ANTC99H3 Lecture Notes - Lecture 6: Proceedings Of The National Academy Of Sciences Of The United States Of America, Herbivore, Large Treeshrew
Document Summary
Euprimates: modern primates, and fossil primates that have the characteristic features of modern primates = primates. Plesiadapiforms: extinct stem primates, which lack some features characteristic of modern primates. Earliest primates evolved during either the cretaceous period or paleocene. *four euprimate characteristics: improvements to the visual system (postorbital bar, conversion of orbits, grasping extremities (nails instead of claws, long digits, leaping characteristics (long hindlimbs, low-crowned molar teeth with bunodont cusps and broad talonid basins (fruit eating) Dermoptera and scandentia are grouped into the same group with euprimates eurchonta. Dermoptera and scandentia are thought to be the closest relatives to primates. However the toothcomb differ greatly between the two. Dermoptera tooth comb"s incisors have many comb like structures. Phalangeal properties is related to having webbing between the fingers for gliding (palagium gliding membrane) At first they were grouped as primates but the similar features were then proven to be due to convergence. Ptilocercus is the best living common ancestor of primates.