Ancient origin and evolution of the Indian wolf: Evidence from mitochondrial DNA typing of wolves from Trans-Himalayan region and Peninsular India.

Genome Biology 4(6). DOI:10.1186/gb-2003-4-6-p6

Abstract:

The two wolf types found in India are represented by two isolated populations and believed to be two sub-species of Canis lupus. One of these wolf, locally called Himalayan wolf (HW) or Tibetan wolf, is found only in the upper Trans-Himalayan region from Himachal Pradesh to Leh in Kasmir and is considered to be C. lupus chanco. The other relatively larger population is of Indian Gray wolf (GW) that is found in the peninsular India and considered to be C. lupus pallipes. Both these wolves are accorded endangered species status under the Indian Wildlife Protection Act. In 1998 for the first time in India, we initiated molecular characterization studies to understand their genetic structure and taxonomic status. Since then, we have analyzed the genetic variability in 18 of the total of 21 HW samples available in Zoological parks along with representative samples of GW, wild dogs and jackals. Our study of mitochondrial DNA diversity across three different taxonomically informative domains i.e., cytochrome-B gene, 16S rDNA and hypervariable d-loop control region revealed HW to be genetically distinct from the GW as well as from all other wolves of the world, including C. lupus chanco from China. Most importantly, d-loop haplotypic diversity revealed both HW and GW from India to be significantly diverse from other wolf populations globally and showed that these represent the most ancient lineages among them. Phylogenetic analysis revealed the Indian wolves as two independent lineages in a clade distinct and basal to the clade of all wolves from outside of India. Conservative estimate of evolutionary time-span suggests more than one million years of separation and independent evolution of HW and GW. We hypothesize that Indian wolves represent a post-jackal pre-wolf ancestral radiation that migrated to India about 1-2 mya and underwent independent evolution without contamination from other wolf like canids. The study thus, suggests that Indian subcontinent had been one major center of origin and diversification of the wolf and related canids. Further, the significant degree of genetic differentiation of HW from GW and of these two from other wolves, suggest the interesting possibility of them to be new wolf species/subspecies in evolution that may need to be described possibly as C. himalayaensis and C. indica (or as C. lupus himalyaensis and C. lupus indica), respectively. Thus for the first time, the study reveals new ancient wolf lineages in India and also highlights the need to revisit the origin, evolution and dispersion of wolf populations in Asia and elsewhere. Simultaneously, it increases the conservation importance of Indian wolves warranting urgent measures for their effective protection and management, especially of the small HW population that at present is not even recognized in the canid Red List.

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