For 400 million years, the shark has cruised the world's seas. The frightening white pointer or great white in particular is a superbly designed hunting instrument. Attacks increased in 2000 according to the International Shark Attack File, a database of all known attacks since 1580 based at the University of Florida at Gainesville.
Director George Burgess said the increase was almost certainly a combination of more people spending time in the water, often in remote parts of the world and more reporting of incidents via the internet.
"Attacks are an odds game on how many hours you are in the water. Some attacks are beginning to pop up in far-flung corners of the earth as tourists can afford to vacation in areas they wouldn't normally have gone to in the past," Dr Burgess said. "Lots of these tourists gleefully enter waters that native people - who learn over the years where to swim and not swim - might not go."
Last summer, five people were killed by white sharks in Australian waters. Marine biologist Barry Bruce of the Commonwealth Scientific, Industrial and Research Organisation said shark attacks were so rare the event always attracted publicity. But there was no evidence attacks were becoming more frequent or that shark behaviour was changing.
"The problem for scientists is getting enough information to understand the patterns, to understand why sharks are in certain areas at certain times," he said. "It's easy for people to come up with an idea about attacks. But that doesn't make it true. White sharks scare the willies out me. They're magnificent creatures and fortunately I've only seen them when I want to and when I'm protected - I have a healthy respect for them."
Last year marine scientists at the organisation attached satellite transmitters to two sharks. One tagged in March was tracked for more than 113 days, the shark travelled 3,000km at a speed of 1.2-3.3km an hour.
Research carried out by Ross Miller, head of a materials engineering group at the University of Adelaide, found the force exerted by a 3m shark bite was 1.5 tonnes. "That shark would be capable of lifting a standard sedan car with its jaw muscles," Professor Miller said.