Diversity Metrics
Species richness S: –
Shannon H: –
Simpson D: –
Most abundant: –
Fundamental θ=Jν: –
UNTB predicts the species-abundance distribution (SAD) under neutral drift. The "fundamental biodiversity number" θ = 2J_M·ν controls richness. Predicted SAD = Fisher log-series (metacommunity) or zero-sum multinomial (local). A key test: does the logseries fit tropical forest data?