A species of giant two-humped camel, Camelus knoblochi is known to , lived for about a quarter of a million years in Central Asia. A new study published in Frontiers in Earth Science shows that the last refuge of C. knoblochi it was in Mongolia, until about 27,000 years ago.
In Mongolia, the latter species coexisted with anatomically modern humans and perhaps with extinct Neanderthals or Denisovans. Although the main cause of the extinction of C. knoblochi seems to have been climate change, hunting by archaic humans may also have played a role.
Here we show that the extinct camel Camelus knoblochi persisted in Mongolia until climatic and environmental changes pushed it to extinction about 27,000 years ago said Dr. John W. Olsen, professor emeritus at the University of Arizona School of Anthropology in Tucson, United States.
Paradoxically, southwestern Mongolia is now home to one of the last two populations of the wild Bactrian camel, C. ferus , which is critically endangered. The new results suggest that C. knoblochi coexisted with C. ferus during the late Pleistocene in Mongolia, so interspecies competition may have been a third cause of the extinction of C. knoblochi . Standing nearly three meters tall and weighing over a ton, C. knoblochi would have dwarfed C. ferus . The precise taxonomic relationships between these two species, other Camelus extinct and the ancient Paracamelus are not resolved yet.
According to Olsen:Fossil remains of C. knoblochi from Tsagaan Agui cave in the Gobi Altai mountains of southwestern Mongolia, which also contains a rich stratified sequence of human Palaeolithic cultural material, suggest that archaic peoples coexisted and they interacted there with C. knoblochi and elsewhere, contemporaneously, with the wild Bactrian camel .
The new study describes five leg and foot bones of C. knoblochi found in the Tsagaan Agui cave in 2021, and one from Tugrug Shireet in the current Gobi desert, southern Mongolia. They were found in association with bones of wolves, cave hyenas, rhinos, horses, wild asses, ibex, wild sheep, and Mongolian gazelles. This set indicates that C. knoblochi it lived in mountainous and lowland steppe environments, less dry habitats than those of its modern relatives.
The authors conclude that C. knoblochi eventually became extinct primarily because it was less tolerant of desertification than today's camels, C. ferus , the domestic Bactrian camel C. bactrianus and the domestic Arabian camel C. dromedarius .
In the late Pleistocene, much of the Mongolian environment became drier, changing from steppe to dry steppe and finally to desert.
Apparently, C. knoblochi was poorly adapted to desert biomes, primarily because those landscapes could not support such large animals, but perhaps there were other reasons as well, related to the availability of fresh water and the ability of camels to store water within the body, poorly adapted thermoregulatory mechanisms and competition from other members of the faunal community that occupied the same trophic niche , the authors wrote.
Towards the end, the last individuals of the species may have remained, at least seasonally, in the milder forest-steppe - grasslands interspersed with forests - further north in neighboring Siberia. But this habitat probably wasn't ideal either, which could have spelled C's death. knoblochi . The world would never see giant camels again.
What were the relationships between archaic humans and C. knoblochi ? Dr. Arina M. Khatsenovich, Senior Research Fellow at the Institute of Archeology and Ethnography, Russian Academy of Sciences, Novosibirsk, Russia, said:A C. knoblochi metacarpal bone from Tsagaan Agui cave, dated between 59,000 and 44,000 years ago, it shows traces of both cutting by humans and breakage by hyenas. This suggests that C. knoblochi was a species that late Pleistocene Mongolian humans could hunt or scavenge .
We still do not have enough material evidence for the interaction between humans and C. ferus in the late Pleistocene, but it is probably not different from human relationships with C. knoblochi:as prey, but not as a target of domestication .
First author Dr. Alexey Klementiev, a paleobiologist at the Siberian Branch of the Russian Academy of Sciences, said:We conclude that C. knoblochi became extinct in Mongolia and Asia in general by the end of the marine isotopic stage 3 (approximately 27,000 years ago) as a result of climatic changes that caused the degradation of the steppe ecosystem and intensified the aridification process .