BIOS 230 Community Structure and Food Webs - Flashcards

Vocabulary flashcards based on lecture notes about community structure, food webs, diversity indices, and keystone species.

Species Evenness

The abundance of each species relative to the other species within a community. Higher evenness indicates a more balanced community.

Simpson's Index (D)

A measure of community diversity that focuses more on the most abundant species. As D increases, diversity decreases.

Simpson's Diversity Index

Calculated as 1 - Simpson's Index (D). Higher values indicate higher diversity in the community.

Shannon Index (H')

A measure of community diversity that gives more weight to rare species. Higher values indicate higher diversity in the community.

Zonation

Changes in the physical and biological structure of a community as one moves across the landscape.

Dominant Species

Species that have high abundance relative to other species and have significant impacts on the community.

Keystone Species

A species whose absence from a community would bring about significant change in that community, having a disproportionate impact relative to their abundance.