Huchon Dorothée, Madsen Ole, Sibbald Mark J J B, Ament Kai, Stanhope Michael J, Catzeflis François, de Jong Wilfried W, Douzery Emmanuel J P
Laboratoire de Paléontologie, Paléobiologie et Phylogénie-CC064, Institut des Sciences de l'Evolution UMR 5554/CNRS, Université Montpellier II, Place E. Bataillon, Montpellier Cedex 05, France.
Mol Biol Evol. 2002 Jul;19(7):1053-65. doi: 10.1093/oxfordjournals.molbev.a004164.
Rodentia is the largest order of placental mammals, with approximately 2,050 species divided into 28 families. It is also one of the most controversial with respect to its monophyly, relationships between families, and divergence dates. Here, we have analyzed and compared the performance of three nuclear genes (von Willebrand Factor, interphotoreceptor retinoid-binding protein, and Alpha 2B adrenergic receptor) for a large taxonomic sampling, covering the whole rodent and placental diversity. The phylogenetic results significantly support rodent monophyly, the association of Rodentia with Lagomorpha (the Glires clade), and a Glires + Euarchonta (Primates, Dermoptera, and Scandentia) clade. The resolution of relationships among rodents is also greatly improved. The currently recognized families are divided here into seven well-defined clades (Anomaluromorpha, Castoridae, Ctenohystrica, Geomyoidea, Gliridae, Myodonta, and Sciuroidea) that can be grouped into three major clades: Ctenohystrica, Gliridae + Sciuroidea, and a mouse-related clade (Anomaluromorpha, Castoridae + Geomyoidea, and Myodonta). Molecular datings based on these three genes suggest that the rodent radiation took place at the transition between Paleocene and Eocene. The divergence between rodents and lagomorphs is placed just at the K-T boundary and the first splits among placentals in the Late Cretaceous. Our results thus tend to reconcile molecular and morphological-paleontological insights.
啮齿目是胎盘哺乳动物中最大的目，约有2050个物种，分为28个科。在其单系性、科间关系和分歧时间方面，它也是最具争议的目之一。在此，我们分析并比较了三个核基因（血管性血友病因子、光感受器间类视黄醇结合蛋白和α2B肾上腺素能受体）在涵盖整个啮齿动物和胎盘动物多样性的大型分类抽样中的表现。系统发育结果显著支持啮齿动物的单系性、啮齿目与兔形目（啮齿-兔形类分支）的关联以及啮齿-兔形类+真灵长总目（灵长目、皮翼目和树鼩目）分支。啮齿动物之间关系的分辨率也有了很大提高。目前公认的科在这里被分为七个明确的分支（鳞尾松鼠形亚目、河狸科、栉趾鼠下目、美洲囊鼠总科、睡鼠科、鼠形亚目和松鼠总科），它们可归为三个主要分支：栉趾鼠下目、睡鼠科+松鼠总科以及一个与小鼠相关的分支（鳞尾松鼠形亚目、河狸科+美洲囊鼠总科和鼠形亚目）。基于这三个基因的分子定年表明，啮齿动物的辐射发生在古新世和始新世的过渡时期。啮齿动物和兔形目之间的分歧恰好位于白垩纪-古近纪界线以及晚白垩世胎盘动物的首次分化处。因此，我们的结果倾向于调和分子和形态古生物学的见解。
