to stop evolving and still maintain high fitness. B. Through sex and genetic recombination, hosts prevent evolution of pathogens. C. Through sex and genetic recombination, hosts present a moving target for evolving pathogens. D. All of the above are true.
C
Which of the following is/are true statements? A: Both answers are false B: above 4°C water volume decreases as its temperature increases. This has contributed to sea level rise. C:above 4°C water volume increases as its temperature increases. This has contributed to sea level rise
C
Which of the statements about greenhouse gases and the greenhouse effect is false? one example of longwave radiation is infrarred one example of shortwave radiation is UV light The greenhouse effect may cause energy to be transferred back and forth between the Earth's surface and the atmosphere multiple times before escaping into space A: The greenhouse effect is caused by multiple greenhouse gases, including carbon dioxide, water, and methane B: Greenhouse gases reradiate thermal energy as longwave radiation in all directions C: Most greenhouse gases are transparent to longwave thermal radiation, but absorb shortwave solar radiation
C
Lotka-Volterra Assumptions
Closed system (one predator, one prey, no immigration) No refuges for prey No handling time for predators Prey grow exponentially in the absence of predators Predators consume infinite amounts of prey
What is "b" in the lotka-volterra model?
Conversion rate (converts encounter rate to number of new predators produced)
As populations of predators grow, their resources (prey) become scarcer. Thus, from the perspective of the predator population, the availability of resources (prey) is:
Density dependent (=dependent on the density of the predator)
Climate data are usually reported as anomalies
Difference between a measured value and its baseline or reference (many times a long-term average).
Primary source of uncertainty in projections of warming
Emission uncertainty (usually due to humans)
Can other biotic interactions affect the outcome of competition?
Example: Spadefoot and southern toads are more active and forage more than spring peepers. When placed in a pond without predatory newts, the spadefoot and southern toads outcompeted the peepers. When placed in a pond with newts, the high activity of the toads allowed the predators to more easily find them, allowing the less active peepers to dominate.
Two species compete for a common resource eventually leading to concentrations of that resource that are so low that only one of the species survives. This is an example of:
Exploitative or resource competition
Assuming that resources remain unlimited for the prey population, what will happen if the prey consumption term (a Npredator Nprey) is removed from the Lotka-Volterra prey equation?
Exponential growth of prey
A species of pitcher plant survives longer when there's a higher than lower cloud cover. Cloud cover is a resource for this species.
False, cloud cover cannot be consumed or monopolized
positive feedback
Feedback that tends to magnify a process or increase its output.
Cryosphere
Frozen water on earth Cryosphere: all frozen water on Earth, including that in frozen soil (permafrost) Common indices of change • Mass/volume of ice sheets and glaciers • Snow cover extent • Sea ice extent • Permafrost extent
An ecologist finds two similar fish species that live in lakes, a pink fish that lives in deep water where it is colder and a purple fish that lives in shallow where it's warmer. The ecologist hypothesizes that these two fish compete with each other, with the purple fish outcompeting pink fish but not able to survive in colder temperatures in deep water. Which of the following would be the best experiment to test whether the fish are in competition?
Grow both fish species alone in both deep and shallow lake plots. Also grow both species together in both deep and shallow lake plots.
Nutritional Plant defenses
Growing structures that are less nutritious for grazers (have less N and P)
having more offspring can affect the parents how
Having more offspring can stimulate parents to hunt harder for food to feed their offspring. This additional effort can affect the parent's fitness.
Anthropogenic
Human-induced changes on the natural environment
Interference Competition/Direct competition
In direct competition, the species interact with each other and directly influence the resources available in the ecosystem. Ex:For example, the giraffes compete when the leaves become scarce.
How does instantaneous growth rate change with population size?
In logistic growth, a population's per capita growth rate gets smaller and smaller as population size approaches a maximum imposed by limited resources in the environment, known as the carrying capacity ( K). the growth rate is highest whent he population is at medium size
Resource Competition/Exploitative competition/Indirect competition
Indirect competition occurs when organisms use the same resource, but don't necessarily interact with each other Ex:Zebra present near the pond might affect other zebras that occur away from the pond by decreasing the amount of water in the river. This is a form of indirect competition where the species do not interact with each other but are related by means of a resource.
"slow" life history
Long time to sexual maturity Long life spans Low numbers of offspring High parental investment Examples: elephants, oak trees
Some species of bees imitate the coloration of wasps, and vice versa; their coloration and patterns are very conspicuous. Both can sting predators. These bees practice (or use): (select all that apply)
Müllerian mimicry
The Competitive Exclusion Principle states that:
No two species can occupy the same niche in the same environment for a long time
If prey suddenly became substantially less abundant leading many individuals of the predator population to suddenly die of starvation (other causes of mortality do not change), which parameter(s) in the Lotka-Volterra predator equation would change:
Nprey
reciprocal selection
Occurs when two species both exert pressure on the other through natural selection.
Topt
Optimal range of temperatures (when performance is greatest)
Evidence for attributing recent changes in Earth's climate to human activity
Over the past 150 years human activities have released increasing quantities of greenhouse gases into the atmosphere. This has led to increases in mean global temperature, or global warming. Other human effects are relevant—for example, sulphate aerosols are believed to have a cooling effect.
trophic mismatch example
Plant emergence is directly affected by climate change. • Caribou population is indirectly affected by climate change because its interaction with the plant population (or community) is altered. • Caribou calving and plant emergence have become increasingly asynchronous as temperatures have climbed. This mismatch is also known as trophic mismatch
The Lotka-Volterra model has several unrealistic assumptions. Which of these is an assumption of Lotka-Volterra?
Prey refuges do not exist
Coevolution
Process by which two species evolve in response to changes in each other It means that they evolve by natural selection imposed by each other. In other words, reciprocal adaptation Although coevolution can occur as a result of mutualistic interactions, it might be faster and more evident in antagonistic interactions, which can lead to an evolutionary arms race
Indirect effect
Reproductive success of Greenland caribou is improved when calving is synchronized with plant emergence and plant emergence is due to higher temperatures due to climate change Plant emergence is cued by temperature while caribou calving is cued by day length
Phenology
Seasonal timing of plant and animal life history events. For example: What day of the year they: • initiate migration • They initiate reproduction: mating, flowering, give birth • They emerge from dormancy or hibernation
"Fast" life history
Short time to sexual maturity Short life spans High numbers of offspring Little parental investment Examples: fruit flies, weeds
Proxies (isotopic signature in ice)
Snow formed in colder temperatures has comparatively less 18O
range shifts
Species are relocating to areas with more tolerable climate conditions Limitations: • There may be no more higher latitude or higher altitude habitat available • Some species may not be able to move fast enough across the landscape to avoid extinction. • Communities don't move; species do. Altered communities and their dynamics. • For example: A herbivore moves fast enough, but its plant resource doesn't
Hottest Earth summer on record
Summer of 2023
Territoriality vs Preemption
Territoriality is usually an active form of competition while preemption is passive
In the Lotka-Volterra predator-prey equations, the parameter rprey is:
The intrinsic growth rate of the prey population
trophic mismatch
The lack of synchrony between the phenology of consumers and that of their resources
Storm-petrels live 30 to 40 years. Thrushes rarely live beyond 3 to 4 years. Even if you knew nothing more about the life histories of these two species, make an educated guess about which species has the longer pre-reproductive period.
The longer-lived species (storm-petrel) probably has the longer pre-reproductive period.
Goldenrod typically outcompetes other plants in fields because of its fast growth and allelopathic properties. Every few years there's a population explosion of insects that only consume goldenrod plants. What happens during these insect population booms?
The outcome of competition is reversed, and other plants dominate goldenrod
The fundamental niche describes:
The potential environmental conditions tolerated by a species
What is the greenhouse effect?
The process by which gases hold heat in the atmosphere Long wavelength is absorbed by the greenhouse gasses molecules causing them to get excited and vibrate, when they stop virbrating the shoot the radiation in all directions, this means that the radiation goes back and forth between the surface and atmosphere multiple times before it can escape.the strength of the greenhouse effect has to do with the amount of gasses in the air, such as more methane because methane absorbs more infared heat
Allelopathy
The production of chemicals by plants that inhibit the growth of neighboring plants
The keeling curve (example)
Timeplot of increase of atmospheric Carbon Dioxide (CO2) concentrations relative to the pre-industrial CO2 long-term mean value of 278ppm. During 2021, atmospheric CO2 concentrations reached a record-level increase of 50% relative to pre-industrial CO2 levels. Current values > 400 ppm
Passive transmission
Transmission into the host that requires no action from the parasite -hairworm waiting for cricket to drink water
Active transmission
Transmission into the host that requires the parasite to actively work to gain entry into the host -lamprey swimming around looking for fish to attach to
direct transmission
Transmission of blood or body fluids through touching (including shaking hands), kissing, coughing, sneezing, and talking.
Cacti grow in arid climates, and need a certain amount of water in order to flower. Water is a resource for cacti. (choose the best answer)
True, water increases population growth and can be consumed or monopolized
Forcings responsible for glacial-interglacial (=Milankovitch) cycles
Variations in Earth's orbit through time have changed the amount of solar radiation Earth receives in each season
Tipping points
a critical threshold when a small change can have potentially drastic effects. Mostly linked to climate change and pollution and the increase in the emmition of greenhouse gases
Feedbacks
a feedback is the process by which a system is changed or controlled by the output or product it produces
Keeling Curve
a graph made over the span of 50 years that shows the increase of carbon dioxide
Bastesian mimicry
a palatable or harmless species mimics warning colors of an unpalatable or harmful model this is dishonest/deceptive signaling
Red Queen Hypothesis
a species must adapt and evolve not just for reproductive advantage, but also for survival because competing organisms also are evolving
Generalist
a species that interacts with many other species
Specialist
a species that interacts with one other species or a few closely related species.
Tolerence Plant Defenses
adaptations to regrow quickly after being grazed
tolerance plant defense
adaptations to regrow quickly after being grazed
Mutualism can
aid in defense Ant living in plants and protect the plant Cleaner fish clean parasites off of fish and receive a meal algae that grows in coral
Based on the final map, did sea surface temperatures or air temperatures over land increase more?
air temperatures over land
Symbiosis can include which of the following? Select all that apply A: mutually beneficial intimate interactions between two different species B: intimate interactions between two species that are beneficial to one partner and detrimental to the other C: a consumer-resource interaction in which the consumer quickly kills the resource D: intimate interactions between two species where one species obtains a benefit and the other is unaffected
all except C
deterministic
always resulting in a particular pattern the output of the model is fully determined by the parameter values and the initial conditions.
Acclimation
an organism's change in response to a change in the organism's environment limiations: can only chanage to a certain point
Resource
anything an organism consumes or uses that causes an increase in population growth rate when it becomes more available (and vice versa). Ecological factors that cannot be consumed, and thus monopolized (e.g., temperature), are not considered resources.
horizontal transmission
anything different from vertical (from the environment; from other individuals; from other species)
Suppose you are studying coyotes and wolves, and you determine that wolves are experiencing a reduction in their population that can be attributed to a contagious pathogen that the coyotes carry, but that it is more harmful in wolves. Suppose also that there are an excess of prey items for coyotes and wolves. The observed reduction in the population of wolves is an example of:
apparent competition
Suppose you are studying zebras and giraffes, and you determine that zebras are experiencing a reduction in their population that can be attributed to a virus the giraffes carry that is more harmful in zebras (assume there are plenty of grasses to feed the current populations of both species).
apparent competition
Because of its relationship with its host, the endoparasite
as high exposure to the host's immune system
When one competitor exploits a resource more efficiently and the other competitor is better at tolerating stressful conditions or avoiding consumers, such that the two competing species coexist locally in different microhabitats, this phenomenon is known as __________ competition.
asymmetric
Why do regional differences exist in measuring sea level?
because of natural variability in the strength of winds and ocean currents, which influence how much and where the deeper layers of the ocean store heat.
geometric vs exponential growth models
both assume: unlimited resources and constant birth and death rates
Crypsis Animal Defense
camouflaged colors, shapes, and other ways of hiding from predators
crypsis
camouflaged colors, shapes, and other ways of hiding from predators
interspecific competition
competition between members of different species (both closely and distantly related) Ex: Hyenas and lions fighting for food
intraspecific competition
competition between members of the same species Ex: two lions fighting for territory
Herbivore
consumer of plants
negative forcing
cools the surface
If b decreases but all else stays the same, what happens to predator population growth (dN/dt)?
decrease
f the search efficiency of a predator (a) became larger, but all else stayed the same, what would happen to prey population growth?
decrease
ocean acidification
decreasing pH of ocean waters due to absorption of excess atmospheric CO2 from the burning of fossil fuels. CO2 is disolved in water and creates a compound that decreases the pH of the ocean -higher acidity causes calcium carbonate to dissolve in the ocean which negativitly affect coral and intertabrates that sue the calcium to build there shell
Factors that impact a population, according to the size of the population are called: In other words, factors that have a different impact on the population, depending on the size of the population are called:
density dependent factors
Temperature performance curve
describes how hte expression of a particular trait (growth rate, movement rate, catalytic rate for enzyme) varies with temperature
physical animal defense
developing physical barriers to predation
Physical Animal Defense
developing physical barriers to predation -shells
mechanical plant defenses
developing structures like thorns that make it harder for animals to eat them
Vertical transmission of parasites is
direct transmission from parent to offspring
symmetric competition
each species experiences a roughly equal decrease in fitness
Disturbances
events that change communities, remove or destroy organisms from communities, or alter resource availability Ex: Longleaf pine trees once dominated forests in the southeastern United States with grassy understories. Plants in this type of forest relied on frequent, low-intensity fires to exist. Throughout the twentieth century, fires were suppressed in many forests, allowing other plants to increase and outcompete the plants adapted to fire.
A population of sharks is determined to have an exponential rate of increase of r = 0. What is the corresponding value of λ for this population?
exactly 1
innate
existing from birth, inborn
Solor activity doesn't
explain temp increase
climate forcing
factor that can effect earths climate
Density dependent
factors that affect population size (specifically the per capita growth rate) in relation to the population's density, per capita growth rate
density independent factors
factors that have to same effect of small and large populations
When two species provide fitness benefits to each other but do not require each other to persist, they are
facultative mutualists
Milankovitch cycles are explained by variation in solar output (such as sunspots)
false
Temperature reconstructions for the Northern hemisphere based on tree rings support that the hypothesis that the last 30 years have been cooler than any 30-year period in the last 800 years.
false
life history traits
fecundity, parity, parental investment, longevity
Geometric growth (lambda)
finite rate of increased growth rate (estimated growth rate)
vertical transmission
from parent to child
The ___________ niche is the complete set of conditions under which an organism could potentially survive and reproduce.
fundamental
Ectomycorrhizal fungi (mutualistic)
fungi characterized by hyphae that surround plant roots and enter between root cells but rarely enter the cells. providing their hosts with soil nutrients and water in exchange for plant carbon.
endomycorrhizal fungi (mutualistic)
fungi characterized by hyphal threads that extend far out into the soil and penetrate root cells between the cell wall and the cell membrane roots provide carbohydrate for the fungi and the fungi transfer nutrients and water to the plant roots
endophytic fungi (Plant defense)
fungi that live inside a plant's tissues Endophytic fungi produce chemicals that repel herbivores and provide drought resistance by increasing the concentration of minerals in plant tissue.
Mycorrhizal fungi (mutualistic)
fungi that surround plant roots and help plants obtain water and minerals
Assume that a population of ungulate mammals, such as elk, breed only in the spring and are unrestricted by resources or other factors. Which is the best suited growth model for this type of population?
geometric
Direct evidence of climate change
greenhouse mechanism observed in atmospheric molecular function average higher temperatures and more rainfall
nutritional plant defenses
growing structures that are less nutritious for grazers (have less N and P)
How to test competition?
growing to species separate and seeing how they do then growing them together, if one dominants the other it is considered competition
If we remove the prey consumption term (a Npredator Nprey) from the Lotka-Volterra prey equation, but resources remain unlimited, what happens to the prey population?
grows forever
Because of its relationship to its host, the ectoparasite generally has
high exposure to its natural enemies and the external environment low exposure to the host's immune system
High vs mid-latitudes
high latitude are warming more
Assume mountain lions eat deer or rabbit. You would expect the conversion rate (b) to be ________ when they eat a deer as compared to when they eat rabbit.
higher
Direct effects
higher temperature higher CO2
Tmax
highest temperature above zero
performance
how effectively on individual o rpopulation executes a given biological task
What causes sea level rise?
ice melt and thermal expansion
If the search efficiency of a predator became smaller, but all else stayed the same, what would happen to prey population growth?
increase
When adults have a low probability of survival from one year to the next (for example in a high predation environment), and survival of the juveniles (young) is relatively high, what life history will natural selection tend to favor:
increased fecundity at the expense of adult survival.
Pyramids with narrow bases
indicate a declining population.
Age structure pyramids with broad bases
indicate a growing population.
Pyramids with straight sides
indicate a stable population.
interference competition
individuals interact directly with one another by physical force or intimidation
N(o)
initial population size
dN/dt
instantaneous growth rate
Preemption
is interference competition that occurs when an individual prevents other individuals from occupying a location by occupying the space first
Trade-off lady bug
it cost more energy to make the alkaloid toxins so when there is more food they produce more toxins
Logistic growth (know K)
k is the carrying capacity
If a fish invest more time in growing then the offspring will be
less in number but higher quality embryo
Which model(s) take into account density dependence?
logistic model
Mimicry Animal Defense
looking, sounding, or in other ways mimicking a species that predators avoid
mimicry
looking, sounding, or in other ways mimicking a species that predators avoid
Tmin
lowest temp. at which performance is above zero
Indirect evidence of climate change
melting glaciers, destruction of coral reefs and increased flooding
Warm air can hold ______ water vapor than cold air
more
what is "m" in the lotka-volterra model?
mortality rate of predator (independent of prey availability)
Limitations of evolution
most mutations are bad it takes time to evolve drift decreases genetic variation
what is the ultimate source of genetic variation
mutation
lambda vs r: lambda
name: finite rate of increase used to model: discrete populations measures: gorwth compounding at constant intervals -what is it?: equivalent to net birth rate per individual over discrete time period estimated by: = N(t+1)/N(t) population does not change when: =1 population increases when: >1 population decreases when: <1 to convert lambda to r: r = ln(lambda)
lambda vs r: r
name: per capita growth rate used to model: continuous generations measures: growth compounding continuously what is it?: per capita difference between birth and death rates during a fixed time period estimated by: ln(lambda) population does not change when: = 0 population decreases when: >0 popualtion decreases when: <0
Trade-off nicotine
nicotine is only produced when then plant is harmed and it cost energy to make to nitoctine and rpair the plant so they grow slower probably
competative exclusion principle
no two species can occupy the same niche in the same habitat at the same time
Southern vs northern hemisphere
northern is warming more
In a population growing according to the exponential growth model, population size is ______
not limited
Consider a species of fig tree that is pollinated by a single species of wasp. Without that wasp species, the fig tree will not produce seeds. Without that species of fig tree, the wasp will not produce offspring. The relationship between these species is an example of
obligate mutualism
asymmetric competition
occurs when one species suffers a much greater fitness decline than the other
Ectosymbiosis
one organism remains outside of the other
Ectosymbiont
organism located on surface of another organism (usually larger)
endosymbiont
organism located within another organism
resource competition
organisms compete indirectly through the consumption of a limited resource
Ectotherms
organisms whose body temperatures are determined by their surrounding environment
why is it easier to combat bacterial diseases in humans than in protozoans because
parasites are more closely related to humans than bacteria
Biosphere
part of Earth in which life exists including land, water, and air or atmosphere Common indices of change • Length of growing season • Species ranges (population size and location) • Phenology: seasonal timing of animal an plant life history events (reproduction, migration, hibernation, etc.) • Extinctions • Changes in the carbon cycle
Negative density dependence occurs when the ______
per capita population growth rate decreases as population becomes larger.
what is r
per capita rate of increase (intrinsic growth rate) r=ln(lambda)
proxies of climate change
pollen and faunal assemblages (environmental), biomarkers (e.g. plant wax), dust, and carbon isotope ratios for precipitation, tree rings... Ex: tree rings grow more when the temp is warmer
The age structure of a population is often represented by a pyramid. What does an age structure pyramid with a broad base and a narrow top indicate about a population?
pop is growing
N
population size
N(t)
population size at time (t)
N(t+1)
population size at time (t+1)
In a study of a particular plant species, populations with fewer than 100 individuals had substantially reduced fecundity (fewer fruits per flower and fewer seeds per fruit), than larger populations. This is an example of
positive density dependance
A species of louse (an external parasite) infests salmon. Researchers have found that the lice have difficulty finding a mate when there are only a few lice on an individual fish. The lice find mates more easily and produce more offspring when there are many lice on an individual fish. This is an example of ______
positive density-dependent population regulation.
Consumer
predator, herbivore, parasite
Resources
prey, plant, host
Attributions
process of determining the probable causes of an observed phenomenon
Chemical plant defences
producing chemicals that are noxious or poisonous to herbivores
Chemical Animal defenses
producing chemicals that are noxious or poisonous to predators -frogs skin
chemical defense
producing chemicals that are noxious or poisonous to predators or herbivores
Some time after the Eurasian species cheatgrass first invades a new prairie in the western U.S., its population enters what is known as a "naturalization" phase. Increased plant density and resource utilization mean that the population enters a period of logistic, rather than geometric, growth. Assuming a value of λ of 1.6 as before and a carrying capacity of 2000, what is the per capita growth rate when the population is A. N = 800 B. N = 1000 C. N = 2000
r=0.47 A: 0.282 B:= 0.235 C:0
Below is a graph of a Paramecium population growing in culture in a petri dish for 20 days If the availability of food is the one factor limiting the population's growth, adding a finite amount of additional food will:
raise the carrying capacity
Stochastic
randomly determined Stochastic models have some inherent randomness. The same set of parameter values and initial conditions will lead to an ensemble of different outputs.
Tolerence range
range of temperatures where performance in above zero -range between Tmin and Tmax
abNpreyNpredator describes
rate at which new predators are added to the predator population
Many species exhibit logistic growth in nature. At what point on a logistic growth curve is intraspecific competition the strongest?
reaches close to carrying capacity
The __________ niche is the subset of the fundimental niche describing the conditions, under which an organism actually lives, given limitations created by interactions with other species.
realized
having more young can
reduce the chances of offspring survival because the amount of parental care per offspring will decrease
Two pathogen species infect the same host species. Each pathogen species reduces the availability of resources from the host organism for the other, but does they do not interact with each other in any other way. Thus, we can refer to the interaction between the two pathogen species as one involving __________.
resource competition
Logistic growth model
resources are limited and is continuous
The global mean sea level has
risen about 8-9 inches (21-24 centimeters) since 1880.mostly due to a combination of melt water from ice on land (glaciers and ice sheets) and thermal expansion of seawater as it warms.
Coral bleaching events caused by
rising temperatures
what is "a" in the Lotka-Volterra Model
search efficiency or attack rate on a predator If there was constant attack (extremely high search efficiency) this would be 1.
How do host keep up with there evolving parasite?
sexual reproduction allows for new combinations of genes which some can counter the effects of the parasite additionally they are typically better at copying with environmental changes Offspring with genetic variation resulting from sexual reproduction have an increased probability of possessing gene combinations that will help them adapt to different conditions (a "diverse portfolio" where at least some combinations will survive. However, environment (abiotic) does not co-evolve with the organism.
"Hockey Stick" graph of temperature change
shows temperature change over the past 1700 years and the temp in increasing
Endosymbiosis
symbiosis in which one of the symbiotic organisms lives inside the other. Think of fly and spiroplama (it is mutualism with a predator and commensalism without)
fundamental niche
the complete set of conditions under which an organism could potentially survive and reproduce
Age structure
the distribution of individuals among age classes (=age categories) within a population
long wave radiation
the energy radiating from the Earth surface after warmed by the short wave lengths
Territoriality
the establishment of an area by one or more organisms from which other are at least partially excluded
Longevity (life expectancy)
the life span of an organism.
Fecundity
the number of offspring produced by an organism per reproductive episode.
parasite load
the number of parasites of a given species that an individual host can harbor
Parity
the number of reproductive episodes an organism experiences.
principle of allocation
the observation that when resources are devoted to one body structure, physiological function, or behavior, they cannot be shared to another. no organism possesses the best of all life history traits There is a common tradeoff between offspring number and offspring survival. Organisms face trade-offs; when one life history trait is favored, it prevents the adoption of other advantageous traits. Resources such as nutrients or energy that an individual invests in one process cannot also be invested in other processes, meaning that not all life functions can be simultaneously maximized.
negative feedback
the process is slowed or stabilized by the product or output of the process
Life history
the schedule of an organism's growth, development, reproduction, and survival; represents an allocation of limited time and resources to achieve maximum reproductive success.
Climatological fingerprint
the specific spatial and temporal response pattern a given climate forcing is expected to produce
realized niche
the subset of fundamental niche describing the conditions, under which an organism actually lives, given limitations created by interactions with other species (where the species actually lives)
Parental investment
the time and energy given to an offspring by its parents.
Climatologists have identified two important factors contributing to sea level rise. One is the increase in water volume from melting snow and ice on land. Which of the following has also been shown to be a key factor driving sea level rise?
thermal expansion
How do the species prevent cheating in mutualistic relationships?
they develop ways to counteract the cheating Ex: Moth and yucca plant
How do parasites keep up with there evolving host?
they tend to reproduce quickly and have larger populations allowing for mutation to occur more frequently
Aposematism confers a honest signal
true
Batesian mimicry confers a dishonest signal
true
Lotka-Volterra model is deterministic
true
Milankovitch cycles are explained mainly by variation changes in the Earth's orbit
true
Mullerian mimicry
two or more unpalatable species resemble each other Ex: bee and wasp honest signaling
Obligate mutualists:
two species that provide fitness benefits to each other and require each other to persist.
Facultative mutualists
two species that provide fitness benefits to each other, but the interaction is not critical to the persistence of either species.
Geometric growth model
unlimited resources and population have discrete breeding season/generations, such as one breeding season per year
Exponential growth model
unlimited resources that does NOT have discrete generations and is continuous
positive forcing
warms the surface
Aposematism
warning colors, sounds, or other characteristics to alert predators that this prey will not be tasty
Aposematism Animal Defense
warning colors, sounds, or other characteristics to alert predators that this prey will not be tasty
Four main greenhouse gases
water vapor, carbon dioxide, methane, nitrous oxide
short wave radiation
wavelengths of radiation emitted by the sun, especially ultraviolet, visible, and short infrared radiation Comes from the sun and easily passes through Earth's atmosphere and warms earths surface (does not interact with earth gasses)
apparent competition
when a species has a negative effect on another species through an enemy - including a predator, parasite, or herbivore not competition because it is not mediated through a resource
Growing population (lambda)
when lambda is greater than 1
shrinking population (lambda)
when lambda is less than 1
Negative density dependence
when the per capita growth rate decreases as population density increases (what the logistic model captures with the use of K). the most common factors that cause neg density dependence are limiting resources (food, nesting sites, physical space) As a population's size increases, resources are divided among more individuals, and per capita resources decline to a level at which individuals find it difficult to grow and reproduce. Crowded populations can also generate stress, transmit disease, and attract predators.
Negative density dependence
when the per capita growth rate decreases as population density increases.
Positive density dependence
when the per capita growth rate increases as population density increases (also known as Allee effect). typically occurs when population densities are low, which may make it hard to find mates, particularly when sex ratios are uneven. Ex: when a school of fish is too small they cannot defend themselves, so when population density is decreasing, per capita growth rate is decreasing
Do differences in life expectancies correlate with aspects of life history?
yes
Assume: 1. Staphylococcus grow exponentially 2. r = 1.386 h-1 (= 1.386/hr) 3. Initial inoculation = 2 cells How many cells will there be after 12 hours?
~ 33,400,000 cells
r-selected organisms
~ fast life history, The label r-selected describes these species, because their life histories maximize potential growth rate, r.
K-selected organisms
~ slow life history, These species are labeled K-selected because they are highly competitive and survive well at population sizes close to carrying capacity, K
Exponential growth lambda and r
λ is the contribution of an individual to the total population size, whereas r is the contribution of an individual to the rate of change in population size.
Why do lynx populations boom later than hare populations?
• Intervals between birth and sexual maturity in both populations • Influence of prey availability may not be felt strongly in predator population, until young born that year are themselves reproductively mature
Phenology Cues
• Photoperiod = "length of day" • Temperature • Precipitation
The same principles of evolution (and evolution by natural selection) apply to co-evolution
• genetic variation for the trait is present in the population • the trait is heritable • the trait confers a fitness advantage
