For a long time, psychologists have been involved in a debate known as Nature vs. Nurture. This debate looks at how a person develops in relation to their genetics and how they were raised. Many psychologists believe that the way we end up has to be a result of one of the two, either nature or nurture. I, however, believe that it is based on a combination of our genetics and our influences as we are maturing.
On the Nature side of this debate, it is believed that our personality and how we go about our lives is entirely based on our genetic code. Some people believe that sexual orientation is due to genetics, and they point the the Nature side of the debate. Some of the best support for nature are Identical Twin Studies, in which separated twins are reconnected and scientists often find similarities between how their lives have turned out.
On the Nurture side, it is believed that genetics have very little affect on how we turn out, and it is all due to our influences as we grow up. Examples of the Nurture theory include the behavioral experiments of B.F. Skinner. He was able to train pigeons to dance, and play tennis, which should not be possible according to the Nature theory. Another example of the Nurture theory is how an individuals sense of humor is formed by the environment around them, and not their genes.