Calculate Simpson's Index

Biodiversity: richness (different) and evenness (distribution) of species in an ecosystem

D - diversity: probability that any two eandomly selected species from the sample will be different

N - total number of individual organisms (all species combined)

n - number of individuals of a particular species

D = 1 - (sum n*(n-1)) / (N*(N-1))

0= low diversity

1= high diversity

For example there are 36🐟, 2🐠, and 1🐡

• The🐡won’t count since it is by itself → cannot reproduce and add to diversity in the future

→ the equation is:

1 - (36*(36-1) + 2*(2-1) + 1*(1-1)) / (39*(39-1))

D = 0.15 → 15% chance of randomly picking 2 that are different