1 / 20

Evolution

Evolution. Chapters 15 - 17. 15. Evolution is both Factual and the basis of broader theory. What does this mean? What are some factual examples of evolution? What are some problems we apply evolutionary theory to solve?. Charles Darwin. 15.

alida
Télécharger la présentation

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. Evolution Chapters 15 - 17

  2. 15 Evolution is both Factual and the basis of broader theory • What does this mean? • What are some factual examples of evolution? • What are some problems we apply evolutionary theory to solve?

  3. Charles Darwin 15 • He wasn’t the first to suggest organisms change, so what was the major contribution? • How did the work of other scientists influence him? • Lamarck? Lyell? Wallace? • What were the “holes” in Darwin’s theory? Who helped fill these?

  4. 15 Mechanisms of Evolution • Starts with variation in the population • How is variation established in a gene pool? • Selection • Artificial vs. Natural? • What effect does this have on variation? • Gene flow • How does it affect allele frequencies in a population?

  5. 15 • Genetic drift • Do populations always evolve for the better? • What is a population bottleneck and how does this lead to the evolution of a population? • How does the Founder effect relate to the effect of a bottleneck?

  6. 15 Mechanisms of Evolution • Sexual Selection • Examples? • Often explains characteristics that seem to have no adaptive value but stick in the population.

  7. Measuring Allele Frequencies 15 • What is the significance of changing allele frequencies? • What is the relationship between allele and genotypic frequencies?

  8. Measuring Allele Frequencies 15 If p equals the frequency of the dominant allele (A) and q equals the frequency of the recessive allele (a), then: • p + q must equal 1. • P2 = frequency of homozygous dom. (AA) • 2pq = frequency of heterozygous (Aa) • q2 = frequency of homozygous rec. (aa) Why? Know how this is derived using probability!

  9. Hardy Weinberg Equilibrium 15 Populations only maintain genetic equilibrium under certain conditions. What are the five requirements for H-W Equilibrium?

  10. 15 Modes of Selection - How do they differ? - When might each occur in a population? - Know examples!

  11. Molecular Evolution 15 • Why don’t all changes in DNA lead to a change in protein? • How does the rate of mutation compare between silent sites, missense sites and pseudogenes? Why is this significant? • What are the conditions for positive and purifying selection?

  12. Heterozygote advantage maintains polymorphic loci 15 • How does this help explain why deleterious mutations may stay in a population? • Examples: cystic fibrosis or sickle cell anemia

  13. Promoting Genomic Changes 15 • What are the disadvantages of sexual reproduction? • So how did it manage to evolve? • Examples of lateral gene transfer? • What are the various outcomes of gene duplication?

  14. 15 Practical applications of Evo. Theory • How is it used for studying protein function? • In vitro evolution- how and why?

  15. 15 Practical applications of Evo. Theory • Agricultural benefits? • Assistance in studying human disease?

  16. 16 Phylogenetic Trees What can they tell us? - nodes? - lineage? Be careful – lots of similar words. Know the nuances of their meaning!!!

  17. 16 Evidence for evolutionary relationships • Homologous traits resulting from divergent evolution? • Are all similar traits evidence of relatedness?

  18. 16 Building phylogenies • What sources of data can be used to build phylogenies? • Do any have benefits over others? • Can we test the accuracy of molecular methods?

  19. 16 Phylogenies compare, but can they also predict? • What practical applications does constructing phylogenies have? • How does the molecular clock assist in mapping evolutionary events?

  20. 16 Phylogeny as the basis for classification • Remember your classification scheme! • How has the Linnaean system been changed over the years?

More Related