Collaborative Research: The geological and paleoecological contexts of early Miocene hominoid evolution

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。该项目通过对一组受地理限制的化石地点的年代学、古生态学和物种多样性的了解，研究了时间和环境在早期类人猿适应性进化中的作用。研究设计包括一系列化石挖掘，以发现早期类人猿及其栖息地的新证据，并结合实验室分析，旨在帮助合成和解释这些发现。该项目的科学重要性在于记录特定的、高度分辨的年代学和生态学背景下的早期类人猿适应多样性，这对解释包括人在内的晚期类人猿的起源和多样性具有重大的下游影响。更广泛地说，该项目通过针对代表性不足群体的培训机会扩大对研究的参与，通过将宝贵但目前无法获取的实地记录数字化来加强科学基础设施，并通过针对博物馆和公立学校的外联活动增加公众对科学的参与。化石和分子证据表明，人类和类人猿的主要谱系在中新世早期(约23-16 Ma)发生了分化。在那个时期，类人猿物种和适应的多样性大大超过了这一群体中的现代变异，这使得很难解释现存的类人猿和人类共有的一系列特征出现的进化顺序和生态背景。这个项目是围绕一个中心问题组织的：早期类人猿之间的差异是否与古环境、年龄或两者的差异有关？为了阐明这些关系，研究人员追求三个具体目标：(1)建立早期类人猿化石地点的严格年代学；(2)为采样不足的类人猿地点产生高分辨率的古生态重建；(3)记录中新世早期类人猿物种的多样性。化石挖掘在一系列露头进行，以更好地记录类人猿的多样性、地质背景和栖息地参数。该项目采用了相关地层剖面的辐射地层学和磁性地层学(目标1)；沉积学、同位素和古生物学分析(目标2)；以及对新的类人猿化石标本进行比较、形态测量和系统发育分析(目标3)。整合这些研究结果可以使研究人员能够将与类人猿和人类谱系中关键特征出现相关的时间和生态参数联系起来，并随后解释这些早期中新世灵长类群落如何对灵长类在广泛地区的分布做出贡献。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). This project examines the roles of time and environment in the adaptive evolution of early apes by advancing knowledge about the chronology, paleoecology, and species diversity for a set of geographically restricted fossil localities. The research design includes a series of fossil excavations to uncover new evidence of early apes and their habitats, combined with laboratory analyses designed to aid in synthesizing and interpreting these discoveries. The scientific importance of this project lies in documenting early ape adaptive diversity within specific, highly-resolved chronological and ecological contexts, with major downstream implications for interpreting the origin and diversification of later apes, including hominins. More broadly, this project expands participation in research through training opportunities targeted to underrepresented groups, enhances scientific infrastructure by digitizing invaluable but currently inaccessible field records, and increases public engagement with science through outreach activities aimed at museums and public schools. Fossil and molecular evidence indicate that the major lineages of humans and apes diverged during the early Miocene (ca. 23-16 Ma). The diversity of ape species and adaptations during that time greatly exceeds modern variation in this group making it difficult to interpret the evolutionary sequence and ecological contexts in which the suite of features shared by living apes and humans appeared. This project is organized around the central question: Are differences among early apes tied to differences in paleoenvironments, ages, or both? To clarify these relationships, researchers pursue three specific aims: (1) establishing a rigorous chronology of early ape fossil sites; (2) generating high-resolution paleoecological reconstructions for undersampled ape localities; and (3) documenting the diversity of ape species during the early Miocene. Fossil excavations are conducted at a series of outcrops to better document ape diversity, geological contexts, and habitat parameters. The project employs radiometric and magnetostratigraphy at correlated stratigraphic sections (Aim 1); sedimentological, isotopic, and paleontological analyses (Aim 2); and comparative, morphometric, and phylogenetic analyses of new fossil ape specimens (Aim 3). Integration of these study results can enable the researchers to contextualize the timing and ecological parameters associated with the emergence of key characteristics in the ape and human lineage, and to subsequently interpret how these early Miocene primate communities contributed to the distribution of primates across broad regions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.