October 7, 2022 | David F. Coppedge

Has a Pterosaur Ancestor Been Found?

Looking more closely at a fossil found 115 years ago,
evolutionists visualize it running, sprouting wings and flying into the sky

 

Scottish fossil reveals clues about the earliest pterosaurs (British Natural History Museum, 5 Oct 2022). Look at the artist conception at the top of the press release. Does it look like a pterosaur?

Scleromochlus taylori, artist conception c. Gabriel Urgueto for Natural History Museum

Even allowing for generous artistic license in the coloration of this animal, it seems a stretch to consider this creature, dubbed Scleromochlus, as an ancestor to pterosaurs. It walks on all fours. It has no wings. It is described as “cursorial” – i.e., moving on the ground. It looks like a lizard but with legs underneath rather than splayed out to the side, as with modern lizards. Nothing about the forelimb and digits shows any beginning of extension toward growing a wing.

Pterosauromorpha, by contrast, is a very large clade of flying reptiles. Found worldwide, they came in a tremendous range of sizes, from some that could fit in your hand to others as tall as giraffes. Each had radically extended forefingers that supported a membranous wing attached to the body. They were capable of powered flight. Some scientists think that Quetzalcoatlus, the giraffe-sized beast with its enormous pointed head, was able to leap from a standing position and become airborne. That would have required extreme muscle strength and coordination. On land, pterosaurs folded their wings up neatly, and are thought to have walked on all fours using their elbows as legs. In the fossil record, they appeared abruptly, and then disappeared with the dinosaurs.

Pterosaurs vary in size from those that can fit in the palm of a hand to ones as large as giraffes. The muscle attachment would have had to be precise for each species under a wide range of sizes and habitats. From Witton, 2013, p. 250.

Where Does This Fossil Fit?

The fossil of Scleromochlus, found in 1907, “has been the subject of debate since its discovery,” the article says. So why is it being touted as a pterosaur ancestor now? The picture of the fossil looks nondescript and difficult to interpret. This time, Professor Paul Barrett and a team were able to discover hidden bones inside the rock with micro-CT scanning. The technique allowed them to piece together more of the skeleton than had been seen before. Behold, it’s not a pterosaur ancestor after all! But with some imagination, Dr Barrett says, one can visualize the unknown ancestor.

‘Scleromochlus was probably an agile, ground-dwelling animal which, while not a direct pterosaur ancestor, gives us some indication of what that ancestor might have looked like.’

And now, a word from our sponsor, Emperor Charley the Magnificent:

How did Pterosaurs Evolve?

Pterosaurs emerged over 220 million years ago in the Late Triassic.

The little boy watching the parade asks his daddy, “But how do they know it evolved?”

Reading from the printed program handed out by Professor Paul to the townspeople, Daddy explains how science figured this out:

Unlike other ancient reptile groups, whose gradual evolution can be tracked through a number of intermediate stages, the earliest-known pterosaurs were already highly specialised by the time they first show up in the fossil record.

‘The earliest pterosaur fossils that we know are already distinctly pterosaur-like and show the suite of specialised features that make this group distinctive,’ Paul explains.

We don’t have any reptile fossils that show an intermediate stage of development, so we have very little to guide us on what the initial stages of transformation from a crocodile or lizard-like ancestor into a pterosaur were like.’

The boy still doesn’t get it. ‘But if there are no intermediate fossils, how do they know it evolved?’ Daddy explains that they don’t know yet, but if they can just keep looking, the evidence may turn up some day. Scientists tell us that everything evolved, so the missing link must be out there somewhere.

The boy stares at the artwork. ‘How do they know this lizard-like thing became a pterosaur?’, he asks. ‘Did it climb up trees and leap into the air or something?’ Daddy reads from the program notes.

Other aspects of its biology remain uncertain. While Scleromochlus was not adapted for climbing, the researchers could not discount it as a possibility. It is also uncertain how it may have looked.

‘We don’t see any armour in these animals, which removes a feature which could have suggested Scleromochlus was a more crocodile-like animal,’ Paul says. ‘There are also impressions that might represent integument, but they’re not well enough preserved to demonstrate whether the skin was scaly or downy, if it represents skin at all.

‘You just need to believe the experts, son’, Daddy assures the boy. They published all the details in a peer-reviewed journal, so they must know. Well-known evolutionary paleontologists like Stephen Brusatte are listed as co-authors.

Source: Foffa et al., “Scleromochlus and the early evolution of Pterosauromorpha,” Nature, 5 Oct 2022.

Media Joins the Parade

Triassic specimen found to be early relative of pterosaurs a century after its discovery (University of Birmingham via Phys.org, 5 Oct 2022). “The results support the hypothesis that the first flying reptiles evolved from small, likely bipedal ancestors,” this article reads with confidence. “The finding settles a century-long debate,” the reporter continues. “There had previously been disagreement as to whether the reptile, Scleromochlus, represented an evolutionary step in the direction of pterosaurs, dinosaurs or else some other reptilian offshoot.

And now, another word from the parade sponsor, Emperor Charley the Magnificent, brought to you by Virginia Tech.

Professor Sterling Nesbitt at Virgina Tech said: “Pterosaurs were the first vertebrates to evolve powered flight and for nearly two centuries, we did not know their closest relatives. Now we can start filling in their evolutionary history with the discovery of tiny close relatives that enhance our knowledge about how they lived and where they came from.

A search for Scleromochlus turns up dozens of sources echoing the story throughout the internet.

Daddy points the boy to a lizard running along the sidewalk. ‘Because of what science has learned, that lizard* may some day turn into a flying giraffe! Imagine that. Isn’t Darwinism special?’

But how do they know?, the boy whispers to himself quietly, fearing another blast of hot air.

Update 10/28/2022: Paleontologist Günter Bechly affirms that “Pterosaurs appear abruptly and fully formed in the fossil record.” He discusses Scleromochlus and other proposed transitional forms, saying that “those reptiles fail to show even the slightest adaptations for gliding or flying, or any trace of incipient pterosaur wings,” adding that “Even the relationship of these fossils is highly disputed.” He concludes, “Outside of Darwinian fantasy land, we indeed lack any transitional fossils that would document an assumed gradual evolutionary development of characteristic pterosaur wings.” Evolution News, 10/28/2022.

*We know that lizards are not supposed to be related to the dinosaurs and pterosaurs. But if scientists can say they are lizards in Latin (dinosaur = “mighty lizard” and pterosaur = “winged lizard”), then we can say it in English.

 

 

 

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