Equilibrium species richness on an island balances immigration (decreasing with distance from source) against extinction (decreasing with island area). Predicts species-area relation S = cA^z with z ≈ 0.25 for islands.
Equilibrium species richness on an island balances immigration (decreasing with distance from source) against extinction (decreasing with island area). Predicts species-area relation S = cA^z with z ≈ 0.25 for islands.