Baishiya Karst Cave

Baishiya Karst Cave is located in Ganjia (甘加镇), Xiahe County, Gannan Tibetan Autonomous Prefecture, Gansu, China, on the northeastern edge of the Tibetan Plateau.[2] It lies on the southern side of Dalijiashan Mountain,[1] at the foot of a white cliff.[3] The cave is situated in the Ganjia Basin, at the mouth of the Jiangla River, a tributary of the Yangqu River.[1] The cave is over 1 km (3,281 ft) in length.[1] Within 80 metres (260 ft) from the entrance, the cave's winter daytime temperature is normally 8–9 °C (46–48 °F), suitable for habitation in the harsh winters of the Tibetan Plateau.[4]

Baishiya Karst Cave is a Tibetan Buddhist sanctuary[3] lying north of Baishiya Temple.[1] Said to be a former abode of Padmasambhava and the bodhisattva Tara, it is a popular location for monks to fast and meditate.[2] It is also a pilgrimage site for Tibetan Buddhists and a tourist attraction. In 1982, the 10th Panchen Lama paid homage to the site.[2] According to legend, the cave is more than 50 kilometres (31 mi) long and goes all the way to Xunhua County in Qinghai province.[2]

Xiahe mandible

In 1980, a Tibetan monk who was meditating in the cave discovered the Xiahe mandible. He passed the fossil to Jigme Tenpe Wangchug, the sixth Gungthang tulku, who donated it to Lanzhou University.[3][4][5] The mandible was so unusual that researchers did not know how to classify it.[4][5] Scientists Chen Fahu and Zhang Dongju began studying the site in 2010, while collaboration with the Max Planck Institute for Evolutionary Anthropology began in 2016.[6] The first archaeological survey at the site was performed in 2016, while the first systematic excavation did not take place until 2018.[3] Several lithic artefacts and animal bones with cut marks were discovered at the entrance to the cave.[1]

The Xiahe mandible consists of the right half of a partial mandible with two attached molars.[1] By way of protein analysis, researchers concluded that the Xiahe specimen belonged to a population that was closely related to the Denisovan specimens from Denisova Cave.[6] This is the first time that an ancient hominin was successfully identified using only protein analysis.[7] It is the most complete known Denisovan fossil.[7] Discover, Science News and Nova all named the discovery in their lists of Top Science Stories of 2019.[8][9][10]