Population Movement And Biological Adaptation At High Altitudes

加州大学默塞德分校的Mark Aldenderfer博士将与来自俄克拉荷马大学、芝加哥大学和尼泊尔的同事一起领导一个项目，探索高海拔环境如何影响人员、物质文化、思想和基因的流动。高海拔和高山峡谷是地球上最后几个人类殖民的地方，因为缺氧、寒冷压力和资源的相对稀缺的综合挑战。高山是人口流动和基因流动的障碍，经常在相距很短的山谷系统中造成文化、语言和基因上的隔离。但最关键的是，高海拔环境需要基因适应才能在其中成功永久居住。但是，增加这些基因在现代种群中频率的选择性过程的古老程度尚未得到解决；一些研究人员认为，由于激烈的自然选择，这些基因在人类种群中可以非常迅速地固定下来，而另一些人则认为这个过程发展得慢得多。考古学在研究人类对这些极端环境的生物和文化适应方面具有独特的地位，并研究文化和基因在一段时间内如何相互作用并受到它们的影响。Aldenderfer博士和他的团队将研究在尼泊尔上野马的卡利·甘达基山谷，随着时间的推移，文化、环境和基因相互作用的方式。从历史上看，该山谷是连接印度次大陆和青藏高原的一条关键贸易路线，似乎在大约3000年前首次被占领。虽然这些移民的地理来源不明，但已经假设了三个来源人口：来自印度次大陆的人，来自青藏高原的人，最后是来自中亚经由喜马拉雅西北部的人。为了验证这些假说并确定促进适应高海拔生活的基因的古代性，研究人员将在关键的早期遗址进行挖掘，以恢复更多的物质文化，用于区域比较和人类遗骸，从横跨山谷史前的三个考古时期的人类遗骸中提取古代DNA(ADNA)并进行基因分型，将这三个古代人口的基因构成与当代南亚人、东亚人和西亚欧亚人以及古人类基因组进行比较，以检验关于该地区的人口以及随后迁徙到该地区的假设，最后，估计这些已知促进高海拔适应的古老种群中的基因频率，以测试随着时间的推移这些基因的系统性增加。该项目将培训研究生和博士后研究员在这项研究中开发的尖端aDNA提取和计算方法。研究人员还将促进与尼泊尔合作伙伴开展广泛的教育活动，包括在地区和当地博物馆展示项目成果，并与当地村长就如何保护和维护他们的文化遗产进行接触。

Dr. Mark Aldenderfer, of the University of California, Merced, along with colleagues from the University of Oklahoma, the University of Chicago, and Nepal, will lead a project to explore the ways in which high elevation environments affect the movement of people, material culture, ideas, and genes. High elevation and high mountain valleys were among the last places on the planet colonized by humans due to the combined challenges of hypoxia, cold stress, and the relative scarcity of resources found in them. High mountains act as barriers to population movement and gene flow and often create cultural, linguistic, and genetic isolates in valley systems that are only short distances apart. But most critically, high altitude environments require genetic adaptations for successful permanent habitation in them. But the antiquity of the selective processes that have increased the frequency of these genes in modern populations is unresolved; some researchers argue that these genes can become fixed very rapidly in human populations due to intense natural selection while others suggest the process develops much more slowly. Archaeology is uniquely positioned to study human biological and cultural adaptation to these extreme environments and to look at the ways in which culture and genes have interacted within and been affected by them over the course of time. Dr. Aldenderfer and his team will study the ways in which culture, environment, and genes have interacted over time in the Kali Gandaki valley of Upper Mustang, Nepal. Known from history as a key trade route that connected the Indian subcontinent to the Tibetan plateau, the valley appears to have been first occupied some 3000 years ago. While the geographic origin of these migrants is unknown, three source populations have been hypothesized: peoples from the Indian subcontinent, peoples from the Tibetan plateau, and finally, peoples from Central Asia via the northwestern Himalayas. To test these hypotheses and determine the antiquity of genes that promote adaptation to high elevation life, the researchers will conduct excavations at key early sites to recover additional material culture for regional comparisons and human remains, extract and genotype ancient DNA (aDNA) from the human remains from three archaeological periods that span the prehistory of the valley, compare the genetic make-up of these three ancient populations to contemporary South Asians, East Asians and Western Eurasians as well as archaic human genomes to test hypotheses about the peopling of the region as well as subsequent migrations into it, and finally, estimate the frequency of genes in these ancient populations known to promote high elevation adaptation to test for systematic increases in these genes over time. The project will train graduate students and postdoctoral fellows in the cutting edge aDNA extraction and computational methods developed in this research. The researchers will also foster a wide range of educational activities with their Nepali partners, including the development of displays of project findings in regional and local museums and engagement with local village leaders on how preserve and maintain their cultural heritage.