To Sir, with Love: How To Get More Women Involved in Open Source (O'ReillyNet)

The "skin size" has nothing to do with the number of neurons there. If you draw a human and reshape it so that the sensitivity neurons have the same area density, you'll see something with large hands and testicles, and almost no back at all. The number of neurons per area depend on how important that part of the body is for sensing things, not how big you are. There are a number of things which compensate each other. E.g. a small animal can react quickly and move its legs fast. It needs short neural connections for that, and due to the low dead time of its body, it needs to operate fast to balance things out. Large animals however have high dead times and long "wires", so they can't react so fast, and also they don't have to. An elephant moves in slow motion. You don't need a better brain for that - you can run your brain slower. Elephants use their large brains to remember a lot, not to be artistic.

IMHO the point of the brain size/body volume equation was because someone figured out that we don't have the largest brain on the planet, but think we are the most intelligent life form. So there comes the brain size/body volume equation, which puts us in advantage of elephants, whales, and especially fat Americans (for which then somebody invented the fat-free encephalization quotient ;-). However, it also puts mice as equal to us, and small birds far ahead.