Questions: Community Ecology: Structure and Organization
3 questions to test your understanding
Score: 0 / 3
Question 1 Multiple Choice
A forest plot contains 10 species, but 90% of all individuals belong to just one of them. Which metric best captures this imbalance?
ASpecies richness
BEvenness
CGamma diversity
DHabitat filtering
Species richness only counts the number of species present (10), ignoring relative abundance. Evenness specifically measures how equitably individuals are distributed among species — a community dominated by one species scores low on evenness even if richness is high.
Question 2 True / False
A community with higher species richness will typically be more stable than one with lower species richness.
TTrue
FFalse
Answer: False
The diversity-stability relationship is context-dependent. While some studies show positive links, others show neutral or negative effects depending on the type of stability measured (resistance vs. resilience) and the specific stressors involved. High richness does not guarantee stability.
Question 3 Short Answer
Explain the difference between alpha diversity and beta diversity.
Think about your answer, then reveal below.
Model answer: Alpha diversity is the species diversity within a single site or community; beta diversity measures the turnover or difference in species composition between sites.
Alpha diversity captures local richness (e.g., species in one forest plot). Beta diversity captures how different two communities are from each other — high beta diversity means sites share few species, reflecting habitat heterogeneity or strong environmental gradients. Gamma diversity is the total regional diversity encompassing both.