A living fossil tale of Pangaean biogeography

摘要: The current distributions of widespread groups terrestrial animals and plants are supposedly the result a mixture either vicariance owing to continental split or more recent trans-oceanic dispersal. For organisms exhibiting vicariant biogeographic pattern—achieving their distribution by riding on plates former supercontinents—this view is largely inspired belief that Pangaea lacked geographical ecological barriers, extinctions dispersal would have erased any signal since early Mesozoic. We here present time-calibrated molecular phylogeny Onychophora (velvet worms), an ancient exclusively panarthropod group distributed throughout Pangaean landmasses. Our data not only demonstrate does need be invoked explain contemporary distributions, but also reveal diversification pre-dates break-up Pangaea, maintaining regionalization even in landmasses remained contiguous history group. These results corroborate growing body evidence from palaeontology, palaeogeography palaeoclimatic modelling depicting over continuous landmass Pangaea.