I was watching a documentary about dinosaurs. It said the largest dinosaur had a brain the size of a walnut because it only needed to do simple things. This got me thinking. Humans have large brains. This would suggest evolution has made th ebrain bigger through requirement of use. However the things we use it for have increased over the last few thousand years. The brain has been the same size for millions of years. This would mean either our brains should be getting bigger to deal with the increase of usage e.g. language, mathmatics, using tools, engineering. However this is not the case the brain is the same size as it was before these things were required. That would indicate the evolution of the brain is not as a result of the requirements it has set or that the expected requirements were anticipated and the brain was designed to be capable of these requirements before it actually did them. This suggested the brain was designed to be able to function in a certain way outside of evolutionary enviornments. Any thoughts.