Discussion

Our primary goal was to assess the interplay between extinction-recolonization dynamics on the one hand, versus isolation and local adaptation on the other, in shaping the dynamics of arthropod communities across a naturally fragmented landscape. Using metabarcoding of whole arthropod communities in kīpuka of different size, we found that forest-specialist arthropods have been isolated by kīpuka fragmentation to the extent that we can detect that they have genetically differentiated over a 150 year timescale. However, we simultaneously used this dataset to demonstrate that species distributed across the kīpuka system have differentiated in entirely different biological communities from one another– suggesting how kīpuka might drive local adaptation to different biotic environments.