Limits to Brains
The difference between smart and average is the speed of neurons and the connectedness of different brain areas. It sounds like that the human brain has reached its best performance as can be produced naturally. This is similar to intelligence in spiders; the brain of a spider is formed around its throat with a bigger brain making the throat so small that the spider can only ingest liquids like blood.
Humans are good at making tools. The early tools were extensions of the body, to increase reach, increase power and to make better tools. Language and writing have been extensions to the mind, to document the past and to explain the world. Combining extensions to the body and mind has given us the high technology we have today.
Given this trend, humans may find a way to overcome the limitations of the brain. It is possible that a series of events can break down our ability to maintain technology and lose the knowledge to make high tech tools. It should be interesting to see how far we can go with what brains we have and the extensions to ourselves.
