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Amblypoda
Amblypoda is a taxonomic hypothesis uniting a group of extinct, herbivorous mammals. They were considered a suborder of the primitive ungulate mammals and have since been shown to represent a polyphyletic group.
==Characteristics==
The Amblypoda take their name from their short and stumpy feet, which were furnished with five toes each and supported massive pillar-like limbs. The brain cavity was extremely small and insignificant in comparison to the bodily mass, which was equal to that of the largest rhinoceroses. These animals were descendants of the small ancestral ungulates that retained all the primitive characteristics of the latter, accompanied by a huge increase in body size.
The Amblypoda were confined to the Paleocene and Eocene periods and occurred in North America, Asia (especially Mongolia) and Europe. The cheek teeth were short-crowned (brachyodont), with the tubercles more-or-less completely fused into transverse ridges, or cross-crests (lophodont type), and the total number of teeth was in one case the typical 44, but in another was fewer. The vertebra of the neck unite on nearly flat surfaces, the humerus had lost the foramen, or perforation, at the lower end, and the third trochanter to the femur may have also been wanting. In the forelimb, the upper and lower series of carpal (finger) bones scarcely alternated, but in the hind foot, the astragalus overlapped the cuboid, while the fibula, which was quite distinct from the tibia (as was the radius from the ulna in the forelimb), articulated with both astragalus and calcaneum.
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