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恢复猴子化石，并将已知和新的标本置于更精确的年代框架中。从南美（SA）恢复的老猴子将为早期南美猴子（也称为长颈猴）的适应提供重要的新信息。新材料将揭示南美洲和非洲猴子物种之间的关系。此外，新的化石残骸将有助于我们更好地了解主要种类的扁颈犀牛的起源，所有这些都可以追溯到一个共同的祖先，据认为生活在大约2000万年前。最后，新的灵长目化石可能进一步限制长颈犀牛进入南美洲的时间。研究人员将在三个方面进行收集：1)玻利维亚2600万年前的岩石，那里有已知最古老的南美灵长类动物；2)玻利维亚Altiplano南部新发现的2500万年前的地点；3)距今约2000万年的巴塔哥尼亚遗址中有猴子和其他小型哺乳动物；4)早先在巴塔哥尼亚和阿根廷北部的化石遗址，那里保存着小型哺乳动物（但还没有猴子），但有适合猴子生存的古气候，目前还没有得到充分的探索。将收集岩石样品进行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.