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

阿拉伯位于三大洲的交汇处，连接着非洲、亚洲和欧洲。考虑到这个地理位置，阿拉伯半岛南部的领土可能是连接整个更新世人类的重要途径。事实上，我们物种最多样化和最古老的线粒体（mtDNA）和y染色体（yDNA）遗传谱系聚集在阿拉伯半岛周围，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，表明这条通道是人口流动的双向通道。朝鲜半岛促进了周期性的人口扩张，这并不奇怪。剧烈震荡的上更新世古气候偶尔会将阿拉伯极度干旱的沙漠内部转变为被常年河流和湖泊切割的稀树草原。由于海平面下降，红海沿岸和阿拉伯-波斯湾盆地内的大陆架暴露出来，使一百多万平方公里的土地暴露出来，景观也发生了戏剧性的变化。此外，海平面的下降引发了这些新兴景观中淡水的增加，为阿拉伯的史前居民创造了稳定的避难所。鉴于这种改善和干燥的周期性过程，可以假设阿拉伯在有利时期通过吸引狩猎采集者而起到人口泵的作用；相反，导致他们在干旱开始时收缩回地理上被征召的难民。具有挑战性的气候条件创造了一个负反馈回路，因为环境干燥减少了景观承载能力，并对阿拉伯采集者施加了压力。这个研究项目将调查一个这样的环境避难所：阿曼南部的佐法尔山脉。即使在目前干旱的气候条件下，夏季月份的年季风降雨量也高达400毫米。因此，在气候衰退期间，佐法尔被认为是一个重要的人口撤退地。这一观点得到了来自佐法尔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——这是一个极度干旱的阶段，而此前人们认为半岛不适合居住。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，以及在波动的古气候背景下发展出的适应行为（如果有的话）。PI在整个地区进行的一系列初步调查记录了密集且无处不在的岩屑表面散落在整个景观中，通常与古代湖泊盆地和遗留的排水系统有关。已经对两个就地埋藏的考古遗址进行了测试（al-Hatab岩棚和Ras Aïn Noor），还有其他几个矿床需要进行点蚀测试（见图1、2和3的视觉证据）。将地质景观调查与考古发掘和放射性测年相结合，我们将开始重建佐法尔上更新世的占领序列，以阐明与该生态位相关的狩猎采集者社区的扩张和收缩。

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.