Unexpected palaeoecological features of the Middle and Late Pleistocene large herbivores in southwestern Germany revealed by stable isotopic abundances in tooth enamel

摘要

Species flexibility in diet and habitat and their ability to tolerate a range of unfavourable ecological conditions and survive in unusual habitats accompanied by unexpected faunal components has been determined from various research fields. We present the dietary and environmental reconstructions of interglacial and glacial large mammals from central Germany (Bockstein and Vogelherd caves, Steinheim and Mauer) during the Middle and Late Pleistocene, using carbon and oxygen stable isotope relative abundances in the carbonate fraction of tooth enamel. The same species existed in central Europe during different temperature and ecosystem regimes. It appeared that the species during the glacial periods demonstrated much narrower ranges δ~(13)C and δ~(18)O than during the interglacial periods and at the dawn of the species origination. Intriguingly, the early woolly mammoth Mammuthus primigenius fraasi apparently lived in much milder conditions than the late woolly mammoth Mammuthus primigenius primigenius, and shared similar diet and habitat with the straight-tusked forest elephant Palaeoloxodon antiquus. Bovids existed in extremely open habitat at Steinheim, probably during the Saalian glacial, compared to other glacial species. Woolly rhinoceros Coelodonta antiquitatis and the early woolly mammoth came to occupy similar environments only later, during the Weichselian glacial period in Bockstein and Vogelherd caves. A so-called "steppe rhinoceros" Stephanorhinus hemitoechus occurred in the forested habitat, along with the Merck's rhino Stephanorhinus kirchbergensis. The horses appear to have preferred warmer and denser habitat than the woolly rhinoceros during the Pleistocene. The Pleistocene donkeys shared the ecological niches between bovids and horses. These new results demonstrate that stable isotope analyses can be extremely helpful to determine more detailed paleodiet and paleohabitat of extinct species. It appears that the deviation of the inferred palaeoecological patterns from the patterns deduced from modern survivors' ecology increases with increasing age, and species appeared more flexible at their origin.