Convergent evolution of SOCS4 between yak and Tibetan antelope in response to high-altitude stress

Convergence often occurs when organisms with different ancestors adopt similar adaptations to environmental stresses. Convergent (sometimes called parallel) evolution at the genetic level is now known to be more common than previously suspected. Studying convergent evolution at the molecular level makes it possible to gain a better understanding of the common mechanisms deployed by different species. Yak (Bos grunniens) and Tibetan antelope (Pantholops hodgsonii), which are endemic to the Qinghai-Tibetan Plateau, both have numerous traits that are adaptive to high altitudes. However, it is still unclear whether these two species have undergone adaptive convergence at the genetic level. We used genomic data to detect possible examples of convergent evolution between yak and Tibetan antelope. We found that one gene, SOCS4, which is involved in the regulation of HIF-1α, showed a signature of convergent evolution. Our results have provided clues that may be important for understanding high-altitude adaptations in animals.