After our encounters with Chinese Mountain Cats in Sichuan in 2017, I wrote several articles on this enigmatic and attractive small felid (here, here, here). Over the years, the origins and status of this cat have been discussed. In essence, the argument has been whether it is a full species, Felis bieti, or a subspecies of the Wildcat, here called Felis silvestris. At the time I wrote those articles the view that appeared to prevail was that since it had been reported that the ranges of the Chinese Mountain Cat and the Wildcat overlap, i.e. they are sympatric, they must, therefore, be two different species.
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| These photographs of a Chinese Mountain Cat were taken by Tim Melling in 2019 in the same location we (with Tim) saw them in 2017. This one was crouched next to the road and he took this photograph from the car using torchlight in the pitch dark. The light blue eyes and the ear tufts can be seen. Note the thick, unpointed bushy tail. I wonder if this is the same cat as the one I videod at long range as it patrolled the grassland in 2017? These are from Tim Melling's Flickr pages here |
The Chinese Mountain Cat was first described by the Frenchman of British descent and English surname, Alphonse Milne-Edwards, in 1892. At the time Milne-Edwards was the new Director of the Muséum National d'Histoire Naturelle in Paris. He named the cat, collected in Sichuan, as a new species, Felis bieti, after the French missionary and naturalist, Félix Biet (1838-1901).
Before describing the latest research I must point out that the taxonomy of the various forms of Wildcat in Eurasia and Africa has been the subject of constant change. I am following the authors of the current paper in calling the Wildcat of Europe and parts of Asia, Felis silvestris with five distinct interfertile subspecies or geographical forms, the one in northern China being Felis silvestris ornata. An alternative scheme from 2017 lumped the Wildcats from Africa and Asia into one species, Felis lybica; in that scheme the Wildcat of northern China is Felis lybica ornata. However, that wider problem of Wildcat classification is not germane to the present research on the status of the Chinese Mountain Cat and its relation to the northern Chinese form of the Wildcat.
This week a new paper appeared in Science Advances which specifically addresses the status of the Chinese Mountain Cat. A group of authors from China, Malaysia, Russia and the USA have done a phylogenetic analysis of zoo, museum and villages-kept specimens using nuclear and mitochondrial DNA sequences of 27 Chinese Mountain Cats, 4 Wildcats of the form found in China (Felis silvestris ornata) and 239 domestic cats.
From the phylogenetic analysis, the authors conclude that the Chinese Mountain Cat, which occurs only on the Qinghai-Tibet Plateau, is not a separate species but a subspecies of the Wildcat with a past and complex history of hybridization between the two. Surprise, surprise: Mountain tom cats spreading their genes into the Wildcat population and the offspring back-crossing into the Mountain population appears the most likely explanation for the hybridization events at a time when the ranges of the two forms overlapped. Evidence of extensive past genetic exchange between the two lineages and therefore interbreeding was found
The authors also address the question of whether this conclusion from nuclear and mitochondrial DNA is also compatible with ‘the biological species concept, which considers interbreeding as the prerequisite for a species. The key argument from the proponents for the species status of the Chinese mountain cat lies on its distinctive morphological characters, a presumed sympatric distribution with the Asiatic wildcat, and an absence of gene flow between free-ranging Chinese mountain cats and Asiatic wildcats. However, recent surveys in Northwest China showed that the range attributed to the Asiatic wildcat may have been overestimated and that its presumed presence on the Qinghai-Tibet plateau in north-eastern Qinghai may not be true. That assertion, if proven, would dispute the supposed sympatry of the two lineages’
Differences in appearances were noted in genetically-determined hybrids. For example, the tail was less bushy in a cat with the nuclear DNA of a Mountain Cat and the mitochondrial DNA signature (passed down the maternal line) of a Wildcat. The presence of hybrid cats (i.e. crosses with Wildcat or with domestic cat—see below) could explain the seemingly anomalous appearance of some cats seen and photographed on the Qinghai-Tibet Plateau in recent years.
The authors continued in their conclusion on the Mountain Cat:
Answers to the remaining questions require more surveys and studies to fine map the Asiatic wildcat and Chinese mountain cat distribution in Northwest China; to delineate the subspecies boundaries or hybrid zones; to elucidate the ancestry, adaptation, and evolution of these taxa; and to resolve the historical and current patterns of gene flow among the wildcat and domestic cat lineages in the region.
Will the status and origins of the Chinese Mountain Cat and the other Wildcats of Eurasia and Africa now be regarded as settled? I wouldn’t bet on it although at the moment the ‘lumpers’ certainly hold sway.
The point the authors make on evidence of recent cross-breeding with domestic cats has major implications for the conservation of the Mountain Cat, as the authors explain:
Contemporary genetic introgression from F. s. bieti into sympatric domestic cats is evident across, but not beyond, the range of F. s. bieti. The timing of admixture coincided with large-scale socioeconomic changes in the Tibetan area during the mid-20th century. That process likely led to an expansion of domestic cats into the region and suggests that domestic cats arrived rather late to the Plateau and thus had not encountered F. s. bieti until recently. The increasingly abundant local domestic cat population may pose a threat to the Chinese mountain cat and jeopardize its genetic integrity and evolutionary adaptation to high altitude, an issue with profound conservation implications and worth further study.
Those of us who live in Scotland will recognise the same conservation and taxonomic problems with the Scottish form of the Wildcat. Firstly, survival in the wild is severely threatened by cross-breeding with domestic cats. Secondly, the status of the form has varied from being considered a species (Felis grampia) a separate subspecies of the Wildcat (F. silvestris grampia) or lumped into the European Wildcat (Felis silvestris silvestris). I read that the latter is the currently favoured view.
On that note of deep concern for the future integrity of the Chinese Mountain Cat, the present data supporting ‘lumping’ of the Felis cats mean China loses an endemic species from its faunal list but gains yet another conservation problem.
He Yu, Yue-Ting Xing, Hao Meng, Bing He, Wen-Jing Li, Xin-Zhang Qi, Jian-You Zhao, Yan Zhuang, Xiao Xu, Nobuyuki Yamaguchi, Carlos A Driscoll, Stephen J O’Brien, Shu-Jin Luo. 2021.
Genomic evidence for the Chinese mountain cat as a wildcat conspecific (Felis silvestris bieti) and
its introgression to domestic cats. Science Advances 7 (26), eabg0221. DOI:10.1126sciadv.abg0221
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