The longer you stay and watch them, the more their personalities emerge as they swing from tree to tree, playing, teasing each other, cleaning themselves and feeding.

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To all intents he had the match in the bag when match referees gave him the 450-yard 10th after Woods moved a tree branch unintentionally during his swing.

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Dr. Samuel Putnam , an assistant professor of psychology at Bowdoin College in Maine, says thrill seeking behavior is mostly genetic, and that signs of it--from climbing the highest tree to swinging as high as possible on a swing set--can be recognized from very early ages.

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