Because a small insect's center of gravity is so easily disrupted, many tiny leapers spin uncontrollably. But mantises seem to have great accuracy when they jump, so the researchers figured they must be doing something special. Here's what a successful jump looks like:
As it turns out, mantises actually harness the spin of their bodies -- the way they're pulled to and fro by the momentum of a jump -- to make sure they hit their target and stick to it.
"We had assumed spin was bad, but we were wrong -- juvenile mantises deliberately create spin and harness it in mid-air to rotate their bodies to land on a target," study author Malcolm Burrows, a professor at Cambridge University's Department of Zoology, said in a statement.
Instead of compensating for an uncontrollable spin, the insects were controlling their leaps every step of the way.
During a jump lasting less than a tenth of a second, mantises were rotating their legs (front and hind) and abdomens in precise movements (and not always in the same directions) to control the spin of their bodies. The momentum is shifted from one body part to the other so they're poised to grab the target at just the right moment.
"This is akin to asking an ice skater who is rotating at the same speed as these mantises to stop suddenly and accurately to face a specific direction," Burrows said.
Because the abdominal movement seemed so vital -- the mantises even seemed to do jumping prep by curling their abs up before taking off -- Burrows and his co-author Gregory Sutton of the University of Britol glued the segments of the abdomen together to keep them from following this intricate spin.
As you can see in the video at the top of the post, the mantises didn't hit their target less accurately. But instead of grabbing hold, they bounced right off the target; showing just how vital this controlled spin is to the success of their leaps. Without the abdomen moving in precise tandem with the insect's four legs, it wouldn't be able to position its body for a perfect landing.
Burrows and Sutton hope that further research can reveal the brain mechanisms behind the choreography (do the mantises plan it out beforehand, or are they planning their movements in lightning-quick real time?) and think that roboticists could learn something from the tiny jumpers.