I got together with a few friends the other day. The conversation tangentially bumped into the idea of genetics. What is inherited? You are on pretty safe terrain when you look at a child, and say he has his father's chin, or his mother's eyes. But did that attitude come from the gene cocktail, or did it come from environment? Is curiosity inherited? can you be a smart-ass by birth?
How much of what we are is determined by birth? I look at my parents and pray that environment holds most of the cards. I look at my child and see one inherited characteristic after another.
When I was in college, I took a course that linked biology and behavior. I was outraged by the very idea that anything about my actions was determined by wiring. I had FREE WILL. I was no mere combination of chemicals -- I was a thinking rational being. Now, I am older, and have the experience to see that yes, there are some things that can't be explained any other way -- wiring does have a huge part in what we are, and how we act. It isn't everything, and I do think it can be battled with on a conscious level, but to deny it is there, is to move through life with blinders on.
I think we need to understand how we are wired. In a way, I think having a kid gives you a glimpse into your own "operating system". When I see certain behaviours that crop up in my son, I have this "a-ha" moment. The oh-my-god, it's genetic kind of moment. And I understand myself a little better, as I learn to understand him.