Thursday 13 June 2019

Muntiacus gigas: A new specimen of the Giant Muntjac from the Early Holocene of northern Vietnam.

Muntjacs, Muntiacus spp., are small solitary Deer found across South, Southeast, and East Asia, though with their earliest fossils found in the Miocene of Central Europe. The genus currently contains about a dozen species, with several having only been described in the last few decades. The living Giant Muntjac was first described from northern Vietnam as Megamuntiacus vuquangensis, in 1994, being placed in a separate genus on account of its larger size, though this was later considered to be erroneous, as the species is not sufficiently genetically distinct to justify this. It was then realised that the species was identical to one described from Hemudu, a Middle Holocene (6000-7000 years old) Neolithic site in Zhejiang Province in eastern China, as Muntiacus gigas, in 1990, and then thought to represent an extinct Muntjac species. Since the Chinese specimen was named first, this name takes precedence, and is considered the valid name for the species. The species is currently confined to the Annamite Mountains of Vietnam, Laos, and Cambodia, with this range inferred mostly from hunting trophies in museum collections, and is currently considered to be Critically Endangered under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species, with a high likelyhood of going extinct within the next 20 years. However, the presence of the species in the Middle Holocene of eastern China suggests that the species once had a much greater range.

In a paper published in the journal Royal Society Open Science on 13 March 2019, Christopher Stimpson of the School of Natural and Built Environment at Queen’s University Belfast, Benjamin Utting of the Department of Archaeology at the University of Cambridge, Shawn O’Donnell, also of the School of Natural and Built Environment at Queen’s University Belfast, Nguyen Huong of the Institute of Archaeology at the Vietnam Academy of Social Sciences, Thorsten Kahlert, again of the School of Natural and Built Environment at Queen’s University Belfast, Bui Manh of the Department of Tourism of Ninh Bình Province, Vietnam, Pham Khanh of the Tràng An Landscape Complex Management Board, and Ryan Rabett, once again of the School of Natural and Built Environment at Queen’s University Belfast, describe a new specimen of Muntiacus gigas from an Early Holocene archaeological site in the Tràng An World Heritage Area in Ninh Binh Province, northern Vietnam.

The Tràng An World Heritage Area lies on the southern margin of the Red River Delta in Ninh Binh Province, northern Vietnam, and comprises a karstified (eroded) limestone massif covered by forest that rises from the coastal plain. The Hang Boi Cave Complex is an archaeological site within this area, comprising a series of interconnecting caverns with a southeast-facing entrance, which shows signs of having been inhabited during the Late Pleistocene and Early Holocene,

The specimen in the study (HBC-27587) comes from a midden pile at the entrance to the cave, comprising largely Mollusc shells, but also bones from other Mammals, Birds and Turtles. The specimen is a partial mandible (jaw bone) identified on the basis of bone and tooth anatomy as belonging to Muntiacus gigas. The specimen has been dated to between 11 100 and 11 400 years old.

Specimen HBC-27587 shown in lateral (b), medial (c), dorsal (d ) views and occlusal surfaces of m2 and m3 (e). All scale bars ¼ 20 mm. Stimpson et al. (2019).

The presence of Muntiacus gigas in the Early Holocene of northern Vietnam is not surprising, given that the species is known to have ranged as far as eastern China in the past. However the environment at Hang Boi is very different to that occupied by the species today, suggesting that it has altered its habits in response to Human pressure; modern Giant Muntjacs are found in dense forests in the Annamite Mountains, sometimes at 1200 m above sealevel. However the Tràng An specimen, while it may have been carried a short distance by Humans before being deposited, appears to have lived in a very different environment, on a lowland plane at most 200 m above sealevel, which is interpreted as having been covered by an open Oak woodland during the early Holocene.

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