Scientists find brain evolution gene

Large brains might be selected for because of the advantages to being able to keep larger social groups (the larger the group the easier the mating and the better the fighting force). As many evcers are aware, in primates brain size and social group size have an interesting correlation.What I find more interesting than HAR1 is ASPM (something a little more scientific can be found here) which may be evolving even now. I would be interested to learn when any studies about how this mutation effects social sizes or other cognitive functions.