Meet the Predator that Becomes Blind When It Runs After Prey
by Ed Wong
There are 2,600 species of these long-legged predatory insects, and the fastest can sprint at up to 5 miles per hour, covering 120 of its body lengths in a single second. For comparison, Usain Bolt covers just 5 body lengths per second. To match the beetle, he’d have to run at 480 miles per hour.
Tiger beetles use this incredible speed to run down both prey and mates. But as they sprint, their environment becomes a blur because their eyes simply can’t gather enough light to form an image. They have extremely sharp vision for insects, but when they’re running, the world smears into a featureless smudge. To compensate, the beetle has to stop to spot its prey again, before resuming the chase.
It seems like a bad evolutionary joke: a hunter that loses sight of its prey whenever it runs.
But tiger beetles don’t mind because… well… they are really, really fast. They can afford to stop in the middle of a chase because they are so ridiculously quick when they’re in motion. It’s like the aforementioned Bolt pausing at the 50-metre mark for a drink, and still winning…
(read more: Not Exactly Rocket Science - Nat Geo)
photos: Daniel Zurek