He is an ISI Highly Cited Researcher and has published over 270 scientific papers in leading international journals including 26 in Science and Nature. 2017 Grotheer, H., Greenwood, P. Coral calcification in a changing World and the interactive dynamics of p H and DIC upregulation. Stegodons are a commonly recovered extinct proboscidean (elephants and allies) from the Pleistocene record of Southeast Asian oceanic islands.Estimates on when stegodons arrived on individual islands and the timings of their extinctions are poorly constrained due to few reported direct geochronological analyses of their remains.The results imply that the rock painting practices at Mt.Huashan probably lasted more than a century, and the Zuojiang rock art is younger than that at Baiyunwan and Cangyuan in Yunnan Province by 1 to 10 centuries.
The rock art and the associated natural scenery at 38 sites located in the Zuojiang River valley, in the southwest of Guangxi Zhuang Autonomous Region, southern China, were inscribed recently on UNESCO’s World Heritage List. Huashan is probably the largest known rock art panel in the world, consisting of approximately 1900 identifiable figures and occupying an area of approximately 8000 m. Huashan, 56 secondary carbonate layers above and below the paintings were studied for their mineralogy, oxygen, and carbon isotopic compositions and dated by the Th/U dating results demonstrate that ages of the rock paintings can be bracketed between 1856±±41yr BP corresponding to the middle to the end of the Eastern Han dynasty (AD 25 to 220).Rock art has been known in Southeast Asia since the early 19th century, but relatively little attention has been paid to this class of archaeological material.This paper attempts to correct the perception that there is little rock art known in the region; especially in the light of intensified research efforts over the last 30 years that have led to the discovery of numerous new sites.Here we report on uranium-series dating of a stegodon tusk recovered from the Ainaro Gravels of Timor.The six dates obtained indicate the local presence of stegodons in Timor at or before 130 ka, significantly pre-dating the earliest evidence of humans on the island.Rock art has been reported in Southeast Asia since the 19th century [1,2,3,4], but mentions of Southeast Asia in the context of world rock art have been scant at best.