Biodiversity on island chains: neutral model simulations

A neutral ecology model is simulated on an island chain, in which neighbouring islands can exchange individuals but only the first island is able to receive immigrants from a metacommunity. It is found by several measures that biodiversity decreases along the chain, being highest for the first island. Subtle changes in taxon abundance distributions can be detected when islands in the chain are compared to diversity-matched single islands. The results potentially apply to human microbial diversity, but highlight the difficulty of using static single-site taxon abundance distributions to discriminate between dispersal limitation mechanisms.