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World’s Biggest Arctic Mission Just Returned Home, And The Discoveries Are Chilling

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The German Alfred Wegener Institute’s Polarstern ship returned to the port of Bremerhaven after 389 days spent drifting through the Arctic trapped in ice, allowing scientists to gather vital information on the effects of global warming in the region.

 

Mission leader Markus Rex said he and his team of 300 scientists from 20 countries had witnessed “a place of truly fascinating and unique beauty”.

“We should really make every effort to preserve this world… for future generations and to use the small chance we still have to do so,” he told a press conference.

Ahead of their return, Rex told AFP the scientists had seen for themselves the dramatic effects of global warming on ice in the region considered “the epicentre of climate change“.

“We witnessed how the Arctic ocean is dying,” Rex said. “We saw this process right outside our windows, or when we walked on the brittle ice.”

Underlining how much of the sea ice has melted away, Rex said the mission was able to sail through large patches of open water, “sometimes stretching as far as the horizon”.

“At the North Pole itself, we found badly eroded, melted, thin and brittle ice.”

‘Ice-free Arctic’

If the warming trend in the North Pole continues, in a few decades we will have “an ice-free Arctic in the summer”, Rex said.

The Polarstern mission, dubbed MOSAIC, spent more than a year collecting data on the atmosphere, ocean, sea ice and ecosystems to help assess the impact of climate change on the region and the world.

 

To carry out the research, four observational sites were set up on the sea ice in a radius of up to 40 kilometres (25 miles) around the ship.

The researchers collected water samples from beneath the ice during the polar night to study plant plankton and bacteria and better understand how the marine ecosystem functions under extreme conditions.

The 140-million-euro (US$165 million) expedition has also brought back 150 terabytes of data and more than 1,000 ice samples.

The team measured more than 100 parameters almost continuously throughout the year and are hoping the information will provide a “breakthrough in understanding the Arctic and climate system”, Rex said.

Thomas Krumpen, sea ice physicist said: “For us the second phase is starting – the analysis of data. A lot of data has returned with the ship and we will likely be busy with it over the next ten years.”

The multitude of parameters will feed into the development of models to help predict what heatwaves, heavy rains or storms could look like in 20, 50 or 100 years.

60 polar bears

Since the ship departed from Tromso in Norway on 20 September 2019, the crew have seen long months of complete darkness, temperatures as low as -39.5 Celsius (-39.1 Fahrenheit) – and more than 60 polar bears.

A shot had to be fired to warn off a polar bear that came too close.

 

But the bigger threat was the coronavirus pandemic in the spring, which left the crew stranded at the North Pole for two months.

A multinational team of scientists was scheduled to fly in as part of a scheduled relay to relieve those who had already spent several months on the ice, but the plan had to be redrawn when flights were cancelled across the world as governments scrambled to halt the spread of the coronavirus.

During the course of the expedition, the German ship zigzagged through 3,400 kilometres of ice along a wind-driven route known as the transpolar drift.

The voyage was a huge logistical challenge, not least when it came to feeding the crew – during the first three months, the ship’s cargo included 14,000 eggs, 2,000 litres of milk and 200 kilograms of rutabaga, a root vegetable.

Radiance Calmer, a researcher at the University of Colorado who was on board the Polarstern from June to September, told AFP that stepping out on to the ice was a “magical” moment.

“If you concentrate, you can feel it moving,” she said.

© Agence France-Presse



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Fossil Footprints Show a Dinosaur as Big as a T. Rex Once Terrorised Australia

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Perhaps the most iconic dinosaur is Tyrannosaurus rex, a massive predator that lived in what is now North America.

We have now discovered that carnivorous dinosaurs of a similar size existed in ancient Australia as well.

 

Following the footprints

We learned about these carnivores by studying fossils that were discovered up to 90 years ago. Coal miners came across them while digging in the Walloon Coal Measures at Rosewood, near Ipswich and Oakey, north of Toowoomba, Queensland.

The fossils are not bones. They are fossilised footprints, the only form of fossils that record the movements of animals and preserve details of their behaviour and environments they preferred.

While searching through records of fossil footprints in Australia, we came across an archival photograph from the 1930s showing a dinosaur footprint inside a coal mine.

While these mines have long since closed, the picture led us to investigate fossil footprints collected at that time and stored in museums, and other footprints like them.

Older than T. rex

The specimens we found suggest the richly forested and swampy environment of southern Queensland in the Jurassic Period was home to several types of meat-eating dinosaurs.

The smallest would have been the size of an emu, while the largest would have been just under 3 metres tall, almost as large and as imposing as a T. rex.

 

The footprint of this large dinosaur is almost 80 centimeters (31 inches) long – roughly the distance from the centre of your body to the tip of your outstretched arm. The fossilised track is approximately 160 million years old, 90 million years older than the oldest known T. rex fossils.

This suggests the print belongs to a different predatory dinosaur. While similar to T. rex in size and dietary preference, these massive ancient Australian trackmakers may have been slimmer and more elongated in appearance than the North American dinosaur icon.

file 20200618 41209 14xpdx2Photograph and a false-colour image showing the depth of one of the footprints. (Anthony Romilio)

Fast runners, formidable predators

As well as individual footprints, we found evidence of trackways where multiple footprints made by the same animal are preserved. Based on what we know about how two-legged animals move, we can use the trackways to figure out how the dinosaurs travelled through their environment.

Several of the larger dinosaurs seem to have been moving at a walking pace, as the lengths of their steps are shorter than the estimated lengths of their legs. However, two trackways had the very large step sizes that are typical of animals on the run.

 

The step distance suggests these large dinosaurs were moving at speeds of up to 35 kilometres (22 miles) per hour. For comparison, the average human can sprint at around 24 kilometres (15 miles) per hour.

These speeds mean the ancient track-makers would have been formidable predators. Unfortunately, no trackway was preserved for the largest track-maker.

Lucky conditions

Not all kinds of ground are equally suited to preserving tracks for fossilisation. What appears to have happened in southern Queensland is the dinosaurs stepped onto mats of swamp plant material that was then overlaid with sand, which results in sandstone filled footprints in a bed of coal.

The miners were able to easily remove the softer coal from beneath the sandstone, and to their surprise found these ancient footprints.

If not for the mining of coal and the keen eyes of the 20th century miners who spotted unusual features in the rock, we might never have known about these tracks. It is likely that more hidden treasures are still buried beneath our feet.

Filling in the gaps in ancient Australia

Our discovery fills a gap in the slowly growing record of Australian dinosaurs. While large dinosaur tracks have been documented in various Australian states, so far most belong to plant-eaters.

They include tracks of long-necked sauropods similar to Brontosaurus, and ornithopods similar as Muttaburrasaurus, the skeleton of which can be seen on display at the Queensland Museum.

Evidence for meat-eating dinosaurs also exists, but so far the fossil record indicated much smaller animals, ranging from the size of chickens to a little bit smaller than Allosaurus.

Our discovery of the footprints of a huge carnivore adds an important top-level predator to the Australian dinosaur-scape.The Conversation

Anthony Romilio, PhD, Independent Researcher, The University of Queensland and Steven W. Salisbury, PhD; Senior Lecturer, School of Biological Sciences, The University of Queensland.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 



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T. Rex Really Could Crush a Car in Its Jaws, Without Damaging Its Own Skull

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The Tyrannosaurus rex had the strongest bite of any known land animal – extinct or otherwise.

The king of the dinosaurs was capable of biting through solid bone, but paleontologists had long been baffled as to how it accomplished this feat without breaking its own skull.

 

In a new study published in the journal The Anatomical Record, researchers found that the T. rex had a rigid skull, like those of modern-day crocodiles and hyenas, rather than a flexible one like birds and reptiles. That rigidity enabled the dinosaur to bite down on its hapless prey with a force upwards of 7 tons.

“The highest forces we estimated in T. rex were just shy of 64,000 Newtons, which is about 6.5 metric tonnes (7.1 tons) of force,” Ian Cost, the lead author of the new study, told Business Insider.

Modern-day saltwater crocodiles, which hold the chomping record for any living animal, clamp down with a force of 16,460 newtons – only about 25 percent as strong as a T. rex’s bite.

(Illustration by Zhao Chuang/courtesy of PNSO)(Illustration by Zhao Chuang, courtesy of PNSO)

Scientists weren’t sure whether T. rex skulls were flexible or rigid

Previously, scientists had suggested that the T. rex’s roughly 6-foot-long (1.8-metre), 4-foot-tall (1.2 metre) skull had flexible joints – a characteristic called cranial kinesis.

Some creatures need to have parts of their skull moving different directions at once, and independently of their jaws. Snakes that swallow animals whole, or birds that have to nibble awkwardly-shaped foods, benefit from having a mobile skull.

 

Paleontologists first hypothesised that T. rex might also have benefited from mobile joints, moving its skull bones around to help bite with full force.

But Cost said that thinking didn’t align with what scientists observed in modern-day predators like crocodiles and hyenas, which leverage the greatest bite forces of any animals alive today. Crocs’ skulls are very rigid, with little to no cranial kinesis.

So Cost’s group modelled how parrots’ and geckos’ skulls and jaws – two animals with mobile skulls – worked, and then applied those movements to a T. rex skull.

“What we found was that the skull of T. rex actually does not react well to being moved around and prefers to not move,” Cost said.

According to Casey Holliday, a co-author of the study, there’s a trade-off between movement and stability when a creature bites down with a lot of force.

“Birds and lizards have more movement but less stability,” he said in a press release.

Less bite stability and range of motion limits the amount of bite force an animal can muster.

3D map of <em>T. rex</em> skull showing muscle activation. (Courtesy of Eric Stann/University of Missouri)3D map of T. rex skull showing muscle activation. (Courtesy of Eric Stann/University of Missouri)

T. rex jaws could crush a car, as the Hollywood monster does in Jurassic Park

Mark Norell, a curator at the American Museum of Natural History, has described the T. rex as “a head hunter”, since the predator had the rare ability to bite through solid bone and digest it.

Paleontologists know this from the dinosaur’s fossilized poop; they have discovered T. rex faeces containing tiny chunks of bone eroded by stomach acid.

 

According to Cost, a rigid skull enabled the T. rex to bite through bone. That’s how the dinosaur was “capable of producing enough force to crush some cars, but maybe not every car.”

He added that funelling the T. rex’s 7.1 tons of bite force “through a tooth or two at impact results in incredible pounds per square inch of pressure that could puncture-crush many vehicles, Jeep tires included.”

In the 1993 Hollywood blockbuster, Jurassic Park, a T. rex escapes its paddock and attacks two Jeeps that have broken down nearby. The predator, hoping to nibble on two kids trapped inside the car, flips one Jeep upside down and proceeds to bite into the vehicle’s undercarriage, puncturing a tire.

But the T. rex wasn’t the only Cretaceous-era dinosaur to have an immobile skull, Holliday told Business Insider.

The Triceratops and Ankylosaurs also had fixed, akinetic skulls. Plus, some close relatives of the T. rex, including Oviraptors and Therizinosaurs, don’t have the features that suggest they had flexible skulls, either.

Key features of a stiff <em>T. rex</em> skull. (University of Missouri)Key features of a stiff T. rex skull. (University of Missouri)

Was the T. rex was a hunter, scavenger, or both?

According to experts at the American Museum of Natural History, the T. rex was a cannibal. But scientists don’t know whether the dinosaurs killed one another or just ate T. rexes that were already dead.

When it comes to the dinosaur’s other dietary preferences, arguments persist about whether the dinosaur was a hunter or a scavenger.

 

“A bulk of the evidence points to T. rex being a predator, not a scavenger,” Gregory Erickson, a paleontologist from Florida State University, previously told Business Insider. “It was a hunter, day in and day out.”

Cost said his study results, which indicate the T. rex’s skull handled prey in a similar way to a hyena’s, could shed some light on the debate.

“Hyenas, we know, are both hunters and scavengers,” he said. “I think, if anything, that T. rex was both a hunter and an opportunistic scavenger.”

This article was originally published by Business Insider.

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The Mystery of Bizarre Holes in T. Rex’s Head Might Finally Be Solved

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Despite its popular image of teeth and claws and thunder, Tyrannosaurus rex was no hot-head. New research indicates that the two mysterious holes in the top of the dinosaur’s skull likely helped regulate temperatures inside its head.

 

Previously, these holes – called the dorsotemporal fenestra – were thought to be filled with muscles that helped operate the powerful jaw. But, according to anatomist Casey Holliday of the University of Missouri, something didn’t quite add up.

“It’s really weird for a muscle to come up from the jaw, make a 90-degree turn, and go along the roof of the skull,” he said.

“Yet, we now have a lot of compelling evidence for blood vessels in this area, based on our work with alligators and other reptiles.”

Similar fenestra can be found in the skulls of a class of animals known as diapsids, grouped together because of this feature. This class includes not only crocodilians, but also birds, lizards, and tuatara; the holes are thought to have evolved about 300 million years ago.

Fenestra are not found in all dinosaur skulls, but those that do have them include tyrannosaurs and pterosaurs. To start figuring out what these holes were for, the team analysed different diapsid skulls to determine which ones had fenestra most similar to T. rex; the closest similarities turned out to be with crocodilians.

 

So, Holliday and his co-authors – William Porter and Lawrence Witmer from Ohio University, and Kent Vliet of the University of Florida – took thermal imaging cameras and went to study a bunch of alligators at the St Augustine Alligator Farm Zoological Park.

Because alligators are cold-blooded, or ectothermic, their body temperature is dependent on the temperature of their environment. This means that their thermoregulation processes are very different from warm-blooded, or endothermic, organisms.

“We noticed when it was cooler and the alligators are trying to warm up, our thermal imaging showed big hot spots in these holes in the roof of their skull, indicating a rise in temperature,” Vliet said.

“Yet, later in the day when it’s warmer, the holes appear dark, like they were turned off to keep cool. This is consistent with prior evidence that alligators have a cross-current circulatory system – or an internal thermostat, so to speak.”

glowcroc(Holliday et al., The Anatomical Record, 2019)

It’s not yet known whether dinosaurs in general, and T. rex in particular, were ectothermic or endothermic.

The topic is actually hotly debated, with some scientists thinking the former, some the latter, and some believing dinosaurs fell somewhere between the two – a feature called mesothermy. Previous research has suggested that the armoured ankylosaur had “crazy straw” tunnels in its skull to help keep its brain at optimum temperatures.

 

Now this research suggests that T. rex (and other dinosaurs) use some of the thermoregulation tactics of ectotherms, but what that actually means within the broader context of their metabolisms is yet to be explored.

What the scientists can tell, based on this research, is that there are no osteological features on the skull of the tyrannosaurus that indicate the fenestra were sites of muscle attachment. They can also infer, based on modern alligators, that the fenestra could have been used to regulate temperature in the T. rex‘s skull, by warming or cooling the blood that flows through blood vessels in the structures.

“We know that, similarly to the T. rex, alligators have holes on the roof of their skulls, and they are filled with blood vessels,” Witmer said.

“Yet, for over 100 years we’ve been putting muscles into a similar space with dinosaurs. By using some anatomy and physiology of current animals, we can show that we can overturn those early hypotheses about the anatomy of this part of the T. rex‘s skull.”

The team’s research has been published in The Anatomical Record.

 



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This Adorable Little Tyrannosaur Just Filled a Large Gap in T. rex Evolution

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Two tiny tyrannosaurid skeletons have just filled in the fossil record, elucidating the humble origins of the Cretaceous’ mightiest predator, Tyrannosaurus rex.

Dating back to around 92 million years ago, the two tyrannosaurs hail from the Zuni Basin in New Mexico. They stood just 1 metre (3 feet) tall and have been named Suskityrannus hazelae.

 

“This taxon, S. hazelae [..], is a small-bodied species phylogenetically intermediate between the oldest, smallest tyrannosauroids and the gigantic, last-surviving tyrannosaurids,” the researchers wrote in their paper.

The large tyrannosaurs appeared on the scene in the Late Cretaceous, about 81 million years ago. Prior to that, there had been some medium-sized tyrannosaurids up to about 150 million years ago, but the fossil record was shockingly sparse for the 70 million years in between.

Palaeontologists think this is the result of high sea levels that flooded the continents, eroding sediment and decreasing the potential for bones to be preserved.

Whatever the reason, it’s been a spanner in the works for uncovering the evolutionary history of the mighty T. rex. But now some tyrannosaurid bones from those dark ages are starting to be uncovered – confirming that the great hunters could have emerged from smaller ancestors.

A ‘missing link’ tyrannosaur called Timurlengia euotica from 90 million years ago was recently found in Uzbekistan. It was about the size of a horse.

Another, dating back 96 million years ago, was just described in a paper earlier this year. Moros intrepidus was a little smaller than a kangaroo, and ran around what is now Utah.

 

Including S. hazelae, these three species are all from the Middle Cretaceous, which makes them unlikely to be direct ancestors of T. rex. Instead, palaeontologists believe all these animals diverged from a common ancestor sometime in the Early Cretaceous, which ended roughly 100 million years ago.

The S. hazelae skeletons recovered show a tyrannosaurid that was about coyote-sized (hence the name – suski is the Zuni word for coyote), weighing no more than between 20 and 40 kilograms (44 to 88 pounds). Its skull was between 25 and 32 centimetres in length (10 to 12.5 inches), and its entire body was just a little bigger than the mere skull of a T. rex.

s hawelae t rex skill(Sterling Nesbitt/Virginia Tech)

Both skeletons were juveniles, so it’s possible they would have grown a little bigger, but probably not by much – the palaeontologists believe these pipsqueaks where already teenagers.

S. hazelae certainly wouldn’t have reached the 5,000 to 7,000 kilogram (11,000 to 15,500 pound) weight class of T. rex, whose rapid gain in size remains to be something of a mystery.

But despite its small size, the tiny tyrannosaur was no slouch. Its jaw indicates that it would have had a very strong bite, like the later tyrannosaurs; other features show it was fleet of foot, like the earlier ones. S. hazelae, somewhere in the middle, could hold its own.

 

And it has big significance, too. By filling in the fossil record, it could help palaeontologists figure out why tyrannosaurids changed so dramatically, and so fast.

“It is unclear why these animals were drastically changing so many aspects of their anatomy and biology during the mid-Cretaceous. This may have been related to some of the environmental changes occurring during this time, although the sparse fossil record makes this difficult to test,” the researchers wrote in their paper.

“Alternatively, these developments may have been adaptations for hunting at medium size, in ecosystems where late-surviving allosauroids remained incumbent in the top predator niche earlier in the Cretaceous.”

The research has been published in Nature Ecology & Evolution.

 



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Palaeontologists in Canada Discover The Biggest T. rex Yet, And It’s Epic

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We all knew the mighty Tyrannosaurus rex was big. But palaeontologists in Canada have just identified the biggest lizard tyrant king yet – its name is Scotty, and boy was it a corker.

 

From nose to tail-tip, Scotty measures 13 metres (43 feet), and would have cracked the scales at 8,800 kilograms (19,400 pounds), based on a calculation using its mighty thigh-bones.

“This is the rex of rexes,” said palaeontologist Scott Persons of the University of Alberta in Canada.

“There is considerable size variability among Tyrannosaurus. Some individuals were lankier than others and some were more robust. Scotty exemplifies the robust. [It] comes out a bit heftier than other T. rex specimens.”

The bones are not actually new. They were discovered in Saskatchewan in 1991, but since they were embedded in some pretty solid sandstone, the excavation was a slow and painstaking process, taking over a decade.

Then palaeontologists had to put the bones back together – another slow and painstaking process. But it was worth it, because now those bones are finally giving up their secrets.

For instance, we know that Scotty (named for the bottle of Scotch whisky opened to celebrate the skeleton’s initial discovery) was exceptionally old – it has lived longer than any other T. rex discovered to date.

 

Palaeontologists can figure this out by looking at a dinosaur’s bones. Annual variations in climate and food availability would slow dinosaurs’ bone growth, which results in a ring. These rings – much like the rings of a tree trunk – can be counted to estimate a dinosaur’s age of death.

It was thought that T. rex had a lifespan of around 30 years; the previous oldest ever found, Trix, had an estimated age of about 30.

Scotty had a year or two on Trix – it died in its early 30s. “By Tyrannosaurus standards,” Persons said, “it had an unusually long life.”

Scotty’s bones also had extensive injuries that showed signs of healing. Which means the old animal who lived 66 million years ago in the Cretaceous, got into a lot of scrapes – and somehow survived them.

The injuries include broken ribs, an infection in the dino’s jaw, and marks on its tail that could be from a bite inflicted by another T. rex in an epic battle.

It may come from somewhat teeny tiny origins, but there’s a reason T. rex became one of the most beloved extinct animals to have ever trod Earth. As Scotty demonstrates, it was a formidable beast indeed.

“I think there will always be bigger discoveries to be made,” said Persons. “But as of right now, this particular Tyrannosaurus is the largest terrestrial predator known to science.”

The research has been published in The Anatomical Record.

 



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Incredible New Reconstruction Shows Baby T. Rex Could Have Been The Cutest Floof Monster

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Teeth-rattling roars. Earth-shaking stomps. Teeth as long as your forearm. Claws as big as your hand. The mighty Cretaceous king of the ‘tyrant lizards’, Tyrannosaurus rex – and isn’t it just the most adorable thing you have ever seen?

 

Okay, this obviously isn’t a real video of a baby T. rex. It’s a reconstruction by palaeontologists at the American Museum of Natural History, showing what they think the wee things might have looked like: like a fluffy little baby bird with tiny chompers.

Historically, tyrannosaurids (the family of theropod dinosaurs to which T. rex belongs) have been depicted like reptiles, with rough, scaly skin. Although in recent years evidence has surfaced that some earlier tyrannosaurids were feathered, fossilised skin impressions from T. rex show little to no evidence of feathers.

Palaeontologists believe they may have been partially feathered, around the neck area. And because dinosaurs resemble birds in quite a few ways, feathers are definitely plausible.

Although we don’t have a lot of baby T. rex remains to study, it’s not impossible that they hatched with baby fluff to keep their little growing bodies warm, as well as camouflaged for safety.

As they grew, and their skins thickened, perhaps they wouldn’t have needed their camouflage feathers any more – after all, there weren’t a lot of predators in the Cretaceous that could take on a T. rex, so it didn’t really need to hide.

 

It’s possible we’ll never know; maybe baby T. rexes were naked and scrawny, like a hatchling songbird, instead of already covered in feathers as they emerge from the egg, like a chicken or an ostrich.

Given that the closest relatives of T. rex that are alive today are chickens and ostriches (and let’s not forget the time scientists strapped plungers to chicken butts to study how theropods walked), we know which one we’d be banking on.

The baby T. rex was constructed as part of the American Museum of Natural History’s big exhibition focusing entirely on the dinosaur, T. rex: The Ultimate Predator, which opens on Monday, 11 March and closes on 9 August 2020.

 



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Turns Out The Fearsome T. Rex Evolved From a Ridiculously Tiny Ancestor

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Is there any dinosaur more iconic than Tyrannosaurus Rex? Its mighty jaws and fierce mien ignite the imaginations of four-year-olds everywhere. It’s the dinosaur poster child – yet this fearsome beast’s beginnings were, new evidence suggests, quite humble.

 

How humble? Well, a little smaller than a kangaroo, as we now know from a newly discovered T. rex ancestor. And the wee beastie, which hails back to the Cretaceous 96 million years ago from what is now Utah, is helping close a 70-million-year gap in the T. rex fossil record.

Its name is delightful: Moros intrepidus. It was named after Greek god Moros, who represents impending doom; and the word intrepid, because its ancestors originated in another continent.

So a rough translation would be “Adventurous Doombringer” – isn’t that just the best dinosaur name you’ve ever heard?

It’s the first tyrannosaur to have been found from its time period. We have earlier evidence of medium-sized, primitive tyrannosaurs on the North American continent dating back to the Jurassic, about 150 million years ago. But they were overshadowed by allosaurus – bigger and tougher, the top predator of the day.

So there’s this gap until around 81 million years ago, during the Cretaceous, when big T. rex emerged (although a ‘missing link’ tyrannosaur called Timurlengia euotica from 90 million years ago was recently found in Uzbekistan).

 

This issue has been eating away at palaeontologists (pun intended).

So palaeontologist Lindsay Zanno of North Carolina State University mounted an expedition to search for them – and, after 10 years, they found teeth and a hind leg that ended up belonging to the previously unknown M. intrepidus.

Interestingly, its teeth showed similarities to teeth from Asian tyrannosaurs – evidence that the little Doombringer’s ancestors had made its way to North America from the Asian continent via a Beringian land bridge, at least 30 million years prior.

The dino was titchy. It was nearly fully grown – six or seven years old when it died – but it stood just 90-120 centimetres (3-4 feet) at the hip, and weighed just 78 kilograms (172 pounds) or thereabouts.

The size is a far cry from its late Cretaceous descendants, which clocked in at between 5,000 and 7,000 kilograms (11,000 to 15,500 pounds), but that doesn’t mean M. intrepidus was a limp fish.

Moros was lightweight and exceptionally fast. These adaptations, together with advanced sensory capabilities, are the mark of a formidable predator. It could easily have run down prey, while avoiding confrontation with the top predators of the day,” Zanno said.

 

So, as the allosaur declined, the tiny little tyrannosaur used its speed and size to its advantage, working its way up from zero to hero – or “wallflower to prom king,” as Zanno put it.

“Although the earliest Cretaceous tyrannosaurs were small, their predatory specialisations meant that they were primed to take advantage of new opportunities when warming temperatures, rising sea-level and shrinking ranges restructured ecosystems at the beginning of the Late Cretaceous,” she said.

“We now know it took them less than 15 million years to rise to power.”

Don’t mess with tyrannosaurs, you guys.

The team’s research has been published in the journal Communications Biology.

 



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