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Mithong, S.

Publications and source records attributed to Mithong, S..

2 recordsLinked to original sources

A comprehensive identification protocol for postcranial bones of Southeast Asian Ruminantia. Part 1: Osteometry

AO_SCPLOWBSTRACTC_SCPLOWTaxonomic identification of animal bone remains from archaeological and paleontological contexts is usually conducted by comparison with modern skeletal specimens, an approach that is relatively straightforward in temperate or insular regions. In contrast, it is more challenging in continental tropical areas, where rich biodiversity makes it difficult to assemble exhaustive modern references. This situation is well illustrated in continental Southeast Asia, where studies of large mammal assemblages have largely focused on teeth and cranial elements, while postcranial remains are rarely investigated. To address this issue, we established an osteometric reference dataset of the limb bones from Southeast Asian ruminant species and analyzed both the potential of raw measurements and osteometric ratios to identify the different taxa. The results reveal significant differences between genera and species, allowing size-based grouping and precise taxonomic identification in some cases. These data were subsequently used to develop an easy-to-use identification tool based solely on measurements. The performance of this tool was tested against previously published datasets, allowing confirmation of existing results, and discussion of potential biases associated with identification based on measurements alone. This new methodological framework provides a solid foundation to be combined with qualitative morphological criteria to enhance the precision and robustness of the taxonomic identifications of subfossil bones from continental southeast Asia.

paleontology↗

Archaeological Bone Assemblages Trace Changes in Turtle and Tortoise Diversity in Continental Southeast Asia

Among tropical regions, continental Southeast Asia is a major hotspot of biodiversity. However, due to rapid urban expansion and severe deforestation, this area is recognized as one of the top global conservation priorities. As in other tropical regions, the prevailing idea is that the decline of local biodiversity in this region is a direct result of the overwhelming environmental changes that have occurred over the last 80 years. However, paleoecological data indicate that tropical forests have been exploited by human populations since at least the Late Pleistocene, and forest clearance for farming began several thousand years ago. To gain a complete overview of the long-term evolution of vertebrate fauna in continental Southeast Asia, it is necessary to investigate the past. This task is currently out of reach, mainly due to the lack of paleontological and historical studies regarding small animals, including emblematic taxa like turtles. Indeed, although some evidence suggests that the biodiversity of turtles in continental Southeast Asia may have changed over the last millennia, the paucity of historical records and archaeological assemblages studies currently precludes further assessment of the potential effect of past environmental changes, including potential human disturbances. The present study consists of a paleontological analysis of turtle bone assemblages collected from four prehistoric sites in Thailand and Cambodia. The aim is to test the hypothesis of changes in turtle biodiversity over the last 10,000 years. Our results indicate that turtle assemblages in most areas have experienced only limited changes across the Holocene, except for Laang Spean in Cambodia. However, a few rare taxa may represent extirpated or extinct species of Testudinidae in continental Southeast Asia at an unknown time during the Holocene. We also observed significant changes in the geographic distribution of some genera, such as Batagur, Cyclemys, and Amyda. The fact that turtle fauna has been rather resilient and unchanged for several millennia shows that past human impact in most investigated areas had limited effects on these taxa. The strong modifications observed in Cambodia could, however, serve as a warning about the potential fate of turtle biodiversity in this region if further loss of natural environments occurs.

paleontology↗