One of the methods used by behavioral geneticists is
selective breeding. Selective breeding often involves selecting animals that are very different on one measure of behavior. For instance, if scientists take 20 rats and test how quickly they can solve a maze, chances are that they will get some variability in the speed with which the rats can solve the maze. Scientists would take the two fastest animals and the two slowest animals and breed them together. They would continue to do this over 20 generations, until they had a group of animals that solved the maze very rapidly and a group of animals that solved the maze very slowly. They are then able to examine potential differences in their brains and behaviors that contribute to maze solving. Scientifically, selectively bred animals allow for investigations into what contributes to specific characteristics in animals, or how specific characteristics in animals may interact with behavior.
A form of selective breeding is used by dog breeders to select for choice characteristics that buyers are looking for in dogs. Dogs that are the best representatives of their breed are bred together so that they are more competitive in shows that give awards for breed characteristics.
What are other areas that you think selective breeding may be used for other reasons? (e.g., to maintain genetic variability in a dying species, to breed hens to lay larger eggs, to breed cows to make more milk, and to breed faster race horses).
