Fact 1: Gene flow occurs when individuals move into or out of a population.

Fact 2: Gene flow tends to decrease differentiation.

Given the two facts above, answer the question "What tends to occur when individuals move into or out of a population?" with the following options: 
- competing for resources
 - extinction
 - matter is destroyed
 - metabolic reaction
 - rapid exponential growth
 - seed dispersal
 - decreased differentiation
 - permineralization


 

       decreased differentiation  