This fossil of an ancient winged reptile, bought from a farmer in China’s Liaoning province, tells a dramatic tale. About 160 million years ago, a female pterosaur fractured its wing and sank to the bottom of a muddy lake. Somehow, in the process of either dying or decomposing, she expelled a single egg, which has been preserved through the ages.
That’s the story that researchers told in a study published in the journal Science, anyway. And if the remarkably preserved fossil of the reptile Darwinopterus is female, they say, it sheds light on the sex differences and mating rituals of the extinct species. The preserved egg also seems to reveal new details of pterosaur reproduction.
Pterosaurs were the first vertebrates to take to the air, first appearing in the fossil record some 220 million years ago in the late Triassic period. Before their demise 65 million years ago the group evolved to include the largest flying animals ever to live – some had a wingspan of 10 metres. [New Scientist]
(more…)
The enormous wings of pterosaurs testify to the idea that these giant reptiles, which lived at the same time as dinosaurs, would have been masters of flight. But there’s one thing that nags paleontologists: pterosaur takeoff. Just how does a giraffe-sized creature get off the ground?
Not the way birds do, say Mark Witton and Mike Habib, biomechanists who for years have been modeling pterosaur flight, and have a new study forthcoming in PLoS One.
Birds rely on the strength of their legs to leap into the air or run to gain speed for take-off. Pterosaurs walked on all four limbs, and Habib has developed an anatomical model to explore how they might have launched themselves using their small hind limbs and larger “arms” which formed part of their wings. The animal could have launched itself like a pole vaulter, pushing forward with its hind limbs and using its powerful arms to thrust it high enough into the air to stretch its wings and fly away. [New Scientist]
(more…)
Paleontologists believe that majestic pterosaurs ruled the skies during the Jurassic and Cretaceous periods, soaring overhead on their leathery wings while dinosaurs stomped over the ground below. But researchers recently began wondering how exactly those “winged lizards” lifted off, as some of them weighed more than 500 pounds and were as tall as a giraffe. Last year, researchers tried to figure out how they got off the ground by looking at the largest bird now flying, the albatross. They concluded that anything much bigger couldn’t get off the ground the same way [AP], because the wing muscles wouldn’t be able to generate enough lift. But researcher Mike Habib now says pterosaurs shouldn’t be compared to birds. “The catch is that they are not built like birds,” Habib said [AP].
Habib thinks he has the answer to the pterosaurs’ launching maneuver. When the pterosaurs’ strong wings were folded they created “knuckles” that the animals rested on in four-legged stance, he says, which allowed them to take off in a motion akin to leap-frogging. The back legs kicked off first, Habib says, and then the front legs gave a mighty push to propel them into the air. This procedure would negate the need for launching aids that other paleontologists have suggested, like strong winds, a downslope, or a cliff to jump from. “Using all four legs, it takes less than a second to get off of flat ground, no wind, no cliffs,” Habib said. “This was a good thing to be able to do if you lived in the late Cretaceous period and there were hungry tyrannosaurs wandering around” [LiveScience].
(more…)
Engineers have designed a robotic spy plane that is modeled on the pterodactyls that swooped through the sky between 228 million to 65 million years ago, while dinosaurs tromped over the land below. Perhaps unsurprisingly, researchers say that their prototype is the first aircraft inspired by a pterosaur (the broader scientific name for all winged lizards).
Paleontologist Sankar Chatterjee partnered with engineer Rick Lind to design their “Pterodrone;” the two men say the work was driven in part by their admiration for the vesatility of pterosaurs. With lightweight bones and an intricate system of collagen fibers that strengthened their wings, [pterosaurs] ranged from the size of a sparrow to the size of a Cessna plane. “These animals take the best parts of bats and birds. They had the maneuverability of a bat but could glide like an albatross. Nothing alive today compares to the performance and agility of these animals” Chatterjee said [AP].
(more…)
In the primeval forests of Europe, scaly lizards leaped from the treetops and glided safely to the ground, according to a new study. Paleontologists investigated the fossilized remains of two kinds of kuehneosaurs, which were first found in the 1950s in an ancient cave system near Bristol [The Press Association]. They say that the prehistoric reptiles used extraordinary extensions of their ribs to form large gliding surfaces on the side of the body [LiveScience], which were surprisingly effective for the larger of the two species.
Researcher Koen Stein says: “We didn’t think kuehneosaurs would have been very efficient in the air, but all the work up to now had been speculation, so we decided to build models and test them in the wind tunnel in the Department of Aerospace Engineering at Bristol. Surprisingly, we found that Kuehneosuchus was aerodynamically very stable” [Telegraph]. Researchers said the Kuehneosuchus could have glided about 30 feet before touching down on the ground, while the Kuehneosaurus, with stubbier “wings,” was more of a parachutist.
(more…)
The giant azhdarchid pterosaurs have fascinated paleontologists since their fossils were first discovered in the 1970s. The largest flying animals ever to grace the planet seemed ripped from science fiction: They were taller than giraffes and had wingspans of over 30 feet.
Researchers first believed that these pterosaurs, or “winged lizards,” were scavengers that picked apart carcasses. More recently, paleontologists marveled at the idea of the lizards swooping over coastal waters to hunt like enormous seabirds. Now, after a comprehensive study of the azhdarchids’ footprints and fossils, several researchers have announced their theory that the largest pterosaurs stalked their prey on land like storks, and fed on baby dinosaurs.
(more…)
