Petra Stock
When a research team struggled to find a live dinosaur to test an evolutionary theory, they built a dino-bot instead, naming their creation Robopteryx.
With an aluminium body skinned in black felt, plastic wings and black paper plumage, the robotic beast is meant to resemble a Caudipteryx – a 2-legged, peacock sized predator from the early Cretaceous – in size, shape and movement. It could just as easily be a character from Jim Henson’s The Dark Crystal.
Apart from the ostensibly fun challenge of building the dino-bot, the researchers had a serious purpose.
They wanted to test why some dinosaurs like Caudipteryx had feathers, even though they were probably unable to fly.
The researchers’ theory was that feathers were used for flapping, to scare prey out of hiding places, based on the way many modern birds hunt using a flush-and-pursue strategy.
In a series of experiments, researchers observed grasshoppers’ responses to the Robopteryx’s performance as the robot spread and flapped its wings at different distances.
They also tested grasshoppers neuro-physical responses. To do this they removed the insects’ antennae to prevent noise and view-obstruction, and exposed the ventral nerve cords, to record the animal’s responses to an animation of Robopteryx in action.
Publishing their results in Scientific Reports, the team concludes the unusual study “offers a new comprehensive perspective on the evolution of pennaceous feathers in non-avian dinosaurs”.
They say the results show positive associations between the robot flapping its wings, and the grasshoppers fleeing – with 93% of tested insects fleeing with the wings were used, compared to 47% without – suggesting support for the ‘flush-and-pursue’ theory.
Also listed in the paper are a range of other possible theories for the flightless feathers including: running while flapping, lifting and leaping, pouncing, sweeping and balancing.
