C4.1 Populations and communities (Ecosystems): Practice Questions

Which of the following defines a population in ecology?

According to the competitive exclusion principle (Gause's Law), what is the predicted outcome when two species attempt to occupy exactly the same realized niche in a stable, resource-limited environment?

During the process of secondary succession in an abandoned agricultural field, which change in the community structure is typically observed over time?

Which ecological relationship is characterized by both interacting species benefiting from the association?

When a population reaches its carrying capacity \(K\), which statement accurately describes the relationship between the environmental resistance and the biotic potential?

In ecology, distinguish between a population and a community.

Describe the specific physiological or behavioral change that characterizes the transition from the exponential growth phase to the plateau phase in a population of organisms with a limited food supply.

In an ecosystem where the top predator has been removed, explain how the resulting top-down control loss can lead to a significant decrease in species richness within the producer community.

A population of rabbits introduced onto a small, previously uninhabited island begins to grow. In the first year, there were 50 rabbits. After one year, the population has 65 individuals. During this year, 10 rabbits died, and 25 rabbits were born.
a) Calculate the per capita growth rate (\(r\)) of the rabbit population during this year.
b) Give an example of a density-independent factor that could severely limit this population's growth, regardless of its size.

Ecological succession describes the change in species structure of an ecological community over time.
a) Distinguish between primary succession and secondary succession.
b) Explain the role of pioneer species in establishing a viable environment during primary succession, using an example.