ANT-2230 Lecture Notes - Lecture 2: Orgasm, Adaptationism, Punctuated Equilibrium
19 Aug 2016
School
Department
Course
Professor
Document Summary
Misconceptions of evolutionary theory: bigger is better, misconception: natural selection will always lead to bigger structures like larger brains, truth: bigger is not better. Bigger brains require lots of energy to grow and maintain; they use 28% of our metabolic rate even if they aren"t being actively used. Intelligence is also not necessary for, or related to, reproduction (which is the meat of evolution). Brain size had been steadily increasing, and became. There was an increase in prenatal brain size; previously, postnatal development was enough for the brain to grow to the adult size. The adult brain size in humans is so large that the fetal head, at the time of birth, is only half a centimeter smaller than the maternal pelvic canal. Compare the process of a cat birth vs. a human birth. In such a birth, the human infant has to maneuver their own way out of the body.
