1 / 9

The Genetics of Evolution

The Genetics of Evolution. What is the relationship between the genes of a population and evolution?. Standards:. BI7. a. Students know why natural selection acts on the phenotype rather than the genotype of an organism.

kali
Download Presentation

The Genetics of Evolution

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Genetics of Evolution What is the relationship between the genes of a population and evolution?

  2. Standards: • BI7. a. Students know why natural selection acts on the phenotype rather than the genotype • of an organism. • BI7. c. Students know new mutations are constantly being generated in a gene pool. • BI8. c. Students know the effects of genetic drift on the diversity of organisms in a population.

  3. Objectives: SWBAT… • Explain thatnew mutations are constantly being generated in a gene pool, and this can cause evolution. • Understandthe decrease in genetic diversity in a population caused by genetic drift.

  4. Where does the genetic variation come from for evolution? • Gene pool-combined alleles for all the individuals in a population • Genetic variation is stored in the gene pool • Alleles-different forms of trait (eye color) • Allele frequency-measure of how common an allele is in a population

  5. What are the five factors that can cause evolution? • Genetic drift-allele frequencies can change due to chance alone • Gene flow-the movement of alleles from one population to another, changes allele frequencies in each pop. • Mutation-can form new alleles, creates genetic variation needed for evolution • Sexual selection-certain traits may improve mating success • Natural selection-certain traits can help survival, these traits increase in frequency

  6. What is gene flow? • Gene flow-movement of alleles from one population to another • Occurs when individuals of species move between populations • Increases genetic variation

  7. What processes allow genetic drift to take place? • Genetic drift-changes in allele frequency due to chance, decreases genetic diversity • Bottleneck effect-GD that occurs after an event greatly reduces the size of the population. (overhunting) • Founder effect-GD that occurs after a small number of individuals colonize a new area. (islands)

  8. Genetic Drift Bottleneck Effect Polydactyl (Amish)

  9. Summary Questions • What is the gene pool of a population? • Name two genetic factors that can cause evolution. • Does genetic drift decrease or increase genetic diversity? • What is the relationship between the genes of a population and evolution?

More Related