Molecular phylogenetic analyses have led to the radical rearrangement of mammalian systematics. Afrotheria, a clade of mammals including elephants and shrew-like animals, are nowadays regarded as the largest group of placental mammals. Long-term isolation has led these animals to develop by adaptive radiation while the Laurasiatheria developed different orders and species on the northern continents.
The other placental animals developed on the northern continent. Another separation occurred between 90 and 95 million years ago: The Euarchontoglires, a mammalian superorder based on molecular genetic sequence analyses, combines the Glires clade, which consists of rodents (Rodentia) and lagomorphs (Lagomorpha) with the Euarchonta, a clade which consists of Scandentia, primates and Dermoptera. The Laurasiatheria evolved into several large orders that phenotypically have little in common, but are nevertheless a monophyletic group. It includes the ungulates, including the whales, odd-toed ungulates, predators, pangolins, bats and insectivora (which are not part of the Afrotheria; today called Eulipotyphla), i.e. shrews, hedgehogs and moles. The complete isolation led to parallel adaptive radiations in Afrotheria and Laurasiatheria. Both groups developed large ungulates, insect eaters and aquatic forms, independently from each other. The separate development ended when the African plate had come close to Laurasia during the Tertiary era, and reduced the Tethys Ocean to a size that no longer prevented mammals from crossing it. 20 to 30 million years ago, the ancestors of those animal groups, which we regard as typically African (with the exception of elephants), came from the north and colonised the African continent.