Question

Which of the following best represents an example of gene flow?

• A. A tsunami wipes out all but a few members of a sea turtle population that inhabits a beach.
• B. A group of polar bears migrates from the ice habitat where they live to a nearby forest, where they interbreed with the brown bears.
• C. A large population of prairie chickens is reduced to small numbers by a virus.
• D. A small population of white rhinos is reduced to fewer than a dozen individuals by hunters.
• E. A population of mosquitos becomes resistant to pesticides used to control their numbers.

Answer 1

The correct option is B A group of polar bears migrates from the ice habitat where they live to a nearby forest, where they interbreed with the brown bears.

• Gene flow is the transfer of genetic material from one population to another.
• If the rate of gene flow is high enough, then two populations are considered to have equivalent genetic diversity and therefore effectively be a single population.
• Gene flow can take place between two populations of the same species through migration and is mediated by reproduction and vertical gene transfer from parent to offspring.
• So, the correct answer is "A group of polar bears migrates from the ice floes where they live to the nearby forest, where they interbreed with the brown bears there".