Fossils: Baby pterosaurs could fly from BIRTH and overshadowed their smaller adult rivals

The babies — or ‘flaplings’ — of giant pterosaurs likely outcompeted their smaller adult rivals in the skies of the Late Cretaceous, 100 million years ago, a study found.

This is the conclusion of researchers led from the University of Portsmouth, who studied fossil bones of flaplings found in the Aferdou N’Chaft mine in Morocco.

While pterosaurs only reach modest sizes in the Triassic and Jurassic (251.9–145 million years ago), their wingspans had reached over 20 feet by the Cretaceous.

Small-to-medium sized forms — which wingspans in the order of 3–7 feet — were still common in the first half of the period, they had become rare by the Late Cretaceous.

This has been long believed by paleontologists to be due to the fact that birds outcompete small pterosaurs and take over control of a particular ecological niche.

However, the analysis of the team shows that the tiny pterosaurs were outnumbered by their giant cousins.

This latest study builds on research that was published in July of this year and showed that pterosaurs were able to fly from the nest as soon as they hatch.

The babies — or ‘flaplings’ — of giant pterosaurs likely outcompeted their smaller adult rivals in the skies of the Late Cretaceous, 100 million years ago, a study found. Pictured: An artist’s impression showing hatchling pterosaurs

Roy Smith, palaeontologist at the University of Portsmouth, and his international team of collaborators conducted the study. 

Smith stated that over 400 specimens of pterosaurs were discovered by Smith’s team during fieldwork in Morocco’s Sahara Desert over the past 10 years.

He explained that this rock body is composed of ‘highly fossiliferous, sandstones, which are famous for their extraordinary dinosaur Spinosaurus.

‘We’d found some really big pterosaur jaws and also specimens that looked like smaller jaws — about the size of a fingernail — but these tiny pterosaur remains could have just been the tips of big jaws.

“So we had a rigorous testing to determine if the pterosaurs were from a small or juvenile species of large and giant pterosaurs.”

Mr Smith and his colleagues analysed the structure of six small pterosaur bone fragments — five from the jaw and one a neck vertebra — unearthed from the Kem Kem Group, which allowed them to determine the each of each individual at death.

‘By looking at the paper-thin section of the bones under a microscope, I could tell that they were from juveniles as the bone was fast growing and didn’t have many growth lines,’ said paper author and palaeobiologist Anusuya Chinsamy-Turan.

‘We also examined the surface of the bones and found they had a rippled texture,’ the University of Cape Town bone microstructure expert added.

“This was further evidence that they were immature bones as mature pterosaur bone have an extremely smooth surface once fully formed.

The researchers also found that the number of so-called foramina — the tiny holes in the jaw bone that allow nerves to reach the surface to aid with prey sensing — was the same in both small and big jaw fragments from the Aferdou N’Chaft site.

Mr Smith noted that “This was more evidence we were looking at juveniles’ jaws.”

“If the specimens were only the tip of a jaw there would be a fraction the amount of foramina.” Roy agreed. 

Palaeontologist Roy Smith and his colleagues analysed the structure of six small pterosaur bone fragments — five from the jaw and one a neck vertebra — unearthed from the Kem Kem Group, which allowed them to determine the each of each individual at death. Pictured: Four of the flapling jaw pieces the team analysed. Each fragment is shown here from three angles

“We also examined their surface and discovered that they had a rippled texture.” [A–D in the above]Anusuya Chunsamy-Turan, University of Cape Town paleobiologist, said that it was. This was further evidence that they were immature bones, as mature pterosaur bone have an incredibly smooth surface. [like E & F in the above]Once they are fully formed,

David Martill, University of Portsmouth, said that he was surprised by the similarities in the feeding ecology of these amazing flying animals to crocodiles.

‘With birds, there will be perhaps 10 different species of different sizes alongside a river bank — think kingfisher, little bittern, little egret, heron, goliath heron or stork for a large European river. 

“There are several species that eat slightly different prey. This is known niche partitioning. Crocodiles, on the other side, are less diverse. 

“Hatchling crocodiles live on insects along the Nile. As they grow, they eat small fish, then larger fish, then smaller mammals until they become big enough to take a zebra.

“There are many feeding niches available, but they are all occupied equally by the same species at different times in its life history.

‘It seems that pterosaurs did something rather similar, occupying different niches as they grew — a much more reptilian, rather than avian, life strategy.

Mr Smith stated that over 400 specimens of pterosaurs were discovered in the Kem Kem Group’s Sahara Desert. He said that this was the result of fieldwork done over the past 10 years. Pictured: the location of the Aferdou N’Chaft mine in Morocco where the baby pterosaurs fossils analysed in the present study were unearthed

“It is likely that the juvenile pterosaurs were eating small prey such freshwater insects, tiny fishes, and amphibians.

‘As they grew they could take larger fishes and — who knows — the biggest pterosaurs might have been capable of eating small species of dinosaurs, or the young of large dinosaur species.’

The pterosaur fossils examined by the researchers have now been entered into the collections of the Hassan II University of Casablanca in Morocco. 

The full findings of the study were published in the journal Cretaceous Research.

PTEROSAURS ARE FLYING REPTILES, WHICH LIVED IN THE JURASSIC & CRETACEOUS

Pterosaurs, which were neither birds nor bats, were reptiles that ruled the skies during the Jurassic-Cretaceous period.

Scientists have debated for years where pterosaurs belong on the evolutionary tree.

Today’s dominant theory is that pterosaurs and dinosaurs are closely related and are part of a group called archosaurs. However, this theory is still in doubt.

Although pterosaurs are not birds or bats, they were reptiles that ruled over the skies in the Jurassic to Cretaceous period (artist’s impression pictured).

Pterosaurs evolved to become dozens of different species. Some were as big as an F-16 fighter plane, while others were as small as a sparrow.

They were the first animals to be able to fly powered – not just jumping or gliding, but flapping and generating lift to travel through the air.

Pterosaurs had hollow bones and large brains with well developed optic lobes. They also had several crests on their bones that could be used to attach flight muscles.