CHICAGO (AFP) -- A locust-sized ladder and a slow-motion camera have shown that bugs can look rather than reach for footholds, researchers said Thursday. This visually-guided limb control is a complex task that researchers had thought was too sophisticated for the tiny bug brains.

“This is another example of insects performing a behavior we previously thought was restricted to relatively big-brained animals with sophisticated motor control, such as humans, monkeys or octopuses,” said study author Jeremy Niven of the University of Cambridge.
“Big-brained mammals have more neurons in their visual systems than a locust has in its entire nervous system, so our results show that small brains can perform complex tasks.”
Most insects that spend a lot of time walking -- like crickets, cockroaches and ants -- have relatively small eyes and use long antennae to “feel” their way through the environment.
Most big-eyed bugs spend a lot of time flying, so research has focused on how those insects use vision during flight.
But Niven wondered whether locusts -- which have short antenna, large eyes and spend time both on the ground and in the air -- might have to use their vision to find footholds.
His team built a miniature ladder and filmed the locusts walking across it, counting the number of times the bugs missed steps and comparing that to their missteps in other situations.
“By combining all these different experiments, we showed that locusts use vision to place their legs,” Niven said in a statement.
“We showed that when locusts can't see one front leg, they stop using that leg to reach to the next ladder rung, favoring the leg they can see.”
The discovery could help deepen understanding of movement in both people and robotics as locusts have been a model organism for studying limb control for the past 40 years, according to Niven.
The study was published in the U.S. journal Current Biology.