安徽东至华龙洞因发现距今约30万年的古人类头骨化石和大量动物化石及石制品受到学术界广泛关注。本文对华龙洞遗址的地质、地貌、沉积物特点及洞穴演化过程与古人类活动的关系进行分析。华龙洞地处扬子陆块区西北缘,周边呈现低山—丘陵—湖泊平原地貌景观。与华龙洞遗址密切关联的岩溶洞穴,发育在上寒武统微晶灰岩和白云质灰岩岩系内,中更新以来的地壳运动和岩溶发育是其形成的主要营力。华龙洞遗址是一处坍塌的洞穴,其发育大致经历发育初期（中更新世早期甚至更早）—稳定发育期（中更新世中期）—坍塌埋藏期（中更新世中晚期）等三个阶段,岩溶发育和洞外溪谷的侵蚀使得原始洞穴和堆积物一起在重力作用下坍塌。洞穴坍塌沉积物主要包括围岩岩块与碎屑、各种岩溶沉积物和文化遗物,胶结坚硬,不规则地埋藏于裂隙和巨石之间。古人类在遗址的活动时间处在距今约30万年前的稳定发育期,石制品和骨骼表面痕迹证据表明,华龙洞古人类具备依据不同原料的特点采取砸击法与锤击法并用的技术策略;石片边缘的使用痕迹和动物骨骼表面痕迹显示,古人类在遗址可能进行过肢解动物的行为。本研究对揭示长江下游中更新世中晚期古人类演化与适应生存行为具有重要意义。

The Hualongdong (HLD) site (latitude 30°06′34.1"N, longitude 116°56′54.2"E, 40 m above sea level) is located in Dongzhi County, Anhui Province, China. It was discovered in 2005. The initial excavations at the HLD site in 2006 yielded a hominin frontal fragment and a lower second molar. Renewed excavations were carried out from 2014 to 2019 field seasons which resulted in the discovery of more than 30 human fossils, an abundance of lithic artifacts and fossil mammal fauna. Biostratigraphic study of faunal remains, as well as Uranium-Thorium dating of speleothems and animal teeth from the brecciated deposits indicated that early human occupied the site most probably took place in the late Middle Pleistocene, ca. 300 ka (270-330 ka). This paper presents the cave development and evolutionary history of the HLD site, and provides explanations of the hominin adapted behavior and the function of the site.

HLD cave is situated in the south slope of a small anticline named Meiyuan Hill. Constrained by the regional geological background, geomorphic features around HLD include lower mountains in the southeast, gentle hills and a lake plain in the northwest. The ancient HLD cave developed in the Upper Cambrian Formation, which consists of banded micritic limestone and dolomitic limestone, materials formed in a deep marine environment, and has been moderately karstified and mineralized over time. The initial formation of the ancient HLD cave likely commenced not later than the early Middle Pleistocene, as many broken speleothems were dated beyond the upper limits of the U-series dating. The original cave deposits were about 20 m higher above its current location, as indicated by the in situ flowstone and stalagmites exposed, which were formed inside the ancient HLD cave. Synsedimentary dismantlement, downward slippage, and bedrock weathering are indicated by the brecciated arrangement of the limestone rock blocks, cemented angular, subangular clasts and archaeological remains within the excavation area. Slipping and collapsing of the cave system proceeded from north to south, probably driven by the down-cutting of the valley and karst erosion.

Bone fragmentation is common and includes both diagenetic and green fractures probably produced by carnivore bone cracking and hominin hammerstone breaking. Additionally, carnivore (tooth pits, gnawing and scores marks) and human (cut marks) actions are documented over the bones. The stone tool assemblage is typical of Mode 1, i.e. the core-and-flake industries. Typologically, the HLD lithic assemblage is small (n=38) and is dominated by quartz (65.8%) and chert (21.1%), plus some lava (10.5%) and limestone (2.6%) artifacts. Most stone tools are complete flakes (60.5%) or debitage (31.6%), with only one specimen each of core, retouched and battered artifact categories. Quartz and lava show fluvial cortex and suggest sourcing from streams, whereas chert nodules derive from the nearby Sinian siliceous carbonate-clastic strata formation. A minimum of 44.4% of the quartz products were obtained through bipolar flaking, whereas all of the chert flakes were knapped with a freehand technique. The raw material quality of chert flakes is high, which may explain heavier reduction observed in their dorsal faces. Most chert flakes show use-wear, probably associated with carcass processing given the presence of cutmarks on some bones.

Although human presence at HLD site is attested by the recovery of their fossils and the small samples of cut-marked bones and stone tools, human activity seems to have been marginal at the site. Two possible scenarios can be deduced, either humans occasionally visited HLD site to briefly process animal remains attracted by carcasses abandoned by carnivores, or natural transport processes such as slope wash or gravity resulted in a fortuitous association between the carnivore-accumulated bone assemblage and lithics.