Post K-Pg diversification of the mammalian order Eulipotyphla as suggested by phylogenomic analyses of ultra-conserved elements

The origin of the mammalian order Eulipotyphla has been debated intensively with arguments around whether they began diversifying before or after the Cretaceous-Palaeogene (K-Pg) boundary at 66 Ma. Here, we used an in-solution nucleotide capture method and next generation DNA sequencing to determine the sequence of hundreds of ultra-conserved elements (UCEs), and conducted phylogenomic and molecular dating analyses for the four extant eulipotyphlan lineages—Erinaceidae, Solenodontidae, Soricidae, and Talpidae. Concatenated maximum-likelihood analyses with single or partitioned models and a coalescent species-tree analysis showed that divergences among the four major eulipotyphlan lineages occurred within a short period of evolutionary time, but did not resolve the interrelationships among them. Alternative suboptimal phylogenetic hypotheses received consistently the same amount of support from different UCE loci, and were not significantly different from the maximum likelihood tree topo...

真盲缺目（Eulipotyphla）的起源问题长期存在激烈学术争论，核心争议聚焦于该类群的分化究竟发生于6600万年前的白垩纪-古近纪（K-Pg）界线之前还是之后。本研究采用液相核苷酸捕获技术结合下一代DNA测序，测定了数百个超保守元件（UCEs）的序列，并针对猬科（Erinaceidae）、沟齿鼩科（Solenodontidae）、鼩鼱科（Soricidae）以及鼹科（Talpidae）这四个现存真盲缺目演化支开展了系统发育组学与分子定年分析。采用单模型或分区模型的串联最大似然分析，以及溯祖物种树分析结果显示，四大真盲缺目演化支之间的分化事件发生在一段较短的进化时间窗内，但未能明确它们之间的系统发育关系。不同超保守元件位点对多种次优系统发育假说的支持度始终一致，且与最大似然树拓扑结构并无显著差异……