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

该项目的目标是在阿根廷和玻利维亚的中第三纪岩石中发现猴子化石，并将已知的和新的标本置于更精细的年代学框架内。从南美洲(SA)恢复年长的猴子将为早期SA猴子(也称为白颈猴)的适应提供重要的新信息。新材料将阐明南美和非洲猴子物种之间的关系。此外，新的化石遗骸将有助于我们完善对主要种类鸭嘴兽起源的理解，所有这些都可以追溯到被认为生活在大约2000万年前的共同祖先。最后，新的灵长类化石可能会进一步限制鸭嘴兽进入南美洲的时间。研究人员将在三个地区收集资料：1)玻利维亚2600万年前的岩石，这些岩石产生了已知的最古老的南美洲灵长类动物；2)玻利维亚南部阿尔蒂普兰诺一个新发现的2500万年前的地点；3)大约2000万年前的巴塔哥尼亚遗址，那里有猴子和其他小型哺乳动物；以及4)巴塔哥尼亚和阿根廷北部的早期化石遗址，保存了小型哺乳动物(但还没有猴子)，但具有有利的古气候，适合猴子的出现，目前还没有得到充分的开发。将采集岩石样品进行40Ar/39年龄测定。

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.