By studying various fossil records, researchers have now found that newly-hatched baby pterosaurs may have been able to fly. Pterosaurs were giant reptiles that ruled the skies about 228 to 66 million years ago.
Researchers from the UK noticed that the humerus bones (forearm bones) of the hatchlings were stronger than those of many adults, indicating that they were born strong enough to fly. The paper published yesterday in Scientific Reports adds the flying abilities of the hatchlings may have been different from the adults.
The team analysed fossils from two species, Pterodaustro guinazui and Sinopterus dongi. They compared wing measurements and bone strengths of adults and hatchlings to arrive at the conclusion.
Study co-author Mark Witton from the University of Portsmouth said in a release: Although we’ve known about pterosaurs for over two centuries, we’ve only had fossils of their embryos and hatchlings since 2004. We’re still trying to understand the early stages of life in these animals. One discussion has centred around whether pterosaurs could fly as hatchlings or, like the vast majority of birds and bats, they had to grow a little before they could take wing.
We found that these tiny animals – with 25 cm wingspans and bodies that could neatly fit in your hand – were very strong, capable fliers. Their bones were strong enough to sustain flapping and take-off, and their wings were ideally shaped for powered (as opposed to gliding) flight. However, they would not have flown exactly like their parents simply because they were so much smaller: flight capabilities are strongly influenced by size and mass, and so pterosaur hatchlings, being hundreds of times smaller than their parents, were likely slower, more agile fliers than the wide-ranging, but less manoeuvrable adults.
One of the authors Elizabeth Martin-Silverstone from the University of Bristols School of Earth Sciences said: There have been several debates about whether juvenile pterosaurs could fly, but this is the first time its been studied through a more biomechanical point of view. Its exciting to discover that even though their wings may have been small, they were built in a way that made them strong enough to fly.
The authors speculate that these flying skills may have helped the hatchlings quickly escape predators, chase agile prey and fly amongst dense vegetation.
Dr Witton added: That gives us a lot to think about with regard to flying reptile ecology. How independent were the hatchlings from their parents? Did flight style influence habitat choices, and did these change as pterosaurs grew? There’s still a lot to learn about the life histories of these animals, but we’re confident that, whatever they were doing as they grew up, they were capable of flying from the moment they hatched.