Archaeological and Palaeoenvironmental Investigation of Upper Pleistocene human occupation in the Dhofar Mountains, southern Arabia

阿拉伯位于三大洲的连接点，连接非洲，亚洲和欧洲。鉴于这种地理位置，阿拉伯半岛南部的领土可能是整个更新世连接人类的重要通道。事实上，我们物种中许多最多样化和最古老的线粒体（mtDNA）和Y染色体（yDNA）遗传谱系都聚集在阿拉伯半岛周围，这证实了次大陆在现代人类的进化和扩张中发挥了关键作用。一些学者甚至记录了人类向非洲扩张的痕迹，认为这条路径是人口流动的双向通道，半岛促进了周期性的人口扩张也就不足为奇了。剧烈振荡的上更新世古气候偶尔会将阿拉伯半岛极度干旱的沙漠内部转变为被常年河流和干盐湖切割的萨凡纳草原。海平面下降，暴露了红海沿着和阿拉伯-波斯湾盆地内的大陆架，总共暴露了100多万平方公里的土地，也大大改变了地貌。此外，海平面下降引发了这些新兴景观的淡水上升，为阿拉伯半岛的史前居民创造了稳定的避难所。考虑到这种改善和干旱的周期性过程，人们认为阿拉伯半岛是一个人口泵，在有利的时期吸引狩猎采集者;相反，在干旱化开始时，使他们回到地理上被征召的避难所。恶劣的气候条件造成了一个负反馈循环，因为环境干燥降低了景观承载能力，并对阿拉伯觅食者施加了压力。本研究项目将调查这样一个环境避难所：阿曼南部的佐法尔山脉。即使在目前干旱的气候状况下，每年的季风降雨在夏季的几个月里也能带来高达400毫米的降雨量存款。因此，佐法尔被认为是气候衰退期间重要的人口撤退地。这得到了来自佐法尔的al-Hatab Rockshelter的新证据的支持，在那里发现了人类在更新世末期居住的证据-一个极度干旱的阶段，当时半岛以前被认为是不适合居住的。在佐法尔的研究允许探索一个潜在的重要避难所，以确定人类居住的当地记录和适应行为（如果有的话）是在古气候波动的背景下发展起来的PI在整个地区进行的一系列初步调查记录了密集和无处不在的石质表面散布在整个景观中，通常与古老的湖泊盆地和残留的排水系统有关。已经对两个原地埋藏的考古遗址（al-Hatab rockshelter和Ras Aïn Noor）进行了测试，其他几个矿床需要进行坑蚀测试（见图1、图2和图3中的视觉证据）。将地质景观调查与考古发掘和放射性测年编织在一起，我们将开始重建佐法尔上更新世的占领序列，以阐明与此生态位相关的狩猎采集社区的扩张和收缩。

Arabia is situated at the nexus of three continents, connecting Africa, Asia, and Europe. Given this geographic position, the territory of southern Arabia may have served as an important pathway linking hominins throughout the Pleistocene. Indeed, many of our species' most diverse and ancient mitochondrial (mtDNA) and Y-chromosome (yDNA) genetic lineages cluster around the Arabian Peninsula, confirming that the subcontinent played a critical role in the evolution and expansion of modern humans. Some scholars have even documented traces of a human expansion back into Africa, suggesting that this pathway was a bidirectional conduit of population movement.It is not surprising that the peninsula facilitated periodic population expansions. The drastically oscillating Upper Pleistocene palaeoclimate occasionally transformed Arabia's hyperarid desert interior into savannah grasslands incised by perennial rivers and playa lakes. The landscape was also dramatically altered by depressed sea levels that exposed the continental shelf along the Red Sea and within the Arabo-Persian Gulf basin, together exposing over one million square kilometres of land. In addition, reduced sea levels triggered increased freshwater upwelling across these emerged landscapes, creating stable refugia for Arabia's prehistoric inhabitants. Given this cyclical process of amelioration and desiccation, it is posited that Arabia served as a demographic pump by drawing in hunter-gatherers during favourable phases; conversely, causing them to contract back into geographically conscripted refugia at the onset of aridification. Challenging climatic conditions created a negative-feedback-loop, as environmental desiccation reduced landscape carrying capacity and exerted pressure on Arabian foragers.This research project will investigate one such environmental refugium: the Dhofar Mountains in southern Oman. Even under the present arid climatic regime, the annual monsoon rains deposit up to 400 mm of rainfall during the summer months. Therefore, Dhofar is posited to have served as an important population retreat during climatic downturns. This is supported by new evidence from al-Hatab Rockshelter in Dhofar, where evidence of human occupation during the Terminal Pleistocene has been found - a hyperarid phase when the peninsula was previously thought to have been uninhabitable.Research in Dhofar permits the exploration of a potentially important refugium to determine the local record of human occupation and what adaptive behaviours (if any) developed amidst the backdrop of a fluctuating palaeoclimate. A series of preliminary investigations conducted by the PI throughout the region have recorded dense and ubiquitous lithic surface scatters across the landscape, often found in association with ancient lake basins and relict drainage systems. Two in situ buried archaeological sites have been tested (al-Hatab rockshelter and Ras Aïn Noor), with several other deposits requiring test-pitting (see Figures 1, 2, and 3 in visual evidence). Weaving together geological landscape survey with archaeological excavation and radiometric dating, we will begin to reconstruct the sequence of Upper Pleistocene occupation in Dhofar to articulate the expansion and contraction of hunter-gatherer communities associated with this niche.