Question 1

Which of the following best describes the difference between a species' fundamental niche and its realized niche?

Accepted Answer

The fundamental niche is the range of environmental conditions a species could theoretically occupy, while the realized niche is the range it actually occupies due to biotic interactions such as competition and predation.

Question 2

In Joseph Connell's classic barnacle study, which factor primarily limited the lower distribution of Chthamalus barnacles in the intertidal zone?

Accepted Answer

Competition with Balanus barnacles

Question 3

Which of the following is an example of a specialist species, based on niche theory?

Accepted Answer

A koala that feeds exclusively on eucalyptus leaves

Question 4

A plant species is found only in a small region, even though similar habitats exist elsewhere. Which of the following is the best experimental approach to determine if dispersal is limiting its range?

Accepted Answer

Transplant individuals outside their current range and observe if they survive and reproduce.

Question 5

Which of the following is NOT a likely abiotic factor influencing habitat suitability for a species?

Accepted Answer

Predator abundance

Question 6

Why might a population of fish in a lake be unable to colonize a nearby pond, even if the pond has suitable environmental conditions?

Accepted Answer

The fish are limited by a natural barrier to dispersal, such as land between the lake and pond.

Question 7

Which of the following best distinguishes migration from dispersal?

Accepted Answer

Dispersal is a one-way movement to a new location, while migration is a seasonal, round-trip movement.

Question 8

Which of the following scenarios best illustrates the effect of human-caused barriers on dispersal?

Accepted Answer

A highway and urban development fragmenting a forest, preventing small mammals from moving between patches.

Question 9

Which of the following statements about generalist and specialist species is correct?

Accepted Answer

Generalists can utilize a variety of resources and habitats, while specialists are restricted to specific conditions.

Question 10

A population of trees is found in clumped distributions within a landscape. According to the study materials, what is the most likely explanation for this pattern?

Accepted Answer

Resources such as nutrients are clumped in the environment, leading to clumped tree distributions.

Question 11

Which of the following best explains why polar bears are not found in Antarctica, even though the environment is suitable?

Accepted Answer

Polar bears originated in the north and have not dispersed to the southern hemisphere due to historical and geographic barriers.

Question 12

Which of the following is a biotic factor that can limit a species' geographic range?

Accepted Answer

Competition with other species

Question 13

The northern range of the monarch butterfly is limited by the distribution of which of the following?

Accepted Answer

Milkweed plants

Question 14

Which of the following is the best definition of an ecological niche according to Hutchinson?

Accepted Answer

A region in a multi-dimensional space of environmental factors that affect the welfare of a species.

Question 15

A researcher observes that a plant species survives and reproduces when transplanted outside its current range. What is the most likely conclusion?

Accepted Answer

The plant's range is limited by dispersal barriers.

Question 16

Which of the following equations best represents the relationship between a species' fundamental niche (F), realized niche (R), and the effects of biotic interactions (B)?

Accepted Answer

$$R = F - B$$

Question 17

Which of the following is a reason why dispersal is important for populations?

Accepted Answer

It allows populations to avoid crowding, find new resources, and increase genetic variation.

Question 18

Which of the following best describes the relationship between habitat and niche?

Accepted Answer

Habitat is the physical environment where an organism lives, while niche is the organism's role and interactions within that environment.

Question 19

Which of the following is an example of a natural barrier to dispersal?

Accepted Answer

A mountain range separating two valleys

Question 20

Which of the following best explains why the saguaro cactus has a more limited geographic range than the creosote bush?

Accepted Answer

The saguaro cactus is a specialist and is limited by its intolerance to freezing temperatures.

4.3 Population Distribution and Abundance: Ecological Limits and Dispersal

Study Guide - Practice Questions

Study Guide - Flashcards