Evolution 101

Evolution 101

1. Mechanisms:The Process of Evolution

   1. Mutation

      1. Mutations are random.

         1. If mutation is helpful, then the organism is more likely to survive and pass it on
         2. Not all mutations matter to evolution

      2. Causes of mutation

         1. DNA fails to copy accurately
         2. External influences, such as radiation, create mutations

2. Gene Flow

   1. Migration from one location to another
   2. Long-term geological event that causes separation of populations

3. Sexual Reproduction

   1. Genetic shuffling

      1. 50% from mother,50% from father
      2. Recessive Genes can be passed on and expressed in the offspring

4. Development of Organisms

   1. Process by which the genotype (genetic makeup) is expressed as a phenotype (trait)
   2. Environmental conditions select the traits that help ensure survival

5. Genetic Drift

   1. Pure chance that some organisms are killed or don’t survive

6. Natural Selection

   1. There is a variation of traits

      1. A wide variety is needed

   2. There is differential reproduction

      1. Not all organisms reproduce

   3. This is heredity

      1. Organisms pass on traits, both dominant and recessive

   4. End result-Survival of the fittest

      1. If the trait gives an advantage to the organism, that organism is more likely to survive and reproduce