BIOL108 Lecture Notes - Lecture 35: Treeshrew, Eutheria, Cloaca

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL108
• Professor: Lien Luong

Document Summary

Nourish young via placenta until very well-developed. Disadvantages? requires a long gestation period; energetically expensive for the mother therefore limits the size of mammals- the biggest mammal on earth is an elephant then suckle young with milk. # of nipples indicative of typical # of offspring born at a time. Have separate urinary & anal openings (no cloaca) Order primates (lorises, lemurs, monkeys, apes, humans) Characteristics: thumb & toe widely separated from other digits; allows grasping flat nails rather than narrow claws on some digits large brain & short jaws forward-facing eyes; binocular vision. Evolution of grasping hands with nails limbs with opposable first digits allows for a powerful grip. Hominids lack tails, have relatively large brains includes orangutans, chimpanzees, bonobos, gorillas, humans lemurs, lorises, and bush babies are therefore known as non-anthropoid primates (non-humanlike) South american (new world) & african (old world) groups of monkeys radiated independently. New world monkeys: all arboreal; live primarily in trees.