The next two most-attacking sharks, the tiger and bull, have a combined attacks with 59 deaths. Deadly animals: Here are the deadliest wild animals in North America — and states with the most fatal attacks. Shark attacks: was an 'unusually deadly year' for shark attacks, with the most deaths since Nathan Hart, director of the university's neurobiology department and co-author of the study, said baby white sharks are also learning how to hunt for bigger food like seals, which is a "learning process that could be prone to mistakes.
The researchers are trying to find new ways to help keep humans safe from attacks, such as the use of LED lights to change silhouette shapes. But this presumed similarity has only previously been assessed based on human vision, using underwater photographs to compare their silhouettes. In our study, published last month , we and our colleagues in Australia, South Africa and the United Kingdom compared video footage of seals and of humans swimming and paddling surfboards, to predict what a young white shark sees when looking up from below.
We specifically studied juvenile white sharks — between of 2m and 2. This might be because juvenile sharks are more likely to make mistakes as they switch to hunting larger prey such as seals. Our results showed it was impossible for the virtual visual system to distinguish swimming or paddling humans from seals.
This suggests both activities pose a risk, and that the greater occurrence of bites on surfers might be linked to the times and locations of when and where people surf.
But sharks can also detect prey using other sensory systems, such as smell, sound, touch and detection of electrical fields. At least that's the premise behind the "mistaken identity" theory that tries to explain why sharks sometimes attack people.
Credit: Taronga Zoo. At Taronga Zoo, researchers have this month run a series of experiments to understand what drives a shark to attack by mimicking what they see and hear underwater. Mistaken identity? Researchers are testing the idea that sharks mistake surfers and swimmers for seals. With this information, they hope to develop specific shark repellents, such as making surfboards less attractive with lights; a feature they'll test on South Africa's white pointer population later this year.
The researchers found that the shape and motion of humans look the same as seals from a shark's perspective. The study, published Tuesday Oct. Related: Aahhhhh! These sharks start hunting seals when they are about 8.
They develop a search image for their prey and combine that with other sensory information, such as smell, to know what to eat. Great white sharks lack color vision and cannot see fine details like the human eye can.
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