The Quaternary megafauna of Southeast Asia are among the worlds poorest known. Throughout the Pleistocene, continental collisions, active volcanic systems and fluctuations in sea level have had dramatic effects on the region's geography, from southern China to Indonesia. Many Southeast Asian megafauna experienced geographical range reduction or complete extinction during that interval. This thesis explores the relative influence of environmental change and human interaction in these extinctions. There is currently no direct evidence to suggest that humans had a negative impact on Southeast Asian megafauna until the Holocene. Rather, extinctions and geographical range reduction experienced by megafauna are likely to have resulted from of loss of suitable habitats, in particular the loss of more open habitats. Environmental change throughout the Pleistocene of Southeast Asia is reconstructed on the basis of discriminant functions analysis of megafauna from twenty-seven Southeast Asian Quaternary sites, as well as Gongwangling, an early Pleistocene hominin site previously interpreted as paleoarctic. The discriminant functions were defined on the basis of species lists drawn from modern Asian nature reserves and national parks, and were analysed using both taxonomic and phylogeny-free variables. Biases present in these species lists were mitigated against using a range of multivariate techniques. The reconstructions show that Pleistocene environments in Southeast Asia varied from open (e.g. savannah), mixed (woodland) and closed (e.g. rainforest) habitats. Changes in habitats through time are likely to have been driven, at least in part, by changes in sea-level, in turn related to oscillations between glacial and interglacial conditions. The environmental changes associated with these oscillations are likely to have adversely affected many of Southeast Asias megafauna. The Toba super-eruption (~74kya) is unlikely to have been responsible for any of the megafauna extinctions of the Late Pleistocene.
Identifer | oai:union.ndltd.org:ADTP/257624 |
Date | January 2007 |
Creators | Louys, Julien, School of Biological, Earth & Environmental Science, UNSW |
Source Sets | Australiasian Digital Theses Program |
Language | English |
Detected Language | English |
Rights | http://unsworks.unsw.edu.au/copyright, http://unsworks.unsw.edu.au/copyright |
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