Data from: Sea-level driven glacial-age refugia and post-glacial mixing on subtropical coasts, a palaeohabitat and genetic study

Using a novel combination of palaeohabitat modelling and genetic mixture
analyses, we identify and assess a sea-level-driven recolonization process
following the Last Glacial Maximum (LGM). Our palaeohabitat modelling
reveals dramatic changes in estuarine habitat distribution along the coast
of California (USA) and Baja California (Mexico). At the LGM (approx. 20
kya), when sea level was approximately 130 m lower, the palaeo-shoreline
was too steep for tidal estuarine habitat formation, eliminating this
habitat type from regions where it is currently most abundant, and
limiting such estuaries to a northern and a southern refugium separated by
1000 km. We assess the recolonization of estuaries formed during post-LGM
sea-level rise through examination of refugium-associated alleles and
approximate Bayesian computation in three species of estuarine fishes.
Results reveal sourcing of modern populations from both refugia, which
admix in the newly formed habitat between the refuges. We infer a dramatic
peak in habitat area between 15 and 10 kya with subsequent decline.
Overall, this approach revealed a previously undocumented dynamic and
integrated relationship between sea-level change, coastal processes and
population genetics. These results extend glacial refugial dynamics to
unglaciated subtropical coasts and have significant implications for
biotic response to predicted sea-level rise.