Praying mantises are incredibly agile jumpers, say researchers who used high-speed video to capture the extraordinary precision of their leaps that happen in the blink of an eye.
Losing control while performing a jump through uncontrolled spinning is an ever-present risk, and the risk is greater the smaller the creature doing the jumping because their center of gravity is easily disrupted, the scientists say.
This has led researchers to believe small insects can't control the spinning and therefore, it can lead to lots of crash landings.
However, the video of wingless, young praying mantises making jumps showed how they were actually making use of the spinning effect, repositioning their bodies in mid-leap to arrive accurately at an intended target, the researchers found.
By rotating their abdomen and legs simultaneously but in different directions, shifting their body parts clockwise and counter-clockwise in an aerial "ballet," the mantises are able to line their bodies up precisely with the objective of their leap, the scientists report in the journal Current Biology.
"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," says study author Malcolm Burrows in the zoology department at Britain's Cambridge University.
The spin shifts the mantis' momentum between various body parts to position them to grab onto the jump target at the exact moment of landing, he says.
"As far as we can tell, these insects are controlling every step of the jump," he explains. "There is no uncontrolled step followed by compensation, which is what we initially thought."
In experiments, when the scientists brought the targets ever closer to the mantises, the insects would spin themselves even faster to make sure their bodies were aligned with the jump target -- a stick -- after landing, which allowed them to immediately grasp it.
Something the researchers claim they still don't understand is how the mantises accomplish their aerial ballet so quickly, in jumps that can take less than a tenth of a second.
"We can see the mantis performs a scanning movement with its head before a jump," Burrows says. "Is it predicting everything in advance or does it make corrections at lightning speed as it goes through the jump?
"We don't know the answer between these extreme possibilities," he says.
Researchers developing mobile robots could learn something from the mantises, he adds, as jumping can be an efficient form of locomotion.
"Jumping makes sense -- but controlling the spin in jumping robots is an almost intractable problem," he notes.
The baby mantises could serve as natural case of a possible mechanical setup to solve the problem, he says.
