nandi's blog

Utahraptor: A State Mascot?

Monday, February 25, 2019

The Senate approved a proposition to christen Utahraptor as the Utah State Dinosaur. but it was decided to be a recognized insignia of the state instead. Photo: Zach Tirrell / CC BY-SA 2.0

The Senate approved a proposition to christen Utahraptor as the Utah State Dinosaur. but it was decided to be a recognized insignia of the state instead.

The marquee fossil of the state and the largest Dromaeosaur (popularly known as raptor) known to date, Utahraptor, a genus of its own, was discovered in 1975 by Jim Jensen in the Dalton Wells Quarry in east central Utah near the town of Moab. However, this discovery remained incipient and largely unattended to, and it was only following a discovery of a large foot claw in late 1991 when large-scale excavations were undertaken by the eminent paleontologist James Kirkland in the Gaston Quarry in Grand County, in the reputedly fossil-rich Cedar Mountain Formation. It’s widely speculated that, this ton-hefty behemoth — similar to its sibling and cousin species, being the predecessor of birds — had body (axillary) feathers, though any substantial proof is yet to be unearthed.

The formal type specimen, CEU 184v.86, is currently housed at the College of Eastern Utah Prehistoric Museum while Brigham Young University, the repository to Jensen’s excavations, possesses the largest collection of Utahraptor fossilised remains and finds.

Formally consecrated as Utahraptor ostrommaysorum, honoring Dr. John Ostrom of Yale University for his pioneering research linking carnivorous dinosaurs to the ancestry of birds, it was originally to be christened Utahraptor spielbergi to honor a prospective donation courted of “Jurassic Park” director Steven Spielberg, which could never come to fruition due to inconclusive negotiation.

Kirkland postulated that Utahraptors attempted to take advantage of vulnerable prey trapped in quagmires and bogs or scavenge upon the carrion thereof, themselves becoming mired in the quicksand, resulting in the fossilized carnal remains in the form of the predator traps he observed in 2001 in sandstone boulders in eastern Utah, and later in Cleveland-Lloyd Quarry and the La Brea tar pits of California. The Utahraptor’s find flung open gates to new avenues of palao-anatomic inquiry by serving to debunk the preconceived notion that sickle-clawed raptors were sleek, supple, diminutive creatures. This special specimen compelled them not only to reconsider their hypothesis but to overhaul it altogether.

Being the oldest and largest member of its family, the tantalizingly bulky yet agile beast’s large, retractable sickle claw-toe, the salient characteristic of the family, itself measured 10 inches and served to rip apart the hide and expose the innards and entrails of its prey.

In testimony to the enigmatic beast’s modern cultural significance, the Senate approved a proposition to christen Utahraptor as the Utah State Dinosaur. However, Utahraptor would have replaced another dinosaur, the Allosaurus, as the state’s official fossil, so it was decided that Utahraptor would be another recognized insignia of the state.

Fresh investigations continue to be opened every once a while and unveil novel insights into its elusive physiology. Being the forerunner of birds, the tantalizing bulk of this titan poses an elusive dilemma and inspires awe for evolutionary biologists.

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Were Dinosaurs Killed Off by Asteroid or Volcanoes? It's Complicated

Sunday, February 24, 2019

Dinosaur skeletons on display at Tokyo's Science Museum

Every school child knows the dinosaurs were killed off by an asteroid smashing into the Earth some 66 million years ago.

But scientists say the story may not be quite that simple, and that massive volcanic eruptions over hundreds of thousands of years may have contributed to the dinosaurs' demise at the end of the Cretaceous period.

Two studies published in the journal Science contributed to a longstanding scientific debate about what exactly finished off the mighty reptiles.

Before the 1980s, the dominant theory had been that huge and prolonged volcanic eruptions caused a rapid and deadly shift in the planet's climate by sending vast clouds of ash, gas and dust into the atmosphere.

Then scientists discovered the huge Chicxulub crater of an ancient asteroid impact off the Caribbean coast of Mexico, which they posited had sent so much debris into the atmosphere that it hampered photosynthesis in plants and killed off three-quarters of life on Earth.

Ever since, scientists have maintained a lively debate about the relative contribution of each cataclysmic event to the mass die-off.

The authors of the two reports published Thursday were able to date massive lava flows with far greater precision, whittling it down from around a million years to a period of tens of thousands of years.

"We are able to recreate with great precision the order of events at the end of the Cretaceous period," Loyc Vanderkluysen, a professor of geoscience at Drexel University in Philadelphia, told AFP.

He was part of a team that dated the vast lava flows known as the Deccan Traps in India using radiation measurements. The other team used a different dating method.

The expulsion of lava there over a million years left the Deccan flows more 1,200 meters (4,000 feet) thick in places today, a volume large enough to cover an area the size of France to a depth of several hundred meters, he said.

Graphic on the catastrophic events that wiped out large dinosaurs and many other species on the planet some 66 million years ago.

No coincidence

The new dating made by the two teams match up: one found that a "pulse" of volcanic eruptions occurred just before the mass extinction.

The other is less precise but suggests that the majority of lava flows came after the asteroid hit Earth, backing up the idea that the impact triggered an earthquake so massive it would have registered 11 on the moment magnitude scale, something never witnessed by humans.

That in turn set off a wave of volcanic eruptions that lasted some 300,000 years.

"That bolsters the theory that the impact was the main cause," said Vanderkluysen. "It's like shaking a bottle of Orangina, it can accelerate volcanic activity."

The close correlation of the two events—eruptions and extinction—is unlikely to be a coincidence, the researchers say.

Other periods of intense volcanic activity have coincided with mass extinction events said Blair Schoene, a professor of geosciences at Princeton and a co-author of the other study.

"The big question is, would the extinction have happened without the impact, given the volcanism, or conversely, would the extinction have happened without the volcanism, given the impact? I don't think we know that answer," he told AFP.

"The main take-home point is that it's not that simple. Nature is complicated," he added. "By studying both phenomenons in as much detail as possible, we can try and figure out what the whole story is."

Mapping the timeline of that long-ago mass extinction is crucial, Schoene said, to understanding the consequences of the current so-called "sixth extinction,' which humans are currently causing.


More information: C.J. Sprain el al., "The eruptive tempo of Deccan volcanism in relation to the Cretaceous-Paleogene boundary," Science (2019). … 1126/science.aav1446

B. Schoene el al., "U-Pb constraints on pulsed eruption of the Deccan Traps across the end-Cretaceous mass extinction," Science (2019).


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Scientists Are Still Confused About Dinosaur Extinction Causes

Sunday, February 24, 2019

New research from Berkeley research group reveals new questions about the mass-extinctions 60 million years ago.

A fresh study might change our knowledge about dinosaur extinction. A group of scientists at the University of California, Berkeley, published a paper in Science Magazine suggesting that an asteroid (or comet) impact in the Caribbean Sea 66 million years ago boosted the volcanic activity in India, the other side of the planet causing the calamity.

The scientists investigated samples from the so-called Deccan Traps lava flows, a result of million-years-long eruptions covering the surface with lava on a massive scale in India (500 kilometers across the continent, with nearly 2 kilometers thick).

It was known from prior research that the flows continued for about a million years, although, having scrutinized more samples from various locations, the new study claims that three-quarters of the lava erupted after the impact, countering the earlier claims saying that 80 percent of the lava flow occured before the impact.

Professor Paul Renne, director of the Berkeley Geochronology Center, one of the authors of the article says: "That is an important validation of the hypothesis that the impact renewed lava flows."

K-Pg boundary

Scientists found the period of worldwide mass extinctions to be at the end of the Cretaceous Period. We have long known that the simultaneous events of eruptions and the impact are responsible for killing off the dinosaurs (amongst other species). Where the new research challenges its predecessors is the effects the simultaneously happening catastrophes played on one another.

As co-author Courtney Sprain, a former Berkeley grad student summarizes the new information: "Either the Deccan eruptions did not play a role - which we think unlikely - or a lot of climate-modifying gases were erupted during the lowest volume pulse of the eruptions.”

Using three times more basalt samples, the team is confident that the eruptions happened at the same time in case of the whole continent, which proves their belief that it was triggered by the impact of the asteroid.

Volcanos vs asteroid, or volcanos and asteroid?

Volcanic activity releases a vast amount of gases into the atmosphere such as carbon dioxide, methane, sulfur, and aerosols. Although while some of them warm the planet, others cool it down. The impact of the asteroid, on the other hand, sends dust into the atmosphere which blocks the sun, thus, contributes to the cooling of the planet.

What exactly caused the extreme, eight degrees Celsius global warming in the K-Pg boundary then? Even the scientists seem a little confused, Sprain says: “Both the impact and Deccan volcanism can produce similar environmental effects, but these are occurring on vastly differing timescales, (…) Therefore, to understand how each agent contributed to the extinction event, assessing timing is key."

The fact that there is no flood basalt eruption happening makes it extremely hard to know the order of the gases emitted during this activity. Even the most recent one happened some fifteen million years ago by the Columbia River.

And here is another interesting fact just to make the whole story even more confusing. As Sprain noted, a research group from Princeton is publishing an article that aims to precisely date the Deccan Traps in the same issue of Science, however, there are major differences between the two groups’ results.

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Tiny Tyrannosaur Fossil Discovery Changes The Dinosaur Timeline

Friday, February 22, 2019

Tyrannosaurus Rex. Dean Mouhtaropoulos/Getty Images

Dinosaur fossil found in Utah.

Tyrannosaurus rex wasn't always the king of the dinosaurs. Before they became towering predators, tyrannosaurs started out much smaller, and a newly discovered fossil is helping fill the gap between those two extremes.

The fossil findings are detailed in a study published in Communications Biology.

The dinosaur fossil was found in Utah, where it lived 96 million years ago in a lush delta during the Cretaceous period. It's been named Moros intrepidus, which means "harbinger of doom." The dinosaur lived at the end of the allosaurs' reign at the top of the food chain and before Tyrannosaurus rex arrived.

It's now the oldest tyrannosaur from the Cretaceous period found in North America.

Medium-size tyrannosaur fossils have been found from the Jurassic period, about 150 million years ago. And then, about 81 million years ago during the Cretaceous, tyrannosaurs grew into giant predators and replaced allosaurs as the top of the food chain.

So what happened in between? Moros is helping researchers fill that 70 million-year gap, as well as provide a portrait of tyrannosaur lineage in North America. Moros links the earliest, smaller tyrannosaurs to Tyrannosaurus rex.

"With a lethal combination of bone-crunching bite forces, stereoscopic vision, rapid growth rates, and colossal size, tyrant dinosaurs reigned uncontested for 15 million years leading up to the end-Cretaceous extinction -- but it wasn't always that way," said Lindsay Zanno, lead study author and paleontologist at North Carolina State University, in a statement. "When and how quickly tyrannosaurs went from wallflower to prom king has been vexing paleontologists for a long time. The only way to attack this problem was to get out there and find more data on these rare animals."

Zanno and her team spent a decade searching for fossils from the Late Cretaceous period. They recovered teeth and a hind limb consisting of a femur, a tibia and parts of a foot belonging to Moros in the same area where Zanno found the fossil of a giant carnivorous carcharodontosaur.

But Moros stood between 3 and 4 feet tall. The dinosaur they found was 7 years old when it died, a nearly full-grown adult that would have weighed around 172 pounds. The elongated leg and foot bones indicated that it would be a great runner.

"Moros was lightweight and exceptionally fast," Zanno said. "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."

This allowed Moros to be a survivor as the environment shifted and changed. For 15 million years, tyrannosaurs were restricted to this smaller size before evolving into giants (about 12 feet tall and 11,000 to 15,500 pounds) over a 16 million-year period.

"Although the earliest Cretaceous tyrannosaurs were small, their predatory specializations 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," Zanno said. "We now know it took them less than 15 million years to rise to power."

Moros is most closely related to tyrannosaurs from Asia, which helped the researchers trace the dinosaurs' lineage. This means Moros crossed the Alaskan land bridge during the Early Cretaceous to reach North America.

"T. rex and its famous contemporaries such as Triceratops may be among our most beloved cultural icons, but we owe their existence to their intrepid ancestors who migrated here from Asia at least 30 million years prior," Zanno said. "Moros signals the establishment of the iconic Late Cretaceous ecosystems of North America."

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10 Terrific Dinosaur Books For Adults

Sunday, February 24, 2019

Artwork by Román García Mora

The continued success of the Jurassic Park franchise just goes to show that most of us never got over our childhood fascinations with our prehistoric pals the dinosaurs. The difference between now and then is that we can appreciate more of the mystery and the science than we could back then.  The books on this list will allow you to do a deep dive into the secret lives of dinosaurs, both factual and fictional. Here are 10 of the best dinosaur books for adults.

NOTE:  With the noteworthy exception of Paige Williams and The Dinosaur Artist, this list is made up of primarily white male authors. That seems to be most of what is available out there in terms of dinosaur books for adults. If you have any recommendations for books written by a more diverse group of writers, we’d love to hear them!




This is not your typical dinosaur book. It’s not written by a paleontologist. It’s a work of investigative journalism about the world of fossils and the lengths to which people will go in their quest to hold such a prominent piece of the past. This is the story of Erik Prokopi, a “super Tyrannosaurus” specimen (actually a T. Bataar), and the fierce custody battle that springs up when he tries to sell it at auction.


Called the “Best Dinosaur Biography” by Scientific American and rated one of the best Science books of 2018, The Rise and Fall of the Dinosaurs is the most up-to-date account of the age of dinosaurs out there. The book charts not only the history of dinosaurs on this planet, but also the work of Steve Brusatte, a young American paleontologist at the University of Edinburgh. It is an interesting, engaging, and highly educational read.


This book is an A to Z record of everything you have ever wanted to know about more than 300 dinosaur varieties. The information is pulled from many, many different sources – not just the annals of paleontology. Pim includes information on anatomy, astronomy, evolution, and mythology to complete the record.


John Pickrell, science writer and dinosaur enthusiast, traveled the world to find out about the newest, most interesting finds, including an aquatic crocodile-looking creature that was larger than a T-Rex found in North Africa and a creature with bat-like wings found in China. Readers will also find out about some of the new technologies used to make these discoveries.


John Bell Hatcher is responsible for finding a number of the most famous dinosaur skeletons out there, with many of his finds housed at Yale, Princeton, The Peabody Museum, and the Carnegie Museum. His discoveries, many made in Wyoming during the 1890s, are only part of what made this man a legend. Dingus explores the life of this “real life Indiana Jones” in this thoroughly engaging biography.


This story traces the history of the fossil site known as Big Bone Lick from the Shawnee legends that tell of a herd of giant bison and a great salt lick to the “discovery” of the fossil site by European settlers in 1739. This discovery captured the imagination of many in what would eventually be known as America, including George Washington and Benjamin Franklin. It opened their eyes to a new way of thinking about the world and gave rise to the study of fossils for scientific purposes. Think of it as paleontology’s (well, American paleontology’s) origin story.




It turns out that Jurassic Park wasn’t Michael Crichton’s only novel to involve dinosaurs. This recently discovered work is set in the American West in 1876 and tells the story of two paleontologists who are ruthless in the pursuit of the most impressive fossil finds. Their rivalry, the “Bone Wars,” serves as the backdrop for a bet between Yale student William Johnson and his arch-rival. He just has to survive the summer in the west. Doing so while working for (first one then the other) the famous paleontologists Cope and Marsh proves to be more difficult than he could have ever imagined.


Mike Wire is a retired homicide detective, now working as the foreman on a Ranch in Montana. When fossils are discovered on the ranch, paleontologist Norman Pickford works out a deal to handle the dig. It soon becomes clear that these fossils are far more important than anyone realized. Someone is even willing to kill over them. Mike realizes that murder can happen anywhere.  The novel is an interesting mix of science and mystery. It builds slowly, but the payoff is worth it.


George R.R. Martin describes The Dinosaur Lords as “a cross between Jurassic Park and Game of Thrones,” and as one of those is his own creation, it’s probably a safe bet to believe him. This series take places in a world not unlike our own 14th century Europe – except for the presence of dinosaurs. They’ve been domesticated, used for beasts of burden, war machines, and any number of things in between. It’s a really interesting concept that will appeal to those who can’t help but wonder what it would have been like to live during the time that the dinosaurs walked the Earth.




This is the perfect  coffee table book for any dinosaur enthusiast. Don’t let the simple cover fool you. Inside you’ll find gorgeous pop-up illustrations, fun facts, and anecdotes about the history of paleontology, like the Bone Wars (mentioned in the Crichton novel above) or the Victorian New Year’s Dinner held inside the belly of a dinosaur skeleton.

Know a kid who is into dinosaurs? Check out this list of 6 Seriously Science-y Dinosaur Books for Future Paleontologists.

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Meet This Tiny Ancestor of the Fearsome T. Rex

Friday, February 22, 2019


Moros intrepidus is a distant relative that lived millions of years before the first T. rex was born, and tells scientists how Tyrannosaurs evolved.

Tyrannosaurus rex has become one of the most notorious predators that ever walked the earth, thanks to in part to movies like Jurassic Park. The T. rex you know and fear was a monster with teeth as long as a person’s forearm. But Tyrannosaurs haven’t always been so gigantic. According to a new fossil discovery, early Tyrannosaurs were much smaller.


Archaeologists working in Utah recently uncovered a fossilized member of a new Tyrannosaur species, called Moros intrepidus. It lived in the area around 100 million years ago, about 15 million years before the first giant Tyrannosaurs appeared.

Uniquely, Moros is significantly smaller than most of the well-known Tyrannosaurs, like the infamous Rex. While T. rex stood nearly 12 feet high, Moros would only come up to an adult human’s waist. It wouldn’t have been much bigger than a large dog.

Interestingly, scientists have found fossils of other Tyrannosaurs that are much older—about 150 million years old, to be exact—that are around the same size as Moros. According to these fossils, the vast majority of Tyrannosaurs were very small, and only started getting big toward the end of their history.

This discovery is a big deal because it fills what has been a blank spot in Tyrannosaurs' history. Prior to the discovery of Moros, we knew about Tyrannosaurs from 150 million years ago, and we knew about Tyrannosaurs from 80 million years ago, but we knew nothing about any of the Tyrannosaurs in between. That was a 70-million-year gap in the fossil record.

"When and how quickly tyrannosaurs went from wallflower to prom king has been vexing paleontologists for a long time,” said lead study author Lindsay Zanno in a press release. “The only way to attack this problem was to get out there and find more data on these rare animals."

Now, thanks to Moros, we have a clearer picture of how Tyrannosaurs evolved. We know that they spent most of their history not as gigantic fearsome predators, but as small and nimble hunters. Arguably, a smaller Tyrannosaur might be even scarier since it can fit through doorways.

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Raptor Noises in ‘Jurassic Park’ Were Made From the Sounds of Tortoises Mating

Saturday, February 23, 2019

Did You Know the Raptor Sounds in 'Jurassic Park' Were Made from Turtle Sex?

If you’re a dinosaur enthusiast, for sure you have already heard  about this secret (that is not so secret!) from Steven Spielberg’s 1993 classic film “Jurassic Park.” The sound effects used for the velociraptors in the movie were not recordings of enraged animals, but actually, two tortoises having sex.

In an interview with Vulture, Gary Rydstrom, the sound designer of the film, said that “If people knew where the sounds in Jurassic Park came from, it’d be rated R!”

Rydstrom was asked to create a bunch of different dinosaur sounds from square one since not even a single living person in this world knows what these humongous creatures would have sounded like. His game plan was to spend months recording animal sounds then modifying the noise to make it sound more real and natural.

So, how did he record these two tortoises mating? The story of how he got the recording is very simple and casual, nothing too funny or upsetting.

“It’s somewhat embarrassing, but when the raptors bark at each other to communicate, it’s a tortoise having sex,” Rydstrom said.

“It’s a mating tortoise! I recorded that at Marine World…the people there said, ‘Would you like to record these two tortoises that are mating?’ It sounded like a joke because tortoises mating can take a long time. You’ve got to have plenty of time to sit around and watch and record them.'”

But tortoises having an “intimate time” together wasn’t the only animal component used to produce raptor noises. Rydstrom also used horse noises, not just for raptors, but also for three to four individual dinosaurs. Hissing sounds that the Raptors made in the film were actually goose noises.

“Birds make pretty raspy sounds, but geese are famous for being the nastiest. You’ve got to get a goose mad and then they hiss at you, and it doesn’t take much to get a goose mad because they seem to get mad at everything,” explained the brilliant sound designer.

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How Sex Killed Tyrannosaurus rex

Sunday, February 10, 2019

AP Photo/Michel Euler

Tyrannosaurus rex, king of the tyrant lizards, may have been the most fearsome land predator to ever exist on planet Earth. Yet despite its lofty position and regal name, T. rex did not live a pampered, kingly lifestyle. True, no other dinosaur species directly predated upon T. rex after it reached the age of two, when an individual would have grown large enough to dissuade any would be attacker, but that doesn't mean that tyrannosaurs cruised through life, succumbing only to death from old age. In reality, life at the top was not a walk in the (Cretaceous) park.

The most obvious source of peril was prey. Tyrannosaurs would try to pick off juvenile, smaller, or sickly dinosaurs, but would still have to reckon with an angry Ankylosaur, Triceratops, or Edmontosaur in the process. A swipe from a clubbed tail could shatter bones, rendering a T. rex unable to hunt and susceptible to starvation. A stab from a horn could result in infection and eventual death. Herbivores may have had to contend with being hunted, but at least they didn't have to do battle every time they wanted a meal.

Infant T. rex suffered the highest mortality, endangered by predators and disease, but upon becoming a juvenile around age two, life was fairly safe, with nearly three-quarters of individuals surviving to their 13th birthday. Here was where things started to get hairy, however

The pre-teens heralded sexual maturity. Combat for mates and nesting sites would turn T. rex against T. rex. Females would also likely experience extreme stress from laying lots of eggs. Between the ages of 13 and 18, mortality for T. rex might have spiked to as high as 23 percent a year. According to Florida State paleontologist Gregory M. Ericksonover half of the known T. rex specimens seem to have died within six years of reaching sexual maturity.

As T. rex battled each other, they might also have been spreading parasites. In 2009, a group of paleontologists theorized that the dinosaurs commonly suffered from Trichomonas gallinae infections, which afflicts modern birds to this day. The parasite eats away at the back of the throat, inflaming nearby tissues and even leaving telltale holes in the back of the lower jaw, which are conspicuously present in many notable T. rex fossils.

Tyrannosaurus rex confirms that life at the top of the food chain is not the easiest, quite the opposite in fact. As few as one in fifty Tyrannosaurs may have reached their maximum attainable body sizes, achieved after living for more than twenty years. Firmly outliving the mighty T. rex were the massive, herbivorous Apatosaurus, Brachiosaurus, and Supersaurus, which could live as long as a century, almost four times longer than the lifespan of Sue, the oldest-known T. rex.


Moros intrepidus: New Deer-Sized Species of Tyrannosaur Discovered

Saturday, February 23, 2019

Moros intrepidus. Image credit: Jorge Gonzalez.

Paleontologists have unveiled a remarkable new species of tyrannosauroid dinosaur from the Cretaceous period: a small relative of Tyrannosaurus rex. The discovery is described in the journal Communications Biology.

Medium-sized, primitive tyrannosaurs have been found in North America dating from the Jurassic period (around 150 million years ago).

By the Cretaceous period (81 million years ago) North American tyrannosaurs had become the enormous, iconic apex predators we know and love.

The fossil record between these time periods has been a blank slate, preventing paleontologists from piecing together the story behind the ascent of tyrannosaurs in North America.

“When and how quickly tyrannosaurs went from wallflower to prom king has been vexing paleontologists for a long time,” said Dr. Lindsay Zanno, a paleontologist at North Carolina State University and head of paleontology at the North Carolina Museum of Sciences.

“The only way to attack this problem was to get out there and find more data on these rare animals.”

The newly-discovered tyrannosaur, named Moros intrepidus, lived about 96 million years ago in the lush, deltaic environment of what is now Utah.

It is the oldest Cretaceous tyrannosaur species yet discovered in North America, narrowing a 70-million-year gap in the fossil record of tyrannosauroid dinosaurs on the continent.

“With a lethal combination of bone-crunching bite forces, stereoscopic vision, rapid growth rates, and colossal size, tyrant dinosaurs reigned uncontested for 15 million years leading up to the end-Cretaceous extinction — but it wasn’t always that way,” Dr. Zanno said.

“Early in their evolution, tyrannosaurs hunted in the shadows of archaic lineages such as allosaurs that were already established at the top of the food chain.”

With a 3.9-foot (1.2 m) length and 78-kg mass, Moros intrepidus ranks among the smallest Cretaceous tyrannosauroids.

Dr. Zanno and colleagues estimate that the individual was over seven years old when it died, and that it was nearly full-grown.

Moros intrepidus was lightweight and exceptionally fast,” Dr. Zanno said.

“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.”

The bones of the new tyrannosaur also revealed the origin of T. rex’s lineage on the North American continent.

When the scientists placed Moros intrepidus within the family tree of tyrannosaurs they discovered that its closest relatives were from Asia.

T. rex and its famous contemporaries such as Triceratops may be among our most beloved cultural icons, but we owe their existence to their intrepid ancestors who migrated here from Asia at least 30 million years prior,” Dr. Zanno said.

Moros intrepidus signals the establishment of the iconic Late Cretaceous ecosystems of North America.”


Lindsay E. Zanno et al. 2019. Diminutive fleet-footed tyrannosauroid narrows the 70-million-year gap in the North American fossil record. Communications Biology 2, article number: 64; doi: 10.1038/s42003-019-0308-7


Dimetrodon Footprints Found on P.E.I. Bring Island to 'World Stage' of Paleontology

Friday, February 22, 2019

Skeleton of D. incisivum, Staatliches Museum für Naturkunde Karlsruhe

'Prince Edward Island holds Canada’s only fossil record of life on land in the Permian period'

A series of footprints found in May in P.E.I. National Park near Cavendish have been confirmed as those of the sail-backed Bathygnathus borealis, more commonly known as Dimetrodon.

Laura MacNeil, who has a background in geology, discovered the footprints while searching for fossils in the area. 

"It was about the size of my hand and it almost looked like a human hand, but if the thumb were replaced with another digit," she said.

"I looked at it for about a half an hour trying to convince myself that this wasn't a fossil because when you're in science, you try to be skeptical because … you don't want to just jump to conclusions."

'The footprints are of creatures that were living'

MacNeil said she ran back to her car to call the the province who then called Parks Canada and Dr. John Calder, a geologist at Saint Mary's University, to confirm what the discovery was. 

"My jaw was open for quite a long time. I couldn't believe it, honestly," she said.

Calder said the footprints belonged to a dimetrodon, a reptile-like mammal that lived 100 million years before the dinosaurs.

"It's the first example from P.E.I. of this type of footprint," he said.

This isn't the first time a dimetrodon fossil has been found on P.E.I.

'The fossil record on P.E.I. is truly world class'

In 1845, the upper jaw bone of a dimetrodon was discovered by a farmer during a well excavation in French River, near the Island's North Shore.

Calder said the discovery of the footprint is especially significant. 

"The bones are of dead creatures, the footprints are of creatures that were living," he said.

"When you see a fossil footprint, it's a living fossil and it shows this animal actually walked here, this is how it stepped, this is where it walked."

Dimetrodons are huge, ancient reptiles related to modern mammals that had giant spiny "sails" on their backs.

They ate giant salamanders in the steamy, swampy forests of the early Permian period, around 290 million years ago. 

Rich prehistoric history

Although fossils are scattered in various places across the Island, these particular footprints are important as they indicate that P.E.I. holds some of Canada's richest evidence of terrestrial fossils of the Permian period.

Their fossils have previously been found in Germany and the United States.

"The fossil record on P.E.I. is truly world class and yet most people don't even know about it," said Calder. ​

MacNeil said the fossil will be studied by scientists and hopefully put on display at P.E.I's national park this summer.