Paleontological investigations to recover fossil monkeys from the middle Cenozoic of South America

点击翻译按钮获取中文摘要

The objective of this project is to recover fossil monkeys in middle Tertiary rocks in Argentina and Bolivia and to place known and new specimens within a more refined chronological framework. Recovery of older monkeys from South America (SA) will contribute important new information to the adaptations of early SA monkeys (also called platyrrhines). New material will shed light on how the relationship of species of monkeys from South America and African. Also, new fossil remains will help to refine our understanding of the origins of the major kinds of platyrrhines, all of which trace back to a common ancestor thought to have lived about 20 million years ago. Finally, new fossil primates may further constrain the time of entry of platyrrhines into South America.The researchers will collect in three areas: 1) the 26 million-year-old rocks of Bolivia which yield the oldest known South American primates; 2) a newly discovered 25 million-year-old locality in the southern Altiplano of Bolivia; 3) Patagonian sites dated at around 20 million years old that contain monkeys and other small mammals; and 4) earlier fossil sites in Patagonia and northern Argentina that preserve small mammals (but not monkeys, as yet) but had a favorable paleoclimate for the occurrence of monkeys and are presently inadequately explored. Rock samples will be collected for 40Ar/39 age determination.