Quaternary ice sheets and sea level regression drove divergence in a marine gastropod along Eastern and Western coasts of South America.

ABSTRACT: The southern coastline of South America is a remarkable area to evaluate how Quaternary glacial processes impacted the demography of the near-shore marine biota. Here we present new phylogeographic analyses in the pulmonate Siphonaria lessonii across its distribution, from northern Chile in the Pacific to Uruguay in the Atlantic. Contrary to our expectations, populations from the southwestern Atlantic, an area that was less impacted by ice during glacial maxima, showed low genetic diversity and evidence of recent expansion, similar to the patterns recorded in this study across heavily ice-impacted areas in the Pacific Magellan margin. We propose that Atlantic and Pacific shallow marine hard-substrate benthic species were both affected during the Quaternary in South America, but by differen

SUBMITTER: Fernandez Iriarte PJ 

PROVIDER: S-EPMC6972712 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature