Extinct flying reptiles called pterosaurs were likely able to fly out of the nest right after hatching, a new study claims.
A team of researchers led by an expert from the University of Southampton performed computer modeling based on the fossils of several pterosaur species.
They conclude that pterosaur pups were agile and “flyworthy from the moment of hatching” – known in biology as precocity.
The boys had a wingspan of nearly 10 inches, attached to bodies that would “fit neatly in your hand.”
Amazingly, the humerus in the fry’s wings was stronger than many adult pterosaurs, indicating they were well prepared for flight.
Newborn pterosaurs were also more agile compared to adults, but less adept at traveling long distances, the team says.
Pterosaurs were not dinosaurs, but a group of flying reptiles that lived during the Triassic, Jurassic and Cretaceous Periods (228 to 66 million years ago).
Artist’s impression of a flock of adult and juvenile flamingo-like pterosaurs, Pterodaustro guinazui, taking off in the Early Cretaceous from Argentina
They were the earliest reptiles to develop powered flight and dominated the skies for 150 million years before becoming extinct some 66 million years ago.
Dinosaurs’ lesser-known cousins, the “flamingo-like” reptiles, had adept flying abilities, some the size of a jet fighter and others small as a model airplane.
The study was led by Darren Naish, a British vertebrate paleontologist at the University of Southampton.
“Juvenile pterosaurs were able to fight early in life, probably within days or hours of hatching,” they say in their paper.
‘It seems reasonable to interpret juvenile pterosaurs as nest-bound, neither helpless nor dependent on their parents.
Visual summary of how basic size-dependent fighting parameters (wing load, wingspan and aspect ratio) may have influenced pterosaur flight throughout their lives
Pterosaurs were a group of flying reptiles that lived during the Triassic, Jurassic and Cretaceous Periods (228 to 66 million years ago)
Pterosaurs were most likely bald, study finds
Pterosaurs — flying reptiles from the time of the dinosaurs — were most likely hairless and without feathers as previously suggested, a study has claimed.
In 2018, researchers from China’s Nanjing University reported finding evidence of “proturbation” branching in three fossil pterosaur specimens.
However, British paleobiologists David Unwin and Dave Martill re-evaluated this evidence and concluded that the flying reptiles had no feathers at all.
Instead, they say, the branching structures actually represent parts of the pterosaurs’ wing membranes that began to rot and unravel before being preserved.
“The idea of feathered pterosaurs dates back to the 1800s, but the fossil evidence was then, and still is, very weak,” said Dr Unwin, a pterosaur expert at the Center for Palaeobiology Research at the University of Leicester.
Study author Dr. Mark Witton of the University of Portsmouth said scientists have: only had fossils of their embryos and young to study since 2004.
“We’re still trying to understand the early life stages of these animals,” he said. “One discussion was about whether pterosaurs could fly as young or, like the vast majority of birds and bats, had to grow a little before they could fly.
“We found that these small animals – with a wingspan of 25 cm and bodies that fit neatly in your hand – were very strong, capable fliers.
“Their bones were strong enough to flap and take off, and their wings were ideally shaped for motorized – as opposed to gliding – flight.”
However, the fry would not have flown exactly like their parents, simply because they were so much smaller.
“Flight capabilities are strongly influenced by size and mass,” said Dr. Witton.
“So pterosaur pups, which are hundreds of times smaller than their parents, were probably slower, more agile fliers than the broad (but less agile) adults.”
According to the team, there are conflicting views about the behavior and lifestyle of pterosaurs during their first moments after birth.
A “flap-early” view proposes that young were capable of independent living and flapping combat — a theory this study supports.
Meanwhile, a “fly-late” model suggests juveniles were unable to fight up to 50 percent of adult size, and a “glide-early” model says young juveniles were able to fight but could only slide.
Due to the rarity of fossilized pterosaur eggs and embryos, and difficulties distinguishing between young and small adults, it is unclear whether newly hatched pterosaurs could fly.
Skeletal restorations of pterosaurs (young and adults) used in the study. (A) Sinopterus dongi hatchling; (B) S. dongi hatchling compared to adult; (C) Pterodaustro guinazui hatchling; (D) P. guinazui hatchling compared to adult
So the researchers modeled the flight ability of young using previously obtained wing measurements from four established hatchling and embryo fossils of two pterosaur species, Pterodaustro guinazui and Sinopterus dongi.
The authors also compared these wing measurements with those of adults of the same species and compared the strength of the humeral bone — which is part of the wing — of three pups with that of 22 adult pterosaurs.
Not only were the fry’s humeral bones stronger than those of many adult pterosaurs, but the hatchlings had long, narrow wings suitable for long-haul flights.
However, their wings were shorter and wider than those of adult pterosaurs, meaning they weren’t as adept at flying long distances as their parents.
Hatchlings also had a larger wing area relative to mass and body size, compared to the adult pterosaur.
These wing sizes may also have made pups less efficient than adult pterosaurs at long-range travel, but may have made them more agile fliers, allowing them to suddenly change direction and speed.
The authors speculate that the agile flying style of young pterosaurs may have allowed them to quickly escape predators and made them better suited to chase more agile prey and fly among dense vegetation than adult pterosaurs.
This could indicate that pterosaurs occupy dense habitats as young and open environments as adults, the authors said.
The study is published in Scientific Reports.
PTEROSAURUSES FLY REPTILES THAT LIVED IN THE JURASSIC AND THE CRT.
Neither birds nor bats, pterosaurs were reptiles that ruled the skies in the Jurassic and Cretaceous Periods.
Scientists have long debated where pterosaurs fit on the evolutionary tree.
The leading theory today is that pterosaurs, dinosaurs and crocodiles are closely related and belong to a group known as archosaurs, but this is still unconfirmed.
Neither birds nor bats, pterosaurs were reptiles that ruled the skies in the Jurassic and Cretaceous Periods (artist’s impression shown)
Pterosaurs evolved into dozens of species. Some were as big as an F-16 fighter jet and others as small as a sparrow.
They were the first animals after insects to develop powered flight — not just jumping or gliding, but flapping their wings to generate lift and travel through the air.
Pterosaurs had hollow bones, large brains with well-developed optic lobes, and several crests on their bones to which flight muscles were attached.