New radiocarbon dates reveal pan-Holocene deposition of rodents at Trouing Jérémie #5, a sinkhole in the western Tiburon Peninsula, Haiti

Abstract

We present eight new radiocarbon dates for endemic and invasive rodents from Trouing Jérémie #5, a paleontologically-rich sink hole on the Tiburon Peninsula, Haiti. This includes new dates for two species that have been previously directly dated ( Isolobodon portoricensis and Brotomys voratus) as well as three endemic rodents which have no previous direct radiometric dates ( Plagiodontia velozi, Hexolobodon phenax, and Rhizoplagiodontia lemkei). The radiocarbon date for P. velozi, the largest of these species, is from the very early Holocene (10,995 ± 190 calendar years before present; Cal BP). Specimens of medium-bodied species, H. phenax and R. lemkei date to the mid-Holocene, while specimens of smaller-bodied I. portoricencis and B. voratus have dates falling in the Late-Holocene. These dates confirm that several of the extinct rodent species coexisted with the first humans, who arrived on the island ca. 6000 years ago. In contrast, murid Rattus specimens date to the last few centuries. Rats arrived with Europeans in the late 15th or early 16th Century and a radiocarbon date of ca. 500 Cal BP for one individual suggests that they likely spread quickly across the island. Collectively, these dates establish that vertebrate accumulations at Trouing Jérémie #5 span the Holocene. Remains from this site may provide a useful time sequence for future work examining ecological change across the Holocene as well as regional extirpation patterns.