New research has revealed that the largest known pterosaur in the world leapt into the air in order to reach the sky and fly 70 million year ago.
Experts analysed fossils of Quetzalcoatlus – the largest known animal to take to the sky – found in Big Bend National Park in west Texas, to estimate its launch sequence.
According to them, the mammoth creature jumped 8 feet in order to reach airborne. Then it lifted off using its huge wingspan of 40 feet.
The launch technique was very similar to those used by egrets or herons, however it flew more gracefully through the air than a condor or vulture.
Quetzalcoatlus was warm-blooded and is thought to have had hair instead of feathers and no tail, likely to improve its maneuverability.
Although it walked on its hind legs, the forelimb bones of its feet were too long to allow its wings to touch the ground with folded.
The Pterosaurs were not dinosaurs. They were a grouping of flying reptiles who lived in the Triassic, Jurassic, and Cretaceous Periods (228,000 to 66,000,000 years ago).
An artist’s interpretation of Quetzalcoatlus northropi – a species of Quetzalcoatlus – wading in the water. The latest research describes this species of Quetzalcotalus as having a lifestyle similar to today’s herons
This is a step-by-step reconstruction for the proposed Quetzalcoatlus launch sequence. The pterosaur jumps, then crouches before it begins to flap its wings.
Quetzalcoatlus fossils discovered in Big Bend National Park (southwest Texas) were examined by scientists
In six papers published today as a monograph by the Society of Vertebrate Paleontology, scientists and an artist provide the most complete picture yet of Quetzalcoatlus.
Professor Kevin Padian, University of California Berkeley, said that terosaurs had large breastbones. This is the area where flight muscles attach.
“This legendary flying reptile was once a myth, but most public perceptions of the animal are artistic and not scientific.
“This is our first look at the entire body of the largest flying animal, so far as we are aware.
‘The results are revolutionary for the study of pterosaurs – the first animals, after insects, ever to evolve powered flight.’
Quetzalcoatlus’ legs were much shorter than their wings so it was difficult to take off.
Instead, they likely used their strong rear legs to jump upward, and then, once the ground clearance equalled the wing length, began to flap.
Quetzalcoatlus has Quetzalcoatlus insignificantly smaller size, but herons and egrets are similar.
The landing was similar to the take-off except that it took place in reverse. Padian explained that the animal needed to lift its wings in order to slow down its descent. Then it would land with its back feet, and take a hop.
“Then, the animal puts its feet on the ground, takes a posture of four legs, straightens up, and walks away.
This is an impression of Quetzalcoatlus, cruising along a lake. Quetzalcoatlus, a warm-blooded animal, was likely to have had hair rather than feathers. This would increase its maneuverability.
Quetzalcoatlus could have been just as adept at hunting prey from the air than from the land.
Padian said that this animal was able to raise its head and neck vertically in order to swallow any small prey it grabbed with its jaws.
It could drop the great head well below the horizontal. If it was above dry ground, it may have been capable of swoop in and grab an innocent animal.
It could walk on the ground and move its neck up to 180 degrees. This would allow it full vision around all of it.
The genus Quetzalcoatlus was first identified from fossils discovered in Texas at Big Bend National Park in 1971 by Douglas A. Lawson, a geology graduate from the University of Texas at Austin.
A few years later, the first species to be discovered in the Quetzalcoatlus genus was named Quetzalcoatlus northropi in a research paper by Lawson.
Apart from Lawson’s initial descriptions of fossils, virtually no scientific research has been done based solely on the study of bones.
The lack of scientific research has meant that the mystery of how this massive animal was able to fly is largely speculation.
Some thought that it rocked along its wingtips, looking like a vampiric bat. Some claimed it gained speed running like an albatross or didn’t fly.
‘This is the first time that we have had any kind of comprehensive study,’ said Matthew Brown at the University of Texas, which currently holds all known Quetzalcoatlus fossils.
“Even though Quetzalcoatlus is known since 50 years ago, it remains poorly understood.”
Douglas Lawson, pictured with Quetzalcoatlus wings bones which he found in Big Bend National Park in 1975. He holds the humerus bone
Artist’s rendering of Quetzalcoatlus searching for food in an ancient lake. Quetzalcoatlus was approximately 12 feet tall. His 20-foot wings gave him a distinctive gait due to the fact that they touched the ground with folded.
This new research included close examination of Quetzalcoatlus bones (both confirmed and suspected), as well as other fossils from Big Bend that were used to create casts for the model.
This led to the identification of a new, smaller species of Quetzalcoatlus with a smaller wingspan – somewhere between 18 and 20 feet.
This newly-discovered species, the second in the Quetzalcoatlus genus, has been christened Quetzalcoatlus lawsoni after Douglas Lawson.
While only a few bones are known about the largest species, hundreds of fossils can be found from smaller ones.
These materials allowed scientists to create a nearly complete skull of the smaller species. They also studied how the bird flew and moved. Then they applied these insights to their larger relative.
Two Quetzalcoatlus species lived in Big Bend 70 million year ago. This was when Big Bend was an Evergreen Forest, not the desert it is today. But each had a unique lifestyle.
By examining the geological context in which the fossils were found, it was determined that the larger Quetzalcoatlus might have lived like today’s herons, hunting alone in rivers and streams.
The smaller species, in contrast, appeared to flock together in lakes – either year-round or seasonally to mate – with at least 30 individuals found at a single fossil site.
Researchers and artists over the years have depicted Quetzalcoatlus in a variety of roles, including that as a forager, skimmer and scavenger.
One of the papers, however, presents Quetzalcoatlus, who was a prober and used its long, toothless teeth to search for worms, crabs, and clams in river bottoms or lakebeds.
Sketch of Quetzalcoatlus northropi’s bones. Walking, Quetzalcoatlus northropi had an unusual gait that was different than any other animal and was distinctly distinct from the walking of the vampire bat.
Quetzalcoatlus, a carnivorous pterosaur reptile, lived in North America during the Cretaceous Period. (artist’s image)
However, there are many questions regarding Quetzalcoatlus or pterosaurs. These include the form of the wing membranes as well their attachment to the body.
But overall, the newly-published monograph provides the ‘standard go-to study of this group for years’, said Darren Naish, a British paleozoologist and pterosaur expert who was not involved with today’s publication.
‘To say that this work is long awaited is something of an understatement,’ said Naish. Naish said that the good news is it delivers and provides an incredibly accurate treatment for this legendary animal.
PTEROSAURS ARE ABLE TO EXPLAIN A LARGE RANGE FOOD SPECIES.
Pictured, a pterosaur devours a fish
In another study, experts from the Universities of Birmingham and Leicester analysed the wear on the teeth of 17 pterosaur species.
They compared these patterns with those on modern animals — such as crocodilians and monitor lizards — about whose diets we know more.
‘This is the first time this technique has been applied in this way to ancient reptiles, and it’s great to find it works so well,’ said paper author and palaeobiologist Mark Purnell of the University of Leicester.
“Often, Paleontologists are limited in their ability to determine the diets of extinct species.”
‘This approach gives us a new tool — allowing us to move from what are sometimes little more than educated guesses into the realms of solid science.’
The team found, for example, that Rhamphorhynchus — a long-tailed pterosaur from the Jurassic period — ate insects as juveniles, before moving on to fish on reaching adulthood (and around the size of a small seagull.)
This suggests that the young were left by their parents to fend for themselves — a trait which is common among reptiles, but not among birds.
Also, the team discovered broad shifts throughout the evolutionary history the pterosaurs.
Jordan Bestwick (University of Birmingham), paper author, and paleobiologist, said, “We discovered that the earliest forms of Pterosaurs ate mostly crunchy invertebrates.”
“The evolution of birds coincides with our shift to eating meat or fish.”
‘We think it’s possible, therefore, that competition with birds could explain the decline of smaller-bodied pterosaurs and a rise in larger, carnivorous species.’
Nature Communications published the full results of this study.