image: Morphological variety within the Neotropic's most species-rich marine snail - Polystira. This predatory snail genus comprises hundreds of species and diversified in the Caribbean throughout the period of isthmian evolution. This material relates to a paper that appeared in the Aug. 17, 2016, issue of Science Advances, published by AAAS. The paper, by A. O'Dea at Smithsonian Tropical Research Institute in Balboa, Panama, and colleagues was titled, 'Formation of the Isthmus of Panama.' view more
Credit: Jon Todd