Unit 7 Notes: Evolution, Sex, Misconceptions
(1) Vocabulary: Evolution The change in the types of traits that show up in a population over time. Natural Selection The survival of better adapted organisms. Adaptation A trait that increases an organism fitness. Fitness The ability to survive AND reproduce. Species Distinct organisms which will not naturally reproduce together.
(2)Why is sex important to evolution? Sex allows a successful organism to pass their “fit traits” on to future generations, and strengthen the success of the population. Think If successful organisms did not reproduce, would a population survive? No.
(3) What other events can drive evolution? Change to the environment / resources. Migration When organisms with different traits move into a new population and reproduce. Geographic Isolation When barriers like land or water separate a population into groups that no longer reproduce together. Genetic Drift The random “removal” or certain organisms, and their traits, from the population.
(4) Evolution is not… Evolution is not: The extinction of all “old” organisms, and only the survival of “new” and modern day organisms. The changing a population to be more perfect. A linear progression. Evolution IS the change in a population because only some are able to stay alive, and because only some are able to find mates and reproduce.