PSYC 3100 Lecture Notes - Lecture 2: Natural Selection, Phylogenetic Tree, Natural Disaster

• School: University of Guelph
• Department: Psychology
• Course: PSYC 3100
• Professor: Pat Barclay

Document Summary

A phylogenetic tree is similar to a family tree however the direction of time is opposite. Humans are not descended from chimps; they are both descended from a common ancestor of gorillas. When compared to the family tree, chimps are our cousins. Definition of evolution & major mechanisms of change. Change in gene frequency that can result in change in phenotype size, shape, development, behavior: genotype: genetic makeup of an organism, phenotype: an organism"s observable characteristics. Genotype x environment (interact to produce) > phenotype. Non-random survival of random changes; acts on individuals but changes the population. Occurs when at least three conditions are met: competition + heritable variation + differential reproduction. There are not enough resources once carrying capacity is met, therefore there is competition to survive. Heritable variation: offspring tend to resemble parents; variance can be passed to offspring. Differential reproduction: some individuals reproduce more than others (they survive to reproductive age, find mates more easily etc. )