*** Welcome to piglix ***

Afrotheria

Afrotheria
Temporal range: Paleocene - Holocene, 65–0 Ma
Afrotheria.jpg
1. Aardvark 2. Dugong 3. Black and rufous elephant shrew 4. West Indian manatee 5. Golden mole 6. Rock hyrax 7. African bush elephant 8. Tailless tenrec
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Class: Mammalia
Clade: Atlantogenata
Superorder: Afrotheria
Stanhope et al., 1998
Orders

See below


See below

Afrotheria 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. They share few anatomical features but many are partly or entirely African in their distribution. This probably reflects the fact that Africa was an island continent through the early Cenozoic. Because the continent was isolated by water, Laurasian groups such as insectivores, rabbits, carnivorans and ungulates could not become established. Instead, the niches occupied by those groups were filled by tenrecs, hyraxes and elephants that evolved from the ancestral afrothere. This adaptive radiation may have occurred in response to the Cretaceous–Paleogene mass extinction.

The common ancestry of these animals was not recognized until the late 1990s. Historically, the Paenungulata had been linked to other ungulates; the golden mole, tenrecs, and elephant shrews with the traditional (and polyphyletic) Insectivora; and the aardvarks with the pangolins and the xenarthrans within the invalid taxon Edentata. Continuing work on the molecular and morphological diversity of afrotherian mammals has provided ever increasing support for their common ancestry.

The afrotherian clade was originally proposed in 1998 based on analyses of DNA sequence data. However, previous studies had hinted at the close interrelationships among subsets of endemic African mammals, some of these studies date to the 1920s; there were also sporadic papers in the 1980s and 1990s. The core of the Afrotheria consists of the Paenungulata, i.e., elephants, sea cows, and hyraxes, a group with a long history among comparative anatomists. Hence, while DNA sequence data have proven essential to infer the existence of the Afrotheria as a whole, and while the Afroinsectiphilia (insectivoran-grade afrotheres including tenrecs, golden moles, sengis, and aardvarks) were not recognized as part of Afrotheria without DNA data, some precedent is found in the comparative anatomical literature for the idea that at least part of this group forms a clade. The Paleocene genus Ocepeia, which is the most completely-known Paleocene African mammal and the oldest afrotherian known from a complete skull, shares similarities with both Paenungulata and Afroinsectiphilia, and may help to characterize the ancestral body type of afrotherians.


...
Wikipedia

...