It's common to try to explain things as either due to nature OR nurture. Or, at best, we say: some percentage of the variation in outcome is due to genes, and some percentage is due to the environment. It's important to remember, though, that outcomes can be a complex interaction between the two. Consider this: Our genetically-influenced traits impact what environments we seek out and find ourselves in. For instance, risk-taking seems to have moderate heritability, and it in...