Laurasiatheria Laurasiatheria Laurasiatheria is a clade of placental mammals that originated on the northern supercontinent of Laurasia 99 million years ago. The clade includes shrews, pangolins, bats, whales, carnivorans, odd-toed and even-toed ungulates, among others. Laurasiatheria was discovered on the basis of the similar gene sequences shared by the mammals belonging to it; no anatomical features have yet been found that unite the group. The Laurasiatheria clade is based on DNA sequence analyses and retrotransposon presence/absence data. The name comes from the theory that these mammals evolved on the supercontinent of Laurasia, after it split from Gondwana when Pangaea broke up.
Geology of England Permian, the new continent and another terrane, Armorica which included Iberia, drifted in from Gondwana, trapping Avalonia between it and the continent so adding Iberia/Armorica to Euramerica. This was followed up by the arrival of Gondwana. The effects of these collisions are seen in Europe as the Variscan folding. In North America it shows as later phases of the Acadian orogeny. This was happening at around the Equator during the later Carboniferous, forming Pangaea in such a way that Avalonia was near its centre but partially flooded by shallow sea. In the Jurassic, Pangaea split into Laurasia and Gondwana, with