A multidisciplinary survey of the Padre Nuestro cavern, southeastern Dominican Republic is the goal of this research. The cavern is underwater, but its floor was dry at the time of emplacement of extinct vertebrates and archaeological materials. Primates, rodents and sloths originated in South America and had arrived in the Antilles by the early Miocene, but absence of other typical Miocene South American taxa like carnivorous marsupials, armadillos, and notoungulates suggests that a connection between the continent and the islands were intermittent and subject to biotic or cross-water filters. Padre Nuestro contains thousands of loose bones on its floor that so far include many species of native cavioid rodents and several kinds of ground sloths. A skull of an Antillean primate has already been recovered and conserved. A particular emphasis will be the reassessment of the phylogenetic patterns of the primates and sloths using the new material because this contributes important information to the debate over the biogeographic origins of the Antillean fauna: did vertebrates arrive by a filter or via long-distance over-water sweepstakes dispersal and were there a single or multiple dispersal events? In addition, the cavern contains archaeological material that will improve knowledge of the timing and causes of extinction of sloths and primates in Hispaniola, in particular whether extinction was caused by climate change or was induced by the arrival of humans. If the archaeological remains can be shown to be autochthonous and undisturbed since the time of cave flooding, they represent an unusual insight about the culture of some of the earliest immigrants to the Antilles.
The improved phylogenetic analyses made possible by the recovery of more complete remains of primates and sloths will allow tests of hypotheses regarding how and when these mammals entered the Greater Antilles. Geochemical analyses will provide the first direct evidence about the local environmental conditions under which these vertebrates lived. The research also contributes significantly to the Museo del Hombre Dominican and assists in training of staff in the conservation of bone preserved under these circumstances. The research is part of the effort to strengthen the fragile status of archaeological and paleontological remains and provide further support for stronger protection measures of this and similar sites.
The Padre Nuestro cavern in the southeastern Dominican Republic contains pottery made by members of the late prehistoric Taino culture (ca. 500-1000 years ago), older stone tools made by the first inhabitants of the island (ca. 4000-6000 years ago), and the bones of extinct monkeys, extinct sloths, and other animals. We undertook a preliminary scientific study of the cavern with the goal of recovering as many fossils as possible so as to preserve the threatened record of extinct animals that once lived on Hispaniola. We also wanted to see if we could determine whether humans had anything to do with the extinction of these animal species. Today the cavern is flooded with up to 10 meters of fresh water, but its floor was dry at the time of emplacement of many bones of animals, including small and large rodents, bats, ground sloths, insect-eating mammals, and a monkey called Antillothrix. The cave did not contain remains of rats, pigs, or other animals brought to Hispaniola by Europeans in the time of Columbus. More than 90% of the animal species found in the cave, including the monkey, are now extinct as a consequence of climate change and/or human contact. The research team consisted of divers, archaeologists, geologists, and paleontologists. We collected hundreds of specimens, including many skeletal parts of the extinct monkey. Our research on the monkey shows that it was a small-brained, tree-dwelling, fruit-eating species. Our analysis suggests that the monkeys of the Greater Antilles had an ancient origin (Miocene) and that the Antillean primates form a distinct group of close relatives. They could have been the product of the immigration of one monkey species 10-15 million years ago whose descendants dispersed into Hispaniola, Jamaica, and Cuba. Evidently Antillean monkeys are not the product of several immigrations, nor is it likely that they reached the islands via a land bridge about 30 million years ago, as is sometimes supposed. Research on the relationship between the pottery and stone tools made by humans and the extinct animals is continuing. So far there is no evidence that any of the animals found in the cavern had been butchered or cooked. Intellectual merit: This project: (a) gathered the most complete skeleton of a fossil primate from the Greater Antilles, (b) permitted a reconstruction of the behavioral profile of this extinct species, and (c) contributed significantly to the debate surrounding the place of origin of immigrant monkeys into the Greater Antilles. Broader impacts: The research has contributed significantly to the collections of the Museo del Hombre Dominicano, the national anthropology and archaeology museum. The research has strengthened the fragile status of archaeological and paleontological remains in the Dominican Republicâ€™s Parque Nacional del Este (East National Park) and provides further support for the Dominican governmentâ€™s need to institute stronger protection measures at this and similar sites. (The fossils were recovered just in time to keep them from the hands of looters.) In addition, the project helped to support the research of graduate students at three US institutions (Indiana University, Duke University, and the University of Arkansas) and trained scuba divers in proper techniques for recovering and recording scientific information.