Deck 16: Ecology

Question 1

Why are Kirkland's warblers particularly vulnerable to human development?

A) They're extremely sensitive to any disturbance in their habitat.
B) They require young jack pine trees, which tend not to grow where humans live and suppress forest fires.
C) They follow cattle and bison around and eat insects they stir up, and bison are rare near human developments.
D) They require tall jack pine trees, which take a long time to grow and humans tend to remove when they develop an area.
E) They will only nest in recently burned areas and people suppress fire when they move into an area.

Answer 1

B

Question 2

Why are cowbirds a particular problem for Kirkland's warblers?

A) The cowbirds have only recently started parasitizing the warbler nests, so they haven't had time to adapt yet, and the warblers are rare to start with.
B) The cowbirds bring bison into warbler territory, and they tend to trample the warbler nests because they're on the ground.
C) Cowbird eggs look a lot like warbler eggs, so the warblers don't recognize they aren't their own.
D) Warblers and cowbirds prefer the same sort of habitat.
E) Kirkland's warblers tend to get stuck in traps designed for the cowbirds.

Answer 2

A

Question 3

Physiologically, how does a kangaroo rat conserve water?

A) They drink more than most animals.
B) Their liver is highly efficient at saving water.
C) Their kidneys are highly efficient at eliminating waste without losing much water.
D) They are highly efficient at extracting water from their food.
E) They don't urinate and their feces are very dry.

Answer 3

C

Question 4

How does staying underground in a burrow during the day help a kangaroo rat conserve water?

A) They're safer from predators and can go out and drink at night.
B) It's too hot in a desert for any mammal to be out during the day at all.
C) The food absorbs moisture from the ground and the rats get extra water that way.
D) Their exhalation in the burrow keeps the humidity high, the food absorbs that water, and they thereby recycle some of the water they lose through respiration
E) Because they each have their own "territory" in a burrow, they don't have to compete for water there.

Question 5

Why do yellow-bellied marmot females live two to five per den? Wouldn't it be better for them to each have their own den?

A) One den per female might be better, but there aren't enough dens to go around.
B) One female can't care for a litter of offspring by herself, so they have to live together and cooperate.
C) One male can mate with two to five females, so he will work to defend one den for that many.
D) The only way a female can defend a den from predators is if she has help.
E) There are more females than males, so this is the only way everyone gets to mate.

Question 6

White-fronted bee eaters are birds that mature at about one year of age but often stay with their parents to help raise the next brood of siblings even though they could be raising their own offspring. Why would they do this?

A) The parents can't successfully raise a nest of offspring without help.
B) The young birds need a year of practice before they can successfully raise their own offspring.
C) There aren't enough mates to go around every year and only more mature birds can attract mates.
D) There aren't enough nesting sites for everyone every year, and more mature birds are better at defending territory.
E) There is no explanation for this.

Question 7

Which of the following best describes a predator-prey relationship?

A) Competition
B) Mutualism
C) Cooperation
D) Altruism
E) Exploitation

Question 8

For competition between species to occur, which of the following is required?

A) They have different niches.
B) The resources they both need are limited.
C) They're together in the same place at the same time.
D) One eats the other.
E) They're on the same trophic level.

Question 9

According to Gause, two species that use the same resource do fine when they exist separately, but one outcompetes the other when they're together. What does this illustrate?

A) Mutualism
B) Competition
C) The life-dinner principle
D) The competitive exclusion principle
E) Murphy's law

Question 10

If two species share similar niches, can they coexist?

A) No. The competitive exclusion principle says one will die off.
B) No. One will always outcompete the other.
C) Yes. In nature there is always enough to go around.
D) Yes. As long they're using at least a few different resources.
E) There is no way to predict. You'd have to research them.

Question 11

With the 14 species of Galapagos finches, what one key adaptation allowed them to share resources and not outcompete each other?

A) Changes in beak size allowed them to each use a different food resource.
B) Changes in wing size altered flight speed so they could get away from each other.
C) It wasn't so much an adaptation as Charles Darwin moving each species to a separate island.
D) Whenever a population dies off on one island, replacements move in from another so no one ever truly goes extinct.
E) They migrate whenever competition gets too stiff.

Question 12

Clownfish live inside anemones. The clownfish get protection and the anemone eats scraps from clownfish meals. This is an example of which of the following?

A) Competitive exclusion
B) Mutualism
C) Exploitation
D) Competition
E) A unique interaction among very different species

Question 13

Parasitism is an example of what type of interaction?

A) Mutualism
B) Predation
C) Competition
D) Cooperation
E) Exploitation

Question 14

What is an example of a population cycle?

A) Parasitism, like with the Kirkland's warblers and the cowbirds
B) Competition, like with monarch butterflies and milkweed
C) Character displacement, like with the Galapagos finches
D) Exploitation, like with the lynx and snowshoe hares
E) Adaptation, like with the white-fronted bee eaters

Question 15

Milkweed produces toxins to deter herbivores, but monarch caterpillars have adapted to be resistant and actually use the toxins to deter their own predators. What is this an example of?

A) Exploitation
B) An evolutionary arms race
C) Competition
D) A population cycle
E) The competitive exclusion principle

Question 16

European cuckoos lay their eggs in the nests of other birds. Different cuckoos specialize in parasitizing different species' nests, and their eggs mimic those eggs. This is an example of what?

A) Coevolution
B) The competitive exclusion principle
C) Character displacement
D) Mutualism
E) A population cycle

Question 17

Cowbird eggs don't look much like Kirkland's warbler eggs, but the warblers don't discriminate, so don't kick the foreign eggs out. Why not?

A) Warblers aren't that smart.
B) Warblers, like most birds, can't see too well.
C) Cowbirds only recently invaded the warbler territory and the warblers probably haven't had time to adapt yet.
D) Cowbirds are so rare that this doesn't happen enough for the warblers to have to respond.
E) The competitive exclusion principle doesn't apply to these species.

Question 18

How is pollination an example of mutualism?

A) The plant shares its nectar with the pollinator.
B) The pollinator carries pollen plant to plant, allowing fertilization.
C) The plant gets a pollinator specially adapted to carry its particular pollen.
D) The plant gets pollinated and the pollinator gets food.
E) The pollinator gets food specifically adapted for it.

Question 19

Why is having a pollinator so important for a plant?

A) Plants don't get fertilized any other way.
B) Since plants don't move, it's one of their only ways of dispersing their population and avoiding inbreeding.
C) With one pollinator species per plant species, they can adapt very well to each other.
D) Without pollinators we wouldn't have much food.
E) Without pollinators, plants wouldn't have much food.

Question 20

Different species of fig wasps specialize in pollinating specific species of fig. Their mutualism is obligatory. What is the potential problem with this strategy?

A) There aren't enough species of fig wasps to go around, so not every fig gets pollinated.
B) There aren't enough species of figs to go around, so not every wasp gets food and a place to live.
C) Wasps both eat from and live in the figs, so once one wasp moves in, no further pollination can occur.
D) If "your" wasp, or "your" fig dies out, you die out, too.
E) There is no problem. It's a great strategy.

Question 21

How do some orchids "cheat" in their relationship with their pollinators?

A) They don't always give out nectar, but they still gets pollinated.
B) They don't really need the pollinator to get pollinated.
C) They mimic female bees or wasps and so the male wastes sperm and doesn't get food, but the orchid gets pollinated.
D) They don't always give out pollen to the pollinators.
E) Wasps or bees get mates but the orchid gets nothing.

Question 22

What happens to other species when humans disrupt a habitat?

A) Any other species in the way goes extinct.
B) Sometimes we get the resource and sometimes the species originally present manage to keep it.
C) Most competing species have to go elsewhere if they can, but there are some species that thrive on human landscapes.
D) Most other species do better when humans alter the landscape.
E) There is no way to predict this because it depends what kind of disruption it is.

Question 23

How do we know that some species are very good competitors with humans?

A) They just have big populations like ours.
B) They seem to be everywhere we are.
C) We spend a lot of money trying to eradicate them.
D) They take a lot of our resources.
E) All of the above

Question 24

Which of the following would you consider to be an effective competitor with humans?

A) Certain "weeds"
B) Snakes
C) Tigers
D) The bacteria that cause small pox
E) Dogs

Question 25

Humans are the genus Homo. Is it true that only Homo sapiens have ever existed, or were there other "people" around at some point, with whom we had to compete?

A) It is true that we are the only species in the genus Homo.
B) There have been other "people" in our evolutionary history, but we never existed alongside them so we never competed. We came later.
C) There have been several other species in the genus Homo, but they lived in different places than our Homo sapiens ancestors, so we never competed with them.
D) Early Homo sapiens competed directly with Homo neaderthalensis and won.
E) There's no way to know whether there were ever other "people" on Earth.

Question 26

Humans take advantage of the adaptations of other organisms found in nature. True or False?

A) False. We are best adapted so there's no reason to look to nature for "improvements."
B) False. We are smart enough to figure out how to get what we need. We don't need to depend on adaptations in nature.
C) False. We don't know what kind of adaptations other organisms use.
D) True. Humans have very few adaptations of our own, so we have to depend on other organisms.
E) True. Many of our drugs and spices come from the chemical defenses of other organisms.

Question 27

Pollination is a common mutualism between animals and plants. Do humans have a common mutualism with plants?

A) No. We depend on the mutualisms of the other animals.
B) Yes. We travel so much, we also serve as pollinators of plants, dispersing their pollen worldwide now.
C) No. We just eat plants. They don't get anything from us.
D) Yes. We help plants disperse their seeds via the fruits we love to eat.
E) No. We don't interact that much with plants at all.

Question 28

Why are there fewer lions than there are wildebeests?

A) Lions eat too much.
B) Wildebeests reproduce more quickly.
C) Humans hunt lions but not wildebeests.
D) There is more energy available in the ecosystem for herbivores like wildebeests.
E) Humans eat meat so they compete with the lions for food.

Question 29

Where does the energy in an ecosystem come from initially?

A) All the plants
B) All the organisms
C) The decomposers recycle it
D) The lithosphere
E) The Sun

Question 30

Why are there never more than two to three levels of carnivores in the trophic pyramid of an ecosystem?

A) Carnivores take up a lot of space.
B) Most of the energy in each trophic level is used up before it is passed to the next level so after two to three levels above the herbivores, it's gone.
C) There aren't enough herbivores to support them.
D) The carnivores are very inefficient in their use of energy, so it gets lost.
E) Humans hunt the carnivores.

Question 31

In a trophic pyramid, what is there the most of?

A) Decomposers
B) Primary producers
C) Herbivores
D) Primary carnivores
E) Secondary carnivores

Question 32

How does energy from the sun become a type of energy an animal can use?

A) Respiration
B) Decomposition
C) Photosynthesis
D) Carbon cycle
E) Herbivores

Question 33

There are several biogeochemical cycles that keep ecosystems running smoothly. Which two depend on the same two linked processes?

A) The carbon and oxygen cycles both depend on photosynthesis and respiration.
B) The carbon and nitrogen cycles both depend on photosynthesis and respiration.
C) The nitrogen and oxygen cycles both depend on photosynthesis and respiration.
D) The hydrospheric and atmospheric cycles both depend on evaporation and precipitation.
E) All the cycles work independently of each other.

Question 34

Living organisms use nitrogen to make proteins and DNA, so how does that nitrogen eventually get back to the atmosphere in the nitrogen cycle?

A) Exhalation
B) Denitrifying bacteria producing nitrates
C) Denitrifying bacteria producing N₂
D) Nitrogen is 79% of the atmosphere, so while it does cycle around, the amount living things contribute is negligible.
E) It dissolves in water and then evaporates back to the atmosphere.

Question 35

Genes might be considered something we get from which of the following support services that ecosystems provide?

A) Provisioning services
B) Regulating services
C) Cultural services
D) Supporting services
E) Development services

Question 36

Capture of solar energy might be considered something we get from which of the following support services that ecosystems provide?

A) Provisioning services
B) Regulating services
C) Cultural services
D) Supporting services
E) Development services

Question 37

The aesthetic or recreational value of an ecosystem might be considered something we get from which of the following support services that ecosystems provide?

A) Provisioning services
B) Regulating services
C) Cultural services
D) Supporting services
E) Development services

Question 38

Pollination might be considered something we get from which of the following support services that ecosystems provide?

A) Provisioning services
B) Regulating services
C) Cultural services
D) Supporting services
E) Development services

Question 39

Honey bee populations seem to be declining worldwide. Without bees, what would we have to do differently?

A) We wouldn't have to pay for insecticides to kill bees.
B) Without pollination by bees for free, we'd either have no fruit, or we'd have to pay for some other way to pollinate plants.
C) We would have to give up eating fruits.
D) Some other insects would take over pollination so we wouldn't do anything differently.
E) There's no way to predict what would happen without bees in the world.

Question 40

We add nitrogen to the soil to enhance plant growth and increase our food supply. What is the downside of this?

A) Nothing. We need the food and the nitrogen enhances production.
B) It's a waste of money because the added nitrogen doesn't make much difference in plant production.
C) It's a waste of money because the soil bacteria supply all the nitrogen the plants can possibly use.
D) It does increase plant production, but the excess ends up in our water, promoting algae growth and making the water undrinkable and, at times, unlivable for fish.
E) Nothing because the excess nitrogen just evaporates into the atmosphere as part of the nitrogen cycle.

Question 41

Luckily, biogeochemical cycles on Earth are too big and complex for anything humans do to impact them. True or False?

A) False. For example, we've added carbon dioxide to the atmosphere, and it is changing our climate.
B) True. The earth processes cycle on in natural patterns, regardless of what we do.
C) False. Everything we do impacts biogeochemical cycles.
D) True. Humans haven't been around long enough to have an impact.
E) False. We do impact them, but they always bounce right back to normal.
"Biology in Perspective"

Question 42

Why should we care about the services that intact ecosystems provide?

A) We shouldn't, really. We don't impact them.
B) We shouldn't really. We impact them but they keep doing what they do.
C) Because our survival depends on those ecosystems. We can't afford to do all that they do.
D) Because we can make lots of money from ecosystems.
E) Because people are in charge of the Earth.

Question 43

What two fields of study did the scientist Robert MacArthur combine?

A) Ecology and zoology
B) Chemistry and ecology
C) Zoology and genetics
D) Math and ecology
E) Math and chemistry

Question 44

What was Robert MacArthur's outstanding contribution to the field of ecology?

A) The description of ecosystem services and the value they provide to us
B) Mathematical models of processes and interactions that could then be tested experimentally
C) The discovery of biogeochemical cycles and the ways we impact them
D) Research on mutualisms between many different organisms
E) Incorporating zoology into the field of ecology

Question 45

What are schistosomes?

A) A type of rock involved in the lithosphere cycle
B) Fig wasps that only pollinate certain rare figs
C) Freshwater parasites that can infect humans
D) An insect that can decimate a cotton field
E) A water pollutant common in nitrogen-enriched water

Question 46

What type of biological control can be used to control schistosomes?

A) Fungi that break apart rocks
B) Natural chemical insecticides that kill off their competitors
C) Crayfish that eat the snails they need to complete their life cycle
D) Lady bug beetles
E) Algae-eating fish

Question 47

What were the causes of the genocide in Rwanda in 1994?

A) It was all due to a loss of ecological services.
B) It was a war between ethnic groups, but destruction of the environment contributed to it.
C) It was a consequence of crowding.
D) It was all a political fight over territory.
E) Nobody really understands what triggered it.

Question 48

What environmental losses may have contributed to the war in Rwanda?

A) Deforestation, overgrazing, and loss of soil all made farming unproductive.
B) Repeated drought conditions made competition for fresh water a factor.
C) Alterations which led to the prevalence of malaria
D) Alterations which led to the prevalence of the disease-causing tsetse flies
E) The main thing was a loss of modern medical care, not so much an ecosystem issue.

Question 49

Why did the National Science Foundation fund the Long-Term Ecological Research network?

A) They have more money than they know what to do with.
B) To keep as many scientists as possible employed
C) Because it can take a long time for changes to occur in an ecosystem, so experiments take a long time
D) Because that allows time for many more experiments that teach us how ecosystems work
E) Because scientists were refusing to do short-term studies since they don't really tell you much

Question 50

In a long-term experiment at Hubbard Brook in New Hampshire, scientists compared an undisturbed valley with a valley that had all the plants removed. What did they discover?

A) Plants produce an important amount of oxygen in an ecosystem.
B) Forests play a minor role in maintaining water quality, and only if it's very rainy.
C) Forests play a major role in reducing water pollution from runoff and in maintaining soil fertility.
D) Without plants, the animal population plummets, but this helps conserve water and nutrients in the system.
E) Plants decompose very slowly and release their nutrients back to the soil.

Question 51

What branch of study in biology looks at interactions between living things and their environment?

Question 52

How does a desert-dwelling kangaroo rat minimize evaporation to conserve water?

Question 53

Why are yellow-bellied marmots in the Rocky Mountains polygynous?

Question 54

If a new species of squirrel is introduced to a habitat which already has a squirrel occupying the required niche of the introduced squirrel, what will probably happen to one of the species?

Question 55

If two species occupy the same niche, what can happen to avoid one of them going extinct?

Question 56

Grazing is an example of what type of interaction between species?

Question 57

Cheetahs eat gazelles. Both can run very fast. This is an example of what phenomenon we see in evolution of species in an exploitative relationship?

Question 58

Pollination is an example of what kind of interaction between species?

Question 59

If you are a pollinator specializing on just one species of plant, you have a reliable source of food, but what is the risk?

Question 60

What do we call the species that end up competing most successfully against humans?

Question 61

Sometimes it's possible to use one living species against another, like when gardeners introduce ladybug beetles to their gardens to eat other insects. What is this type of defense called?

Question 62

Consider a trophic pyramid. At what trophic level would you put a cow?

Question 63

Our atmosphere is full of nitrogen gas, but most living things can't use that directly, although they all need nitrogen to build proteins and make DNA. What types of organisms can use nitrogen gas directly and then enable the rest of us to access it?

Question 64

Of the four categories of service that ecosystems provide, which do humans tend to actually appreciate and assign value to?

Question 65

What is one example of an ecosystem supporting service?