London: Palaeontologists have claimed that dinosaurs may have evolved wings to woo the opposite sex, a theory which puts an end to the decades-long debate on the evolution of flight by the ancestors of modern avians.
While some researches suggested that dinosaurs learned to fly by jumping out of trees and gliding to ground, others hinted these "proto-birds" flapped their forelimbs like wings to give them more thrust to help them climb while attempting to escape from predators.
Now, a new study has revealed that a procesdins, known as sexual selection, where traits deemed as attractive by the opposite sex become more common and more pronounced through generations as they're favoured by mating animals, is actually responsible for the evolution of flight by dinosaurs.
Lead palaeontologist Dr Robert Nudds of the University of Manchester said: "The problem we see is why an animal would start holding its forelimbs out to the side in a symmetrical manner in the first place.
"Two-legged animals use their forelimbs in asymmetrical movements to help counteract the force from the legs and to stop their body from rotating as they run. If an animal started running with its limbs held out to the side, then there would be cost that would've left them competitively at a disadvantage.
"There must have been another factor involved to allow this trait to continue through the generations. One theory is that these feathered dinosaurs used their forelimbs in some sort of sexual display, so may be they ran around with their arms outstretched to show off how pretty their feathers were."
The palaeontologists used biomechanical models to simulate how Archaeopteryx and two other feathered dinosaurs, Caudipteryx and Protarchaeopteryx, would have moved in their study to reach the conclusion.
They found that the early wings of these animals would have provided little thrust to assist when running uphill and would have also increased drag.
"To me, it makes more sense that dinosaurs began to hold their forelimbs out when jumping out of trees and eventually started gliding to the ground, but the problem is the evidence in the fossil record doesn't support this.
"There may of course be gaps in the fossil record and with the ground dwelling species we have discovered so far, it seems that something other than simple natural selection drove the evolution of symmetrical forelimb posture," Dr Nudds said.