TROPICAL ECOSYSTEM RESPONSE TO LATE-QUATERNARY ENVIRONMENTAL CHANGE: INSIGHT FROM REMARKABLE ASPHALT-PRESERVED BIOTAS

热带生态系统对第四纪晚期环境变化的响应：来自显着的沥青保存生物群的见解

• 批准号: 2146505
• 负责人: Emily Lindsey
• 金额: $ 65.75万
• 依托单位: Los Angeles County Museum of Natural History Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2146505&HistoricalAwards=false
• 关键词: TROPICAL; ECOSYSTEM; RESPONSE; LATE; QUATERNARY

At the end of the last Ice Age, about 12,000 years ago, most of the big animals on Earth went extinct and many ecosystems changed drastically. Scientists still don’t know why these changes happened because the fossil record is incomplete, preserving just brief snapshots in time. An exception are “tar pits,” paleontological sites where asphalt (a type of crude oil) seeped to the surface over thousands of years, preserving fossil remains of whole ecosystems including bones, wood, and insects. In this project, scientists and college students from Los Angeles and Peru will work together to excavate and study fossils from a Peruvian tar pit, reconstructing the biodiverse Ice Age ecosystem and investigating how it changed into the barren desert it is today. This ecosystem collapse occurred during a time of climate changes and human impacts similar to those happening now. It is hoped that studying these past changes can help prevent future extinctions. This project will engage North- and South American students and scientists in recovering, identifying, and describing fossil material from a north-coastal Peruvian asphaltic locality (colloquially, “tar pit”). The curated flora and fauna, comprising plant, small vertebrate, and invertebrate remains, will form a comprehensive and scientifically valuable late-Quaternary fossil collection in this poorly-studied region, and will be analyzed to investigate interactions between humans, climate, and biotic communities. This research will focus on three main questions: (1) What was the late-Quaternary ecosystem structure in the coastal western Neotropics, before the disappearance of the Pleistocene large mammal communities?; (2) How, when, and in response to what climatic and anthropogenic processes did this ecosystem undergo the dramatic ecological state change to its current desertified condition?; and, (3) How did these processes integrate with environmental changes and anthropogenic impacts in other South American regions, leading to a continental – and global – extinction event?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.

在大约12000年前的最后一个冰河时代末期，地球上的大多数大型动物都灭绝了，许多生态系统发生了巨大的变化，因为化石记录不完整，只保留了简短的快照，科学家们仍然不知道为什么会发生这些变化。一个例外是“焦油坑”，这是古生物遗址，沥青（一种原油）在数千年的时间里渗透到地表，保存了包括骨头、木材和昆虫在内的整个生态系统的化石遗迹。在这个项目中，来自洛杉矶和秘鲁的科学家和大学生将共同挖掘和研究秘鲁焦油坑中的化石，重建生物多样性丰富的冰河时代生态系统，并调查它是如何变成今天的贫瘠沙漠的。希望研究这些过去的变化能够帮助防止未来的灭绝，让北美和南美的学生和科学家参与恢复、识别和描述化石材料。秘鲁北部海岸的人沥青地区（俗称“焦油坑”）所整理的动植物群，包括植物、小型脊椎动物和无脊椎动物遗骸，将在这个研究不足的地区形成全面且具有科学价值的晚第四纪化石收藏，并将对其进行分析。研究人类、气候和生物群落之间的相互作用。这项研究将集中于三个主要问题：（1）在生物消失之前，西部新热带地区晚第四纪的生态系统结构是怎样的。更新世的大型哺乳动物群落？；（2）这个生态系统是如何、何时以及对哪些气候和人类活动的影响而经历了目前荒漠化状况的巨大生态状态变化？；（3）这些过程是如何与气候和人类活动相结合的？南美洲其他地区的环境变化和人为影响，导致大陆乃至全球灭绝事件？该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。