Paleontologists in Brazil have found fossil fragments from a new species of abelisaurid theropod dinosaur that walked the Earth during the Cretaceous period.
The newly-discovered dinosaur lived in what is now southeastern Brazil some 70 million years ago (Late Cretaceous period).
Dubbed Kurupi itaata, the species was a type of abelisaurid, a group of bipedal predators that thrived on the ancient southern supercontinent Gondwana.
Its fossilzied remains were found in the municipality of Monte Alto in western São Paulo state.
“Kurupi itaata represents the first named tetrapod dinosaur for the Marília Formation (Bauru Group), a geological unit that occurs on São Paulo, Minas Gerais, Goiás, and Mato Grosso do Sul states, Brazil,” said Dr. Fabiano Vidoi Iori from the Museu de Paleontologia ‘Pedro Candolo’ and the Museu de Paleontologia ‘Prof. Antônio Celso de Arruda Campos’ and his colleagues.
“This formation consists predominantly of paleosols developed in a semiarid/arid environment and recent reappraisal of its formerly known members reduced its lithological composition and geographical distribution.”
“It has a very sparse vertebrate fossil record without named species so far.”
The paleontologists examined three caudal vertebrae and a partial pelvic girdle of Kurupi itaata.
They found that the ancient beast was approximately 5 m (16.4 feet) long and had a rigid tail.
It was well adapted for running as indicated by its a muscles attachment and bones anatomy.
“This new taxon shares with other South American abelisaurids fused ischia and caudal vertebrae with long and laterodorsally oriented transverse processes, with fan-shaped distal ends,” they said.
“It contributes to the knowledge of the Maastrichtian continental fauna of Brazil and increases the diversity of medium-sized abelisaurids in western Gondwana.”
The discovery of Kurupi itaata is described in a paper in the Journal of South American Earth Sciences.
Fabiano Vidoi Iori et al. New theropod dinosaur from the Late Cretaceous of Brazil improves abelisaurid diversity. Journal of South American Earth Sciences, published online September 4, 2021; doi: 10.1016/j.jsames.2021.103551
Paleontologists have unearthed the fossilized remains of large teratornithid birds at four localities in central Argentina.
Teratorns are members of Teratornithidae, a highly diversified guild of large carnivorous flying birds that lived between 25 million and 12,000 years ago.
Their fossil record is limited exclusively to North and South America. The first teratorn fossils were discovered in 1909 in famous La Brea Tar Pits in California, the United States.
Teratorns are related to living storks and New World vultures such as turkey vultures and condors.
They are among the largest flying birds that ever existed: with a wingspan of up to 7 m (23 feet) and an estimated mass of 70 kg, the teratorn species Argentavis magnificens from the Late Miocene of Argentina is one of the largest flying birds known, only rivaled by the Eocene and Neogene pelagornithids.
“It is believed that teratorns originated in South America because their oldest remains were found in 25- to 5-million-year-old deposits in Brazil and Argentina,” said Dr. Marcos Cenizo, a paleontologist in the Centro de Ciencias Naturales, Ambientales y Antropológicas at the Fundación de Historia Natural Félix de Azara – Universidad Maimónides.
“After this period, teratorns disappeared from the South American fossil record, but became remarkably abundant and diverse in North America until their extinction at the end of the Pleistocene period, some 12,000 years ago.”
“The absence of these gigantic birds during the last 5 million years in South America was a mystery — until now.”
Dr. Cenizo and colleagues examined four new teratorn specimens from localities of central Argentina that range in age from the Late Middle to the Early Late Pleistocene.
“The first specimen that we identified was found in the 1980s at the site of Playa del Barco,” they said.
“We then found two more fossils: one in Centinela del Mar Natural Reserve, close to Mar del Sud and Miramar; and the other in the Salado de Santa Fe river, near Manucho.”
“One more specimen was added, previously reported as a condor, which was collected between 1930 and 1950.”
The new specimens are comparable in size and morphology to a previously known species called Teratornis merriami.
However, they exhibit a set of divergent characters and probably belong to new species.
“The available evidence suggests that forms related to Teratornis lived in the South American Pampas around the time of the Last Interglacial (MIS 5), but they were restricted to North America during the latest Pleistocene (late MIS 3-early MIS 1),” the researchers said.
“The contrasting latest Pleistocene record of teratorns between North and South America is not easy to understand, especially because the supposed flight capacity of these birds did not prevent them from crossing large geographical barriers.”
“Although a bias in the fossil record cannot be ruled out, it is possible that the teratorns were limited in South America by paleoclimatic-paleoecological factors as yet undetermined, and/or that the northern and southern Pleistocene species had very dissimilar specializations.”
The new specimens also shed more light on the paleobiology of teratorn birds.
“The early assumption that teratorns were vulture-like birds with a strict scavenger or raptorial behavior was based on the presence of a sharply hooked beak, their comparable body size and superficial similarity to the condors in limb proportions and morphology, as well as its frequent associated finding with cathartids and other large carnivorous birds,” the authors said.
“However, the relatively weak legs and claws observed in teratorns are not consistent with raptorlike features, and the distinctive morphology of the pectoral and pelvic girdles, skull and jaws appear to be incompatible with vulture-like ecology.”
“Their functional affinities are closer to an opportunistic-piscivorous bird such as the ciconiiforms and pelecaniforms that swallow whole prey.”
M. Cenizo et al. First Pleistocene South American Teratornithidae (Aves): new insights into the late evolutionary history of teratorns. Journal of Vertebrate Paleontology, published online July 9, 2021; doi: 10.1080/02724634.2021.1927064
The word's largest known triceratops skeleton, 'Big John', will be up for auction on 21 October at Paris, where it is expected to fetch up to €1.5m.
The world's largest known triceratops skeleton, 'Big John', will be up for auction on October 21st at Paris’s Drouot auction house where it is expected to fetch up to $1.7 m. Triceratops are known to have roamed the planet some 66 million years ago and, while they were one of the largest creatures from the Cretaceous period, triceratops were plant-eating herbivores that used their large frames and ferocious appearance as defense from predators.
According to the UK's Natural History Museum, a triceratops skull is one of the largest of any land animal in history. Dubbed Big John, this particular specimen lived in Laramidia, an island continent which stretched from present-day Alaska to Mexico. Like any triceratops, it had three horns, a bird-like beak and is believed to have died in an ancient flood plain now known as the Hell Creek geological formation in South Dakota.
The skeleton, which was discovered in May 2014 by geologist Walter W. Stein Bill, went on display in Paris earlier this week. It will go under the auction hammer next month, and unlike the unrealistic dinosaur auctions in the second Jurassic World flick, this one will be very real. Big John has a skull and bony collar that measures 2.62 meters long and 2 meters wide, while its two large horns each measure more than a meter. The skull alone weighs more than 700kg, which is a significant portion of its overall body weight. Fully-formed adults could also measure up to 9 meters in length, although Big John is believed to have only been around the 8-meter mark.
It is worth noting that only about 60% of Big John's skeleton has been recovered, while the skull is about 75% complete. The skeleton was painstakingly put together by joining more than 200 assorted bones to give it its current form. The restoration was carried out in Italy at the Zoic workshop, where specialists restored the prehistoric skeleton. Researchers have also found a laceration on Big John's collar, which suggests it was seriously injured during its lifetime, possibly in a fight with another triceratops during a dispute over territory or a mate.
Dinosaur skeletons are hot property in the global auction scene, thanks in part to movies like Jurassic Park and Jurassic World. Last year, the skeleton of an Allosaurus, one of the oldest dinosaurs and a predecessor of the T-Rex, was snapped up by an anonymous buyer for more than €3m, almost twice the estimate. However, that's a pittance compared to the record $31.8 million that was paid last October for the skeleton of a T-Rex named Stan that researchers expected to fetch only between $6-$8 million. It will be interesting to see how much Big John goes for, but going by recent trends, it won't be a major surprise if it is significantly higher than the projected price.
First described in 1840, the genus is related to modern-day chimaeras and currently includes over 10 scientifically recognized species.
The newly-discovered teeth belong to Petalodus ohioenesis, a previously known member of the genus that lived some 290 million years ago (Permian period).
“The specimens are characterized by petal-shaped teeth with a spade-like crown, and a long, tongue-shaped root,” said Dr. Zhikun Gai, a paleontologist in the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, the CAS Center for Excellence in Life and Paleoenvironment, and the University of Chinese Academy of Sciences, and his colleagues.
“The crown is circled with a band or cingulum composed of imbricated ridges at the base.”
“All seven teeth are assigned to Petalodus ohioenesis because of their vertically narrow cingulum and much longer root.”
The well-preserved teeth of Petalodus ohioenesis were collected from the Qianshi limestone layer of the middle-upper Taiyuan Formation in Yangquan city, north China.
This is not only the first fossil record of Petalodus in China, but also only the second record in Asia.
“During the Carboniferous and Permian periods, the fossil site of Yangquan was part of the North China Craton at paleoequatorial areas of the Paleo-Tethys Ocean and experienced a wet tropical climate,” the paleontologists said.
“A great diversity of invertebrate fossils, including crinoids, bryozoans, brachiopods, gastropods, cephalopods, corals, fusulinids, ostracods, and trilobites, have been reported associated with the teeth of Petalodus ohioensis in this region, which would have provided an abundant food source for the diet of this species.”
The study was published in the journal Acta Geologica Sinica.
Zhikun Gai et al. First Record of Petalodus Owen, 1840 (Chondrichthyes, Petalodontidae) in the Lower Permian (Cisuralian) of China. Acta Geologica Sinica, published online June 21, 2021; doi: 10.1111/1755-6724.14784
Yeyuna's Jurassic Architect is now available on Steam and allows players to build their own high-tech colony in the dangerous age of dinosaurs.
Polish indie developer Yeyuna has just released Jurassic Architect, a Steam title that allows players to build their own Jurassic World-style dinosaur park. Dinosaurs and video games typically go together pretty well, especially ones that allow players to interact with the great beasts of the past - or at least try to avoid becoming a T-Rex’s latest meal.
The most recent dinosaur game of note is the upcoming Jurassic World: Evolution 2, the sequel to 2018’s licensed construction and management simulator that was announced by Jeff Goldblum himself at June’s Summer Games Fest Kickoff Live event. Set to arrive sometime later this year, Jurassic World: Evolution 2 promises to expand upon the dinosaur-raising gameplay of the original while adding new species and features like helicopter riding and dinosaur hunting. In the meantime, players will be able to scratch their dino-wrangling itch with an unrelated but interesting indie title that just launched on Steam.
In a recent press release, Yeyuna announced that its newest indie title, Jurassic Architect, is now available on Steam, as well as posting a new Jurassic Architect trailer to YouTube. Set in a not-too-distant future where the Earth’s resources are all but depleted, Jurassic Architect tasks players with building a new human civilization in prehistoric times. Since dinosaurs still roam the Earth at this uncharted time, players will need to manage a crew of scientists, soldiers, and farmers as they work to maintain their new home and tame the wild prehistoric beasts that roam it. While some dinosaurs are dangerous, others can be used to mine resources or serve as a mode of transport against the wild, untamed terrain.
Yeyuna CEO Sebastian Żaczek cited his love of city-building games like SimCity and Cities Skylines as an inspiration for Jurassic Architect, and he hopes to blend the mainstay conventions of the genre with a fun dinosaur theme. In addition to building new settlements and managing wildlife, players will also be able to set up entertainment for their colonists, with the trailer above showing what appears to be a dinosaur combat arena of some kind. Jurassic Architect also includes some tower defense elements, as players are shown defending their bases from hungry carnivores using some kind of remote-controlled turrets.
While Jurassic Architect isn’t connected to the Jurassic World franchise in any way aside from the first part of its name, Yeyuna's time-traveling city building simulator seems to follow in Jurassic World: Evolution's spirit of humans surviving in a world of dinosaurs and even taming them for their own uses. Interested players can try Jurassic Architect out for themselves on Steam to see if they have what it takes to set up a new human civilization in the age of dinosaurs.
Everyone has heard of dinosaurs, and for most, the creatures are as fascinating as they are terrifying. But while scientists continue to uncover truths about these ancient creatures, what we know about their lives and behavior changes how we perceive them.
With movies marketing fictitious imagery about dinosaurs, it’s important to consider what fossils and real scientists say. Dinosaurs are not the gigantic scaley green ‘chompers’ that movie classics like “Jurassic Park” brought back to life. Factual dinosaur tell-alls show that most dinosaurs had feathers like birds while others reproduced as teens to avoid going extinct.
Here are the top 10 surprising dinosaur facts.
10 - Dinosaurs Grew Fast
In nature, there is no one-size-fits-all mentality to understand growth. It varies from one species to another. For bigger dinosaurs to achieve their size, they underwent massive growth spurts since they didn’t live too long as adults. It was the trick to their survival: grow fast.
The Titanosaurs are considered the largest reptiles and probably the largest animals to ever walk the Earth. Titanosaurs were four-legged herbivores and weighed at least 90 tons — that’s about 25 grown elephants. The Titanosaurs’ size resulted in some big babies. They hatched with almost adult-like proportions.
Another dinosaur that grew fast was the Mamenchisaurus, an herbivore with a 35-foot long neck as an adult. This bizarrely giant reptile took 30 years to grow to about 70 feet. But these insane growth spurts didn’t affect the biggest dinosaurs alone. Unlike other species that grew slowly over time, the tyrannosaurus rex also underwent huge growth in its teenage years.
9 - Dinosaurs Never Went Extinct
Dinosaur enthusiasts will always tell you that while dinosaur fossils are valuable, we can always see them if we look at the creatures in our skies. Research shows that dinosaurs live and breathe all around us, but we prefer to call them birds.
In the 1960s, paleontologists discovered the Deinonychus, a carnivorous dinosaur that roamed North America during the early Cretaceous period. A study of the species revealed that they share some stark similarities to birds. They were bipedal, which means they walked on two legs, and their main weapon was their sickle-like talons that grew to about five inches long! To maintain balance as they ran to attack prey, Deinonychus used their tail.
Fossils of the Deinonychus show that the bodies of the bird ancestors shrank over time as they adapted to changes in their environment. While it would be arrogant to imagine a Tyrannosaurus rex shrinking into a bird, it is important to appreciate that the process was millions of years in the making. So, the next time you see a pigeon or chicken, just imagine that they were once tough reptiles that ruled the world.
8 - Some Dinosaurs Were Smarter Than Others
Researchers agree that the Stegosaurus was the dumbest dinosaur – aw, poor dumb dino — while the Trodoon was the most intelligent.
The Stegosaurus was a four-legged herbivore, well-known for the upright plates on its back and spiked tail. While the Stegosaurus was gigantic at about nine meters long, studies reveal that they had a brain the size of a walnut. The brain size is inadequate for such a giant reptile, making the plates on its back logical. They needed extra protection from predatory dinosaurs since they might have had trouble “thinking outside the box.”
The Trodoon had fewer things to worry about since it was smaller with a large brain to boot. The predatory reptile had stereo vision, speed, and big eyes to spot its prey, making it a threat to smaller reptiles.
Other smart dinos include the chicken-sized compsognathus and the Deinonychus. According to “Jurassic Park,” the Deinonychus could open a doorknob. While the movie’s exaggerations hyped up the magnificent reptile, research suggests they could strategize and communicate. If you ever go back in time, pray you don’t cross paths with this smart bunch!
7 - Dinosaurs Lived On All Continents
When dinosaurs roamed the Earth, they roamed all of it. During the Triassic period, about 230 million years ago, the Earth was made up of a single continent called Pangea. Gradually, as the supercontinent broke up into smaller continents, dinosaurs found themselves moving with the newly created continents.
Over the years, evidence that dinosaurs lived all over the world has been found on all continents. From Europe to the Americas, Africa, and Asia, fossils of the beasts have been uncovered from the dirt.
6 - An Asteroid Didn’t Kill Off All The Dinosaurs
The most popular misconception about the extinction of the dinosaurs was that an asteroid landed in the Yucatan Peninsula and eradicated them in one fell swoop! As dramatic as that sounds, this one single extinction-level event was not responsible for the disappearance of all dinosaurs.
The Earth also helped kill off the dinosaurs, one species after another, over a long time. The truth is that about 66 million years ago, an asteroid entered the Earth’s atmosphere and, after landing, created true chaos. The impact of the 7.5 miles asteroid vaporized soot, started wildfires, and with soot covering the entire planet, animals stood no chance. Things were so terrible that carbonated soot engulfed the globe blocking the Sun from reaching the Earth. It was a dark event, literally.
The post-apocalyptic conditions after the asteroid have been responsible for the extinction of 76% of the Earth’s species. Plants and animals, including the dinosaurs, were part of this unfortunate group. The event is a great lesson to humanity and why we need to look for stellar beings heading our way!
5 - Dinosaurs Were As Big As Buildings Or Small As A Chicken
Most of us picture the big and dangerous types of dinosaurs, but they were not the only ones. Dinosaur sizes range from ones as big as buildings to others that were so small you could confuse them for chickens!
The Titanosaur is generally accepted as the largest dinosaur standing on the ground at about 46 feet, allowing them to eat leaves as high as a five-story building. This evolutionary advantage is almost unbelievable. If the Titanosaur is to be exhibited, a museum might have to take the roof off to accommodate it. Others like the Sauroposeidon were equally intimidating at almost 42 feet.
On the smaller side, the Lesothosaurus is considered one of the smaller species, approximated to be the size of a chicken. For a plant-eater, the reptile was a perfect size, but it was not the smallest. Paleontologists discovered that the Oculudentavis khaungraae was even smaller, the size of a hummingbird. In the dinosaur world, size was an issue.
4 - Most Dinosaurs Were Vegetarian
Books and movies are all the rage with the Tyrannosaurus rex and velociraptors that suggest dinosaurs were always looking to attack prey. Yet, research suggests that dinosaurs might have been more peaceful than we have been led to believe. Most of them were vegetarian, which means they wouldn’t have attacked without provocation.
In the natural world, there is balance, and often enough, carnivores are small in number compared to herbivores. In the age of the dinosaurs, this rule was also true as Hadrosaurs, Ornithopods, and Sauropods roamed the planes in search of vegetation. These reptiles were more concerned with feeding and, while traveling in herds, protected themselves from scores of predators. Theropods, the flesh-eating dinosaurs, hunted the vegetarian dinosaurs as their meals, creating a balance in nature.
So, while movies use Tyrannosaurus-rex and Velociraptors as the selling image for dinosaurs, they ignore the fact that they were largely peaceful.
3 - Cold-Blood Protected Dinosaurs
Reptiles are largely cold-blooded as they rely on the environment around them to heat themselves internally. Research reveals that as reptiles, dinosaurs might have been neither cold-blooded nor warm-blooded. If they were fully warm-blooded, they could have microwaved themselves from the inside out because of their humongous sizes.
Paleontologists studying the physiology of dinosaurs found that while the reptiles were believed to be cold-blooded, their growth and active lifestyles suggest otherwise. The high growth rates of dinosaurs suggest that they might have been ‘mesotherms,’ which means part cold-and-warm blooded.
The designation as mesotherms justifies the growth of the large reptiles and the hunger-driven personalities of the predators. Dinasaurs needed the energy to fuel their bodies.
2 - Dinosaurs Most Likely Had Feathers, Not Scales
You’ve probably heard that dinosaurs share many similarities with birds, and this extends to feathers. While birds are long believed to be the only creatures with feathers, it seems dinosaurs had them first. The surprising thing is that even dinosaurs that were not direct relatives to birds have been found with feathers.
In 1996, scientists unearthed the Sinosauropteryx, a theropod that had feathers. The discovery helped along in proving theories on the look and behavior of dinosaurs millions of years ago. Dinosaurs were not the green and scaly creatures we see on tv, as all evidence shows they were feathered beasts.
While the verdict is still out on whether all dinosaurs were feathered, scientists are convinced that many meat-eaters were feathered. These are the direct relatives of birds that are descendants of avian variants. If you love chicken, maybe you could have domesticated a pet Tyrannosaurus rex if you got over the “It might eat me” phase.
1 - Powerful T. Rex Teeth!
This list features some incredible facts about dinosaurs, and the top spot belongs to none other than the majestic Tyrannosaurus rex. The Tyrannosaurus rex gets a bad rap for its ridiculously short arms, but the carnivore had saw-like teeth that made it an apex predator.
Studies have shown that the 45-feet long beast had 10-inch long teeth that sustained a hyper-carnivorous feeding style. With a special arrangement of dentine that strengthened its teeth, the t-rex could crush bones and take at least 500 pounds in a single bite. Five hundred pounds is about the size of a fully grown Siberian tiger, which shows just how powerful the Tyrannosaurus rex was.
Skeletal data reveals that to accommodate about 60 teeth, the Tyrannosaurus rex had a 4-foot-long jaw. So, while movies glorify the Tyrannosaurus rex, it’s easy to see that it deserves the praise and fear for its power to shred prey.
An incomplete fossil record hampers reconstructing the early evolution of caimans (subfamily Caimaninae). In new research, paleontologists from Germany and the United States have described two previously unpublished, 52-million-year-old fossils of a key caiman species, Tsoabichi greenriverensis, from the early Eocene Green River Formation in Wyoming.
Caimans are small to large crocodilians belonging to the subfamily Caimaninae, one of two primary lineages within Alligatoridae, the other being alligators.
These animals can be found in marshes, swamps, mangrove rivers and lakes of Mexico, Central and northern South America.
They are relatively small-sized crocodilians with an average length of 1.5 to 2.5 m (5-8.2 feet) and weight of 6 to 40 kg, with the exception of the black caiman (Melanosuchus niger), which can grow more than 4 m (13.1 feet) in length.
Caimans are distinguished from alligators, their closest relatives, by a few defining features: a lack of a bony septum between the nostrils, ventral armor composed of overlapping bony scutes formed from two parts united by a suture and relatively longer, more slender teeth than those possessed by alligators.
“In the study, we investigated the question of whether the caimans originally came from North or Central America,” said University of Tübingen’s Dr. Márton Rabi and colleagues.
“Using other caiman fossils from Central America, we determined that these species actually represent extinct species more closely related to caimans living today. However, the caimans originally evolved in North America,” added Dr. Jules Walter, also from the University of Tübingen.
“Caimans probably spread from there to South America in the Cretaceous period about 66 million years ago, around the time of the mass extinction of the dinosaurs.”
“Of all the dinosaur species, only the ancestors of today’s birds survived. However, freshwater species such as crocodiles were not as strongly affected by the great extinction.”
“In the Cretaceous, North and South America were connected only by a chain of islands, so caimans had some difficulties to overcome.”
“Nevertheless, it wasn’t the only dispersal between North to South America during evolution; there must have been further migrations between the two continents.”
The team’s analysis suggests that either a species of caiman developed in South America migrated back to North America, giving rise to Tsoabichi greenriverensis and others; or that there was a later, second wave of migration from North to South America.
“The caiman species living today would then have evolved from this group,” Dr. Rabi said.
“In the more recent geological past, caimans again advanced from the south into Central America, this time the living species.”
“However, since there were no longer any suitable corridors with wetlands to the north during this period, they did not reach North America.”
“The evolutionary history of caimans underscores that the ability to migrate and spread is crucial,”
“A species’ ability to do this — or to diverge into new species — is often the only way it can survive when the environment changes.”
“Today, the destruction of many habitats by humans is leading to isolated populations.”
“Species often cannot spread further even if, for example, a changing climate puts pressure on them to do so.”
The study was published in the journal Historical Biology.
Jules Walter et al. On the origin of Caimaninae: insights from new fossils of Tsoabichi greenriverensis and a review of the evidence. Historical Biology, published online August 19, 2021; doi: 10.1080/08912963.2021.1938563
“If Ectenosaurus clidastoides with its long, slender jaws resembles a gharial crocodile, the new species is closer to a false gharial crocodile with notably blunter jaws,” said Dr. Takuya Konishi, a paleontologist in the Department of Biological Sciences at the University of Cincinnati.
The fossilized jaw of Ectenosaurus everhartorum was collected in the 1970s in Logan County, western Kansas.
“Mosasaurs in western Kansas have been well sampled and well researched,” Dr. Konishi said.
“Those two factors create tall odds when you try to find something new.”
Ectenosaurus mosasaurs are unusual for how few specimens have been found in the genus compared to other mosasaurs.
“In western Kansas we have over 1,500 mosasaur specimens,” Dr. Konishi said.
“Out of those we can only find one specimen each representing these two species of Ectenosaurus. That’s sort of crazy.”
The discovery is reported in a paper in the Canadian Journal of Earth Sciences.
Alexander J. Willman et al. A new species of Ectenosaurus (Mosasauridae: Plioplatecarpinae) from western Kansas, USA, reveals a novel suite of osteological characters for the genus. Canadian Journal of Earth Sciences, published online August 26, 2021; doi: 10.1139/cjes-2020-0175
Chase Doran Brownstein from the Department of Ecology and Evolutionary Biology at Yale University and the Stamford Museum and Nature Center has described two new dinosaurs — a herbivorous hadrosaur and a carnivorous tyrannosaur — that lived in the North American paleolandmass Appalachia during the Late Cretaceous Period, some 85 million years ago.
For most of the second half of the Cretaceous period, North America was divided into two land masses, Laramidia in the West and Appalachia in the East, with the Western Interior Seaway separating them.
“One reason is that Laramidia’s geographic conditions were more conducive to the formation of sediment-rich fossil beds than Appalachia’s,” said Brownstein, author of a paper published in the journal Royal Society Open Science.
The specimens he examined were collected in the 1970s from the Late Cretaceous Merchantville Formation in New Jersey and Delaware.
“These specimens illuminate certain mysteries in the fossil record of eastern North America and help us better understand how geographic isolation affected the evolution of dinosaurs,” Brownstein said.
The paleontologist examined a partial skeleton of a large predatory therapod, concluding that it is probably a tyrannosaur.
He noted that the fossil shares several features in its hind limbs with Dryptosaurus, a tyrannosaur that lived about 67 million years ago in what is now New Jersey.
The dinosaur had different hands and feet than Tyrannosaurus rex, including massive claws on its forelimbs, suggesting that it represents a distinct family of the predators that evolved solely in Appalachia.
“Many people believe that all tyrannosaurs must have evolved a specific set of features to become apex predators,” Brownstein said.
“Our fossil suggests they evolved into giant predators in a variety of ways as it lacks key foot or hand features that one would associate with western North American or Asian tyrannosaurs.”
“The partial skeleton of the hadrosaur provided important new information on the evolution of the shoulder girdle in that group of dinosaurs,” he added.
“The hadrosaur fossils also provide one of the best records of this group from east of the Mississippi and include some of the only infant/perinate dinosaur fossils found in this region.”
Chase Doran Brownstein. 2021. Dinosaurs from the Santonian-Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America. R. Soc. open sci 8 (8): 210127; doi: 10.1098/rsos.210127
A nearly complete skeleton of a tapejarid pterosaur that lived during the Cretaceous Period was intercepted during a police raid at Santos Harbour in the Brazilian state of São Paulo and confiscated together with several other exceptionally well-preserved fossils.
“The pterosaur clade Tapejaridae was a major component of Early Cretaceous continental faunas, achieving a widespread distribution in Gondwana and Eurasia,” said Dr. Victor Beccari from the Universidade de São Paulo and the Universidade Nova de Lisboa and his colleagues.
“Tapejarids are characterized by their edentulous jaws and often huge cranial crests, and are sometimes inferred to have had an herbivorous diet.”
“In Brazil, tapejarids are among the most abundant and diverse pterosaur taxa, recovered from the Crato and Romualdo Lagerstätten (Araripe Basin, northeastern part of the country) and from the desertic environments of the Goiô-Erê Formation (Paraná Basin, southern Brazil).”
The newly-described specimen was recovered from the Early Cretaceous Crato Formation of Brazil.
It includes nearly the entire body, mostly intact and even including remnants of soft tissue alongside the bones.
According to the team, it is indeed the best-preserved tapejarid skeleton known so far, shedding new light on the anatomy of this pterodactyloid clade.
“This is the first time that we have been able to study more than just the skull of this species,” the paleontologists said.
The analysis suggests Tupandactylus navigans had a terrestrial foraging lifestyle, due to its long neck and the proportions of its limbs, as well as its large head crest that could negatively influence long-distance flight.
However, the specimen possesses all the necessary adaptation for powered flight, such as the presence of a notarium and a developed muscle anchoring region in the arm bones.
The specimen also has an unusually large crest on its chin, part of its already impressive skull ornamentation.
“We described the most complete tapejarid fossil from Brazil, a partially articulated skeleton of Tupandactylus navigans with soft tissue preservation,” the researchers said.
“This specimen brings new insights into the anatomy of this animal and its constraints for flight, arguing for terrestrial foraging ecology.”
The findings were published in the journal PLoS ONE.
V. Beccari et al. 2021. Osteology of an exceptionally well-preserved tapejarid skeleton from Brazil: Revealing the anatomy of a curious pterodactyloid clade. PLoS ONE 16 (8): e0254789; doi: 10.1371/journal.pone.0254789