关键词: 柳江;更新世晚期;人类演化;头骨特征

Abstract: The cranial and postcranial remains found in Liujiang are the most complete and well-preserved late Pleistocene human fossils ever unearthed in South China. Wu Rukang , who conducted the original study, suggested that even though the Liujiang fossils preserve some primitive, late Pleistocene features, a suite of modern Mongoloid features were also present. Wu considered the Liujiang human as proto-Mongoloid. However, because the exact layer that yielded the fossils is unclear and different radiometric dates exist, the age of the Liujiang fossils remains uncertain. Since the Liujiang discovery (A. D. 1958) many advances have been made in paleoanthropology, with more detailed understanding of geographical and morphological variation, and the mechanisms and possible environmental influences on the evolution of our species. New hypotheses on late Pleistocene human evolution, and the formation and differentiation of modern East Asian populations have been proposed. With these new insights, the Liujiang fossils were re-examined. We proposed the following questions related to Liujiang and late Pleistocene human evolution in East Asia: (1) Does Liujiang’s morphological pattern fit with its suggested minimal age of 67 Ka BP;(2) Compared with modern East Asian populations, how morphologically modern are the Liujiang fossils, and how many derived traits do the Liujiang fossils still exhibit;(3) How different morphologically are the Liujiang fossils compared to the northern Zhoukoudian“( ZKD)”Upper Cave specimens(i. e. , Upper Cave 102 and 103), or to the modern southern Mongoloid populations? With these questions in mind, we analyzed and compared the craniae of Liujiang and ZKD Upper Cave to 1114 modern Chinese craniae of various geographic affinities. Our results show: (1) The expressions of most cranial features on Liujiang fall within the modern range of variation, but there are a few exceptions;(2)Several primitive features like lower orbit can be observed on Liujiang , indicating that it still preserves some late Pleistocene features. However, compared to the late Pleistocene specimens from ZKD Upper Cave, the Liujiang cranium is more modern; (3) The variation between Liujiang and ZKD Upper Cave are mainly in the retention of primitive and robust features on the ZKD Upper Cave craniae. We believe that a small number of these differences may be environmental adaptations, which include the deep depressed nasion on ZKD Upper Cave and the broad nasal bones on Liujiang. Based on these findings, we suggest that the cranial morphology of Liujiang is very close to those of modern Chinese and very few differences exist between them. Concomitantly, our study does not support the supposition that the Liujiang cranium is more primitive than ZKD Upper Cave and Ziyang. Since uncertainty exists of the exact provenience of the human fossils from Liujiang, and due to the similarity of the cranial morphology between Liujiang and modern Chinese, we suggest that the current morphological analysis does not support the earlier age(67 Ka BP)for the Liujiang human fossils.

Key words: Liujiang; Late Pleistocene; Human evolution; Cranial morphology