May 1, 2024

Mega-Predator: Fossils Discovered of Giant Sea Monster That Ruled the Oceans 66 Million Years Ago

Mosasaurs appeared like a Komodo dragon, except with flippers instead of legs, and a shark-like tail fin. Mosasaurs ended up being bigger and more concentrated on the last 25 million years of the Cretaceous period, taking niches as soon as filled by other marine reptiles like plesiosaurs and ichthyosaurs. Some developed to consume little prey like fish and squid. Others crushed clams and ammonites. The new mosasaur, called Thalassotitan atrox, evolved to take advantage of all the other marine reptiles.
Here, near the end of the Cretaceous, the Atlantic flooded northern Africa. Those fed little fish, feeding bigger fish, which fed mosasaurs and plesiosaurs– and so on, with these marine reptiles becoming food for the enormous, meat-eating Thalassotitan.
Nick Longrich with the mosasaur fossil. Credit: Nick Longrich
Thalassotitan, had an enormous skull measuring 1.4 meters (5 feet) long, and grew to nearly 9 meters (30 feet) long, the size of a killer whale. A lot of mosasaurs had long jaws and slender teeth for catching fish, but Thalassotitan had a short, broad muzzle and massive, conical teeth like those of a whale. These let it take and rip apart big victim These anatomical adaptations recommend Thalassotitan was a pinnacle predator, sitting at the top of the food cycle. Essentially, the huge mosasaur occupied the same environmental niche as todays killer whales and great white sharks.
Thalassotitans teeth are damaged and frequently worn. Eating fish wouldnt have produced this sort of tooth wear. Instead, this recommends that the huge mosasaur attacked other marine reptiles, breaking, grinding, and breaking its teeth as it bit into their bones and tore them apart. Some teeth are so heavily harmed they have been almost ground down to the root.
Fossilized remains of victim.
Remarkably, possible remains of Thalassotitans victims have actually also been found. They would have been absorbed in Thalassotitans stomach prior to it spat out their bones.
” Its circumstantial proof,” said Dr. Nick Longrich, lead author on the study, released today (August 24, 2022) in Cretaceous Research. Longrich is Senior Lecturer from the Milner Center for Evolution at the University of Bath.
Size comparison of Thalassotitan atrox. Credit: Nick Longrich
” We cant say for certain which types of animal ate all these other mosasaurs. However we have the bones of marine reptiles eliminated and eaten by a large predator.
” And in the exact same place, we find Thalassotitan, a species that fits the profile of the killer– its a mosasaur specialized to victimize other marine reptiles. Thats most likely not a coincidence.”
Thalassotitan was a risk to everything in the oceans– consisting of other Thalassotitan. The huge mosasaurs bear injuries sustained in violent fight with other mosasaurs, with injuries to their face and jaws sustained in fights. Other mosasaurs show similar injuries, however in Thalassotitan these injuries were extremely common, showing frequent, intense fights over feeding premises or mates.
” Thalassotitan was a remarkable, scary animal,” said Dr. Nick Longrich, who led the study. “Imagine a Komodo Dragon crossed with an excellent white shark crossed with a T. rex crossed with a killer whale.”
Map of distribution of Thalassotitan. Credit: Nick Longrich
The new mosasaur lived in the final million years of the Age of Dinosaurs, a contemporary of animals like T. rex and Triceratops. Together with current discoveries of mosasaurs from Morocco, it suggests that mosasaurs werent in decrease before the asteroid impact that drove the Cretaceous mass termination. Rather, they flourished.
Teacher Nour-Eddine Jalil, a co-author on the paper from the Museum of Natural History in Paris, said: “The phosphate fossils of Morocco use an unparalleled window on the paleobiodiversity at the end of Cretaceous.
” They tell us how life was varied and abundant prior to the end of the dinosaur period, where animals had to specialize to have a place in their communities. Thalassotitan completes the picture by taking on the function of the megapredator at the top of the food chain.”
” Theres so much more to be done,” said Longrich. “Morocco has among the wealthiest and most diverse marine faunas known from the Cretaceous. Were just getting started understanding the diversity and the biology of the mosasaurs.”
Dr. Longrich has actually composed a blog site about the research study here: https://www.nicklongrich.com/blog/thalassotitan-the-killer-mosasaur
Recommendation: “Thalassotitan atrox, a huge predatory mosasaurid (Squamata) from the Upper Maastrichtian Phosphates of Morocco” by Nicholas R. Longrich,Nour-Eddine Jalil, Fatima Khaldoune, Oussama Khadiri Yazami, Xabier Pereda-Suberbiola and Nathalie Bardet, 24 August 2022, Cretaceous Research.DOI: 10.1016/ j.cretres.2022.105315.

Artists representation of Thalassotitan atrox. Credit: Andrey Atuchin
Paleontologists have actually found a substantial new mosasaur from Morocco, named Thalassotitan atrox, which filled the apex predator specific niche. With huge jaws and teeth like those of killer whales, Thalassotitan hunted other marine reptiles– plesiosaurs, sea turtles, and other mosasaurs.
Sea monsters truly existed at the end of the Cretaceous duration, 66 million years earlier. While dinosaurs thrived on land, massive marine reptiles called mosasaurs ruled the seas.
Mosasaurs werent in fact dinosaurs, however massive marine lizards growing up to 12 meters (40 feet) in length. They were far-off family members of modern iguanas and monitor lizards.

The new mosasaur, named Thalassotitan atrox, evolved to prey on all the other marine reptiles.
Those fed little fish, feeding bigger fish, which fed mosasaurs and plesiosaurs– and so on, with these marine reptiles becoming food for the enormous, carnivorous Thalassotitan.
Many mosasaurs had long jaws and slim teeth for capturing fish, but Thalassotitan had a brief, wide muzzle and enormous, cone-shaped teeth like those of an orca. Thalassotitan was a risk to whatever in the oceans– including other Thalassotitan. Other mosasaurs show similar injuries, but in Thalassotitan these injuries were incredibly common, suggesting regular, intense fights over feeding grounds or mates.