Effect of the Central American Isthmus on gene flow and divergence of the American crocodile

The final formation of the Central American Isthmus (CAI) about 3.5 Ma altered global ocean circulation, connected North and South America terrestrial biotas and established the Caribbean Sea. The nature of this event creates a natural scenario to test vicariance, divergence, and speciation by allopatry. Studies have shown the effect of the CAI on marine and terrestrial species, but none have examined a large-bodied amphibious taxon. We used RAD sequencing on populations of the American crocodile (Crocodylus acutus), to study the genomic variation and infer its demographic history .