Reconstructing paleoecology for critical transitions in hominin evolution

重建古生态学以了解古人类进化的关键转变

• 批准号: 2051213
• 负责人: Yohannes Ambaye
• 金额: $ 31.1万
• 依托单位: Arizona State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2051213&HistoricalAwards=false
• 关键词: Reconstructing; paleoecology; critical; transitions; hominin

Understanding the paleoecology associated with hominin fossils can advance knowledge about the factors that determined the evolution of the human lineage. In this multidisciplinary project, the researchers reconstruct paleoecology for regions where human ancestor fossils have been recovered from sediments between 3.5 and 3.3 million years ago. They conduct high-resolution, regional-level analyses based on the faunal assemblages from three sites that have a combined area of 3000 square kilometers and reconstruct the paleoecological context immediately preceding the origin of the genus Homo. The project advances undergraduate and graduate training and international research collaborations. Science communication and K-12 science education activities related to the project are designed to increase interest in science and human origins studies and highlight interdisciplinary science and the diversity of people behind the research. This project tests hypotheses related to the emergence of Homo, the apparent extinction of Australopithecus afarensis, and the paleoecological context of co-existing hominin species. Fieldwork is conducted to refine the stratigraphy and age of relevant sections and conduct high-resolution faunal comparisons between sites. Project faunal experts refine the taxonomy of mammalian fossils, collect and analyze taphonomic and paleoecological data, conduct high-resolution, broad-scale reconstruction of paleoenvironment, and assess ecosystem changes prior to the appearance of Homo and disappearance of A. afarensis. For each fossil species in the sample, functional traits of body mass, diet and substrate use are estimated. Diet is estimated through enamel isotopic (δ13C and δ18O) signatures, mesowear and hypsodonty indices. Using correspondence analysis to compare faunal assemblages from the successive time bins and across sites with modern communities, the team estimates biotic and abiotic factors that differed among the three sites and explores how these patterns align with the disappearance of A. afarensis and the appearance of Homo. In addition, species cluster analyses are used to examine biogeographic patterns that emerge, consider taxonomic origins, hypothesize patterns of dispersal, and estimate regional paleoecological patterns.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.

了解与人类化石相关的古生态学可以提高有关决定人类谱系演变的因素的知识。在这个多学科项目中，研究人员重建了对人类祖先化石从3.5到330万年前从沉积物中回收的地区的古生态学。他们基于三个地点的动植物组合进行高分辨率的区域级别分析，这些地点的组合结合面积为3000平方公里，并在同一个人属的起源之前重建了古生态环境。该项目将推进本科和研究生培训以及国际研究合作。与该项目相关的科学传播和K-12科学教育活动旨在增加对科学和人类起源研究的兴趣，并突出跨学科科学以及研究背后的人们的多样性。该项目测试了与HOMO的出现，澳大利亚哲学的近年的明显扩展以及共存人类种类的古生态环境有关的假设。进行实地调查是为了完善相关部分的层学和年龄，并在地点之间进行高分辨率的动物比较。动物动物专家项目完善了哺乳动物化石的分类学，收集和分析了taphonomic和古生态数据，进行高分辨率，大规模重建古环境，并评估生态系统变化，然后再出现同性恋和a。farensis的消失。对于样品中的每种化石物种，估计体重，饮食和底物的功能性状。饮食是通过搪瓷同位素（δ13C和Δ18O）的特征，中核和催眠指标估算的。使用对应分析比较成功的时间箱和具有现代社区的跨越地点的动物组合，该团队估计了三个地点之间有所不同的生物和非生物因素，并探讨了这些模式如何与A. farensis的消失和同性恋的出现保持一致。此外，种类群集分析用于检查出现，考虑分类学起源，假设的分散模式以及估计的区域古生态学模式的生物地理模式。该奖项反映了NSF的法定任务，并通过评估该基金会的智力优点和广泛的影响来评估Criteria，并被认为是值得通过评估的支持。