Posted: Nov 24, 2010 10:15 am
jez9999 wrote:I always find it curious that creationists always seem to use the eye as an argument against evolution. 'How could something so complex evolve?' We can explain that pretty well, and their argument is very weak.
If they had picked the human brain, however, they'd be harder to refute. The human brain does seem to stand out to me as truly exceptional and unique. Evolution doesn't feel like enough to explain it. After all, other complex adaptations are evolved simultaneously by lots of different species, because they are useful to living... speed, strength, swimming, flying, sight, hearing, etc. But a human level of intelligence, far above instinct? No other species on Earth has EVER developed anything like it. That's not meant to happen in evolution; although I can accept that some fortuitous circumstances allowed humans to develop tools with our hands thanks to bipedalism, you'd still expect a few other species to have developed truly advanced intelligence if it were an evolutionary benefit. The dinosaurs had millions of years and their intelligence level was frankly pathetic. It's almost as if aliens visited earth 500,000 years ago, and implanted some special process in a certain group of apes that would cause them to rapidly evolve a high level of intelligence way beyond what had gone before in the last billion years.
Our brains (as I understand it) are an enormous evolutionary gamble. They are sensitive to temperature and to impact, they are expensive to run, often faulty and unreliable, they make birth difficult and often deadly. They also require adaptions elsewhere around the body, for example, without manual dexterity or a voice box much of a human-type brain would be useless. I am not surprised it was only ever successful in one instance, frankly our success is so far extremely short-lived. Let's see if we survive another 20 million years or so.