B.7(F) Supporting
Genetic Drift
Genetic drift occurs when individuals may, just by random chance, survive and reproduce more often than other individuals. Which individuals survive is totally up to chance, not related to adaptions or natural selection. Genetic drift has the largest impact on small populations.
Gene Flow
Gene flow occurs when individuals carry their genetic material from one population to another. This will introduce new alleles into a population through recombination (sexual reproduction).
Mutation
Mutation cause evolution to occur when a new trait is introduced into a population. A mutation could cause two parents who are bright green to have an offspring with brown coloration.
Recombination (Gene Shuffling)
Genetic recombination, sometimes referred to as gene shuffling, is the exchange of genetic material between different organisms which leads to production of offspring with combinations of traits that differ from those found in either parent. This can lead to offspring with adaptations, different from the parents, that can potentially increase fitness which they could pass onto their offspring.
Activity
Trace your hand on a piece of paper. Watch the video over the Five Fingers of Evolution. As you watch, write on your traced hand each mechanism of evolution and a brief description of how each mechanism is responsible for causing evolution.
Check Your Understanding
1. What are the mechanisms of evolution?
2. How does recombination of genetic material lead to evolution?
3. Give an example of genetic drift and how it leads to evolution?
4. Describe how skin color is an example of gene flow in the human population?
Practice answering the following STAAR questions
