Mosasaur fossil with bizarre screwdriver teeth found in Morocco – ScienceDaily


Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, that had strange, ridged teeth unlike those of any known reptile. Together with other recent discoveries from Africa, they indicate that mosasaurs and other marine reptiles were evolving rapidly even 66 million years ago, when an asteroid wiped them out along with the dinosaurs and about 90% of all species on Earth.

new species, Stelladens mysteriosusIt comes from late Cretaceous Morocco and was about twice the size of a dolphin.

It had a unique tooth arrangement with blade-like edges hanging over the teeth, arranged in a star-shaped pattern, reminiscent of a cross-head screwdriver.

Most mosasaurs had two blade-like serrated edges on the front and back of the tooth to help cut prey. stladens It had anywhere from four to six of these blades flush against the teeth.

“It’s a surprise,” said Dr Nick Longrich of the University of Bath’s Milner Center for Evolution, who led the study. “It’s not like any mosasaur, or any reptile, even any vertebrate we’ve seen before.”

“I’ve worked on Mosasaurs in Morocco for over 20 years, and I’ve never seen anything like it – I’ve both been baffled and amazed!” said Dr. Nathalie Bardet, a marine reptile specialist from the Museum of Natural History in Paris.

Several teeth were found with the same shape indicating that their strange shape was not the result of pathology or mutation.

Unique teeth indicate a specialized feeding strategy, or specialized diet, but it remains unclear what exactly stladens food.

Dr Longrich said: “We have no idea what this animal ate, because we know of nothing similar either alive today or from the fossil record.

It could have found a unique way of feeding, or it could have been filling an ecological niche that doesn’t exist today. The teeth look like the head of a Phillips screwdriver, or perhaps a hex wrench.

“So what’s he eating? Phillips head screws? IKEA furniture? Who knows.”

The teeth were small, but stout and frayed at the tips, which would seem to rule out thin-bodied prey. However, the teeth were not strong enough to crush heavily armored animals such as clams or sea urchins.

“This might seem to indicate that she’s eating something small and lightly armored — a thin-skinned ammonia, crustacean or bony fish — but it’s hard to tell,” Longrich said. “There were strange animals living in the Cretaceous period — ammonites, belemnites, bacolites — that no longer existed. This mosasaur probably ate something, took up space, that just didn’t exist anymore, and that might explain why no such thing ever existed. once again.

“Evolution is always unpredictable. Sometimes it goes off in a unique direction, something never seen before evolves, and then it never evolves again.”

Mosasaurs lived alongside dinosaurs, but they were not dinosaurs. Instead, they were giant lizards, relatives of Komodo dragons, snakes, and iguanas, adapted to life at sea.

Mosasaurs evolved about 100 million years ago, diversifying until 66 million years ago, when a giant asteroid hit Mexico’s Yucatan Peninsula, plunging the world into darkness.

Although scientists have debated the role of environmental changes at the end of the Cretaceous period in the extinction, stladensalong with recent finds from Morocco, suggest that mosasaurs were evolving rapidly until the end—they peaked out, rather than died out.

The new study shows that even after years of work in Morocco’s Cretaceous period, new species keep being discovered. The reason may be that most species are rare.

The study authors predict that in an ecosystem so diverse it could take decades to find all of the rare species.

“We’re not even close to finding everything in this family,” Longrich said, “This is the third new species to appear, just this year. The amount of diversity at the end of the Cretaceous is staggering.”

Noureddine Jalil, professor at the Museum of Natural History and researcher at Cadi Ayyad University in Morocco, said: “Animals have produced an incredible number of surprises – a mosasaur with teeth arranged like a saw, a turtle with a snout in the shape of a snorkel, many vertebrates of various shapes and sizes.” , and now a mosasaur with star-shaped teeth.

We used to say the work of an artist full of imagination.

“The Moroccan sites provide an unparalleled picture of the amazing biodiversity before the Great Crisis at the end of the Cretaceous period.”


Source link

Related Posts