Summary
Combines the number of species (richness) and their relative abundances (evenness) in a community.
In depth
The Simpson index D = 1 - ฮฃ(n/N)ยฒ. A community of equal abundance of 4 species has higher diversity than one dominated by one species. Diversity is also assessed at alpha (local), beta (between sites) and gamma (regional) scales.
Diversity indices combine richness and evenness. Diversity affects stability and productivity. Sampling effort influences richness estimates.
Key idea: more diverse communities generally respond better to disturbance.
Frequently asked questions
What is Species Diversity?
Combines the number of species (richness) and their relative abundances (evenness) in a community.
Which area of biology covers Species Diversity, and how advanced is it?
Species Diversity is one of the 54 topics in Ecology. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Keystone Species, Macroecology, Microbial Ecology.
Can you give an example of Species Diversity?
A plantation has low diversity compared with natural forest.
What should I learn before Species Diversity?
Work through the Beginner topics in Ecology first, such as Ecology, Ecosystem, Biotic and Abiotic Factors, then return to Species Diversity. Intermediate topics assume the Beginner vocabulary.
What topics are related to Species Diversity?
The closest topics to Species Diversity are Keystone Species, Macroecology, Microbial Ecology, Island Biogeography. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Species Diversity?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Species Diversity. To practise the whole of Ecology, use the Ecology quiz.
How is Species Diversity different from Keystone Species?
Species Diversity: Combines the number of species (richness) and their relative abundances (evenness) in a community. Keystone Species: A species with a disproportionately large effect on its ecosystem relative to its abundance, like sea otters. Read both side by side and note what each one explains.
How should I study Species Diversity step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Keystone Species and explain the difference aloud. Finally, take the Ecology quiz and come back to this page for any question you miss.