07 Communities and Ecological Succession Free Online FlashCards

What is a biological community?

A biological community is the populations of different species living and interacting in the same area.

What does an ecosystem include beyond a community?

An ecosystem includes a biological community and its nonliving environment, such as soil, water, and climate.

What does a species’ ecological niche include?

A niche includes the conditions a species tolerates, the resources it uses, and the interactions that shape how it lives.

How can species with overlapping resource needs coexist?

Species can coexist by using shared resources differently, such as feeding at different times or in different parts of a habitat.

What makes a species a keystone species?

A keystone species has an effect on community structure out of proportion to its abundance; removing it can cause widespread changes.

What is mutualism?

Mutualism benefits both species. For example, a pollinator gains nectar while helping a plant reproduce.

How can a predator indirectly increase plant abundance?

A predator that reduces herbivore numbers may indirectly allow plant abundance to increase.

What is ecological succession?

Ecological succession is change in a community’s species composition over time. Its course depends on local conditions and is not a fixed march toward one inevitable endpoint.

Where does primary succession begin?

Primary succession begins where soil is absent or very limited, such as on newly exposed rock after a glacier retreats.

What does species richness measure?

Species richness is the number of species in a community.

What role does a foundation species play?

A foundation species creates or defines habitat that many other organisms use, as reef-building coral does.

What is commensalism?

Commensalism benefits one species while the other is not measurably affected.