Abstract
The aim of the present study was to gain a deeper knowledge about the phylogenetic relationships amongst extant mammals, as derived from extensive molecular data sets. Analyses of molecular data gave strong evidence for dividing placental (eutherian) mammals into four major groups. One of these groups, Afrotheria, includes morphologically very distinct mammals such as elephants, sea cows, hyraxes, aardvarks, elephant shrews and two endemic African insectivores: tenrecs and golden moles. Inclusion of golden moles and tenrecs in Afrotheria leads to the conclusion that the present order Insectivora should be divided into two groups, one with African origin and one with Laurasian origin. These two groups of insectivores have originated and evolved independently, showing remarkable parallel adaptive radiations at the morphological level. Most notable are the morphological convergences of Erinaceidae (hedgehogs) versus Echinops (Madagascar 'hedgehogs'); Soricidae (shrews) versus Microgale (shrewlike tenrecs); and Talpidae (moles) versus Chrysochloridae (golden moles). Further, molecular clock estimations suggested that the radiation of the different Afrotheria, which all have African origin, occurred during Africa's isolation in mid Cretaceous to early Cenozoic. In conclusion, a well resolved eutherian tree has been obtained, which displays new and surprising relationships which have never been recognized by morphological or paleontological data
