Coupled ESR and U-series dating of the northernmost evidence of Gigantopithecus from Jianshi Longgudong site, China

Gigantopithecus was a great ape once lived in Southeast Asia and China during the Pleistocene, and the northernmost evidence of its presence is presently known from the Longgupo and Jianshi Longgudong sites located in the West-Hubei and Three Gorges region in Southof China. Here, we report the first radiometric dating by ESR/U-series method on mammalian teeth of Jianshi Longgudong site which was found in 1970s, and renowned by the discovery of both possible hominin and Gigantopithecus fossils in association with undoubted stone artifacts. As the cave site was completely emptied by the successive excavations, the analyzed teeth were selected from museum collections while the dosimetry was established from reworked sediments sampled on the site. The results obtained on two fossil teeth from the lower layer 8 give a weighted mean age of 1512 ± 94 ka, while a mean age of 1044 ± 53 ka was obtained for two other teeth from the upper layer 4. These ESR/U-series dating results, in agreement with the fauna record, are younger than the previous paleomagnetic dating interpretation and suggest that Jianshi Longgudong sequence is younger than the Olduvai subchron and the neighboring Longgupo site dated by the same methods to ca 2.2–2.5 Ma.