Lab: Sickle-Cell Alleles
An interactive simulation of the classic malaria and sickle-cell anemia system is used to explore natural selection and genetic drift. Students examine African villages with different malaria death rates. First they use the Hardy-Weinberg equation to calculate the expected proportion of sickle-cell carriers from HbS and HbA allele frequencies. Then they examine how the allele frequencies change with changes in malaria risk and with different "founder" scenarios. Finally they explore genetic drift without selection by looking at different-sized villages where both diseases have been cured. An optional advanced section allows independent exploration of evolutionary forces using a basic population genetics model with adjustable parameters for selection strength, immigration rate, and population size. This is one of our most popular labs for introductory biology courses.
View sample screen
Key Concepts: Genetic Drift; Hardy-Weinberg Equation; Natural Selection
Courses: Evolution; Hardy-Weinberg; Intro Bio: Eco/Evo/Genetics; Population Genetics
"We used the Sickle-Cell EcoBeaker™ lab with all 1100 freshman enrolled in our majors biology course in the fall of 2003. The results truly impressed me — I felt like the students had a much stronger grasp of Hardy-Weinberg theory as a result of this interactive exercise and exam scores went up as well. "
Dr. Linda Walters, Central Florida University, Majors Introductory Biology
"I had great success using your EcoBeaker™ labs, Keystone Predator and Sickle-Cell Alleles, in my BIO102 General Biology II class (4 lab sections, 96 students) this spring semester. "
Dr. Daniel Vogt, Plattsburgh State University, General Biology
"This is just a quick email to let you know that the Sickle-cell lab went very well last week!! The TAs thought it went very well and the feedback from number of students I spoke to was also very positive. ...I was very pleased to be able to introduce this topic into a compulsory course here at the Technion in a Faculty that has major emphasis on molecular biology and less on populations, ecology and evolution."
Dr. Debbie Lindell, Technion, Israel
+ Add to collection