Collaborative Research: Filling in a temporal gap in hominin evolution

莱迪-杰拉鲁研究项目（LRGP）通过探索埃塞俄比亚阿法尔的一个地区来促进人类起源科学，该地区含有300万至240万年前的稀有化石沉积物。在这一时期，人类谱系中行为和生物进化的证据都是有限的。然而，这些沉积物包含了世界上最早的一些考古遗址，以及人类祖先的化石。将收集新的考古学和古生物学数据，以便更好地了解人类行为进化、南方古猿阿法种的灭绝、石器技术形式的物质文化起源以及古代哺乳动物物种的地理分布。研究人员将研究推动进化的各种因素，如气候变化，以了解人类进化史上发生生物和行为变化的条件。该项目将吸引K-12学生和广大公众的参与;现场调查结果将通过现场的互动博客实时发布，每位科学家将与来自美国教室的学生互动。该项目还有助于培训来自美国和埃塞俄比亚的学生从事STEM科学。在这个为期三年的项目中，研究人员将收集考古学、古生物学和古环境数据，以研究2.95-2.5 Ma时期人类谱系的行为和生物进化。在埃塞俄比亚的阿瓦什河谷下游，A. afarensis在~2.95 Ma（Hadar），其次是石器的出现在~2.58 Ma（Gona）和Homo cf. H. habilis（Hadar）在~2.35 Ma，已被描述为一个激烈的生态位转移的人类谱系。该项目正在研究阿瓦什河谷下游迄今没有记录的一个时期的地层。考古发掘正在以前发现过文物的地方扩大。过去的栖息地，人类存在的将重建多种方法，包括哺乳动物群落结构，利用哺乳动物的饮食，生态形态学，以追溯哺乳动物的运动模式，和植物遗骸的分析。恢复的数据将进行比较，从地方附近的LGRP，包括时间之前和之后，这一间隔开发一个区域，代表性的古环境和物种的营业额跨越时间和空间的人类，动物群和植物学信息。随后，这些数据将进行比较的网站以外的下阿瓦什地区，以更好地了解东非的进化和地理模式。

The Ledi-Geraru Research Project (LRGP) promotes the science of human origins by exploring a region in the Afar of Ethiopia, which contains rare fossiliferous sediments ranging in time from 3.0-2.4 million years ago. The evidence for both behavioral and biological evolution in the hominin lineage is limited during this time period. However, these sediments contain some of the earliest archaeological sites in the world, as well as fossils of human ancestors. New archeological and paleontological data will be collected that provide a better understanding of hominin behavioral evolution, the extinction of Australopithecus afarensis, the origin of material culture in the form of stone tool technology, and the biogeography of ancient mammal species. The investigators will examine the various factors that are driving evolution, such as climate change, to understand the conditions under which biological and behavioral changes occurred in human evolutionary history. The project will engage both K-12 students and the public at large; the immediate field findings will be delivered in a real-time atmosphere through interactive blogs from the field in which each scientist interacts with students from U.S. classrooms. The project is also instrumental in training students from both the U.S. and Ethiopia in a STEM science. During this three-year project, the investigators will collect archaeological, paleontological, and paleoenvironmental data to address behavioral and biological evolution in the hominin lineage in the time period from 2.95-2.5 Ma. In the lower Awash valley of Ethiopia, the last appearance date of A. afarensis at ~2.95 Ma (Hadar), followed by the appearance of stone tools at ~2.58 Ma (Gona) and Homo cf. H. habilis (Hadar) at ~2.35 Ma, have been described as a drastic niche shift for the hominin lineage. This project is examining strata from a period heretofore undocumented in the lower Awash valley. Archaeological excavations are being expanded in locations where artifacts have been previously recovered. Past habitats in which hominins existed will be reconstructed with multiple methods including mammal community structure, utilizing mesowear and stable isotopes for mammalian diets, ecomorphology to retrodict mammal locomotor patterns, and analyses of botanical remains. Data recovered will be compared to hominin, faunal, and botanical information from localities near the LGRP that encompass time before and after this interval to develop a regional, representation of the paleoenvironment and species turnover across time and space. Subsequently, these data will be compared to sites beyond the lower Awash region to better understand East African evolutionary and biogeographical patterns.