phenotype/allele loss when a small founder population is established from a larger source population. Students conclude that the incidence Discussion 4: Return to of HD in Afrikaners is not adaptive, as example, tie in results from there is no increased incidence of this M&Ms activity, show full graph disease in native South Africans. Instead, with incidence of HD in native this is an example of random genetic drift. South Africans. At this point, the term effect” is “founder introduced. Post-tidbit assessment (Outcomes 3,4,5,6,7,8): Students are exposed to Activities after class Students can understand how the concept of drift through Homework assignment adjusting the parameters of drift (starting action (collecting data in class, simulation program population size) and selection (fitness manipulating variables during differences between alleles) impact the Next class: Discussion of simulations and writing evolution of population homework (summarizing their answers Students conclude that multiple when responding to the Next class: Case study: biological scenarios can result in small homework questions). Conservation genetics of Cape population sizes that are strongly affected Reading could also be buffalo. The concept of a by drift. accommodated by bottleneck is introduced. incorporating a post-unit reading of the textbook or a foundational paper, such as Dobzhansky and Pavlovsky (1957) Sample Presentation Plan (detailed schedule with approximate timing for unit) Session 1
Discussion 4: Return to example, tie in results from M&Ms activity, show full graph with incidence of HD in native South Africans. At this point, the term “founder effect” is introduced. Activities after class Homework assignment simulation program Next class: Discussion of homework Next class: Case study: Conservation genetics of Cape buffalo. The concept of a bottleneck is introduced. phenotype/allele loss when a small founder population is established from a larger source population. Students conclude that the incidence of HD in Afrikaners is not adaptive, as there is no increased incidence of this disease in native South Africans. Instead, this is an example of random genetic drift. Post-tidbit assessment (Outcomes 3,4,5,6,7,8): Students can understand how adjusting the parameters of drift (starting population size) and selection (fitness differences between alleles) impact the evolution of population Students conclude that multiple biological scenarios can result in small population sizes that are strongly affected by drift. Students are exposed to the concept of drift through action (collecting data in class, manipulating variables during simulations and writing (summarizing their answers when responding to the homework questions). Reading could also be accommodated by incorporating a post-unit reading of the textbook or a foundational paper, such as Dobzhansky and Pavlovsky (1957) Sample Presentation Plan (detailed schedule with approximate timing for unit) Session 1
understanding_the_mechanisms_of_evolution_genetic_drift_tidbit_framework_midwest_2013_0_1.docx