Remember classic island biogeography theory? Well, humans mucked that up.

Why do some islands have more species than others? Classic island biogeographic theory says that it is how island habitat diversity and isolation from source pools of species determine species immigration and extinction rates. These two island characteristics are most often measured as geographic area and isolation. But today, humans have altered both characteristics through land development that converts natural areas to anthropogenic areas and international trade that replaces geographic isolation with economic isolation.

iEcoLab postdoc Jason Gleditsch lead a recent paper to contemporize IBT to include anthropogenic metrics of land development and international trade. We then asked if this contemporized theory well explained patterns of native, introduced, and total richness of herps (amphibians and reptiles) across Caribbean Islands. The contemporized theory well explained today’s island biogeographic relationships!


Gleditsch, J., JE Behm, J Ellers, W Jesse, MR Helmus. 2023. Contemporizing island biogeography theory with anthropogenic drivers of species richnessGlobal Ecology and Biogeography. 32(2):233-249. link


Leave a Reply

Your email address will not be published.