Describe a situation in which it might be appropriate for a biologist to use only species richness as a measure of biodiversity.

Question

I'm just having trouble grasping this concept.

2.Describe a situation in which it might be more appropriate for a biologist to use a biodiversity index that incorporates both species richness and species evenness.

Answer 1

Generally, species richness and species evenness both indicate the biodiversity of an ecological community. If species evenness is low, this means that there are a lot more individuals from one species compared to another.

Let's say there are 999 flowers in a field. We would say that the field is more diverse in its composition of flowers if there were 333 blue flowers, 333 red flowers, and 333 green flowers (high species evenness) rather than 990 blue flowers, 5 red flowers, and 4 green flowers (low species evenness). Similarly, we would say a field that had 18 different colors of flowers (high species richness) is more diverse than a field with only 3 colors of flowers (low species richness).

There are probably times where a biologist only pays attention to species richness. For example, it may be more important for someone to know how many species of bacteria exist in your gut when studying the effects of probiotic yogurt. Using one measurement or both likely depends on the design of whatever experiment someone is conducting.

I would say that both species richness and species evenness matter in most scenarios.