question

What causes skin cancer?

answer

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.

question

Why are Caucasians more at risk?

answer

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.

question

What age does skin cancer typically occur?

answer

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.

question

Why is light skin favored at high altitudes?

answer

1) Vitamin D provision 2) Thermo-regulation

question

Why is dark skin favored at low altitudes?

answer

1) Folate Levels, 2) Thermo-regulation, 3) Immuno-regulation, 4) Effective foraging and hunting, 5) Skin permeability, 6) Skin cancer protectant

question

HAR1

answer

Human Accelerated Region: highly changed region between humans and chimps, most dramatic is HAR1

question

How do they identify human accelerated regions?

answer

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.

question

4. Does the amount of UV light reaching the Earth vary in a predictable manner? If so, describe the pattern you observe.

answer

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.

question

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.

answer

The most darkly pigmented would be in equatorial Africa, The most lightly pigmented would be in the highest region

question

6. Does this figure support the hypothesis you made in question #5? (lattitude vs skin reflectance)

answer

Yes (lattitude vs. skin reflectance)

question

reflectance

answer

The percentage of light reflected from a surface.

question

transmittance

answer

A measure of the fraction of light that passes through a sample

question

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?

answer

Skin cancer, Sun burns, Vitamin D

question

In order for a trait to evolve through natural selection, the trait must help ...

answer

... some individuals survive and reproduce better than others

question

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?

answer

Not that strong; it commonly occurs later in life after individuals have already reproduced and passed on their genes.

question

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?

answer

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.

question

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?

answer

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.

question

13. All other things being equal, which skin tone would you expect to be correlated with higher levels of folate?

answer

Darker skin would have more Melanin and thus, less transmittance of UV light.

question

14. What would happen to the reproductive success of:

answer

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)

question

15. Can folate alone explain the variation and distribution of light/dark skinned individuals around the world?

answer

No. Higher melanin isn't ideal for vitamin D production and thermoregulation at higher altitudes.

question

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.

answer

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.

question

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

answer

A. higher, B. higher, C. higher, D. higher

question

20. Predict the skin tones expected at different latitudes, taking ONLY vitamin D needs into consideration.

answer

If only vitamin D needs to be taken into consideration, there would be light skin everywhere but especially at the poles.

question

Why do Inuits have darker skin tone than would be predicted based on their latitude?

answer

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.

question

Why do we care about population ecology?

answer

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

question

population

answer

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

question

transects

answer

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.

question

quadrats

answer

a? 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.

question

mark recapture

answer

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.

question

random dispersion

answer

Individuals are equally likely to occur in any spot in an area

question

uniform dispersion

answer

Individuals spaced evenly in an area

question

aggregated dispersion

answer

also known as clustered dispersion, individuals are grouped into clusters together within an area

question

per-capita growth rate

answer

average individual contribution to total population growth rate r = (dN/dT)/N?

question

growth rate

answer

r = dN/dT

question

biotic potential

answer

dN/dT = rN growth rate at any given point

question

carrying capacity

answer

the maximum number of organisms that can exist in an ecosystem given the available resources

question

what portion of the an exponential growth graph is growing the fastest?

answer

the midpoint

question

environmental resistance

answer

when the biological growth gets close to the carrying capacity, it slows down the growth.

question

logistic growth

answer

N = Pop size N? = Pop size @ year 1 r = per-capita growth rate t = time K = carrying capacity *growth stops when N = K

question

Why hasn't the human population hit it's carrying capacity?

answer

We keep increasing the carrying capacity with technological advances.

question

True or False: The rate of change (?N/?t) of a population experiencing exponential growth always increases with increasing population size.

answer

True: exponential growth always grows faster and faster. It is logistic growth that has limits.

question

If you were a scientist studying grizzly bears in a wild, rugged mountain ecosystem, how would you count them?

answer

Tag them with radioactive darts. Thermal imaging at night in quartets. Motion sensitive cameras Tranquilizer darts. GPS collars / radio collars

question

DNA Mark Recapture

answer

-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...

question

density dependent factor

answer

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.

question

density independent factor

answer

abiotic conditions that dictate amount (human impact, weather, natural disasters)

question

demographics

answer

information about the size, structure, and distribution of a population

question

survivorship (life table)

answer

proportion of the original group that are still alive (the proportion of the original cohort who survive to age X.)

question

mortality (life table)

answer

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

question

fecundity

answer

average number of offspring per a female in the population

question

cohort life table

answer

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

question

vertical life table

answer

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.

question

Why does survivorship always trend downwards for a life cohort table?

answer

It's the proportion of the original.

question

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?

answer

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.

question

If there are a lot of young people as a percentage of the population, what does that tell you?

answer

That the population is growing quicker than a population with a more even spread.

question

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.

answer

1 large, 2 many, 3 a lot of, 4 relatively low, 5 late maturation rate, 6 K

question

K strategy versus r strategy

answer

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.

question

survivorship curves, K vs. R

answer

K: 1 or II r: III

question

metapopulation

answer

Population subdivided into several small and isolated populations due to habitat fragmentation.

question

How do you determine if you have a metapopulation, as opposed to multiple closed populations or one contiguous population?

answer

If there is gene flow but the growth rates of the subdivided populations are different, than you have a metapopulation.

question

Metapopulation of Sinai baton blue butterflies: make a list of questions / biological information that would assist in conversation.

answer

*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

question

locally extinct

answer

at one location, that organism is no longer found

question

rescue effect

answer

extinction events could be masked if the sub-population is re-colonized by a source of the same species

question

trophic cascade

answer

When a change in one species in a community affects species in other trophic levels.

question

community

answer

group of species interacting with each other in an area

question

How did the reintroduction of wolves in yellowstone park affect the aspen tree?

answer

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.

question

keystone species

answer

a species that exerts an influence on a community disproportionate to its abundance

question

Why are starfish considered a keystone species?

answer

They are one of the few organisms that can eat muscles; without them, they grow out of control and outcompete other species.

question

ecosystem engineers

answer

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.

question

biodiversity hotspot

answer

a region of the world that contains unusually large concentrations of species.

question

biome

answer

the distinctive and stable assemblage of species found over a broad region of earth. Terrestrial biomes are classifield by precipitation and temperature patterns.

question

evapotranspiration ratio

answer

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.

question

species interaction

answer

competition -/- predation, herbivory, parasitism, disease +/- mutualism +/+ commensalism +/0

question

mutualism

answer

a symbiotic relationship in which both participants experience a benefit

question

competition

answer

harms both (cheetahs and lions)

question

predation

answer

the act of one organism (predator) feeding on another organism (prey)

question

parasitism

answer

a symbiotic relationship in which one organism benefits while causing harm to the other organism

question

herbivory

answer

exploitive relationship; an animals east a plant or algae, does not kill the plant; ANIMAL EATS PLANT

question

commensalism

answer

a symbiotic relationship in which one participant experiences a benefit and the other is unaffected

question

list adaptations you might expect to see in each type of organism: predator, prey, parasite, host, herbivore, plant

answer

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

question

aposematism

answer

warning coloration; predators learn that it tastes bad or makes them sick. Some species can take advantage of that through mimicry.

question

mimicry

answer

a species adapting to look like another species as a means of protection

question

why are prey adaptations so extreme?

answer

lots of selective pressure to avoid being eaten

question

symbiosis

answer

a relationship that occurs when two distinct organisms live in close association with one another

question

niche

answer

multidimensional habitat that allows a species to practice its way of life. It is determined by biotic and abiotic factors

question

niche dimension

answer

the scope of a single dimension of the ecological role performed by a species

question

competitive exclusion

answer

when one species prevents another from occupying a particular habitat

question

interspecific competition

answer

Competition between individuals of different species

question

exploitation competition

answer

if one species uses the resources, the other species can't

question

interference competition

answer

one species blocks access to the resource for others

question

obligate mutalism

answer

mandatory mutualism; at least one species requires the other for survival

question

facultative mutualism

answer

species has higher fitness when the other is present, but presence is not require

question

obligate versus facultative mutualism

answer

obligate means at least one requires the other for survival; facultative mutualists improve each other's fitness, but presence is not required

question

indirect interactions

answer

interactions that require paths of length more than one; increase exponentially with species diversity

question

primary producers

answer

autotrophs

question

primary consumers

answer

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.

question

secondary consumers

answer

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.

question

coevolution

answer

the process in which two species evolve in response to each other

question

cospeciation

answer

the process in which a speciation event in one organism causes speciation in a linked organism

question

co-evolutionary arms race

answer

coevolution due to antagonistic species interaction

question

Why won't you see coevolution in commensalism?

answer

+/0 : one species is not effected by the other

question

species richness

answer

Number of species in a community.

question

species evenness

answer

how close in #s each species are distributed in the community

question

species diversity

answer

is a measure of the diversity within an ecological community that incorporates both species richness and the evenness of species' abundances

question

Shannon's diversity index

answer

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

question

population vs. community vs. ecosystem

answer

population: interactions, same species community: interactions, multiple species ecosystem: biotic (community) + abiotic interactions

question

biogeochemical cycle

answer

pattern of movement of a chemical element through living organisms and the 4 compartments of the physical envrionment

question

what are the 4 compartments of physical environment?

answer

atmosphere, fresh waters, oceans, land

question

flux

answer

movement of elements/energy/materials between compartments of the biogeochemical cycle

question

photosynthesis and respiration

answer

6CO? + 6H?O ? C?H??O? + 6O?

question

What is the biggest carbon reservoir?

answer

Most are buried deep below the earth's surface.

question

Why does burning fossil fuels release CO2?

answer

Fossil fuels are composed of organic material; old plants and algae.. CH? + 2O? ?CO? + 2H?O

question

Describe 2 ways in which deforestation leads to increases in CO2 in the ATM

answer

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 CO?

question

What causes the zigzag pattern of CO? concentration?

answer

Winter, less PHS, Summer more photosynthesis The northern hemisphere drives it because there is more landmass, therefore more plants

question

troposphere

answer

First layer of atmosphere, 0-10 miles above Earth's surface. Contains weather, greenhouse gases, and bad ozone

question

greenhouse gases

answer

Most significant:H?O, CO?, CH?, CFC's. Trap outgoing infrared energy in the troposphere causing the earth to warm.

question

anthropogenic

answer

human activities such as industry, transportation, mining, and agriculture

question

positive and negative feedback

answer

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

question

albedo

answer

is the fraction of solar energy reflected from the Earth back into space

question

permafrost

answer

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

question

what is the trade-off for phenol as a secondary plant compound?

answer

less herbivory, more likely to freeze

question

What cues do organisms use to time important events?

answer

Temperature, daylength, moon.

question

umbrella species

answer

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.

question

evolution first

answer

Evolution-first approaches seek to preserve genetic diversity, which can help all the world's species survive and adapt in fast-changing environmental conditions

question

function first

answer

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.

question

conservation triage

answer

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

question

if bird's use day length as a cue for major life event,s you would expect that earlier warm spring weather would:

answer

NOT change the date of laying

question

phenological mismatch

answer

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)

question

The ocean absorb between 25-40% all man-made carbon dioxide. Do you think this is good or bad for biodiversity?

answer

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

question

nitrogen cycle

answer

the process by which atomospheric nitrogen is made available for organisms and eventually returned to the atmosphere

question

eutrophication

answer

Enrichment of water by inorganic nutrients used by phytoplankton. Often, overenrichment caused by human activities leads to excessive bacterial growth and oxygen depletion.

question

algal bloom

answer

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.

question

hypoxia

answer

very low oxygen concentration

question

why is the gulf of mexico dead-zone seasonal?

answer

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.

question

ecosystem goods example

answer

coconut; take it and use it. lumber; materials for housing

question

ecosystem services

answer

Our planets ecological systems that purify air and water, cycle nutrients, regulate climate, regulate climate, pollinate plants, and recycle our waste.

question

why do we care about saving biodiversity?

answer

use value (direct/indirect) option value existance value

question

indicator species

answer

Species that serve as early warnings that an ecosystem is being damaged. "canaries in the coal mine"

question

what is the largest threat to endangered species?

answer

habitat loss and degradation

question

mass extinction and background rate of exintction

answer

for mammals, 1 species every 200 years. currently higher for amphibians, 25k-45k* background rate.

question

non-native/exotic

answer

a species not originally found in a location (i.e. cherry tree)

question

invasive species

answer

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

question

characteristics of zebra mussel questions, in class worksheet last week

answer

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)

question

Which do you like better out of evolution first, function first, or hotspot first, and why?

answer

Function first; more efficient use of resources.

question

enemy release hypothesis

answer

invasive species are not held in check b the predators and agents of disease that have always been in place for the natives

question

each potential solution

answer

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,

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