Variation in the Quaternary Stegodon-Ailuropoda Faunal Complex in Southern China: Upper Pubu Cave (Bubing Basin, Guangxi)

Abstract

The Stegodon-Ailuropoda Faunal Complex is representative of Quaternary faunas across southern China. However, it is becoming increasingly clear that a great deal of variation is present within the faunal complex. Here we report a new late Quaternary faunal assemblage from Upper Pubu Cave, Bubing Basin, Guangxi, southern China. Upper Pubu is a good example of the variation in the Stegodon-Ailuropoda Faunal Complex, particularly when situated in the broader Bubing Basin Quaternary faunal sequence. Upper Pubu was excavated two times resulting in the discovery of 2396 mammalian fossils, consisting mostly of isolated teeth from medium- to large-sized animals. Twenty four mammalian taxa were identified, representative of the Stegodon-Ailuropoda Faunal Complex, including Ailuropoda, Stegodon, Pongo, Rhinoceros, Tapirus, and Elephas. Upper Pubu is dated to 210–100 ka by Uranium-series, electron spin resonance (ESR) and optically stimulated luminescence (OSL) methods. The Upper Pubu fossils largely date to Marine Isotope Stage (“MIS”) 6. Given the severity of the climate during MIS 6, the reduction in both the number and proportion of primates and carnivores in Upper Pubu may be the result of environmental deterioration and a decrease in forested areas towards the end of the Middle Pleistocene (“Chibanian”). It is reasonable to speculate that a predominantly forested and mosaic-like habitat was present during the end of the Middle Pleistocene in southern China – a good example of environmental change during the Quaternary in the region.