Not smart enough to be raw foodists, or to out-compete modern humans.
Well, I suspect they must have been partially raw like the Inuit. Also, greater intelligence does NOT necessarily imply a greater chance of survival. I only have to look at family and acquaintances around me to see this. The really intelligent people I know virtually all have no children, with a very few having at most two, if that. The stupid relatives and acquaintances I know commonly have 2 or 3 children per couple. In the case of the Neanderthals, they lived in much harsher climates than early modern humans, which was another factor in their demise. One other possibility mentioned by archaeologists is that the arrival of early modern humans caused mass epidemics among the Neanderthals which wiped them out, and no amount of intelligence at that time could solve that problem.
