Peacocks and Reproductive Isolation

There are three types of Reproductive Isolation; behavioral isolation, temporal isolation, and geographical isolation. All three types can break a species up into two or more species over long periods of time. Although all three can each affect different species, behavioral may be the type of reproductive isolation that affects a population the most.

Each individual organism has its own behaviors, no matter what species it may be. These behaviors are passed on genetically from generation to generation. As they get passed, they change because they are different than the others previous to them. As these behaviors become more and more different, it is possible that the organisms will get to a point where they will no longer mate with each other. This can be for a large variety of different behavioral changes within the species or the interests of or dislikes of the organism or species; or the individual organism. If the behaviors change enough to the point of separation due to the differences in behavior, over generations time, the groups can separate into two or more different species.
This would lead to the inability to mate with the other species even though they were once one species that used to mate together. The gene pools would then be completely different over time from the new species. There could be changes in the color of the species, the sharpness of claws or teeth, the length of their tails, or other unique features that may be present within the species.

One example of behavioral isolation is in peacocks. Peacocks are a beautiful type of bird. Males have large beautiful and colorful feathers whereas the females have more dull brown colored feathers. The females choose their mates based on their interest in the feather color of the males. If the males begin to develop a large amount of one colored feather, the females will begin to choose preferences. They will eventually separate into two species since certain females’ wont mate with certain males. This is behavioral separation and the two different “species” of peacocks (created over many generations) will no longer be able to mate/breed with each other.

Behavioral isolation is very common among many types of animals and many species.

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