Several groups of carnivorous dinosaurs – Tyrannosaurus, Spinosaurus, and their members Velociraptor The family crept into the Bexhill-on-Sea region of present-day East Sussex, England, about 135 million years ago (early Cretaceous period), according to new research.
Early Cretaceous floodplain in southeastern England, 135 million years ago. A spinosaur (center) takes over the carcass of an ornithopod, tormenting smaller tyrannosaurs (left) and dromaeosaurs (bottom right). Image credit: Anthony Hutchings.
Dr Chris Barker, a palaeontologist at the University of Southampton, said: “Carnivorous dinosaurs are rare in the Cretaceous deposits of southern England.”
“Normally it is the Isle of Wight dinosaurs that attract our attention. Little is known about the older Cretaceous specimens recovered from mainland sites.”
In this study, Barker and his colleagues examined assemblages of theropod teeth taken from animals. Wadhurst Clay Formationmainly collected from the Ashdown Brickworks area near Bexhill, East Sussex.
Theropod teeth are complex and vary in size, shape, and serrated edge anatomy.
The authors used several techniques to analyze the fossils, including phylogenetic methods, discriminant methods, and machine learning methods.
“Dinosaur teeth are durable fossils and are typically preserved more frequently than bones, so they are often important when you want to rebuild ecosystem diversity,” Dr. Barker said. .
“There are rigorous methods that help identify teeth with high accuracy.”
“Our findings suggest the presence of spinosaurs, medium-sized tyrannosaurs, and small dromaeosaurs. Velociraptor-There are some theropods in these deposits. ”
A theropod tooth excavated from the Wadhurst Clay Formation. Scale bar – 10 mm. Image credit: Barker others., doi: 10.1002/spp2.1604.
The discovery of Tyrannosaurus is particularly noteworthy. This is because this group has not been previously identified in sediments of this age and region.
These tyrannosaurs would have been about one-third the size of their more famous cousins. tyrannosaurus rexand likely hunted small dinosaurs and other reptiles in floodplain habitats.
“Assigning isolated teeth to a group of theropods can be difficult, especially since many traits evolve independently between different lineages,” says Dr. Lucy Handford. Student at York University.
“Therefore, we employed a variety of methods to refine our findings, leading to a more reliable classification.”
“It is very likely that further discoveries will be made by re-evaluating the theropod teeth elsewhere in the museum.”
Dr Darren Naish, a palaeontologist at the University of Southampton, said: 'Southern England has an extremely good record of Cretaceous dinosaurs, and the various sedimentary layers here are among the world's best in terms of geological age and the fossil content they contain. It's also unique.”
“These East Sussex dinosaurs are older, more mysterious, and less well known than the better-known Cretaceous deposits of the Isle of Wight.”
“We've been hoping to find out for decades which groups of theropods lived here, so the new study's conclusions are really interesting.”
of findings appear in the diary paleontology papers.
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Chris T. Barker others. 2024. Theropod dinosaur diversity of Lower Wealden, England: analysis of the tooth-based fauna of the Wadhurst Clay Formation (Lower Cretaceous: Valanginian) through phylogenetic, discriminant, and machine learning methods. paleontology papers 10 (6): e1604;doi: 10.1002/spp2.1604
Source: www.sci.news
