Late Pleistocene species distribution modelling of North Atlantic intertidal invertebrates

Aim In this study we test molecular-based biogeographical hypotheses of Pleistocene persistence and recolonization in a North Atlantic rocky intertidal invertebrate assemblage using species distribution modelling. Location North Atlantic coastlines. Methods We develop a novel application of species distribution models for intertidal taxa by using both oceanographic and terrestrial environmental variables recently made available at biologically relevant pixel resolutions. We use these model-based distribution estimates to test alternative hypotheses of late Pleistocene history across six amphi-Atlantic taxa whose hypothesized Pleistocene distributions are constructed from previous population genetic inferences. Results Species distribution models correctly estimate all six current amphi-Atlantic distributions on both sides of the Atlantic. Models hindcasted to the Last Glacial Maximum estimate trans-Atlantic distributional persistence in three of six taxa, and conversely indicate no suitable habitat on the North American coastline in the other three taxa. These results are consistent with the histories inferred from population genetic data for five of six of the taxa, the exception being Nucella lapillus, whose hindcasted trans-Atlantic persistence at the Last Glacial Maximum contrasts with the mitochondrial DNA-based estimates of post-glacial expansion from Europe to North America. Main conclusions Marine and terrestrial distribution models are broadly concordant with known contemporary distributions and fail to reject five of six historical distributional hypotheses based on population genetic inferences. This demonstrated utility suggests that this technique could be expanded to examine how Pleistocene and contemporary climate change might play a role in intertidal species distributions across the entire community. Future application and development of these marine and terrestrial distribution models will strengthen inferences regarding the processes generating intertidal community assembly and population divergence, and may assist in conservation planning and the design of marine reserves.