While not discounting that genetic tendencies may exist, supporters of the nurture theory believe they ultimately don't matter - that our behavioral aspects originate only from the environmental factors of our upbringing. Studies on infant and child temperament have revealed the most crucial evidence for nurture theories. For example, American psychologist John Watson demonstrated that the acquisition of a phobia could be explained by classical conditioning. What are your thoughts?
Lecci, L. (2015). Personality. San Diego, CA: Bridgepoint Education.