Simpson's Diversity Index -Diversity Battle by Latha Pradeep

lathapradeep — 2025-10-15 23:34:27 UTC

Learning Objective

To calculate and interpret Simpson’s Diversity Index in order to compare biodiversity across different ecosystems and understand how species richness and evenness influence ecological stability.

Learning Outcomes (Students Will Be Able To…)

Calculate Simpson’s Diversity Index (D), Diversity (1 − D), and Effective Species Number (1/D)
Compare ecosystems based on dominance vs evenness
Interpret what high or low diversity implies about ecosystem resilience
Evaluate whether species richness alone is enough to measure biodiversity

lathapradeep — 2025-10-15 23:35:29 UTC

calculate:
- D (dominance)
- 1−D (diversity)
- 1/D (effective number of species)
Then compare:
- Which ecosystem is more diverse?
- Does having more species always mean higher diversity?
- How does evenness affect your results?

lathapradeep — 2025-10-15 23:37:35 UTC

Discussion Zone - Critical Thinking Questions for Simpson’s Diversity Index

Conceptual / Interpretation Questions

Is a high 1/D always “better”? Can you think of a situation where lower diversity might actually be beneficial or normal?
Two ecosystems have the same number of species, but one has a lower 1/D. What does that tell you about their structure?
If an ecosystem has high richness but low evenness, is it stable or at risk? Why?
Which is more important - richness or evenness -when determining biodiversity? Justify.

Application to Real World

Imagine you are a conservationist. Which would you protect first -an ecosystem with high richness but low evenness, or low richness but high evenness? Why?
How could human actions (e.g. farming, pollution, urbanization) reduce evenness without reducing total species count?
If a new invasive species enters an ecosystem and becomes dominant, how would that affect D, 1 − D, and 1/D?