Eco/Evo E3: 3/29+ (q3 up to 91)
rescue effect
extinction events could be masked if the sub-population is re-colonized by a source of the same species
primary producers
autotrophs
growth rate
r = dN/dT
Metapopulation of Sinai baton blue butterflies: make a list of questions / biological information that would assist in conversation.
*which areas of the metapopulation have the highest growth rate, and why? *which populations are locally extinct? *which populations are supported by rescue effect? Sink→negative growth rate r Source→ positive r
Why won't you see coevolution in commensalism?
+/0 : one species is not effected by the other
DNA Mark Recapture
-bear dung -set up rotting meat with barbed wire, collects DNA samples from hairs. identify all the individuals, then do it again! see who comes...
In order for a trait to evolve through natural selection, the trait must help ...
... some individuals survive and reproduce better than others
1) Bears have relatively (large /small) offspring compared to many other species. 2) Because of this, they have (many / few) offspring at a time. 3) Because of this, bears should provide (a lot of / very little) parental care to their offspring. 4) Because of this, infant mortality in bears is (relatively high /relatively low) compared to other species. 5) Name one other life history characteristic that you would expect to find in bears 6) Bears are a type (K / r) strategist.
1 large, 2 many, 3 a lot of, 4 relatively low, 5 late maturation rate, 6 K
Why is dark skin favored at low altitudes?
1) Folate Levels, 2) Thermo-regulation, 3) Immuno-regulation, 4) Effective foraging and hunting, 5) Skin permeability, 6) Skin cancer protectant
Describe 2 ways in which deforestation leads to increases in CO2 in the ATM
1) Trees take in CO2 and release oxygen through terrestrial photosynthesis 2) When you burn the trees or they decompose, that carbon ends up in the oxygen 3) When you plow a field, free carbon comes into contact with oxygen and gives off CO₂
Why is light skin favored at high altitudes?
1) Vitamin D provision 2) Thermo-regulation
characteristics of zebra mussel questions, in class worksheet last week
1) generalist, high reproductive potential 2) they eat phytoplankton 3) can live in fresh and brackish water, free swimming larvae, females release more than 1 million eggs, get maturity soon, and have a long lifespan in comparison 4) the quagga outcompete the zebra mussels in the great lakes 5) no. increase species diversity 6) 7) 8)
each potential solution
1) protect forests, caps on use, introduce new invasive species, disease, antibiotics, cap on pollution 2) impact on industry, demand stays same, trade one problem for another, resistance, demand stays the same,
photosynthesis and respiration
6CO₂ + 6H₂O ↔ C₆H₁₂O₆ + 6O₂
K strategy versus r strategy
A K strategist (K for carrying capacity) has a population size close to their carrying capacity; they live long lives. An r strategist, like flies, tend NOT to hit their carrying capacities. They typically live in variable climatic conditions (ex. die off in winter). Instead of trying to make it to K (carrying capacity) they try to maximize r and expand their population as much as possible when they can.
transmittance
A measure of the fraction of light that passes through a sample
14. What would happen to the reproductive success of:
A. a light skinned person living in the tropics? B. a light skinned person living in the polar region? C. a dark skinned person living in the tropics? D. a dark-skinned person living in the polar region? A lower, B higher, C higher, D lower (vitamin D, thermoregulation)
19. Taking ONLY vitamin D into consideration, what would happen to the reproductive success of: A. light skinned person in tropics B. light skinned person in polar region C. dark skinned person in the tropics D. dark skinned person in the polar region
A. higher, B. higher, C. higher, D. higher
Why do we care about population ecology?
Any type of organisms that we use for ourselves; fish. It can really help us to know how populations of fish grow over time so we can fish them and get food but not deplete their stocks and run out of fish. Invasive species- kudzu. It grows very quickly and over everything. It is important to know how it grows so we can control it. Spread of bacterial populations; disease
interspecific competition
Competition between individuals of different species
13. All other things being equal, which skin tone would you expect to be correlated with higher levels of folate?
Darker skin would have more Melanin and thus, less transmittance of UV light.
eutrophication
Enrichment of water by inorganic nutrients used by phytoplankton. Often, overenrichment caused by human activities leads to excessive bacterial growth and oxygen depletion.
evolution first
Evolution-first approaches seek to preserve genetic diversity, which can help all the world's species survive and adapt in fast-changing environmental conditions
How do they identify human accelerated regions?
Example: Compare chimp and monkey. See number of changes. Then, compare chimp and human; should be less random mutations in more recent ancestor. If there are many, than there is selection happening.
troposphere
First layer of atmosphere, 0-10 miles above Earth's surface. Contains weather, greenhouse gases, and bad ozone
Why does burning fossil fuels release CO2?
Fossil fuels are composed of organic material; old plants and algae.. CH₄ + 2O₂ →CO₂ + 2H₂O
Which do you like better out of evolution first, function first, or hotspot first, and why?
Function first; more efficient use of resources.
function first
Function-first forms of triage favor species that perform a unique job in nature, such as whitebark pines, which provide vital food for grizzly bears.
The ocean absorb between 25-40% all man-made carbon dioxide. Do you think this is good or bad for biodiversity?
Good for biodiversity; not in the atmosphere Bad for biodiversity; lowers oxygen content in the oceans, and changes pH; therefore edging out organisms that calcium carbonate
HAR1
Human Accelerated Region: highly changed region between humans and chimps, most dramatic is HAR1
20. Predict the skin tones expected at different latitudes, taking ONLY vitamin D needs into consideration.
If only vitamin D needs to be taken into consideration, there would be light skin everywhere but especially at the poles.
How do you determine if you have a metapopulation, as opposed to multiple closed populations or one contiguous population?
If there is gene flow but the growth rates of the subdivided populations are different, than you have a metapopulation.
random dispersion
Individuals are equally likely to occur in any spot in an area
uniform dispersion
Individuals spaced evenly in an area
4. Does the amount of UV light reaching the Earth vary in a predictable manner? If so, describe the pattern you observe.
It does vary in a predictable manner. It varies based on the orientation relative to the sun: the closer to the equator, the more UV radiation.
9. Based on this information, does that hypothesis about the evolution of skin color (Question 7) seem likely? Why or why not? How does skin color meet, or fail to meet, the three requirements of natural selection?
It doesn't have a strong selective pressure on reproductive fitness; the effect on being able to pass down genes is very little. Variation, heredity, and selective pressure with differential success are the three requirements.
What age does skin cancer typically occur?
It tends to occur later in life. Humans that live to age 65 are 50% likely to have had skin cancer at least once in their lives.
Why does survivorship always trend downwards for a life cohort table?
It's the proportion of the original.
survivorship curves, K vs. R
K: 1 or II r: III
Why are Caucasians more at risk?
Less melanin in their skin, so there is less protection against ultraviolet radiation. Melanin is a pigment produced by melanocytes in the bottom cell layer of the epidermis. Melanin production is increased on sun exposure, leading to higher levels which help prevent cellular damage due to UV radiation.
What is the biggest carbon reservoir?
Most are buried deep below the earth's surface.
greenhouse gases
Most significant:H₂O, CO₂, CH₄, CFC's. Trap outgoing infrared energy in the troposphere causing the earth to warm.
logistic growth
N = Pop size N₁ = Pop size @ year 1 r = per-capita growth rate t = time K = carrying capacity *growth stops when N = K
if bird's use day length as a cue for major life event,s you would expect that earlier warm spring weather would:
NOT change the date of laying
15. Can folate alone explain the variation and distribution of light/dark skinned individuals around the world?
No. Higher melanin isn't ideal for vitamin D production and thermoregulation at higher altitudes.
8. Review your answer to Question 3. Keeping your answer in mind, how strong a selective pressure do you expect skin cancer (UV-induced mutations) to exert on reproductive success?
Not that strong; it commonly occurs later in life after individuals have already reproduced and passed on their genes.
species richness
Number of species in a community.
ecosystem services
Our planets ecological systems that purify air and water, cycle nutrients, regulate climate, regulate climate, pollinate plants, and recycle our waste.
permafrost
Permanently frozen ground, usually occurring in the tundra, a biome of Arctic regions. Methane is frozen in the ice, when the ice melts the methane is decomposed in high amounts
metapopulation
Population subdivided into several small and isolated populations due to habitat fragmentation.
What causes skin cancer?
Skin cancer occurs when mutations occur in the DNA of skin cells; mutations of DNA that control the cell cycle and cause the cells to grow out of control and form a mass of cancer cells.
7. Hypothesize why different skin colors have evolved. Based on what you know, what factor is most likely to exert a selective pressure on skin color?
Skin cancer, Sun burns, Vitamin D
indicator species
Species that serve as early warnings that an ecosystem is being damaged. "canaries in the coal mine"
If you were a scientist studying grizzly bears in a wild, rugged mountain ecosystem, how would you count them?
Tag them with radioactive darts. Thermal imaging at night in quartets. Motion sensitive cameras Tranquilizer darts. GPS collars / radio collars
What cues do organisms use to time important events?
Temperature, daylength, moon.
If there are a lot of young people as a percentage of the population, what does that tell you?
That the population is growing quicker than a population with a more even spread.
11. Based on Branda and Eaton's results (Fig 3), what is the apparent effect of UV light exposure on blood folate levels? 12. What is the apparent effect of UV light on folate levels in the test tube?
The folate levels drop after UV light exposure. The numbers are almost halfed in the human population and in many of the test tube samples.
5.Based on these data, where might you expect to find the most lightly pigmented and most darkly pigmented people on the planet? Be as specific as you can.
The most darkly pigmented would be in equatorial Africa, The most lightly pigmented would be in the highest region
algal bloom
The overgrowth of algae produces large amounts of organic matter. As decomposers break down the organic matter, they use up the oxygen in the water resulting in death of aquatic life. Algae Blooms are caused by excess phosphorus and/or nitrogen.
reflectance
The percentage of light reflected from a surface.
primary consumers
The second trophic level called the ____ includes the herbivorous animals that eat the plants. Only 10% of the energy from the producers makes it to the primary consumers.
secondary consumers
The third trophic level called the _____ includes carnivores that feed on herbivores. Only 10% of the energy from the primary consumers goes to the secondary consumers.
Why do Inuits have darker skin tone than would be predicted based on their latitude?
Their skin tone developed elsewhere and they migrated more recently, and they have high vitamin D in their diet. There is a boatload of vitamin D in fish oil. The selective pressure for lighter skin exerted by metabolic requirements of vitamin D is lower, because they still get plenty regardless of their melanin level.
Why are starfish considered a keystone species?
They are one of the few organisms that can eat muscles; without them, they grow out of control and outcompete other species.
True or False: The rate of change (∆N/∆t) of a population experiencing exponential growth always increases with increasing population size.
True: exponential growth always grows faster and faster. It is logistic growth that has limits.
umbrella species
Umbrella species are species selected for making conservation-related decisions, typically because protecting these species indirectly protects the many other species that make up the ecological community of its habitat.
16. How is vitamin D linked to natural selection? 17. Which skin tone is linked to higher vitamin D? 18. Based on this information, revised your previous hypothesis to explain the evolution of the variation and distribution of skin color.
Vitamin D is important for bone growth, maintaining calcium and phosphate levels in the body, performs a function for the immune system, and affects mental health. Lighter skin tone allows more vitamin D to be absorbed.
Why hasn't the human population hit it's carrying capacity?
We keep increasing the carrying capacity with technological advances.
trophic cascade
When a change in one species in a community affects species in other trophic levels.
why is the gulf of mexico dead-zone seasonal?
When snow melts there is higher freshwater flow (containing nitrogenous and phosphate fertilizers from farming) into the ocean, and that takes the fertilizer from the rivers down to the gulf.
How did the reintroduction of wolves in yellowstone park affect the aspen tree?
When the wolves were not present in the park, the population of trees declined dramatically, because wolves kept the elk population down. Elk eat aspen saplings. The removal of moves don't effect just Elk; it effets Aspen trees, beetles... and more.
density dependent factor
When things get more crowded, something that stops the population from growing as fast (available of water, available of space, contagious disease) that make carrying capacity what it is. That is the density dependent factor.
What causes the zigzag pattern of CO₂ concentration?
Winter, less PHS, Summer more photosynthesis The northern hemisphere drives it because there is more landmass, therefore more plants
6. Does this figure support the hypothesis you made in question #5? (lattitude vs skin reflectance)
Yes (lattitude vs. skin reflectance)
In order to keep both the fish and the fisherman happy, you want to maximize the number of snapper you can catch without putting the population in jeopardy. What do you do?
You could aim to catch them after their highest spawning potential, by setting a minimum size requirement. But catching only old ones hurts them; they are 11x more productive than young fish. Instead, we set quotas on various sizes of fish; only allowing so many of each size category to be caught by commercial fishers. They also limit the season.
cohort life table
You find bears when they are newborn, and you follow them throughout their entire lives and keep track of their characteristics until none remain. This is a cohort life study. Of the two types of life tables, this gives us the best information but is sometimes impractical
vertical life table
You take a cross section of the entire population, measuring all age groups at once instead of following one group of individuals through their entire life. You sample individuals of all age classes, and only once. From that information, you make inferences about the population.
Shannon's diversity index
a metric based on the probability of correctly identifying the next species based on the current species examined. High H = low diversity, low H = high diversity
mark recapture
a portion of the population is captured, marked, and released. Later, another portion is captured and the number of marked individuals within the sample is counted.
biodiversity hotspot
a region of the world that contains unusually large concentrations of species.
symbiosis
a relationship that occurs when two distinct organisms live in close association with one another
ecosystem engineers
a special type of keystone species, because they physically changed the community in some way. Bears take resources from fresh water ecosystems and transfer them onto land. Without them, that extra energy would not be brought into the community. Beavers are another example; building dams, changing the ecosystem they live in which influences the community.
mimicry
a species adapting to look like another species as a means of protection
non-native/exotic
a species not originally found in a location (i.e. cherry tree)
keystone species
a species that exerts an influence on a community disproportionate to its abundance
transects
a straight line or narrow section through an object or natural feature or across the earth's surface, along which observations are made or measurements taken.
mutualism
a symbiotic relationship in which both participants experience a benefit
parasitism
a symbiotic relationship in which one organism benefits while causing harm to the other organism
commensalism
a symbiotic relationship in which one participant experiences a benefit and the other is unaffected
density independent factor
abiotic conditions that dictate amount (human impact, weather, natural disasters)
population
all the individuals in a given species that live and reproduce in a particular place. key features of a population are size, range, and density
aggregated dispersion
also known as clustered dispersion, individuals are grouped into clusters together within an area
locally extinct
at one location, that organism is no longer found
what are the 4 compartments of physical environment?
atmosphere, fresh waters, oceans, land
per-capita growth rate
average individual contribution to total population growth rate r = (dN/dT)/N₀
fecundity
average number of offspring per a female in the population
quadrats
a₂ quadrat is a plot used in ecology and geography to isolate a standard unit of area for study of the distribution of an item over a large area. While originally rectangular, modern quadrats can be rectangular, circular, or irregular.
conservation triage
can no longer afford to try to protect as many animals and plants as they have in the past, so they are increasingly turning to new systems of triage to explicitly determine which species to save and which to leave to die
ecosystem goods example
coconut; take it and use it. lumber; materials for housing
co-evolutionary arms race
coevolution due to antagonistic species interaction
species interaction
competition -/- predation, herbivory, parasitism, disease +/- mutualism +/+ commensalism +/0
biotic potential
dN/dT = rN growth rate at any given point
herbivory
exploitive relationship; an animals east a plant or algae, does not kill the plant; ANIMAL EATS PLANT
mass extinction and background rate of exintction
for mammals, 1 species every 200 years. currently higher for amphibians, 25k-45k* background rate.
community
group of species interacting with each other in an area
what is the largest threat to endangered species?
habitat loss and degradation
competition
harms both (cheetahs and lions)
species evenness
how close in #s each species are distributed in the community
anthropogenic
human activities such as industry, transportation, mining, and agriculture
exploitation competition
if one species uses the resources, the other species can't
demographics
information about the size, structure, and distribution of a population
indirect interactions
interactions that require paths of length more than one; increase exponentially with species diversity
enemy release hypothesis
invasive species are not held in check b the predators and agents of disease that have always been in place for the natives
species diversity
is a measure of the diversity within an ecological community that incorporates both species richness and the evenness of species' abundances
albedo
is the fraction of solar energy reflected from the Earth back into space
what is the trade-off for phenol as a secondary plant compound?
less herbivory, more likely to freeze
why are prey adaptations so extreme?
lots of selective pressure to avoid being eaten
obligate mutalism
mandatory mutualism; at least one species requires the other for survival
flux
movement of elements/energy/materials between compartments of the biogeochemical cycle
niche
multidimensional habitat that allows a species to practice its way of life. It is determined by biotic and abiotic factors
positive and negative feedback
negative feedback "stop" positive feedback "do this" negative feedback: clouds forming from water vapor cool positive feedback: heating creates water vapor which is a greenhouse gas that speeds up warming
invasive species
nonnative species that overcrowd native species a non-native/exotic species that 120 billion in damage per year. Kudzu, Zebra Mussels; to generate energy, you need a lot of water, but the mussels clog intake tubes
obligate versus facultative mutualism
obligate means at least one requires the other for survival; facultative mutualists improve each other's fitness, but presence is not required
interference competition
one species blocks access to the resource for others
biogeochemical cycle
pattern of movement of a chemical element through living organisms and the 4 compartments of the physical envrionment
phenological mismatch
phenology is timing; timing mismatch. It happens when one organism is using a different queue than the other, and one queue changes (i.e. temperature of weather) and the other remains the same (i.e. daylength)
population vs. community vs. ecosystem
population: interactions, same species community: interactions, multiple species ecosystem: biotic (community) + abiotic interactions
list adaptations you might expect to see in each type of organism: predator, prey, parasite, host, herbivore, plant
predator- speed, claws/teeth, stealth, front-facing eyes prey- speed, stealth, eyes on the side, chemical defense, aposematism, mimicry, crypsis, parasite- hooks, thick cuticle, strong jaws host- immune response to parasites herbivore- flat grinding teeth plant- poisonous secondary plant compounds
survivorship (life table)
proportion of the original group that are still alive (the proportion of the original cohort who survive to age X.)
facultative mutualism
species has higher fitness when the other is present, but presence is not require
predation
the act of one organism (predator) feeding on another organism (prey)
evapotranspiration ratio
the balance between potential evaporation - how hot it is - and potential transpiration - how much water (rainfall) there is available for the plants to transpire. The larger the ratio, the shorter of water the plant is likely to be.
biome
the distinctive and stable assemblage of species found over a broad region of earth. Terrestrial biomes are classifield by precipitation and temperature patterns.
carrying capacity
the maximum number of organisms that can exist in an ecosystem given the available resources
what portion of the an exponential growth graph is growing the fastest?
the midpoint
nitrogen cycle
the process by which atomospheric nitrogen is made available for organisms and eventually returned to the atmosphere
cospeciation
the process in which a speciation event in one organism causes speciation in a linked organism
coevolution
the process in which two species evolve in response to each other
mortality (life table)
the proportion of each age class that dies before reaching the next age class (the proportion of individuals of age X who die before reaching age X+1.) 65 in 4-5 age class:, 62 in the next. 3 die. Mortaility = 3/65
niche dimension
the scope of a single dimension of the ecological role performed by a species
why do we care about saving biodiversity?
use value (direct/indirect) option value existance value
hypoxia
very low oxygen concentration
aposematism
warning coloration; predators learn that it tastes bad or makes them sick. Some species can take advantage of that through mimicry.
competitive exclusion
when one species prevents another from occupying a particular habitat
environmental resistance
when the biological growth gets close to the carrying capacity, it slows down the growth.