Exam 3

Which group is not a population?

All four groups are populations, because they are all individuals of certain species living within a given area.

Activity: Write a Figure Legend

Bluegills prefer certain water temp; when given a choice between 27 degrees celsius and 31 degrees celsius, bluegills spent a majority of their time at 31 degrees celsius.

Equation

Change in population size per time = Per Capita Growth Rate * Current Population Size READ THIS PART OF TEXTBOOK

A climate-envelope model estimates the fundamental niche of a species.

False

A realized niche is usually larger than a fundamental niche.

False

A tragedy of the commons occurs when individuals cooperate to manage a shared resource effectively.

False

Carbon dioxide emitted by human activities will remain in the atmosphere unless humans design technologies to remove this compound from the air.

False

Carbon is found only in plants in animals.

False

Cheating confers the smallest benefit when most members of the group cooperate.

False

Diffuse coevolution occurs when one species of plant coevolves with one species of pollinator.

False

Positive feedback occurs when warming caused by carbon emissions leads to a higher rate photosynthesis.

False

The greatest density of species occurs at the North Pole.

False

The larger the competitive effect on a species (alpha or beta), the more likely the species will persist during competition.

False

The model of competition between species can ignore competition within species.

False

The rate of population growth (r) determines whether a species can persist during competition.

False

True or False? Competing species are more likely to coexist if their growth rates (r1 and r2) increase.

False; R1 and R2 actually don't have an effect on whether species coexist, instead, they change the rate at which the population grows, towards it's carrying capacity; it doesn't have any effect on whether two species coexist, only how quickly those species can grow when their populations are small; K1 and K2, as well as alpha and beta, have a larger effect.

True or False? A climate-envelope model uses a fundamental niche to predict the distribution of a species.

False; a climate-envelope model uses a realized niche.

True or False? Sampling quadrats would be the better method for estimating the number of whales in a population.

False; by putting down little sub-samples and counting how many whales are in there, those whales could leave and swim somewhere else so that when you put a quadrant down somewhere else, that same whale might have come up again as they are mobile organisms. Therefore, mark and recapture would be a better method for estimating the number of whales in a population.

True or False? When teammates could not punish, cheating was an irrational choice by players.

False; cheating is a rational or logical choice when no one is going to punish you.

True or False? Dan Janzen proposed that speciation occurs more often in the tropics because tropical species mutate faster.

False; he did not mention faster rates of mutation; he did mention that there is far more variation in climate in high latitudes than there are in the tropics.

True or False? If Daphnia magna adapted to warming, any species of fish in these ponds likely adapted as well.

False; just because one population can adapt to a changing environment, doesn't necessarily mean that any population can.

True or False? A pair of species engaged in comensalism can coevolve.

False; only one member receives a benefit.

True or False? If productivity enhances diversity, one should see more species in deep tropical waters than along shallow coastlines.

False; so if productivity enhances diversity, one should see more species along shallow coastlines; even though we're not seeing that, that's what we would predict if it was all about productivity.

True or False? Paramecium are most likely to persist at intermediate temperatures?

False; the competitive effect is going to be largest and at intermediate temps, paramecium will likely go extinct; it will likely persist at high and low temps

True or False? When cane toads are added to a community, the number of crimson finches should decrease.

False; the number of crimson finches should increase and benefit from the introduction of cane toads as they have a negative affects on those eating them, meaning that they are not preying on as many crimson finches as they use to.

True or False? The phenotypic difference between the two sets of populations could have resulted from plasticity instead of evolution.

False; trying to eliminate plasticity as they're removing any chance that a difference between the two sets of populations would be caused by the environment that they grew up in, because they're growing up all these populations in the same lab environment.

True or False? Mark and recapture would be the better method for estimating the number of saguaros in a population.

False; unnecessary because these plants don't move. Sampling would be a better method for non-mobile organisms.

True or False? Cheating confers the smallest benefit when most members of the group cooperate to invest.

False; when most members of the group cooperate to invest, cheating confers a large benefit.

What factors determine whether a species can adapt to environmental change?

Generation time, mutation rate, recombination, niche width, net immigration, population size, rate of warming.

How can we promote cooperation on a large scale?

Incentives or punishment.

How might rising CO2 impact an ecosystem?

Increase photosynthesis, carbonic acid decrease populations in the sea, indirectly increase herbivore density, therefore increase carnivore density.

How could you estimate the population of whales?

Mark and recapture or sampling quadrats

What is the appropriate control in this experiment?

Ponds that circulate water (at the same rate) as well, but don't heat it.

What is coevolution?

Reciprocal evolution between two or more species.

What determines the productivity of a community?

Sunlight, water, trace elements (nitrogen) and minerals that plants can collect from the ground.

Why do bluegulls nest on the edge of the lake?

The habitat in the shallow water might receive more solar radiation, holds more zooplankton (which is what they eat), more protective over young than it in deeper water where larger fish reside, more algae for the fish to hide in, warmer water for embryos to develop quickly and enhance survival/fitness.

Which of the following observations most strongly supports the hypothesis that ants and Acacia trees have experienced one-on-one coevolution?

The removal of either trees or ants from the environment causes extinction of the remaining species.

How can several species of dung beetles coexist?

There has to be something about their niches that differ; if they both eat dung, it can't be what they eat, but there has to be something else that keeps them from out-competing one another; there has to be some other resource that's limiting the one species from getting all the dung.

Which of the following limitations of climate envelope models was not discussed in the video?

They ignore abiotic factors such as temperature.

How might cane toads change communities?

Things that they could eat would decrease in frequency and perhaps go extinct; predators that are feeding on cane toads are going to be negatively affected themselves by either dying or being drugged out to the point where a larger predator eats them; or if they taste a toad they don't like, they learn to ignore all other kinds of toads.

A teleconnection occurs when carbon dioxide from western Europe enters the Indian Ocean and reacts to form an acid.

True

An indirect effect must involve at least three species.

True

Coevolution has important consequences for medicine, because pathogens coevolve with their hosts.

True

Coevolution is the reciprocal evolution of two or more species.

True

If the remaining fossilized carbon were combusted the rise in atmospheric carbon dioxide would exceed the rise observed since 1900.

True

If two species compete, neither species will reach its carrying capacity before one of the species goes extinct.

True

Positive feedback occurs when warming caused by carbon emissions leads to higher rates of microbial respiration and decomposition.

True

Punishment promotes cooperation by creating a cost that balances the benefit of selfishness.

True

True or False? The carrying capacity of a population depends on the resources available in the environment.

True

When people cannot punish cheaters, cheating becomes a rational choice.

True

When two species have different niches, the competition coefficients (alpha and beta) are likely to be less than 1.0.

True

True or False? A more specialized species should occur over a narrower range of altitudes.

True; a specialist can only handle the small range of conditions and altitudes as the higher you move, the colder it gets, and the lower you go, the hotter it gets.

True or False? To test the hypothesis that greenhouse gases cause global warming, we need to replicate the observations of warming on Earth by studying multiple planets.

True; experiments need to be manipulated although it won't be at the scale of the Earth.

True or False? If males compete for space, a large male will likely force a small male to spend less time on the side of the tank with the optimal temperature.

True; if males compete for space, large males will force small males out.

True or False? If species of beetles have the same niche, eventually all but one species will become extinct.

True; if they had the same niche, eventually one of them would out-compete the others and they would go extinct; even if they were identical in their ability to compete by chance, one of them would go extinct.

True or False? The shrinking population between 1965 and 1970 could have resulted from a decrease in the birth rate or an increase in the death rate.

True; it "could" be either of these.

True or False? The growing population between 1985 and 1995 could have resulted from a decrease emigration or an increase in immigration.

True; it could be either of these.

True or False? When two variables are correlated, an increase in one variable does not necessarily cause an increase in the other variable.

True; it does not necessarily mean cause and effect.

True or False? Greater productivity could support more individuals of a species without supporting more species.

True; just because you have this huge amount of primary productivity doesn't mean that what it's gonna give you is more species; productivity will mean that you can have more organisms in a place, but it doesn't guarantee you having more species in a place; the difference between more and diverse is important; when you have a lot of productivity, all you get is more gray squirrels and more blue jays, but you don't get lots of different birds and lots of different squirrels, or lots of different mammals and rodents.

True or False? If species compete for many generations, natural selection would cause their niches to diverge.

True; natural selection can select for variance (mutations) that separate them and reduce competition.

True or False? More solar radiation and more precipitation would likely result in more energy for carnivores.

True; plants absorb the solar radiation, using it to make energy, carbohydrates from photosynthesis; then herbivores can eat those plants and the energy can get up to the herbivores; if there is more solar radiation, there could be more plant growth, and if there's more plant growth, there could be more herbivores eating the plant tissue; if there are more herbivores, then the carnivores will have more food and more energy.

True or False? To promote cooperation, it's easier to threaten punishment than to promise reward.

True; promising a reward is a cost.

True or False? The native range of pythons likely excludes areas in which freezing temperatures occur during winter.

True; species from the tropical parts of Asia, which is not seen in the native range of the realized niche of the python.

True or False? A cane toad is a keystone species in this Australian community.

True; yet has a negative impact on a diversity of a community.

The atmosphere is changing because ___________________________.

carbon is being added faster than it is removed

Which approach do biologists use most commonly to predict how species will respond to climate change?

climate envelope models

The diagram above shows a food web in which arrows point from predators to their prey. Based on this diagram, you can confidently conclude that increasing the density of species A will

decrease the density of species B.

Which organisms could be affected by climate change?

domestic animals reared for food, insects and bacteria that cause disease, plants and fungi used to make medicines, large animals that attract tourists

The human population has grown ____________________

exponentially.

Humans influence the carbon cycle by ____________________________.

mining carbon-based materials that were buried over millions of years, combusting carbon-based fuels to generate power, planting trees to generate timber for the building industry

Tropical species are __________________________

most at risk from climate change because tropical species likely have narrow niches.

Species in the tropics should have __________________________

narrow niches because they experience stable conditions.

Carbon dioxide enters the atmosphere when ______________________.

plants burn in a wildfire, organisms respire, organisms decompose.

A population stops growing when it _____________________

reaches its carrying capacity.

A keystone species ___________________________.

strongly affects the structure of a community

Which of the following scenarios describes an indirect effect?

the abundance of plants increases when predators limit herbivores.

The growth of a population depends on __________________

the birth rate minus the death rate.

Dan Janzen argued that tropical communities contain more species because __________________________

tropical environments favor specialized niches, which limits gene flow and promotes speciation.