Link to article: http://genealogy.about.com/cs/geneticgenealogy/a/nature_nurture.htm
While it is clear that physical traits such as eye and hair color are encoded in your genes, the debate still raged since the 13th century whether parts of your personality are also encoded in your genes. The part of this article that I found most interesting was when it referenced studies done on identical and fraternal twins. Whether raised in the same environment, their personalities resembled each others more similarly than did non-twin brothers and sisters. But even when researchers studied twins that had been raised apart from one another, they still found that they closely resembled each other. This seems to suggest that parts of our personalities' are encoded in our genes. It would make sense that humans, like almost all other animals, have instincts encoded in our genes, but scientists have been unable to locate these "behavioral genes" with 100% accuracy. Humans are the only animals that are born without instinctively knowing what kinds of food to eat, which is learned from our parents. On the other side of the debate are the nurture advocates, who believe our personalities are derived from the environment we are raised in. Early psychologist such as John Watson and BF Skinner showed that phobias could be acquired be acquired through conditioning, and pigeons could be taught to dance, fly figure 8 patterns, and even play tennis. If personality was 100% based on genes then identical twins would be the same in all aspects, but many studies have shown that this is not true. Humans, as well as almost all the animals in the animal kingdom, are made to adapt. If presented with a specific environment, humans are going to adapt so that they can be the most successful in it, and their genes determine what kind of adaptations they will make. It is probable that our personalities are determined by a mix of our genes and our environments. Nature AND Nurture.
Additionally, some of you may enjoy this video: http://www.youtube.com/watch?v=81szj1vpEu8