ANT415H5 Lecture Notes - Lecture 8: Metapodial, Ungulate, Digitigrade
Document Summary
Mammal locomotor adaptations the way animals move really affect their body structure. Generalized ancestral mammal limbs ancestral limb is the 5 digits in manus. Plantigrade animals that walk flat on their foot: bears, squirrel, humans. Digitigrade animals that walk on their toes metapodials are elongated and functionally part of the limb. Unguligrade lateral metapodia and digits have been drastically reduced. Only the last phalanx touches the ground first and second phalanges are functionally part of the limb. Hoofed mammals hoof is a hard-keratinized sheath that covers the distal phalanx. Perissogactyls third metapodial bears all the weight rhino. 3rd metapodial long similar in length to other limb bones. Other toes are reduced to slivers of bones that fuse with the 3rd metapodial, or are lost. Paraxonic third and fourth metapodials, bears most of the weight still have 2 separate condyles at the separate distal ends these features are adaptations for stride and speed as prey animals.
