BIO 1130 Lecture Notes - Lecture 12: Deciduous Teeth, Heterodont, Phanerozoic

• School: University of Ottawa
• Department: Biology
• Course: BIO 1130
• Professor: Jon Houseman

Document Summary

Could use the feathers on their front limbs as a way to feed. Had arms with digits and feathers: sweep arms in the ear and catch insects, one time bird sweeps down and realizes it can fly. Ground up hypothesis: birds lived in tree and used feathers to glide down and eat insects. Lighter than skin but can generate lift against air. Skeleton is much smaller, reducing bones, no tail. Muscles attach to the sternum (breast bone) Two muscles: one to lift (small) and one to pull wing down (big) Erector muscle to make hairs go up and down. Dentition to match watch jaws have to do: canine for meat, molars for grinding. We must produce 2 sets of teeth because jaw is growing. Oviparous: monotremes still lay eggs, young lick secretions from skin glands. Embryo must crawl out quickly and live in pouch: eutherians. We will (cid:374)ot (cid:271)e (cid:272)o(cid:374)ta(cid:373)i(cid:374)ati(cid:374)g (cid:373)others" (cid:271)lood. Can be short few weeks (mice)