Answer: The high frequency of polydactyly in your professor's ancestry is an example of a genetic drift.
Step-by-step explanation:
A genetic drift is when there is a change in the gene pool. This occurs with a small population of people that live in the same area. This happens by chance and is not something that will always happen in a small community. This can occur with a small population of people over time when the gene pool is too small and the alleles makeup can change over time.
This is also known as the Sewall Wright Effect.