I found an article on Worldwide Hippies which describes a military experiment on the intuitive abilities of Native American trackers:
Then they would pair two men together who had received the same scores on all the tests. They would let one man in the pair keep his hair long, and gave the other man a military haircut. Then the two men retook the tests.
Time after time the man with long hair kept making high scores. Time after time, the man with the short hair failed the tests in which he had previously scored high scores.
Is this being made up?