105mya Afrotheres

ELEPHANTS, DUGONGS, MANATEES, AARDVARKS, HYRAXES, ELEPHANT SHREWS.

Afrotheria (from Latin Afro- "of Africa" + theria "wild beast") is a clade of mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews (also known as sengis), tenrecs, aardvarks, hyraxes, elephants, sea cows, and several extinct clades. Most groups of afrotheres share little or no superficial resemblance, and their similarities have only become known in recent times because of genetics and molecular studies. Many afrothere groups are found mostly or exclusively in Africa, reflecting the fact that Africa was an island continent from the Cretaceous until the early Miocene around 20 million years ago, when Afro-Arabia collided with Eurasia.

When Africa was an isolated island, members of this clade occupied most of the ecological niches. The small insectivorous afrotheres such as elephant shrews, golden moles, and tenrecs filled the niches of insectivores, the hyraxes filled the roles of rodents and lagomorphs, the aardvarks filled the roles of various medium size ant-eating mammals and proboscideans (elephants and their relatives) filled the roles of large herbivores. The sirenians developed aquatic body plans and started spreading to other parts of the world by water, evolving convergently with the other groups of marine mammals. 

The common ancestry of these animals was not recognized until the late 1990s.  Continuing work on the molecular and morphological diversity of afrotherian mammals has provided ever increasing support for their common ancestry.