Doctoral Dissertation Improvement Grant: Hunter-Gatherers, Archaeogenomics, and the Evolutionary History of the Foxes of California's Channel Islands

古人对环境的最大影响之一是将家养和野生物种引入非本土栖息地。全球化导致了外来物种和入侵物种的迅速传播，但物种通过贸易网络和人类迁徙的流动可以追溯到至少2万年前，并在过去10 000年里加剧。对古代DNA和基因组数据的分析使人们能够调查现在濒临灭绝的岛狐(Urocyon Littoraris)可能在史前被美洲原住民引入或迁徙到加州海峡群岛的情况。海峡群岛拥有北美沿海地区最早的人类占领，距今13,000卡BP，以及一些世界上人口最多的狩猎者-聚集者团体，在岛屿和大陆之间拥有广泛的贸易网络。加州海峡群岛特有的岛狐是联邦政府列入濒危物种名单的物种，一直是相当大的保护研究的主题，包括一项圈养繁殖计划。尽管进行了数十年的研究，但关于狐狸何时殖民英吉利海峡群岛，以及美洲原住民在狐狸引入和扩散到六个岛屿的过程中可能扮演的角色，仍然存在重大问题。大多数研究人员同意，美洲原住民在5000年前故意将岛狐从海峡群岛的北部引入到南部，最近的研究提出了这样一种可能性，即美洲原住民可能首先将狐狸从大陆引入到北部的海峡群岛。这是因为狐狸在六个岛屿上的广泛分布，它们在化石沉积或非常早期的考古背景中的缺失，以及狐狸在美洲原住民宗教和仪式中的重要性。利用考古、历史(19-20世纪)和现存的岛屿狐狸样本，C.Hofman正在描述整个岛屿狐狸基因组中数千个基因位点的遗传变异，以检验狐狸是在全新世由美洲原住民首次引入海峡群岛的假设。通过利用高通量测序确定扩散/引入事件的时间，并将它们置于考古/化石记录的背景下，这项研究将调查人为、生物(其他物种的引入和扩散)和环境因素(例如气候变化)在塑造数千年来岛狐遗传变异中的作用。这些数据将使人们能够更好地了解人类是如何通过将动物引入新的环境来与它们互动和影响它们的，从而模糊了自然和文化之间的区别。这项研究将形成霍夫曼的博士论文，并将发表在同行评议的考古、生物学和跨学科期刊上，以技术报告的形式进行综合，并在海峡群岛国家公园(CHIS)的简短教育文件中进行总结。这个项目将展示将考古学和基因组学结合起来对理解古代和现代人类环境关系和现代保护生物学的重要性。随着时间的推移，对人与动物关系的考古调查可以帮助记录美洲原住民对物种分布、丰度和生态的影响。了解物种和人类在过去如何适应和影响不断变化的环境，将为未来保护、保存和恢复生物多样性的决策提供依据。

One of the greatest environmental impacts of ancient people was the introduction of both domestic and wild species to non-native habitats. Globalization has led to the rapid spread of exotic and invasive species, but the movement of species through trade networks and human migration extends back at least 20,000 years and intensifies during the last 10,000 years. The analysis of ancient DNA and genomic data permits one to investigate the possible prehistoric introduction or movement of the now endangered island fox (Urocyon littoralis) by Native Americans across the California Channel Islands. The Channel Islands contain some of the earliest human occupations in coastal North America at 13,000 cal BP and some of the most populous hunter-gather groups in the world with extensive trade networks between the islands and mainland. The endemic island fox of California's Channel Islands is a federally listed endangered species and has been the subject of considerable conservation research, including a captive breeding program. Despite decades of research, significant questions remain about when foxes colonized the Channel Islands and the role that Native Americans may have played in their introduction and dispersal to six islands. Most researchers agree that Native Americans deliberately introduced island foxes from the northern to the southern Channel Islands by 5,000 years ago, and recent research raises the possibility that Native Americans may have first introduced foxes from the mainland to the northern Channel Islands. This is supported by their widespread distribution on six islands, their absence in fossil deposits or in very early archaeological contexts, and the significance of foxes in Native American religion and ceremony.Using archaeological, historic (19-20th century), and extant island foxes samples, C. Hofman is characterizing genetic variation of thousands of loci across the island fox genome to test the hypothesis that foxes were first introduced to the Channel Islands by Native Americans during the Holocene. By dating dispersal/introduction events and placing them in the context of the archeological/fossil records using high throughput sequencing, this study will investigate the role of anthropogenic, biotic (introduction and dispersal of other species), and environmental factors (e.g. climate change) in shaping island fox genetic variation across several millennia. These data will allow a better understanding of how humans have interacted with and influenced animals by introducing them to new environments, obscuring the distinction between nature and culture. This study will form Hofman's PhD dissertation and will be published in peer-reviewed archaeological, biological, and interdisciplinary journals, synthesized in a technical report, and summarized in a brief educational document for the Channel Islands National Park (CHIS). This project will demonstrate the importance of integrating archaeology and genomics for understanding ancient and modern human environmental relationships and modern conservation biology. Archaeological investigations of human-animal relationships through time can help document the influence of Native Americans on species distribution, abundance, and ecology. Understanding how species and humans adapted to and influenced changing environments in the past will inform decisions about protecting, preserving, and restoring biodiversity in the future.