Collaborative Research: Gateway to North America--the Great American Biotic Interchange (GABI) in Mexico and Origin of C4 Grassland

合作研究：北美门户——墨西哥大美洲生物交汇处（GABI）与C4草原起源

基本信息

批准号：
1949742
负责人：
Xiaoming Wang
金额：
$ 34.94万
依托单位：
Los Angeles County Museum of Natural History Foundation
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1949742&HistoricalAwards=false
关键词：
Collaborative Research Gateway North America

项目摘要

Historical patterns of animal movements between the Americas are crucial to understanding current ecosystems and natural resources. The Great American Biotic Interchange (GABI) is a highly significant historical event of land animal movements between North and South America, triggered by the emergence of the continent-bridging Isthmus of Panama three million years ago. Isthmus formation substantially modified global ocean circulation, climate, and American ecosystems. Large animals such as giant ground sloths, armored glyptodonts, and terror birds moved northward and became an integral part of North American Ice Age ecosystems. North American elephant-like gomphotheres, horses, deer, camels, and carnivorans expanded into South America and triggered the most recent large mass extinction of native animals on that continent. A joint U.S.-Mexico team will investigate the timing and magnitude of these events in central Mexico, a critical gap in knowledge for GABI vertebrate and plant fossils. Integration of long-term fossil records with paleoenvironmental analysis will permit a more detailed reconstruction of the ecosystem reorganization events that led to today’s biodiversity patterns in the Americas. Broader impacts of the project include the development of Spanish and English museum exhibits and digital media, and research training opportunities for students from groups that are underrepresented in STEM fields.A team of vertebrate paleontologists, structural geologist, functional morphologist, phytolith botanist, and stable isotope geochemist will conduct field investigations in central Mexico to establish an integrated regional chronological framework using radiometric dates, fossil mammal biostratigraphy, and magnetostratigraphy to document succession of GABI immigrants. They will assess associated vegetation change using phytoliths and quantify relationships between herbivore diets and C4 vegetation origin, regional climate, and hydrological cycles in North America using isotope analysis of mammalian dental enamel and paleosol carbonates. Broad inter-continental mammal distributional patterns will be contextualized using network analysis to quantify deep-time biogeographic connectivity. Findings will be used to test hypotheses regarding phylogenetic relationships of key immigrant taxa, timing and delay in dispersal to high latitude regions, and climatic and environmental implications of regional C4 grassland expansion.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.

美洲之间动物运动的历史模式对于了解当前的生态系统和自然资源至关重要。美国伟大的生物交流（GABI）是北美洲和南美洲之间的土地动物运动的一个非常重要的历史事件，这是由三百万年前的巴拿马连续桥梁峡部的出现引发的。地峡地层形成实质上修改了全球循环，气候和美国生态系统。大型动物，例如巨型地面插槽，装甲的凝血管和恐怖鸟类向北移动，并成为北美冰河时代生态系统不可或缺的一部分。北美大象般的gomphotheres，马，鹿，骆驼和美食家扩展到南美，并触发了最新的大量本地动物，而这一持续的动物。美国 - 墨西哥联合团队将调查墨西哥中部这些事件的时机和数量，这是GABI脊椎动物和植物化石的知识差距。长期化石记录与古环境分析的整合将允许对生态系统重组事件进行更详细的重建，从而导致当今美洲的生物多样性模式。该项目的更广泛的影响包括西班牙和英国博物馆展览和数字媒体的发展，以及在STEM领域中代表性不足的学生的研究培训机会。脊椎动物古生物学家，结构地质学家，功能形态学家，Phytolith Botanist和Phytolith Botanist和Phytolith Botanist和稳定的同位素地球化学领域的跨越中心型号的机构，化石哺乳动物的生物学学和磁性造影，以记录GABI移民的继任。他们将使用植物石和C4植被起源，区域气候和北美的水文周期之间使用哺乳动物牙齿搪瓷和古溶质碳酸盐的同位素分析来评估相关的植被变化，并量化草食动物饮食与C4植被起源，区域气候和水文周期之间的关系。使用网络分析将对深度时间的生物地理连接量化的广泛洲际哺乳动物分布模式将进行上下文化。调查结果将用于检验有关关键移民分类单元，时间和延迟到高纬度地区的系统发育关系的假设，以及区域C4草原扩张的气候和环境影响。该奖项反映了NSF的法定任务，并通过使用基金会的知识优点和广泛的影响来评估NSF的法定任务。