Comparative analyses of past population dynamics between two subterranean zokor species and the response to climate changes

Authors: LIZHOU TANG, LONG YU, WEIDONG LU, JUNJIE WANG, MEI MA, XIAODONG SHI, JIANGANG CHEN, TONGZUO ZHANG

Abstract: The mitochondrial cytochrome b sequences of 34 haplotypes from 114 individuals of Eospalax baileyi and GenBank data of 40 haplotypes from 121 individuals of Eospalax cansus were used to investigate if the Quaternary glaciations on the Qinghai-Tibetan Plateau (QTP) influenced the distribution and colonisation of these 2 species, and if both species presented congruous past population dynamics. The phylogenetic tree indicated a valid status for the genera Eospalax and Myospalax, and an independent species status for E. baileyi and E. cansus. The demographical population history of E. baileyi showed that the effective population size remained stable between 1.00 and 0.50 million years ago (Mya), increased quickly to a peak and fluctuated dramatically between 0.50 and 0.20 Mya, after which a stable level was maintained from 0.20 Mya to the present. The past population dynamics of 3 subgroups of E. cansus exhibited a congruent fluctuation status with E. baileyi from 0.40 to 0.16 Mya, which coincided with the time of the Penultimate Glaciation. This uniform population dynamics changed during the same glacial dates, suggesting that the population history for these 2 species had been influenced by the Penultimate Glaciation of the QTP.

Keywords: Eospalax baileyi, Eospalax cansus, subterranean rodent, past population dynamics, Qinghai-Tibetan Plateau, Penultimate Glaciation

Full Text: PDF