Question

which of the following best describes the difference between species richness and species evenness in an ecosystem?
a species richness refers to how evenly individuals are distributed among species, while species evenness refers to the total number of species present.
b species richness and species evenness both measure the total number of organisms in an ecosystem.
c species richness is the count of different species in an area, while species evenness describes how evenly individuals are distributed among those species.
d species richness and species evenness are unrelated and do not affect ecosystem health.

Explanation:

Species richness is simply the number of different species in an ecosystem. Species evenness is about the relative abundance of each species. For example, in a forest, species richness would be the count of tree, bird, insect etc. species. Species evenness would tell if there are equal numbers of each species or if one species dominates.

• Option A: Reverses the definitions of species richness and species evenness.
• Option B: Both do not measure the total number of organisms. Species richness is about number of species, evenness about distribution of individuals among species.
• Option C: Correctly defines species richness as count of different species and species evenness as how evenly individuals are distributed among species.
• Option D: Both are related to biodiversity and do affect ecosystem health.

Answer:

C. Species richness is the count of different species in an area, while species evenness describes how evenly individuals are distributed among those species.