Mozart had billions of neurons in his brain when he was born. That brain experienced 99.99 % noise at birth (or total synestheisa). How the noise turned into signal - how we all turn noise into signal - is by the connecting of those neurons into pathways and networks. How are those networks created? By hardwiring, induced by the presence of biochemicals and their interfacing with neuronal receptors. These receptors trigger different processes. In the case of endorphins, new connections are made between 'neighbouring' neurons that are firing at the time.

How much endorphins are released in response to stimulii (or are present - heroin is an external molecule that happens to fit into endorphin receptors), depends on DNA, INTERACTING with the networks already in place. Internally produced biochemicals are not limitless in supply - they have to be made. GABA, for instance, (Gamma-aminobutyric acid) powers the inhibitory neurons that regulate the 'excitability' of the mammalian CNS. GABA, a neurotransmitter) is 'manufactured' while you sleep. Sleeplessness or a genetic disruption to GABA manufacturing can lead to movement and anxiety disorders, epilepsy, schizophrenia, and addiction.

This is just one of a thousand examples of how genetic predisposition (OR behaviour like not sleeping) can alter behavioural pathways - temporarily or longterm. I am not trying to ignore the complexity of these biochemical relationships. But....

Learning CANNOT exist without biochemicals. Behaviour CANNOT exist without biochemicals. And thus, I assume, the fact that we individually have' factories' that comparatively are more efficient or less efficient at producing these biochemicals than another individual, gives them some role, yes, even in the Requiem.

Sociobiology is about whether the DNA that produces those factories might be similar enough in closely related members of a group to lead to similar behaviour = group behaviour. Obviously the sensual environment of the group (including the existing culture) would have to be very similar, and the biochemical gender and age differences taken into account. (Puberty being the biggest personality-changing trip most people ever experience). I don't think it is a subject to be dismissed by flippant remarks about Mozart, mon ami ;-)

You can't be me, I'm taken