Pilosa

Pilosa is a special group of mammals that live in the Americas. This group includes animals like anteaters and sloths, including the extinct ground sloths. The name "Pilosa" comes from a Latin word meaning "hairy," which describes these animals well. These mammals belong to a larger family called xenarthrans and are part of the placental mammals, which means they develop inside their mothers before being born. Studying Pilosa helps us understand how these unique animals evolved and lived in different parts of the world.

Origins and taxonomy

The origins of the Pilosa are not fully known, but they first appeared in South America around 60 million years ago, shortly after the end of the Mesozoic Era. These animals later spread to Central America and North America because of the Great American Interchange. Some sloths also lived on the Antilles, reaching there from South America possibly by floating on natural rafts.

Pilosa, along with armadillos, belong to the larger group called Xenarthra. A special feature of Xenarthra animals is extra bone pieces between certain spine bones. In the past, Pilosa was considered a smaller group inside Xenarthra, but newer ideas treat it as a separate order. Even earlier, Pilosa and armadillos were grouped with pangolins and the aardvark in a group called Edentata, meaning "toothless," because these animals lack front teeth or have weak molars. However, Edentata was later found to include unrelated animals and is no longer used.

Classification

Main article: List of pilosans

The order Pilosa includes animals like anteaters and sloths. Anteaters belong to the suborder Vermilingua, which has one family called Cyclopedidae for silky anteaters and another called Myrmecophagidae.

Sloths are part of the suborder Folivora. This group includes both modern sloths and extinct ground sloths. Modern sloths have families like Bradypodidae for three-toed sloths and Choloepodidae for two-toed sloths. There were also many types of extinct ground sloths in families such as Megalocnidae, Megalonychidae, Megatheriidae, Nothrotheriidae, Mylodontidae, and Scelidotheriidae.