WM Keck Science
Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has been shown to have survived into the historic (European) era, which contrasts with the situation on some other islands of the West Indies.
McFarlane, D.A. "Late Quaternary Fossil Mammals and Last Occurrence dates from Caves at Barahona, Puerto Rico." Caribbean Journal of Science 35.3 (1999): 238-248.