Steve Irwin, well known for stunts with crocs, snakes, whatever died after an encounter with a stingray on the Great Barrier Reef. Long time divers will know that stingrays can defensively strike and embed a sharp boney process virtually anywhere close to their body, top and bottom. Apparently, a ray pierced Steve's heart with this spine.
It pays to stay well above rays when swimming over the bottom for this reason. Stingrays are known for defensive abilities, i.e. you won't see one chase you tail first. Just keep a reasonable distance away.
http://edition.cnn.com/2006/WORLD/as...in.remembered/
http://www.hindu.com/thehindu/holnus...0609051710.htm
Some video about Steve and the accident appears at:
http://www.sun-sentinel.com/