They could not fly. Pterosaurs became Earth's first flying vertebrates, with birds and then bats appearing much later. Lagerpetids also appear to be closely related to dinosaurs, the researchers said. The oldest-known dinosaur dates to about million years ago. Pterosaurs disappeared 66 million years ago in the asteroid collision that also doomed the dinosaurs.
Nifty 18, Zomato Ltd. Market Watch. ET NOW. Brand Solutions. Video series featuring innovators. ET Financial Inclusion Summit. Malaria Mukt Bharat. Wealth Wise Series How they can help in wealth creation. Honouring Exemplary Boards. Researchers in Australia have announced a new species of flying reptile from a fossil discovered in western Queensland, saying: "It's the closest thing we have to a real life dragon.
The fossil is believed to come from the largest flying reptile ever uncovered in the country, a pterosaur that would have soared over the vast inland sea that once covered much of the outback. Tim Richard, a PhD student at the University of Queensland's Dinosaur Lab, said: "The new pterosaur, which we named 'Thapunngaka shawi', would have been a fearsome beast, with a spear-like mouth and a wingspan around seven metres.
Mr Richard led the research team analysing a fossil of the creature's jaw which was discovered in western Queensland, the northeastern Australian state, and published the research in the Journal of Vertebrate Paleontology. He said: "It's the closest thing we have to a real life dragon.
It was essentially just a skull with a long neck, bolted on a pair of long wings. This thing would have been quite savage. Pterosaurs are the winged cousins to dinosaurs. Over species of the reptiles have been discovered, varying between the size of a fighter jet to as small as a sparrow. Above the whole tableau soars the most impressive Araripe species, a giant called Tupuxuara, with a foot 6-meter wingspan.
This toothless pterosaur had a rounded four-foot-long 1. Paleontologists can paint this vivid portrait of Araripe pterosaurs because their bones were exquisitely fossilized, intact and uncrushed, within the quiet sediments at the bottom of the lagoon.
By comparison, the flattened pterosaurs from most other sites around the world look like prehistoric roadkill. The Araripe fossils have enabled researchers to get a better fix on what pterosaurs actually looked like and how their bones fit together. They can see, for example, how the upper arm bone, or humerus, produced the flapping motion that kept pterosaurs in the air.
The bone looks something like a hatchet: a stout shaft topped by a flared-out blade where it joined the shoulder. The wide head must have provided a broad anchoring point for the powerful chest muscles pterosaurs needed to flap their wings. The weight of these large muscles was offset by lightweight, eggshell-thin bones filled with air.
Larger species had slender struts inside hollow wing bones, adding strength without many additional pounds. So even with wings almost as wide as a house Tupuxuara may have weighed no more than a child. Hollow bones gave pterosaurs an advantage during life but were a hindrance to their immortality. Pterosaur skeletons were so delicate that they survived as fossils only when their corpses came to rest in a protected environment.
For that reason most pterosaur remains come from species that lived near the ocean—the soft seafloor ooze entombed their bodies for eternity. Even with the new discoveries, the rarity of fossils leaves major gaps in knowledge about pterosaurs. No one knows how they evolved flight, why they vanished, or exactly what they looked like.
Debate swirls around these reptiles like the air currents they once rode. Controversy has surrounded pterosaurs since the first discovery of one at the end of the 18th century. At the Bavarian State Collection of Paleontology and Historical Geology in Munich, paleontologist Peter Wellnhofer pulled out a large drawer filled with fossils and pointed out a fragile skeleton, which was no bigger than my hand.
Embedded in a slab of limestone million years old, the creature lay with its mouth agape in a pose of prehistoric horror. It has a long toothy snout, a giraffe-like neck, and lanky legs, but its most unusual feature is its forelimbs. Next to three small fingers is a fourth that extends ten times the length of the other digits. Cosimo Alessandro Collini, the first natural historian to study the fossil, was stumped when he described it in Seventeen years later the great French anatomist Georges Cuvier deduced that the animal was a flying reptile, whose fourth finger supported a wing.
Although the wing surface had not fossilized, Cuvier surmised that a membrane of skin had attached to the forelimb in life. He later named the fossil Pterodactylus, combining the Greek words for wing and finger. A few decades later the term pterosaur, or winged reptile, was coined to describe the growing list of similar fossils.
In a remarkable pterosaur specimen came to light that confirmed Cuvier's deduction. Unlike earlier fossils, this new find near the Bavarian town of Solnhofen contained delicate wing impressions, clear proof that extinct reptiles could fly. Even with more than a thousand pterosaur specimens known today, such wing impressions remain rare. Normally only bones survive the fossilization process.
Material as ephemeral as skin or hair disintegrates long before an animal turns to stone. But time was kind to the pterosaurs that died near Solnhofen because many were preserved in the sediments of a Jurassic lagoon. Wellnhofer slid open another drawer and gingerly removed a gull-size pterosaur named Rhamphorhynchus, with a wing so beautifully preserved that I could see impressions left by delicate folds of its skin. Under the microscope the surface of the wing looked corrugated, almost like corduroy.
This texture comes from fine fibers only two-thousandths of an inch thick that were inside the membrane. They could also have kept the wing bent, cambering its surface.
Some million years after Rhamphorhynchus flew, aeronautical engineers would use the same cambered-wing principle when building planes. Rhamphorhynchus would have displayed its piloting skills while fishing for food over the Jurassic lagoons, Wellnhofer said, pointing out the spearklike snout on one specimen. It is very long and pointed. They skimmed above the water, with just the tip of the lower jaw plowing through the water.
And if they met a fish, they could catch it with their long slender teeth like so," he said, clamping his hands together. Pterosaurs could carry out these precise actions because they had a highly specialized brain. Their enlarged cerebellum, a characteristic more like the brain of birds than reptiles, provided the enhanced muscular coordination required for maneuvering on the wing. Such adaptations of brain and body must have taken untold millennia to transform a four-legged reptile into a full-fledged flier.
But the evolutionary path to the air remains in dispute. Most researchers conclude that pterosaurs descended from a small arboreal reptile that spent its life jumping between branches. Like the modern flying squirrel, this creature would have spread its limbs, using flaps of skin attached to its limbs and body to brake its fall.
Over many generations the fourth finger on each forelimb grew longer, enlarging the skin surface and enabling the animal to glide farther.
The competing theory holds that pterosaurs evolved from bipedal reptiles that ran along the ground, perhaps spreading their arms for balance. Through gradual growth, the forelimbs would have evolved into wings. All paleontologists admit, however, that the question of origins remains open, awaiting new fossil discoveries of early forms of pterosaurs.
The earliest known pterosaurs come from the mountains of northern Italy, where Dalla Vecchia has spent years prospecting for flying reptiles. These species have shorter wings than later forms, but there is evidence that they were over open water. I found proof of this prowess while examining the fossil of a Eudimorphodon, a million-year-old pterosaur unearthed near Bergamo, Italy, in Under a microscope in the Civic Museum of Natural Science in Bergamo, several fish scales glistened in the abdominal region of the specimen—the remnants of this pterosaur's last meal.
Rupert Wild, a German paleontologist who discovered the scales, suggests that the pterosaur caught its prey much like brown pelicans do, dive-bombing under the water to grab its victims. Until the discovery of Eudimorphodon, paleontologists thought that pterosaurs originated million years ago, near the beginning of the Jurassic period.
The find pushed the record back 15 million years, to the Triassic period. When Eudimorphodon first took to the skies, it gazed down on a landscape completely alien to modern eyes. The continents were gathered together into one landmass called Pangaea that stretched nearly from Pole to Pole.
Crocodile-like reptiles reigned as top carnivores, while dinosaurs were increasing in number. The balance of power shifted as the Triassic closed. Extinctions dethroned the prevailing reptiles, and fleet, meat-eating dinosaurs took over.
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