Systematics of the Artiodactyla of China in the 21st century

In this paper, I have introduced the concept of the Evolutionary Species, and shown how it affects the taxonomy of the Artiodactyla of China. The "traditional" taxonomy of the Artiodactyla, which has remained almost unchanged for 100 years, relies on ill-formulated notions of species and subspecies, only slightly modified by the population-thinking of the 1930s. Species are populations (or metapopulations) differentiated by the possession of fixed heritable differences from other such populations (or metapopulations). In the Artiodactyla, there are many more species than "traditionally" recognised; this is by no means a drawback, as it enables the units of biodiversity to be identified in a testable fashion, and brings the taxonomy of large mammals into line with that long practised for small mammals. Species are likely to differentiate where there are natural gaps in the distribution of a genus, such as mountain blocks (for example in the genus Budorcas) or otherwise dissected habitat (for example in the genus Cervus). Natural hybridisation between distinct species is not an uncommon phenomenon, again illustrated well in the genus Cervus, where hybridisation between the elaphus and nippon groups occurs today and evidently occurred in the past, as shown by the distribution of mtDNA.