| Sharks hold a unique place in the sea kingdom. Among fishes they are the oldest inhabi-tants of the hydrosphere. Their tribe includes the largest fishes in the world, as well asthose most dangerous to man. Because sharks are so fascinating and dangerous, they arethe target of intense scientific study. More than two hundred scientists around the worldare working to learn their secrets and to predict their moods. Cautious by nature, the sleekand efficient creatures usually avoid clumsy human intruders, but occasionally they attackwith ferocity. Scientists want to know why, not only for their own information but also forthe safety of swimmers, divers, and sailors all over the globe. This is a book to bring you up to date on shark knowledge, fact by fact. |
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