During the time of dinosaurs, the skies were ruled by pterosaurs: the first-known flying vertebrate. They are leathery winged flying reptiles that could grow so big with wings that spanned 30- feet across or more. They first appeared 220 million years ago and went extinct along with the dinosaurs around 66 million years ago during the Cretaceous-Paleogene mass extinction.

Researchers have been searching for 200 years the origins of pterosaurs but were unable to trace the evolutionary path of these reptiles and how they became airborne.

But a new study published in the journal Nature reveals that pterosaurs might have evolved from the small, dinosaur-like lagerpetids, which are their closest evolutionary relatives. This discovery will likely open new avenues for understanding pterosaurs and their flying capabilities despite their large bodies.

Origins of Pterosaurs

Pterosaurs once dominated the skies during the era of dinosaurs. They are winged creatures often referred to as the closest replica of dragons, the large serpentine mythical creature. However, their origins remained a mystery for many paleontologists for over 200 years due to a lack of convincing evidence.

An international team of scientists, led by Martin D. Ezcurra from the University of Birmingham, concluded that lagerpetids could be a sister group of pterosaurs. Lagerpetids are two-legged reptiles that existed before the pterosaurs and dinosaurs.

The Weather Channel reported that the researchers believe that the evidence they found in North America, Brazil, Argentina, and Madagascar of the newly discovered skulls and skeletons could prove their claims.

"'Where did pterosaurs come from?' is one of the most outstanding questions in reptile evolution; we think we now have an answer," said study co-author Sterling Nesbitt of Virginia Tech.

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Mystery Finally Solved

The researchers used micro-computed tomography scans and 3D reconstructions on investigating the fossils of lagerpetids that paleontologists found in the 1930s and 1940s in Texas. They found more skeletons in South America and used them in uncovering the origins of pterosaurs.

Lagerpetids are known as small, wingless reptiles that roamed around the ancient continent of Pangea around 237 to 210 million years ago. However, recent discoveries of lagerpetid skulls, forelimbs, and vertebrates in the US, Brazil, Argentina, and Madagascar revealed that lagerpetids were more similar to pterosaurs than previously thought.

Furthermore, the scientists used newer technologies like micro-computed tomographic (μCT) scanning to reconstruct the brains and sensory systems of the lagerpetids to determine the early relatives of pterosaurs.

Their analyses yielded 33 skeletal features that connect the pterosaurs to lagerpetids.

Nesbitt said that lagerpetids would have the basic body for and skull anatomy of what would be believed as the ancestors of pterosaurs. Essentially, lagerpetids are just the flightless version of pterosaurs, Smithsonian Magazine reported.

The discovery of the missing link of the evolution of pterosaurs has now helped paleontologists to conclude that the first-known flying vertebrate also evolved at the same pace as any other reptile species.

Co-author Serjoscha W. Evers of the University of Fribourg, said that flight is a fascinating behavior that evolved multiple times throughout history. And offering a new hypothesis of their relationship to now-extinct animals is a significant step forward toward understanding how pterosaurs were able to fly despite their enormous size.

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