Simply because of luck, we are the first species to have evolved this level of intelligence. There's always a first time for everything, and we just happened to be it. Give evolution some time, like a few million years, and other intelligent species may evolve. There are also some species that could have reached a human level of intelligence before us, but they went extinct before they could achieve it. Some scientists think that certain species of dinosaurs could have become intelligent eventually, if they had not gone extinct 60 million years ago due to the killer asteroid. Another candidate is Neanderthal man, who was a different species from us, who went extinct probably due to climate changes that were adventagious to modern humans and bad for Neanderthals. Among current animals I think the best candidate for evolving human intelligence would be a species of dolphin. But don't hold your breath. Intelligence is not really necessary for survival; most animals get along perfectly well with the intelligence they have. There's not much evolutionary pressure to be intelligent. Our immediate ancestor, homo erectus, spread all over the Old World and was very sucessful, having 75% of our brain size. I don't see how our larger brain has given us any survival advantage over Erectus. Indeed, too much intelligence may be a bad thing, as it has given us the ability to destroy the planet and ourselves.

no, human intelligence is just different, not better, than other animals i think ;)

'cos other animals are tougher. They keep warm without clothes, they're happy hunting or grazing - can't be bothered building supermarkets or houses. They live near their friends / rellies / food so they can't be bothered travelling. They don't need haircuts, manicures, dentists, they don't need to shave... WHAT THE FFFFFFFFFFFFF DID WE DO WRONG??????????????? Oh, that's right. We ate an apple. Maybe they got lucky 'cos they didn't eat the apple!