Phylogeography of the desert scorpion illuminates a route out of Central Asia

Abstract

A comprehensive understanding of phylogeography requires the integration of knowledge across different organisms, ecosystems, and geographic regions. However, a critical knowledge gap exists in the arid biota of the vast Asian drylands. To narrow this gap, here we test an “out-of-Central Asia” hypothesis for the desert scorpion Mesobuthus mongolicus by combining Bayesian phylogeographic reconstruction and ecological niche modeling. Phylogenetic analyses of one mitochondrial and three nuclear loci and molecular dating revealed that M. mongolicus represents a coherent lineage that diverged from its most closely related lineage in Central Asia about 1.36 Ma and underwent radiation ever since. Bayesian phylogeographic reconstruction indicated that the ancestral population dispersed from Central Asia gradually eastward to the Gobi region via the Junggar Basin, suggesting that the Junggar Basin has severed as a corridor for Quaternary faunal exchange between Central Asia and East Asia. Two major dispersal events occurred probably during interglacial periods (around 0.8 Ma and 0.4 Ma, respectively) when climatic conditions were analogous to present-day status, under which the scorpion achieved its maximum distributional range. M. mongolicus underwent demographic expansion during the Last Glacial Maximum, although the predicted distributional areas were smaller than those at present and during the Last Interglacial. Development of desert ecosystems in northwest China incurred by intensified aridification might have opened up empty habitats that sustained population expansion. Our results extend the spatiotemporal dimensions of trans-Eurasia faunal exchange and suggest that species’ adaptation is an important determinant of their phylogeographic and demographic responses to climate changes.

Genetic Structure and Population History of the Zaisan Toad-Headed Agama (Phrynocephalus melanurus) Inferred from Mitochondrial DNA COI Segments

“…This suggests that P. melanurus experienced an expansion and recent stepwise dispersal, which is also supported by the haplotype network analysis revealing a star-shaped topology of IIc3. Similar findings were reported for the desert scorpion Mesobutbus mongolicus [10], agamid lizards Phrynocephalus spp. [3] and the rapid racerunner Eremias velox [8].…”

“…Among these, 11 haplotypes were shared by individuals from several sampling sites. Haplotype 6 and 3 were the most frequent one that comprised in H6 -7 sampling sites (1,2,3,5,6,10,11), and in H3 -5 sampling sites (20,25,(27)(28)(29) respectively. Five haplotypes were shared by as many as 3 sampling sites: H2 -(sites 24, 26, 27), H9 -(sites 32-34), H13 -(sites 1, 2, 4), H16 -(sites 13, 16, 23), H27 -(sites 17,22,25).…”

“…Following Shi et al [10], we reconstructed the spatiotemporal history of P. melanurus throughout their distribution range using the approach of Bayesian phylogeographic diffusion [67] in continuous space implemented in BEAST v.1.10.4 [49]. We analyzed a total of 175 individuals representing 44 sampling localities (Supplementary Materials, Table S1).…”

“…It has been recognized that the climate fluctuations during the Quaternary have greatly impacted the distribution ranges of arid adapted organisms [3][4][5][6]. Thus, many species adapted to the cold and dry environments have recently attracted much attention in the field of biogeography and phylogeography [7][8][9][10][11].…”

Range-Wide Phylogeography and Ecological Niche Modeling Provide Insights into the Evolutionary History of the Mongolian Racerunner (Eremias argus) in Northeast Asia

“…The method of phylogeographic diffusion has been widely used for many species without obvious range barriers to find the most likely distribution of the most recent common ancestor, and to show the dispersal route (e.g., [87]). We therefore used this model to predict the colonization routes of E. argus (Figure 5).…”