Against a backdrop of looming skyscrapers, a robot dinosaur raises its feathery wings, sending its prey fleeing in terror. It is a scientific invention to show how some dinosaurs could have flapped primitive wings to scare their quarry out of hiding, similar to birds like the roadrunner.
In this case, the robo-dino's prey is a grasshopper, which responds by springing into a shrub. The interaction was shown in a video released alongside a study by researchers in Seoul, South Korea. The findings were published in the journal Nature and reported by AFP.
Dinosaurs were long thought to be the relatives of reptiles, but over the last three decades, dinosaur fossils have been discovered with feathers, leading scientists to believe they are instead the ancestors of birds.
Many of these feathered dinosaurs could not fly, so a number of theories have been put forth, including that the feathers insulated the dinosaurs against the cold, or maybe they allowed dinosaurs to move more quickly.
Some small dinosaurs may have even used their wings to knock down and trap their prey, said Piotr Jablonski, a senior author of the study.
The team of researchers proposed adding a new predatory trick to this list, which they called the "flush-pursue strategy", a method used by the passerine and the northern mockingbird that flap their wings to prompt prey to reveal its location.
To demonstrate their hypothesis, the team built a robot version of the flightless dinosaur Caudipteryx, a peacock-sized pennaraptor that lived 124 million years ago.
The metal robot -- dubbed the "Robopteryx" -- was tasked with flapping its wings to scare-up some grasshoppers, whose ancestors lived in the same period as the Caudipteryx.
"The grasshoppers more frequently escaped when the dinosaur displayed its proto-wings," said lead study author Jinseok Park.
The grasshoppers were also more likely to hop away when the robot's wings were painted with contrasting black and white patches, which was proved after testing the neural response of the grasshoppers and how the contrasting-color wings, scared them and triggered their escape reflex.