Doctoral Dissertation Improvement: Paleobiology Of Protopithecus Brasiliensis, a Plus-Sized Pleistocene Platyrrhine From Brazil

该项目的目标是重建已灭绝的新世界猴原猿巴西人的古生物学，这是一种从巴西洞穴遗址中发现的鲜为人知的化石，以一具几乎完整的骨架为代表。原猿在系统发育上与现存的吼猴有联系（Alouatta）；两者都有不同寻常的头骨形态，这在功能上与咆哮的发声有关。这项研究的一个主要部分将调查吼猴下颌骨和颅底的形状，以努力验证原始古猿也有一个扩大的舌骨的假设。通过激光扫描和三维数字化捕获的测量将使用几何形态计量学的统计方法进行分析。该项目的另一个组成部分集中在颅后骨骼上，以回答两个独立但相关的问题：1)原始古猿是陆生四足动物的假设是否有证据支持？如果是这样，它将是唯一真正的新大陆陆地灵长类动物，无论是现存的还是灭绝的。2)原始古猿在嚎叫时是否也以与阿鲁阿塔相同的独特方式放置身体，从而在上半身留下独特的骨骼适应性？这个项目的智力价值解决了新世界灵长类动物进化史上的一个巨大缺口。原始古猿是最完整的非人类化石之一，它可以为化石记录中很少有代表性的大型卷尾猴的进化提供很多线索。该项目的广泛影响有几个方面。这一结果将引起公众的兴趣，因为从头骨化石中获得有关社会行为的证据（在这种情况下是发声）的机会很少，而且直观上很有趣。国际合作将通过与保存原始古猿化石的巴西博物馆的研究人员合作来推进。这笔拨款还将帮助支持一名在科学领域工作的女研究生。

The goal of this project is to reconstruct the paleobiology of the extinct New World monkey Protopithecus brasiliensis, a little-studied fossil known from Brazilian cave sites and represented by a nearly complete skeleton. Protopithecus is linked phylogenetically with living howler monkeys (Alouatta); both share aspects of the howler's unusual cranial morphology, which is functionally related to its roaring vocalizations. A major part of this research will investigate the shape of the mandible and cranial base of howler monkeys in an effort to test the hypothesis that Protopithecus also had an enlarged hyoid bone. Measurements captured by laser scanning and 3D digitizing will be analyzed using the statistical approaches of geometric morphometrics.Another component of the project focuses on the postcranial skeleton to answer two separate but related questions: 1) Is there evidence to support a hypothesis that Protopithecus was a terrestrial quadruped? If so, it would be the only truly terrestrial New World primate, extant or extinct. 2) Did Protopithecus position its body in the same unique way that Alouatta does during howling bouts, leaving distinctive skeletal adaptations in the upper body? The intellectual merit of this project addresses a large gap in the evolutionary history of New World primates. Protopithecus is among the most complete non-hominin fossils and it can shed much light on the evolution of the larger, prehensile-tailed monkeys, which are poorly represented in the fossil record. The broader impacts of the project are several. The results will be of interest to the public since opportunities to derive evidence regarding social behaviors, in this case vocalizations, from fossilized skulls is rare and intuitively interesting. International collaborations will be advanced by working with researchers at the Brazilian museum that houses the Protopithecus fossils. This grant will also help to support a female graduate student working in the sciences.