Thaindian News

Washington, Oct 14 (IANS) Researchers have identified a new type of flying reptile, providing the first clear evidence of an unusual and controversial type of evolution.
Pterosaurs, flying reptiles, also known as pterodactyls, dominated the skies in the Mesozoic Era, the age of dinosaurs, 220-65 million years ago.

Scientists have long recognised two different groups of pterosaurs: primitive long-tailed forms and their descendants, advanced short-tailed pterosaurs some of which reached gigantic size.

These groups are separated by a large evolutionary gap, identified in Darwin’s time, that looked as if it would never be filled - until now.

Details of a new pterosaur fits exactly in the middle of that gap. Christened Darwinopterus, meaning Darwin’s wing, the name of the new pterosaur honours the 200th anniversary of Charles Darwin’s birth and the 150th anniversary of the publication of On the Origin of Species.

Gaps in the fossil record are common - only a tiny proportion of all the animals and plants that ever lived were fortunate enough to become fossilised, and only a tiny proportion of these have been collected so far.

More than 20 fossil skeletons of Darwinopterus, some of them complete, were found earlier this year in north-east China in rocks dated at around 160 million years old.

This is close to the boundary between the Middle and Late Jurassic Eras and at least 10 million years older than the first bird, Archaeopteryx.

The long jaws, rows of sharp-pointed teeth and rather flexible neck of this crow-sized pterosaur suggest that it might have been hawk-like, catching and killing other contemporary flying creatures.

These included various pterosaurs, tiny gliding mammals and small, pigeon-sized, meat-eating dinosaurs that, aided by their feathered arms and legs had recently taken to the air, and would later evolve into birds.

“Darwinopterus came as quite a shock to us,” explained David Unwin, part of the research team and based at the University of Leicester’s School of Museum Studies.

“Frustratingly, these events, which are responsible for much of the variety of life that we see all around us, are only rarely recorded by fossils,” Unwin added.

“Darwin was acutely aware of this, as he noted in the Origin of species, and hoped that one day fossils would help to fill these gaps. Darwinopterus is a small but important step in that direction,” he said, according to a Leicester release.

These findings were published in the Proceedings of the Royal Society B: Biological Sciences.