BIOL 305 Lecture Notes - Cloaca, Heterodont, Hypsodont
16 Apr 2014
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Document Summary
Cynodontia: sister group of modern mammals: small carnivores, have very similar teeth to modern mammals, very strong jaw due to muscle attachment by through the huge fenestra and a crest at the top of the skull, posture is mammalian, endothermy presence: we know this because. Often when these animals feed on herbs, they get sand on the teeth and their ever growing teeth are worn down: compression teeth: for crushing, teeth can be used for tusks: the teeth that are modified to tusks are not always the same ones (can be incisors or canines depending on the species) Mix of primitive and very complex traits: lay eggs, no distinct mammary gland (feed on milk produced on a patch of skin, no nipple to suckle), have a single ventral orifice connected to the cloaca, have a middle ear, fur, lactation, single dentary jaw bone, eg.
