“For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so much—the wheel, New York, wars and so on—whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man—for precisely the same reasons.” - Douglas Adams
Maybe they were quick to figure out it was a dead end?
Seriously though, isn't one of the issue that regardless of how intelligent an animal is, if they are not able to communicate abstract concept from one generation to the next, they have to reinvent everything from scratch each generation?