1 / 13

Disruption of Genetic Equilibrium

Disruption of Genetic Equilibrium. Chapter 16.2. Evolution - the change in a population’s allele or genotype frequencies over generations Evolution is caused by: Mutations Gene Flow Genetic Drift Nonrandom Mating Natural Selection. Mutations.

teague
Download Presentation

Disruption of Genetic Equilibrium

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. Disruptionof Genetic Equilibrium Chapter 16.2

  2. Evolution- the change in a population’s allele or genotype frequencies over generations Evolution is caused by: • Mutations • Gene Flow • Genetic Drift • Nonrandom Mating • Natural Selection

  3. Mutations • Mutations occur when an organism is exposed to mutation-causing agents such as radiation and chemicals • Mutations produce completely new alleles for traits • However, mutations can be beneficial

  4. Gene Flow • Gene Flow- process of genes moving from one population to another • The constant flow of genes is caused by immigration and emigration

  5. African Baboon Troop

  6. Genetic Drift • Genetic Drift- phenomenon by which allele frequencies change as a result of random events • In small populations, one change can result in big disruptions • In large populations, a change is less effective • *Thought to be another possible reason for the evolution of new species

  7. Nonrandom Mating • Because of geographic location, many organisms end up mating with relatives -This can amplify certain traits, and result in disorders in offspring • Other organisms mate based upon similar traits, called assortativematingtive mating • Sexual selection is when females choose a mate based on certain traits. The better the traits, the higher chance of survival.

  8. Natural Selection – Stabilizing Selection • Individuals with the average form of a trait have the highest fitness • The average is ideal • Ex. Lizards

  9. Natural Selection- Disruptive Selection • Individuals with either extreme variables of a trait have greater fitness than individuals with the average form of trait • Ex. Sea shells

  10. Natural Selection- Directional Selection • Individuals that display a more extreme form of a trait have greater fitness than individuals with an average form of the trait • Ex. Anteaters

More Related