CAS AN 234 Lecture 4: lecture notes 1:31:17 - Adaptation (cont.) and Intro to Sexual Selection

• School: Boston University
• Department: Anthropology
• Course: CAS AN 234
• Professor: Carolyn Hodges- Simeon

Document Summary

Last talking about adaptation (structures built by natural selection that aid and increase in reproductive success in the ancestral environment. Two primary ways of nding the function of an adaptation: 1) reverse engineering - gure out parts and how they work together and what kind of job those parts working together can accomplish, assumptions that all features are important and go towards the goal (function) 2) comparative method - comparing humans to other species. The problem of the peacock: the existence of structures or behaviors that have no clear bearing on helping an organism survive, hinders survival (energetically costly to build, conspicuous to predators, mobility hinders) but increases chances of reproduction. Sexual selection builds adaptations that increase mating success: more mates and better mates. Two kinds of sex differences: primary (genitals, xy chromosomes); secondary (size, color, behavior, physiology, products of sexual selection) Secondary sexual characteristics of primate males: coloration, noise, beards, lower voice, increased muscle mass.