Less than half the world’s adults can digest milk. Geneticists working in East Africa have discovered a gene mutation that enables this trait in certain adults. There are populations in Europe with similar, but not identical genetic mutations that enable them to digest milk. The finding is an example of how a cultural innovation that arises in multiple locations across the globe, in this case raising cattle, can cause unrelated people in different geographic locations to evolve a similar trait.
Assign a small group of students to do further research on the link below and present a brief report on the lactose tolerance mutation to the class.
University of Maryland: UMd-Led Team Discovers Gene Mutation for Milk Tolerance in Africans
The report should answer these questions:
- What is lactose intolerance?
- What causes some East Africans to be lactose tolerant?
- How and when do geneticists believe this mutation occurred?
After the presentation, allow the group time to answer any questions the class has.