Early winged reptiles were clumsy flyers, research suggests | Science

Pterosaurs, like the pterodactyl, are some of the largest animals to ever take flight, but one study suggests that early aviator reptiles were clumsy flying, only capable of traveling short distances. Research may also shed new light on the evolution of flight more generally.

Pterosaurs evolved about 245 million years ago and ruled the skies for over 150 million years, before becoming extinct at the end of the Cretaceous period along with many of their dinosaur cousins. With long membranous wings extending from the ankles to an elongated fourth toe, pterosaurs are considered the first vertebrates to have evolved powered flight. But what were these first flights like?

Professor Chris Venditti, a lecturer in evolutionary biology at the University of Reading, and his colleagues estimated the wing size and body mass of various pterosaurs from their fossil remains and combined this with information on bird metabolic rates to calculate how much energy pterosaurs would have to fly and how far they could have glided before falling to the ground.

This revealed that, although in flight, the first pterosaurs likely were clumsy aviators. “They would have flown, but relatively awkwardly. They might have climbed trees and flew from trunk to trunk, but they weren’t flying long distances and weren’t very agile in their flight, “said Venditti, whose research was published in Nature.

Later the pterosaurs were not only larger, but their wings gradually became longer than their size, increasing their efficiency: “They would have been large and graceful fliers that flew through the air, perhaps even migrating for hundreds of kilometers,” he said. called Venditti.

The research may also shed light on the evolution of flight in vertebrates more generally. Creatures like birds and bats came after the pterosaurs went extinct and relatively little is known about how they took off.

“I think people assume that flying magically bursts into the scene, but there is a big, energetic hill to overcome in order to fly,” Venditti said. “Here we see that energetic hill has been overcome, and then these animals have continued to improve. I don’t think it’s known for birds and it will be interesting to see if it’s a general phenomenon or not. “

However, not all pterosaurs mastered the art of graceful flight. Venditti found that a group of gigantic Cretaceous pterosaurs called azhdarchoids remained clumsy flyers with relatively short wings for their size, likely because flight efficiency was less important to them than to other pterosaurs.

This included the huge North American pterosaur Quetzalcoatlus, which was tall as a giraffe and wide as a light plane. “There’s no doubt they could fly, but they probably only did when they had to,” Venditti said.