Life reconstruction of Galahadosuchus jonesi n. gen. n. sp. The morphology of regions of the body that are not currently known for Galahadosuchus jonesi (i.e., not preserved in NHMUK PV R 10002) is inferred from comparison with Terrestrisuchus gracilis (Spiekman et al., 2023, 2024) due to the high degree of morphological similarity between these two taxa. Scale bar represents 100 mm.
Artwork by M. Dempsey.
A newly named, 215-million-year-old species of crocodile-like reptile, discovered in Gloucestershire, UK, and described in The Anatomical Record, looks rather like the sort of creature creationists imagine a transitional fossil should be: half of one modern species and half of another from an unrelated group. That, of course, is the ridiculous parody of evolution that the creationist cult teaches its followers to believe is what those crazy scientists think the Theory of Evolution describes.
In reality, this discovery is nothing of the sort. What it actually reveals is a species that raises interesting questions about the environmental pressures that shaped its evolution. It was a long-legged, fast-running crocodylomorph, resembling a greyhound with scales and a crocodile’s head and jaws. It probably lived its entire life on land, using its speed to hunt small animals. That, in turn, suggests its prey were also fast-moving, rather like the relationship between cheetahs and gazelles, which have co-evolved speed in an evolutionary arms race: one to catch fast prey, the other to escape a fast predator. It is exactly the sort of process that refutes the notion of intelligent design, yet is entirely predictable under the Theory of Evolution by natural selection.
This animal lived in what was then an area of high ground overlooking hot, arid plains during the Late Triassic. That was a period of major diversification, brought to an end by a mass extinction caused by intense volcanic activity. It was followed by the Jurassic, so comparing animals from before and after that extinction event can help us understand how life responded to those dramatic environmental changes. Among the creatures that survived were the ancestors of the dinosaurs, and later, birds and mammals.
The research team, led by PhD student Ewart H. Bodenham of University College London, with colleagues from UCL, the Natural History Museum, London, and the Staatliches Museum für Naturkunde Stuttgart, Germany, carried out a detailed analysis of this and other fossils from fissure deposits on either side of the Bristol Channel, in South Wales and South-West England. They concluded that this specimen represented a species new to science.
Crocodylomorphs and their relationship to modern crocodiles. Crocdylomorphs are the larger evolutionary group that includes modern crocodiles, alligators, caimans and gharials, together with a great many extinct relatives. In other words, the living crocodilians are not the whole lineage, but merely its last surviving branch. The group first appeared in the Late Triassic more than 200 million years ago, and the earliest members looked very unlike the semi-aquatic ambush predators we know today. They were generally small, lightly built, long-legged animals adapted for life on land. [1]
That is what makes forms such as Galahadosuchus jonesi so informative. Far from being primitive versions of modern swamp-dwelling crocodiles, they represent an earlier stage in crocodylomorph evolution, when the lineage was experimenting with active terrestrial lifestyles. The Natural History Museum describes Galahadosuchus as resembling a “reptilian greyhound”, which captures the basic idea well: this was a fast-running land predator, not a riverbank lurker. [1]
Over the following tens of millions of years, crocodylomorphs diversified into an impressive variety of body forms and habitats. Some remained terrestrial, some became semi-aquatic freshwater hunters, and some later lineages became highly specialised marine predators. Studies of crocodylomorph evolution show that the ancestral habitat for the group was terrestrial, and that movement into freshwater and marine environments happened later, and more than once, in different branches of the lineage. [2]
So, species like Galahadosuchus were not descended from aquatic crocodile-like ancestors that had come back onto land. The direction of change was the other way round. Early crocodylomorphs were land animals, and the familiar semi-aquatic lifestyle of modern crocodilians evolved later. In that sense, animals like this one are closer to the ancestral condition of the group, while modern crocodiles are specialised descendants of that originally terrestrial stock. [2]
This matters because it reminds us that evolution does not move towards a fixed goal. Modern crocodiles are not the “default” form from which all crocodylomorphs deviated. Rather, they are just one surviving branch of a once much more varied and experimentally diverse lineage, most of which has vanished. [3]
Their discovery, and the story of how they arrived at its scientific name, is the subject of a Natural History Museum news item:
New species of ancient crocodile named in honour of Welsh school teacher
- A new species of crocodylomorph from 215 million years ago named from Gloucester, UK
- The animal looks like a reptilian greyhound and was fast-moving
- It has been named Galahadosuchus jonesi for schoolteacher David Rhys Jones
A new species of crocodylomorph from the Triassic has been named from Gloucester, UK. Looking a little like a reptilian greyhound, this animal lived on land and was fast-moving, with slender, elongate limbs. It would have stalked the undergrowth for small reptiles, amphibians and early mammals when this part of the world was an upland surrounded by hot, arid plains.
The first part of the species name comes from Galahad, a knight renowned in Arthurian legend for his moral uprightness as a reflection of the crocodylomorph’s upright stance. But the second part of the name honours David Rhys Jones, a schoolteacher at Ysgol Uwchradd Aberteifi in Cardigan, Wales, who taught the lead author of the paper.
We named it after my secondary school physics teacher. Mr Jones was just such a good teacher, not only in being able to explain things well, but you could tell that he was genuinely interested in the sciences. I think that really inspired me. He also didn’t let me settle. He was very good at challenging people and helping students be the best they can be. Above all, he’s a very funny, genuine, nice guy.
Ewan H. Bodenham, lead author.
Department of Earth Sciences University College, London London, UK.
The remains of the ancient crocodile came from a series of fissure deposits found on both sides of the Bristol Channel in southern Wales and southwest England. Animals that died on the surface were washed into these caves and then covered with sediment.
Among these remains was an animal known as Terrestrisuchus. This belonged to the same larger group as modern-day crocodiles, known as Crocodylomorpha, but is one of the group's earliest ancestors. As with Galahadosuchus, but unlike today’s crocodiles and alligators, it had long, slender legs and would have lived its entire life on land.
My PhD project is looking at the evolutionary relationships of these early crocodiles. So we conducted a detailed anatomical description of this specimen, making comparisons to other early crocodiles to determine if it was another specimen of Terrestrisuchus or if it was something new.
Ewan H. Bodenham
The team found 13 key differences between the fossils, significant enough to name the specimen an entirely new species.
It adds another piece to the growing diversity of animals living in this region during the Late Triassic. This period preceded the Triassic–Jurassic mass extinction event caused by an increase in volcanic activity altering the climate.
By documenting what animals were around before this event and how they responded to it, researchers can better understand how species react in the face of massive change and upheaval.
Publication:
So, once again, creationists are left with a fossil that fits evolution perfectly but makes no sense at all as evidence for special creation. Galahadosuchus jonesi was not some absurd half-crocodile, half-something-else chimera of the sort creationist caricatures pretend evolutionary biologists expect to find. It was a real animal, adapted to a real ecological niche, shaped by the same environmental pressures and selective forces that continue to shape life today. It belongs exactly where evolutionary theory says such creatures should belong: within a branching lineage, showing one of the many experiments life has made over deep time.
And that is perhaps the most telling point. Modern crocodiles are so specialised for their semi-aquatic way of life that creationists tend to imagine the whole lineage must always have looked much the same. But fossils like this show the opposite. The crocodile line began not as lumbering swamp-dwellers, but as agile terrestrial predators, and only later did some branches evolve the familiar amphibious form. That is not the pattern we would expect from a fixed created “kind”, but it is precisely what we would expect from descent with modification over millions of years.
Far from undermining evolution, discoveries like this add yet another piece to the ever-growing picture of life's history on Earth. Every new fossil of this sort narrows another gap in our knowledge, clarifies another relationship, and reveals another chapter in the long, untidy, opportunistic process by which evolution works. And, as usual, it leaves creationism contributing nothing except a parody of science and a refusal to learn from the evidence.
Advertisement
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
Amazon
All titles available in paperback, hardcover, ebook for Kindle and audio format.
Prices correct at time of publication. for current prices.
No comments :
Post a Comment
Obscene, threatening or obnoxious messages, preaching, abuse and spam will be removed, as will anything by known Internet trolls and stalkers, by known sock-puppet accounts and anything not connected with the post,
A claim made without evidence can be dismissed without evidence. Remember: your opinion is not an established fact unless corroborated.