origin of body-language

Sometimes when mum watches me and Oscar she she can't help but wonder where the way we move our body or body parts while playing or speaking, comes from. And she asks her self what the origin of our body-languagemay be ?

• Physical: When I'm tired I rub my eyes, and so does mum actually, and Oscar and dad. Nobody taught us to do it, we just do it, and when I do it, my parents know it's time to put me to bed. I'm sure the reason why we do this is physical, although I have no idea what exactly it is, maybe it's because we tend to fix our eyes when we get tired, so they become more dry, and so we have to rub them to get them moist again...or something. Another example is how we stick out our bump and lean forward the upper part of our body when we are about to pee or poop in our pants -a great signal for mum that she should bring Oscar to his potty in order to avoid a small accident.

• Imitation: When Oscar particularly likes his food he will point his index-finger to his cheek and pretend he is fixing a screw into it. In italian body-language this means: MMMmmmm very good food! There is nothing physical about this movement, and I have no idea what's the origin of it is, but for sure Oscar learnt this by imitation, from dad, from the other kids in kindergarten or somewhere else. A wonderful way to enrich the spoken language I would say!
  

• Natural: If mum ever wondered why we nod our head when we say yes and why we shake it when we say no -she can now stop wondering. The origin is so primitive and natural that it surprised even mum when she realized it! Have you ever tried to feed a baby that doesn't want to be fed? Try to feed me the last few spoons of my pappa when I've just had enough. I'm too young to say noooo (although I'm quite getting it) and therefore all I can do is avoiding to get another spoonful in my mouth. And how do I do that? If I bend forward (nod my head) the food will end up in my eyes (I've tried that and don't recommend it). But if I shake it to the sides at most it will leave a trail of food on my cheeks (just don't shake it so much that it will end in your ears that are difficult to clean).

• Invention: Gestures of all types come in very handy for those who don't yet master the speaking skill perfectly and much of them have to be invented along the way -sometimes in a desperate attempt to be understood. Many of those are used only once, but the more clever ones might find their way into common gestures. I guess that this is actually the real origin of most of the gestures we learn by imitation.
  

• Genetics: When Oscar has finished his food he will say FINISHED and then he will raise his arms (elbows bent) a little bit in the air and shake the hands around the wrist. Now where does that come from? I find it hard to believe that there is a physical reason for this (but if someone does I'd like to hear about it). No one around him does this, so it's unlikely to be imitation, and I don't think nature teaches us that this is the best way to signal that we've finished the food. Did he invent the gesture? We can't exclude it, but then it would be a strange coincidence! Mum was actually quite startled when Oscar did this for the first time, not because it seems such a ridiculous gesture to do, but because she had actually seen it before. Afi Lalli in Iceland does just the same thing. But had Oscar seen it? Maybe so, but he would have been very little, and although he does pay a lot of attention to things around him, it is unlikely that he'd picked up this unusual gesture when he was just 1 years old. So the only plausible explanation is genetics!! Not only has Oscar inherited much of granpa's look but also some of his gestures. Maybe somewhere on the long arm of chromosome 1 there is a gene encoding for this trait!!