BIOLOGY 1M03 Lecture Notes - Lecture 6: Extinction Event, Motility, Teleost
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4 general strategies: 1) pheneic (distance) Have info from individuals & calculate distance matrix between. Ex proporion of nucleoides difer between individuals. Computer uses algorithm generally by computer to build tree that clusters together more similar, separate more diferent: 2) cladisic (max parsimony) Approach to inferring focusing on synapomorphies (shared derived characters) Synapomorphy is novel trait that clade has that all others outside clade lack. Ex in mammals: lactate, hair, sweat glands monotremes they lay eggs & then breasfeed through sweat glands. But in: 3) max likelihood, 4) bayesian. For this course we will learn 1/2, but in real life more likely to use 3/4. Homology: similariies are inherited from a common ancestor: more similar between diferent species than within spieces. Homoplasy: traits are similar for reasons other than common ancestry: can happen bc natural selecion favors due to habitat/lifestyle. Convergent evoluion: natural selecion favors similar soluion to problems posed by similar way of life: common cause of homoplasy.