Long-Term Isotope Evidence on the Diet and Habitat Breadth of Pleistocene to Holocene Caprines in Thailand: Implications for the Extirpation and Conservation of Himalayan Gorals

摘要: Three taxa within the subfamily Caprinae (Himalayan goral Naemorhedus goral, Chinese griseus, and Sumatran serow Capricornis sumatraensis) live in mountainous upland forests of Southeast Asia, where they are considered as vulnerable or near threatened species. Co-occurrences between these two recognized genera have been documented from some Pleistocene fossil sites Thailand, suggesting more widely overlapping distribution past than today. However, diet habitat preferences present-day coexisting species rarely investigated so far. For three decades, stable carbon oxygen isotope analyses become commonplace ecological investigations, allowing us to explore diets habitats ancient extant animals well reconstruct environmental conditions past. Here we reconstructed five Thailand during 400,000 years (from Middle Early Holocene) modern wildlife, using isotopic analysis carbonate tooth enamel order test co-occurrence patterns examine possible changes their niche breadths over evolutionary time. Our revealed remarkably different Capricornis. The has a greater generalist both Himalayan gorals that fed on pure C4 mixed C3 plants restricted an open landscape habitat, its population occupies closed-canopy forest. This suggests contraction wildlife is likely due Holocene climate change human impacts Thai ecosystems. In addition loss reduction grasslands after latest when rainforests became dominant besides hunting predation pressure, high interspecific competition contributed extirpation Thailand. Developing strategic plan for future biodiversity conservation, long-term historical approach implemented allowed predict contrasting suitability, lowland grassland, testified by persistence Pleistocene.