Genetic drift is a change in the gene pool due to chance. Genetic drift increases as the population decreases. What accounts for this relationship?
Compare and contrast microevolution and macroevolution.
Microevolution is changes in the frequency of genes in a gene pool. According to this definition what is the smallest biological unit that can evolve?
In his talk, Paul Andersen explains the five causes of microevolution. Research one example for each cause in the human population.
Use the following population simulator to simulate microevolution:
www.radford.edu/~rsheehy/Gen_flash/popgen/
Run the simulation using the default settings. Note the change in gene frequencies due to chance. Reset the simulation and increase the population size to 200. Run the simulation again and note the change in gene frequencies due to chance. Reset the simulation and increase the population size to 1000. Run the simulation again and note the change in gene frequencies due to chance. How does the size of a population affect the gene frequencies over time?
Use the simulator to study the effects of migration, mutation rate and bottlenecks on gene frequencies over time.
Learn more about evolution from the following resources.
What is microevolution? evolution.berkeley.edu/evolibrary/article/evoscales_02
PBS – Evolution resources for teachers and students www.pbs.org/wgbh/evolution/
Biology in Motion Evolution Lab www.biologyinmotion.com/evol/index.html
Examples of Natural Selection – Paul Andersen www.youtube.com/watch?v=S7EhExhXOPQ&feature=plcp
To learn more about Paul Andersen, visit his website.
www.bozemanscience.com