Concerted versus independent evolution and the search for multiple refugia: comparative phylogeography of four forest beetles

Phylogeographic structure and its underlying causes are not necessarily shared among community members, with important implications for using individual organisms as indicators for ecosystem evolution, such as the identification of forest refugia. We used mitochondrial DNA (COI), Bayesian coalescent ancestral state reconstruction (implemented in BEAST) and ecological niche models (ENMs) to construct geo-spatial histories for four co-distributed New Zealand forest beetles (Leiodidae, Nitidulidae, Staphylinidae, Zopheridae) to examine the extent to which they have tracked environmental changes together through time. Hindcast ENMs identified potential forest refugia during the Last Glacial Maximum, while ancestral state reconstruction identified key geographic connections for each species, facilitating direct comparison of dispersal patterns supported by the data and the time frame in which they occurred. Well-supported geographic state transitions for each species were mostly between neig...