Afrotheria

Afrotheria is a special group of mammals that mostly live in or come from Africa. This group includes animals like golden moles, elephant shrews, otter shrews, tenrecs, aardvarks, hyraxes, elephants, and sea cows. Even though these animals look very different, scientists found out they are all related because of their genes.

Long ago, Africa was separated from other lands by water. Because of this, many mammals from other places could not come to Africa. Instead, the animals already in Africa, the afrotheres, changed over time to do the same jobs as those other mammals. For example, small afrotheres like elephant shrews acted like insectivores, hyraxes acted like rodents, and aardvarks acted like animals that eat ants found on other continents.

Scientists did not know that all these animals were closely related until the late 1990s. Before that, they thought these animals belonged to different groups. But now, we know they all share a common ancestor and are part of the afrotheres.

Evolutionary relationships

Scientists first suggested the group called Afrotheria in 1998 by studying DNA. Before that, some studies hinted that some African mammals might be closely related. The group includes elephants, sea cows, hyraxes, tenrecs, golden moles, sengis, and aardvarks.

Studies using DNA and body features show that these animals share a common ancestor not shared with other mammals. They often have more vertebrae, special ankle bones, and late-growing teeth. DNA studies also support this group. Afrotheria is one of the three main groups of placental mammals. Scientists think this group began to form about 105 million years ago when Africa was separated from other land masses.

Phylogeny

Current status and distribution

Many Afrotheria animals are in danger of disappearing, which would be a big loss for nature. The IUCN Afrotheria Specialist Group says Afrotheria makes up nearly a third of all mammal groups in Africa and Madagascar, but only 75 of more than 1,200 mammal species there.

Most Afrotheria animals live in Africa, but some, like the Indian elephant and three types of sirenians, live in other places and are also in danger. Long ago, before the Quaternary extinction event, animals like proboscideans lived on every continent except Australia and Antarctica. Hyraxes lived in much of Eurasia not too long ago, at the end of the Pliocene. Some extinct Afrotheria groups, such as embrithopods and desmostylians, were once found all over the world. However, desmostylians might belong to a different group called perissodactyls, but this is still being studied. The exact group for embrithopods is also not fully known.

Classification

Afrotheria is a group of mammals that live mostly in Africa. This group includes animals like aardvarks, elephant shrews, tenrecs, golden moles, hyraxes, elephants, and sea cows. Scientists learned about these connections by studying their genes.

Some of these animals are only found in Africa, showing that Africa was a special place for them to live and change over time.