Dunbar's Number - The Social Cortex

Dunbar's number is the idea that humans can hold around a hundred and 50 distinct social relationships in mind at any one time. For in primates, the greater the new cortex, the larger the average social group size. apes have a slightly lower group size per neo cortex size than monkeys. It seems there's likely something special about dunbar's number being violated. After all, much of the upper neolithic revolution is occurring when groups of humans in the few hundreds are getting together seasonally into much larger groups.