How Do Ecological Communities Change Over Time

question 61

Multiple Choice

How do ecological communities change over time?

• A) Interactions between and among species may cause changes in ecological communities over time.
• B) Keystone species typically become the most common species within an ecological community.
• C) Species richness typically declines as one species outcompetes all other species.
• D) Ecological communities are defined at a given point in time; any change leads to reclassification of the community.

---

Definitions:

Cerebellum

A major structure of the hindbrain that is involved in fine motor coordination, balance, and motor learning.

Maintaining Posture

The process by which organisms keep their body structure in a stable, upright, or specific position.

Language

A system of communication used by a particular community or country, consisting of written, spoken, and sometimes sign forms.

Myelinated Axons

Nerve fibers covered with myelin, a fatty substance that insulates the axon and speeds up the transmission of nerve impulses.