While humans use different sized flashlights in different circumstances, porpoises use different sized beams of sound, a new study revealed. 

This new understanding of the way porpoises hunt their pray was discovered in a new study led by Danuta Wisniewska of Aarhus University. 

"If you were trying to find your car in a car park, you could use a narrow beam over a long distance and still see a lot," Wisniewska told BBC News. "But when you're trying to get your keys into the car, you would switch to a wider beam. This is similar to what we see in porpoises."

The researchers found that the size of the porpoises' sound beams can expand by as much as 50 percent during attacks, reported BBC. The size of the beam is controlled by a fatty structure in their forehead, called the melon.

Now that researchers are aware of the porpoises' strategy, which may also be used by whales and dolphins, they believe it will help them keep the mammals from accidentally chasing fish into dangerous fishing nets, reported BBC. 

"My research suggests that they really attend to their target, so we could be seeing a sort of attention blindness," Wisniewska told BBC. This suggests that when they are going after their target, the porpoise may be unaware of their surroundings. 

The study was published March 20 in the journal eLife.