SCIENCE LAB SPECIAL : REPTILE EVOLUTION

 

Pterosaur Family Tree : The reptile whose descendants took an evolutionary leap and stayed aloft. Pterosaurs, the flying reptiles that lived alongside dinosaurs, are an evolutionary mystery.

They appear in the fossil record fully formed, some with wingspans of 33 feet [10 meters] and there is little evidence of their ancestry. But a new fossil, described in the journal Nature, provides a glimpse of a group of reptiles related to them.

'' For the first time, we are looking into the face of a pterosaur precursor, and this animal is so bizarre,'' said Rodrigo Temp Muller, a paleontologist at the Federal University of Santa Maria in Braziland and  an author of the study.

Dr. Muller found the fossil in 2022 in Rio Grande do Sul, Brazil's southernmost state. It belonged to a lagerpetid, a group of animals whose name means ''rabbit reptile.''

Once considered early relatives of dinosaurs, they now appear to have been more closely related to pterosaurs.

Lagerpetid fossils are scarce, especially the bones from the animals head and hands. But Dr. Muller's find included the tip of a curved beak and a nearly complete lower arm, ending in curved claws shaped like scimitar blades.

Dr. Muller said that he and his colleagues had ''no idea'' what lagerpetids really looked like  until they found this new specimen, and that the sharp beaks and claws struck him as ''very strange.''

Dr. Mueller and his colleagues named creature Ventoraptor gassenae, which nods to its discovery near the Vale Veneto area, its raptorlike features and Valserina Maria Bulegon Gassen, who helped found the Federal University of Santa Maria's Paleontology center.

In life, 230 million years ago, the creature was three feet long, including its tail, and weighed from nine to 18 pounds [ four to eight kilograms ].

Venetoraptor would not have been able to fly. However, Dr. Muller hypothesizes that its large hands and curved claws could have helped it to climb trees, a behaviour that may eventually have led to jumping between branches, gliding and, eventually, true flight. [ Kate Golembiewski ].