Quote Originally Posted by MissElizabeth87 View Post
Bigger brain does not mean smarter. Human beings only use about 3 percent of their brain anyways, and this number actually goes DOWN as the brain increases in size, for the most part. (Sidenote: autistic children and children with certain other neural disorders actually use more of their brain. Maybe they are really more intelligent than we are). A child CAN be smarter and have a bigger brain, but a more intelligent child can actually have a smaller than normal brain. Intelligence is in no way linked to brain size. At least, not by any credited studies. Aside from that, children with a number of neural genetic disorders actually have larger brains than normal... most of them are considered "mentally retarded", which would mean they are not, in a conventional sense, considered intelligent.
Well actually brain size and intelligence are linked. Or rather how big the brain size is in proportion to the rest of the body. What I wrote was, that there's a ceiling where our body "design" can't handle further increases. Which is if I understand correctly is what you're saying to. The selected genes promoting further proportional growth just aren't helpful any more. Because that's how evolution works. It's a bit like having a city but with the infrastructure of a village. On the whole, you'd be better off staying the size of a village. What might happen is that among autists a mutation might occur which makes them a new super intelligent type of human. All perfectly in line with evolution. But that's pure speculation. It might simply be another dead end.