Biodiversity on island chains: neutral model simulations.

A neutral ecology model is simulated on an island chain, in which neighboring islands can exchange individuals but only the first island is able to receive immigrants from a metacommunity. It is found by several measures that α-diversity decreases along the chain. Subtle changes in taxon abundance distributions can be detected when islands in the chain are compared to diversity-matched single islands. The island chain is found to have unexpectedly rich dynamics. Significant β-diversity correlations are found between islands in the chain, which are absent between diversity-matched single islands. The results potentially apply to human microbial biodiversity and biogeography and suggest that measurements of interindividual and intraindividual β-diversity may give insights into microbial community assembly mechanisms.