Lecture 3 ANTH 170c1 Outline of Last Lecture I Adaptation II Three categories of natural selection III What are the 3 necessary and sufficient conditions for natural selection III Stabilizing selection IV Directional selection V Disruptive selection VI Ways of describing traits Outline of Current Lecture I How to determine when traits evolved II Ways of describing traits A Homology Homologous traits III Similar traits not acquired from a LCA A Analogy Analogous traits IV Ways of describing traits V Primates VI Lemurs Island of madagascar Current Lecture Title Traits I How to determine when traits evolved A First see if the trait appears in close relatives 1 If so its likely that a last common ancestor had this trait and the trait II Ways of describing traits A Homology homologous a trait that is similar in 2 or mote species due to presesnce of the trait in a common ancestor Ex wolfs cows III Similar traits not acquired from a LCA A Analogy analogous traits similarities between traits of two different organisms that is due to convergent evolution not common decent Ex birds bats IV Ways of describing traits A Derived traits a trait not present in a common ancestor a trait that is new to a lineage V Primates A There are lots of variation in primates but similar body sizes tend to live in single male groups B We share a common ancestor C Primates characteristics 1 Grasping hands and feet with nails instead of claws 2 Hind limb driven locomotion 3 Reduced olfaction and enhanced vision 4 Forward facing eyes 5 Small litters 6 Large brains long lifespans 7 Behavioral flexibility IV Lemurs Island of madagascar A Many lemurs display female dominance which is rare in other primates B 2 types Galagos and slow lorises These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute