The Early Pleistocene Yeka Fauna was first identified during the Hengduan Mountains Scientific Expedition in the 1980s. New mammal fossil remains were collected during the execution of the Second Tibetan Plateau Scientific Expedition and Research Project (STEP) in 2020 and 2024. The most recent findings have been identified as 5 orders, 12 families, 15 genera, and 15 species. The updated Shangri-La fossil mammal combination (Yeka and Zhongdian faunas) has been compared to several Early Pleistocene faunas in China. It has been found to be most closely correlated to the Yuanmou Man Fauna. The faunal composition of the Shangri-La fossil mammal combination is distinguished by the co-occurrence of boreal and austral elements, a pattern that is analogous to the modern biogeography observed in the Hengduan Mountains. Faunal analysis suggests that during the Early Pleistocene, the Shangri-La region was characterized by a moderate-elevation forest intermingled with open grassland.

早更新世叶卡动物群最早发现于20世纪80年代的横断山科学考察中。第二次青藏高原科学考察期间，2020和2024年两次采集到的新的哺乳动物化石标本，经鉴定包含了5目、12科、15属、15种。与中国典型的早更新世哺乳动物群的对比表明，香格里拉地区的化石哺乳动物组合在组成上最接近于元谋人动物群。香格里拉化石哺乳动物组合在动物地理上以南北混合为显著特征，这种模式与横断山现代动物地理格局高度相似。动物组成分析结果反映出早更新世时期，香格里拉地区呈现中等海拔森林和草原镶嵌的环境。