SOUTH -KOREAN LABS- SPECIAL : DINOSAURS & ROBOTICS

' A robot strikes terror into cowering grasshoppers ' : The origin of bird wings has long presented a puzzle to paleontologists.

Why did these structures develop in the age of dinosaurs? And what were some of the earliest wings used for, if not for flight?

In research published in the journal Scientific Reports, scientists used a robotic model of a dinosaur and terrified grasshoppers as the basis for an argument that small feathered dinosaurs might have flapped the precursors of wings to flush out insect prey.

Their proposal offers an explanation for why wings evolved before flight.

Some modern birds flash their wings as they hunt, revealing patches of white or contrasting feathers that frighten hiding prey.

The strategy - known as flush pursuit -exploits the tendency of many insects to react automatically to rapidly approaching shapes, which keeps them a jump ahead of most predators. Wing display causes insects to run too early. They reveal themselves and get eaten.

Many early winged dinosaurs were carnivores and insectivores, so Piotr Jablonski, an ornithologist at Seoul National University and an author of the paper, and his colleagues wondered if proto-wings might have evolved for a similar purpose.

The team built ''Roboteryx,'' a turkey-size black robot with the basic size and shape of Caudipteryx, a small carnivores dinosaur from 124 million years ago.

Hyungpil Moon, an engineer at Sungkyunkwan University in South Korea and an author on the study, said the robot mimicked flush-pursuits.

The team unleashed Roboteryx on grasshoppers, an insect that is susceptible to this hunting strategy with modern birds.

When Roboteryx went forth with naked arms, said Jinseok Park, a graduate student in South Korea and an author on the paper, fewer than half of the tested grasshoppers fled.

But when structures resembling PROTO-WINGS were added to the arms, 93 percent of the grasshoppers bolted. The insects scattered even more often when striped tail feathers were added to the display.

The team argues that proto-wings' effectiveness at scaring prey might have helped early winged dinosaurs in other ways. Successful flush-pursuers tend to have adaptations for fast running, maneuverability and balance.

The same wings that scared insects also allowed for rapid changes in pursuit speed and direction in small dinosaurs.

The World Students Society thanks Asher Elbein.