Nature versus Nurture.....which do you believe?

I would like to use the above recent photograph as a place to start with my question of "Nature versus Nurture."  

These are my two sons (Mark and Bobby, aren't they both so handsome?)  I would like to first point out that they take after their mother and me in different physical ways.  Mark has her hair and skin color and Bobby has mine.  The two of them are different emotionally and verbally.  Mark is animated when he talks, he always has been since his first word.  He is a great story teller! He told a story the other night to the entire family that had us laughing and crying at his theatrics.  Bobby is the strong silent type (Clint Eastwood comes to mind.) When he speaks up everyone listens, he chooses his words carefully!  He is an incredible man of observation.  He should have been a secret agent.

When I look at this picture I can't help but think of my dad.  He babysat my kids with my mom at least once a week for their entire childhood, so they spent plenty of time with him. Of course I spent my entire life around my dad, so his "antics" rubbed off on me or were these traits already in my genetic makeup. Mark is making what I call "The Cheese" face.  Bobby is being very cavalier with giving the photographer "The Bird."  

Now you might think that these are totally "Dave" traits.  You can think that, but I see my dad in both of these things.  Perhaps I got it from him and passed it on--or my kids watched the both of us. My father was never shy about showing his funny side to the kids. As much as I asked him to be more conservative about his behavior around the kids he would just give me his stock answer, "I'm a Senior Citizen, I can do whatever I want!"  Well, how can you argue with that?  If you knew my dad that was just who he was.  

My question is this, would they be like this if they were orphans?

My friend Lora has a 22 year old daughter who has not really spent much time with her father.  He was not a nice man and they did not want to be around him.  What's interesting to me is how many traits the daughter exhibits that are just like her father! If you were to talk to Lora she would tell you it's uncanny. One very simple example is the way her daughter drinks an ice cold beverage. She will make a sucking noise to get a small amount of fluid every time she leans back to imbibe.  It is just like her father.  When Lora watches Delanie drink, it's like watching her ex husband.  How is it that something as simple as that can be passed on without observation(Nature?)

My grandpa lived in St. Louis,  stammered and stuttered when he was a boy.  I was born in 1963, he was born in 1907.  So when I started to stutter in first grade (1968) he was 61 years old. I never heard him stutter! My mom told me that he was picked on by kids (non-Irish) in the neighborhood ( they would surround him like wolves and attack him.  My great grandmother told him to put a rock in each hand  and swing like crazy when attacked.)  Sometimes an emotional event as traumatic as that can start a young man on the road to verbal roadblocks. My grandfather was a very eloquent speaker when I knew him.  

I stuttered when I was beaten and afraid at St. Catherines Military School.  Obviously "Nature" took over with this.  Somewhere in my DNA is a gene that expresses verbal dysfunction under duress.

My little six year old cousin Jackson was eating breakfast next to his grandpa (Cousin Ricky.)   Julie and I were watching and observing how their facial muscles were exactly the same in motion during mastication.  Now that's hard to copy (nature.) 

Giving "The Bird" and giving "The Cheese" Nature or Nurture?

I wonder how much choice we really have?