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Massey/GettyCan sharks do math? A new study suggests the sea creatures, among other animal species, track prey using mathematical patterns.
How does a hungry shark decide where to look for a tasty meal when there’s no tempting morsel in plain sight? Sharks and other predatory sea animals may actually use math when they hunt, according to new research.
The study, which appeared online in the journal Nature, found that some animals move in a specific pattern called a Levy walk.
On a graph, the Levy walk, which consists of rare, long forays in one direction, has a squiggly pattern, and its shape stays the same no matter what the viewing scale is.
“Living organisms, when allowed to make freely willed decisions, seem to end up obeying some kind of mathematical law,” said Gandhimohan Viswanathan, a theoretical physicist not involved in the new research, who works at the Federal University of Alagoas in Maceio, Brazil, according to Science News.
While it was once thought that animals foraged by moving in random directions, biologists have begun reporting Levy behavior in species as varied as deer and bumblebees, according to Science News. A team of researchers led by Viswanathan reported in 1996 that wandering albatrosses, monitored while wearing radio-tracking devices, took long trips following the Levy pattern.
According to David Sims, a researcher at the Marine Biological Association of the United Kingdom in Plymouth, there is now firm evidence that 14 species of open-ocean marine predators engage in Levy behavior. Sims and colleagues collected more than 12 million data points showing how the animals moved through the ocean over some 5,700 days.
Many animals exhibited the Levy behavior just part of the time, and it showed up most frequently in waters where food was scarce, reports Sims. When the water had lots of food for the predators, they tended to move more randomly. It may be that they use the Levy flight motion to increase their chances of finding food, according to Viswanathan.
The research is “the strongest evidence yet that these Levy patterns are exhibited by wild animals,” Sims says.
Some experts don’t think the new study holds water. While he has not analyzed the new data, Simon Benhamou, ecologist at the National Center for Scientific Research in Montpellier, France, says that statistical errors can make it seem as if Levy behavior is real when in fact it’s not. And, he says, the Levy pattern studies assume that sharks and other animals are “fully stupid, unable to process information and act accordingly” when their environment changes.
While Sims and his team found that the Levy behavior is practiced by marlin, swordfish and tuna, as well as sharks, there is one species that apparently doesn’t turn to math when hunting: the great white shark.