Hubbell's Neutral Theory of Ecology

All species ecologically equivalent — diversity driven by drift, speciation & dispersal

Parameters

Species: —   Shannon H: —

Neutral Theory (Hubbell 2001)

Key assumption: All individuals of all species are demographically identical (per-capita birth/death/migration rates equal).

Unified Neutral Biodiversity Number: θ = 2Jm·ν — controls species richness in the metacommunity.

SAR & RSA: Neutral theory predicts species-area relationships and logseries-like rank abundance distributions matching tropical forest data.

Grid: Each cell = one individual. On death, replaced by local birth (1−m) or dispersal from metacommunity (m). Watch species drift to extinction or invasion.