Impact of climate changes from Middle Miocene onwards on evolutionary diversification in Eurasia: insights from the mesobuthid scorpions

The aridification from Middle Miocene onwards has transformed the Asian interior into an arid environment, and the Pleistocene glacial–interglacial oscillations exerted further ecological impact. Therefore, both aridification and glaciation would have considerably influenced the evolution of many mid-latitude species in temperate Asia. Here, we tested this perspective by a phylogeographic study of the mesobuthid scorpions across temperate Asia using one mitochondrial and three nuclear genes. Concordant mitochondrial and nuclear gene trees were obtained, which are consistent with species tree inferred using a Bayesian approach. The age of the most recent common ancestor (MRCA) of all the studied scorpions was estimated to be 12.49 Ma (late Middle Miocene); Mesobuthus eupeus diverged from the clade composing Mesobuthus caucasicus and Mesobuthus martensii in early Late Miocene (10.21 Ma); M. martensii diverged from M. caucasicus at 5.53 Ma in Late Miocene. The estimated MRCA ages of M. mar...

中中新世以来的干旱化过程已将亚洲内陆改造为干旱环境，而更新世冰期-间冰期旋回则带来了进一步的生态影响。因此，干旱化与冰川作用均可能显著影响温带亚洲众多中纬度物种的演化历程。
本研究以分布于温带亚洲的肥足蝎属（Mesobuthus）蝎子为研究对象，依托1个线粒体基因与3个核基因开展系统地理学（phylogeography）研究，以此验证上述推论。研究获得了与线粒体基因及核基因序列一致的基因树，其结果与采用贝叶斯方法推断的物种树相符。
所有受试蝎类的最近共同祖先（most recent common ancestor, MRCA）的估算分化时间为12.49 Ma（晚中新世晚期）；肥足蝎属的Mesobuthus eupeus与由Mesobuthus caucasicus和Mesobuthus martensii组成的演化支于晚中新世早期（10.21 Ma）发生分化；M. martensii与M. caucasicus则在晚中新世的5.53 Ma发生分化。本次估算的M. mar……