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| Xenarthra
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Myrmecophagidae Megalonychidae Bradypodidae Dasypodidae |
It includes the anteaters, sloths, and armadillos. In the past, these families were classified together with the pangolins and AardvarkThis article is about the mammal. See also Aardvark (word). The Aardvark Orycteropus afer [a:dva:k] is a medium-sized mammal native to Africa. The name comes from the Dutch for "earth pig", because early settlers from Europe thought it resembled a pig (al as the order Edentata (meaning toothless, because the members do not have front incisor teeth or molars, or have poorly-developed molars). It was subsequently realised that Edentata was polyphyleticIn biology, a taxon is polyphyletic if it is descended from more than one root form. Scientific classification aims to group species together such that every group is descended from a single common ancestor, and the elimination of groups that are found to—that it contained unrelated families and was thus invalid. Aardvarks and pangolins are now placed in individual orders, and the new order Xenarthra was erected to group the remaining families (which are all related). The name Xenarthra means "strange joints", and was chosen because their vertebraarticulations for the ribs The vertebrae (singular: vertebra) are those bones which compose the spine in vertebrates. There are 33 vertebrae in humans, including the five that are fused to form the sacrum and the four coccygeal bones. The 24 remaining arel joints are unlike those of any other mammals.