I just finished reading Godforsaken Sea -- Racing the World's Most Dangerous Waters, by Derek Lundy, about sailboat racing in the southern hemisphere. It was very good in describing all the things that can go wrong due to storms and icebergs.

"Some recent studies suggest that there may be a genetic predisposition for some people to seek out new and challenging sensations, based on how their bodies respond to dopamine. One form of the gene that is responsible for dopamine receptors is larger than others. That gene form produces a receptor that doesn't respond as well to dopamine as the smaller form. People with that larger version of the gene won't experience the effects of dopamine secretion as readily as people with the smaller one. They may, therefore, be driven to activities that stimulate the production of larger amounts of dopamine. Depending on many other factors, both genetic and environmental, those activities may take the form of extreme sports or other dangerous activities." (pp.183-4) "... some people need to look for danger, to seek more sensation than our society can legally provide. Extreme sports are one result.." (p.194)

Extreme sports are a good indicator of extreme stupidity.