New insight from ancient eggs

Largest pterosaur nest found in Xinjiang details life cycle of prehistoric flying reptile.

Rio de Janei Ro: Scientists have peered inside the largest collection of fossilised pterosaur eggs ever found, using 3D scans to reveal new insights into these flying cousins of dinosaurs, researchers said.

Pterosaurs were reptiles, and the first creatures – after insects – to evolve powered flight, meaning they flapped their wings to stay aloft instead of simply jumping and gliding.

Until now, scientists had only found some pterosaur eggs with remains inside, including three in Argentina and five in China.

But the latest report in the peer-reviewed US journal Science is based on the biggest collection to date – 215 fossilised eggs that were found in a three-meter long sandstone block in North-Western China’s Hami City, Xinjiang Uygur Autonomous Region.

Sixteen of the eggs contained fossilised remains of a pterosaur species known as Hamipterus tianshanensis, that lived more than 100 million years ago.

The fossilised pterosaur eggs were found by a team formed by Chinese and Brazil researchers during a long field survey lasting from 2006 to 2017.

“The place has been found to be rich in fossilised pterosaurs and their eggs,” said Wang Xiaolin, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology, affiliated with the Chinese Academy of Sciences in Beijing, who leads the team.

Scientists found partial wing and skull bones, along with one complete lower jaw, which fill in aspects of pterosaurs’ life cycle.

They discovered intact and well-developed thigh bones suggesting the creatures “benefited from functional hind legs shortly after hatching,” said the report.

But weak chest muscles indicate “that newborns were likely not able to fly” and “likely needed some parental care”.

Adult pterosaur bones were also scattered across the site, a sign that they returned to the same nesting spots over time, much the same as modern day sea turtles.