15.2 PDQ

1. Name and define 3 processes that affect the genetic makeup of populations over time Gene flow – exchange of genes between populations due to migration Genetic Drift – change in gene frequencies from generation to generation due to random processes Non-random mating – selection of mates on basis of traits Mutation – change in DNA Selection – choosing preferential phenotypes

2. Explain, “natural selection acts on individuals, but populations evolve” Changes that occur are developmental in a single organism over the course of a life cycle. After breeding  populations will evolve

4. What is the difference between natural selection and adaptation? Difference in fitness among organisms Enhances the fitness of the organism

5. What is the raw material on which mechanisms of evolution act upon? variation

6. What does it mean to say a population evolves? It genetically changes over time

7. Why is genetic drift more apparent in small populations? Because each individual’s genes represent a large fraction of the gene pool

8. What is the net affect of a population bottleneck? Loss of genetic variation

9. Describe founder’s effect Loss of genetic variation that occurs when a new population is established

10.Define sexual selection Preference by 1 sex for certain characteristics