Question 1

An r-selected species is more likely to become an invasive pest than a K-selected species.

Accepted Answer

r-selected species have high reproductive rates and can quickly colonize new environments, making them more likely to become invasive pests. K-selected species have slower reproductive rates and are adapted to stable environments with limited resources, making them less likely to become invasive.

Question 2

A developing nation with a rapidly increasing population is reaching its carrying capacity.What change(s)could allow it to increase its carrying capacity? (Check all that apply)

Accepted Answer

A cultural shift to eating less meat can reduce resource consumption, greater yield from agricultural crops can increase food supply, and water treatment plants can improve health and resource availability, all of which can increase carrying capacity.

Question 3

A group of international students is having a heated discussion in the dining hall."Your country needs to get its population under control!" asserts a student from the United States."Perhaps," replies the Indian student,"But your country ________."

Accepted Answer

The Indian student is bringing attention to the fact that even though their country may have a population control issue, the United States has a much higher per capita resource consumption, which is a significant problem for the planet's sustainability.

Question 4

A rancher is suspected of shooting wolves near Yellowstone National Park,and you have been enlisted to go have a chat with him.The rancher doesn't see any benefit to having the wolves there.What do you say?

Accepted Answer

Choice B correctly explains that without predators like wolves, prey populations (such as jackrabbits) can quickly grow exponentially, leading to overpopulation and ecosystem imbalances. Wolves help keep prey populations in check and reduce their carrying capacity, ensuring a more stable ecosystem.

Question 5

This summer,you are returning to the research station in Costa Rica to follow up on the population of butterflies you have been studying.You are disappointed to find that there are fewer this year than last.In fact,at dinner your friends studying frogs and birds are complaining about the same thing.What type of influence do you suspect?

Accepted Answer

A density-independent effect like environmental disruption is likely the cause because it can affect multiple species regardless of their population density, explaining the simultaneous decline in butterflies, frogs, and birds.

Question 6

An unscrupulous dog breeder has been selecting for dogs that have very large litters,with the goal of maximizing profits.Why might this strategy be counterproductive?

Accepted Answer

Selecting for large litters can lead to malnourished puppies due to competition for resources, and the mother may have reduced ability to care for future litters. This can ultimately lead to reduced profitability rather than maximizing profits.

Question 7

You are working in an aquarium that has been breeding an endangered species of fish for return into the wild.You have a batch of progeny from the first generation of breeding.The staff are discussing whether to return those fish to an area that has been completely depleted,or add them to a partially depleted population."Considering the Allee effect,what do you say?

Accepted Answer

The Allee effect describes how some species benefit from living in large groups, which increases their chances of survival and finding mates. Therefore, the first choice is most appropriate as it suggests that the progeny should be added to the partially depleted population, potentially increasing the size of the school and improving their survival chances and breeding success.

Question 8

A graduate student is studying the feeding behavior of a small octopus that must be laboriously collected from the shores of a remote island.Her intern wishes to do experiments to look at the octopus's mating behavior.Why might the graduate student veto this idea?

Accepted Answer

The graduate student might veto the intern's idea to study the octopus's mating behavior because the octopus has semelparous reproduction, meaning it will die after laying one batch of eggs. This would make it difficult to observe multiple mating behaviors and could also impact the overall survival of the octopus population on the remote island.

Question 9

What would be the best approach to curbing excessive human population growth?

Accepted Answer

Lowering birth rates through education and family planning has been proven to be the most effective approach in curbing excessive human population growth. It enables individuals to make informed decisions about family planning, including the timing and number of children they have. This approach also improves maternal and child health outcomes and reduces the strain on resources necessary to support population growth. A return to historical health care practices, encouraging women to postpone children till after age 35, or embracing traditional agricultural practices may have some benefits, but they are not as effective in reducing population growth as education and family planning.

Quiz 54: Ecology of Individuals and Populations