nandi's blog

Several Species of Pseudo-Horses Lived in Spain 37 Million Years Ago

Thursday, July 8, 2021

Palaeotheriid mammal Leptolophus cuestai (left) and equoid perissodactyl Pachynolophus zambranen (center and right). Image credit: Ulises Martínez Cabrera.

Paleontologists have identified two new species of palaeotheriid mammals from fossils found at the Eocene site of Zambrana in Alava, Spain.

The two new species, named Leptolophus cuestai and Leptolophus franzeni, lived 37 million years ago in what is now Spain.

They belong to Palaeotheriidae (pseudo-horses), an extinct family of herbivorous that ranged across Europe and Asia from the Eocene through to the early Oligocene.

“Can one imagine animals similar to horses with three toes, the size of a fox terrier, a Great Dane and a donkey living in a subtropical landscape in Alava? Many of these pseudo-horses have been described at the Zambrana site,” said Dr. Ainara Badiola, a researcher at the Universidad del País Vasco/Euskal Herriko Unibertsitatea.

“Examples of them are Pachynolophus zambranensis and Iberolophus arabensis, which were first specified in this paleontological enclave.”

Leptolophus cuestai and Leptolophus franzeni not only expand the fossil record and the biodiversity of palaeotheriid fauna, but also display dental features atypical for Eocene horses.

“Their molars have a very high crown and are covered with a thick layer of cementum,” said Dr. Leire Perales-Gogenola, also from the Universidad del País Vasco/Euskal Herriko Unibertsitatea.

“This type of dentition, also present in other endemic Iberian palaeotheriids, could be indicative of a difference in environmental conditions between the Iberian and Central European areas, with more arid conditions or less dense or closed forests and the presence of more open areas in Iberia.”

Leptolophus cuestai also had molars with atypically high crowns, similar to those of some of the earliest horses in Europe.

“At the end of the Eocene in Europe, forests of an intertropical type gradually disappeared, giving way to plant communities of a more temperate type with more open areas,” the paleontologists said.

“Modern horses appeared in Europe later on during the Miocene (23-5.3 million years ago).”

“Their dentition, with very high crowns, was adapted for eating vegetation with high grit content (grasses).”

The findings were published in the Journal of Vertebrate Paleontology.


Leire Perales-Gogenola et al. New Leptolophus (Palaeotheriidae) species from the Iberian Peninsula and early evidence of hypsodonty in an Eocene perissodactyl. Journal of Vertebrate Paleontology, published online May 20, 2021; doi: 10.1080/02724634.2021.1912061


Iconic Independence Day Line Is a Nod to Jurassic Park

Monday, July 5, 2021

Independence Day writer Dean Devlin states that Jeff Goldblum's "must go faster" line is a reference to another of the actor's films: Jurassic Park.

According to Independence Day writer Dean Devlin and star Jeff Goldblum, one of the movie's iconic lines came from another of the actor's films: Jurassic Park.

The production of Independence Day offered some leeway in terms of improvisation, which led to some of the film's most famous lines. In an interview with The Hollywood Reporter, Devlin mentioned how he would sometimes ask the cast to say certain things. "Whenever they would improv, I would sometimes come in and suggest a word to throw in," Devlin said. "So I just ran in and said, 'We'll probably cut it later, but you [Goldblum] got to give me the 'must go faster' line from Jurassic Park.'"

Goldblum was a little more apprehensive about the usage of the line in the film. "I was loath to appropriate from some other character [Goldblum's Dr. Ian Malcolm], and I hoped Mr. Spielberg wouldn't be unhappy that we'd used it. I think it all worked out." The line ended up staying in the movie, taking place near the end of the film as Goldblum and Will Smith's characters are flying out of the alien spaceship after planting the explosives that would save the day. The scene also saw another famous improvised Goldblum line, "The fat lady. You're obsessed with the fat lady," stated shortly before saying "Must go faster."

In Jurassic Park, the line occurs in a similarly tense escape moment, as Goldblum's character and others are attempting to outrun the movie's infamous T. Rex. The Jurassic Park line itself was improvised by the movie's director, Steven Spielberg, during the filming of the scene. When it came to Independence Day, Goldblum said improvisation was for the sake of entertainment. "We improvised, we were fooling around, having a good time."

The cast and crew mentioned several other famous improvised lines and scenes, such as Smith's attempt attempt at steering the UFO. Director Ronald Emmerich created a sticker for the scene that led to Smith reversing the ship before Goldblum turns the sticker around, suggesting "You go that way."

David Brenner, the film's editor, had no issue with keeping the improvised lines. "I just felt free to put in stuff I thought was fun and cool," he said. "Even if it sometimes was going to make a scene longer, you want to get this stuff in because you are not sure at the end how much comedy plays." Ultimately, some of the movie's most iconic lines were the product of improvisation, and according to the Independence Day crew, were for the sake of having fun.

Source: The Hollywood Reporter /

Study: Climate Change Drove Prehistoric Proboscideans to Extinction

Saturday, July 3, 2021

Dusk falls on East Africa’s Turkana Basin 4 million years ago, where our early upright-walking ape ancestors, Australopithecus anamensis (foreground), shared their habitat with several co-existing proboscidean species, as part of a spectacular herbivore community containing some progenitors of today’s charismatic East African animals. Background (left to right): Anancus ultimus, last of the African mastodonts; Deinotherium bozasi, colossal herbivore as tall as a giraffe; Loxodonta adaurora, gigantic extinct cousin of modern African elephants, alongside the closely-related, smaller Loxodonta exoptata. Middle ground (left to right): Eurygnathohippus turkanense, zebra-sized three-hoofed horse; Tragelaphus kyaloae, a forerunner of the nyala and kudu antelopes; Diceros praecox, an ancestor of the modern black rhino. Image credit: Julius Csotonyi.

new study, published in the journal Nature Ecology & Evolution, challenges claims that early humans slaughtered mammoths, mastodonts and prehistoric elephants to extinction over millennia.

“The worldwide extirpation of megafaunas was a radical upheaval in the recent evolutionary history of terrestrial ecosystems, with Late Pleistocene human activities often considered culpable,” said lead author Dr. Juan Cantalapiedra from the University of Alcalá and his colleagues.

“Yet, understanding these extinctions in view of long-term macroevolutionary dynamics of the megafauna lineages has been critically lacking.”

“Proboscideans, being keystone megaherbivores in Cenozoic terrestrial ecosystems, were among the most affected groups,” they noted.

“For centuries, their fossil record elucidated an evolutionary history of success and decline in equally dramatic measures, with three endangered living elephant species representing a mere vestige of a once formidable clade high in both taxonomic diversity and ecomorphological disparity, which spread across Africa, Eurasia and the Americas.”

“Therefore, proboscidean evolution poses an invaluable case study for palaeobiologists to explore causes of uneven distribution in biodiversity across phylogeny and evolutionary history.”

In the study, the researchers re-examined the rich fossil record of proboscideans in its entirety and investigated the interactions between their diversification and the timing of their evolution.

They compiled a dataset for extinct and living proboscideans with unprecedented detail, which consists of 185 species, 2,130 fossil occurrences, and 17 traits (such as body size, skull shape and the chewing surface of their teeth).

By investigating these traits, they discovered that all proboscideans fell within one of eight sets of adaptive strategies.

“Remarkably for 30 million years, the entire first half of proboscidean evolution, only two of the eight groups evolved,” said co-author Dr. Zhang Hanwen, a researcher in the School of Earth Sciences at the University of Bristol.

“Most proboscideans over this time were nondescript herbivores ranging from the size of a pug to that of a boar.”

“A few species got as big as a hippo, yet these lineages were evolutionary dead-ends. They all bore little resemblance to elephants.”

“The course of proboscidean evolution changed dramatically some 20 million years ago, as the Afro-Arabian plate collided into the Eurasian continent.”

“Arabia provided crucial migration corridor for the diversifying mastodont-grade species to explore new habitats in Eurasia, and then into North America via the Bering Land Bridge.”

“The immediate impact of proboscidean dispersals beyond Africa was quantified for the very first time in our study,” Dr. Cantalapiedra said.

“Those archaic North African species were slow-evolving with little diversification, yet we calculated that once out of Africa proboscideans evolved

“One case in point being the massive, flattened lower tusks of the shovel-tuskers. Such co-existence of giant herbivores was unlike anything in today’s ecosystems.”

By 3 million years ago the elephants and stegodonts of Africa and eastern Asia seemingly emerged victorious in this unremitting evolutionary ratchet.

However, environmental disruption connected to the coming Ice Ages hit them hard, with surviving species forced to adapt to the new, more austere habitats.

The most extreme example was the woolly mammoth, with thick, shaggy hair and big tusks for retrieving vegetation covered under thick snow.

The scientists identified final proboscidean extinction peaks starting at around 2.4 million years ago, 160,000 and 75,000 years ago for Africa, Eurasia and the Americas, respectively.

“It is important to note that these ages do not demarcate the precise timing of extinctions, but rather indicate the points in time at which proboscideans on the respective continents became subject to higher extinction risk,” Dr. Cantalapiedra said.

Unexpectedly, the results do not correlate with the expansion of early humans and their enhanced capabilities to hunt down megaherbivores.

“We didn’t foresee this result. It appears as if the broad global pattern of proboscidean extinctions in recent geological history could be reproduced without accounting for impacts of early human diasporas,” Dr. Zhang said.

“Conservatively, our data refutes some recent claims regarding the role of archaic humans in wiping out prehistoric elephants, ever since big game hunting became a crucial part of our ancestors’ subsistence strategy around 1.5 million years ago.”

“Although this isn’t to say we conclusively disproved any human involvement. In our scenario, modern humans settled on each landmass after proboscidean extinction risk had already escalated. An ingenious, highly adaptable social predator like our species could be the perfect black swan occurrence to deliver the coup de grace.”


J.L. Cantalapiedra et al. The rise and fall of proboscidean ecological diversity. Nat Ecol Evol, published online July 1, 2021; doi: 10.1038/s41559-021-01498-w



Saturday, July 3, 2021

The movie that changed the movie industry! That's how many refer to Jurassic Park, a franchise that has become a classic since the first movie. Released in 1993, Jurassic Park was a real success and became the most sought-after movie in blockbusters. The film depicts a park built by a millionaire (Richard Attenborough) with several extinct dinosaurs sixty-five million years ago. The film is not just a fantasy story, but a science fiction story, like dinosaurs, come to life thanks to a fossilized insect and its DNA.

Directed by Steven Spielberg, the film became a generation favorite and set the course for visual effects in cinema. With an estimated box office of 1.29 billion dollars, the feature is considered one of the most influential films of all time. Today, almost 30 years after their release, the films still make fans worldwide, earning tributes, clothing lines, shoes, hotels, and even slot games in casinos, as shown by while reviewing Netbet.

The movie that changed the movie industry

And why is Jurassic Park so attractive? What made it a success, and why do many say he changed the way he made movies? The film marked cinema thanks to the techniques used to carry out special effects. Through animatronic robots, Spielberg was able to bring the dinosaurs to life, which made the whole visual experience very realistic, especially by the standards of the time. The film’s visual effects are so impressive that even today, it is at the highest standards.

And of course, all this work had effects not only on the box office but also on the awards. The film received three Oscar awards in Best Visual Effects, Best Sound, and Best Sound Editing. Its impact originated five other films in the franchise and became a success story for companies around the world.

Fun Facts You Maybe You Didn't Know About Jurassic Park.

In this post, we list five curiosities about the film that helped Jurassic Park become one of the films that changed cinema history. Check out our selection below and discover some little-known information from this science fiction lab-created dinosaur.

  1. Steven Spielberg changed the film's climax weeks before the shooting ended. He felt that the audience would hate him if the T-rex didn't have a heroic appearance, as the filmmaker believed that the dinosaur was the star of the movie. So, he decided to create the fight between the Velociraptors and the T-rex, a sequence that was done entirely in computer animation, unlike the other T-rex attacks. The original scene would show the Velociraptors killed by the Tyrannosaurus skeleton seen in the Visitors Center.
  1. With more than two hours in length, Jurassic Park has only 15 minutes of footage with “real” dinosaurs, nine minutes from animatronics, and six minutes through CGI (Computer Graphics).
  1. Before deciding to use animatronic animals and CG images for dinosaur-related effects, Spielberg wanted to use stop-motion animation for these effects.
  1. Although the book that originated the film was only published in 1990, pre-production on Jurassic Park began in 1989 using only author Michael Crichton's manuscript.
  1. Associated with the book, the film generated so much interest in dinosaurs that it recorded a record increase in students interested in the study of paleontology.

What to expect from the new Jurassic Park movie

Jurassic Park has three films from the first sequel, Jurassic Park, The Lost World, and Jurassic Park 3. And three other films from the new sequel, Jurassic WorldFallen Kingdom, and the subsequent release scheduled for 2022 Jurassic World: Dominion.

The first teaser of the new movie was released on June 11th, and despite having only 15 seconds, it is possible to see how the dinosaurs will be even more accurate. Colin Trevorrow, the film's director, explained to Entertainment Weekly that Jurassic World: Dominion will tell more about the dinosaurs' past and how they emerged in the Cretaceous period.


Jurassic Park has not become a movie classic just for the visual effects and for the plot and the way Steven Spielberg brought them to life. Many viewers worldwide and fans of the franchise claim that the film was an experience for those who watched, taking everyone into the long-forgotten universe of dinosaurs.


Paleontologists Find New Beetle Species in Coprolite of Triassic Dinosaur Relative

Friday, July 2, 2021

Contents of a coprolite fragment from the Krasiejów locality in Poland. Image credit: Qvarnström et al., doi: 10.1016/j.cub.2021.05.015.

By scanning a fossilized coprolite of Silesaurus opolensis, a dinosaur relative that lived 230 million years ago (Triassic period) in what is now Poland, paleontologists discovered a previously unknown species of ancient beetle.

“We didn’t know how insects looked in the Triassic period and now we have the chance,” said Dr. Martin Fikáček, an entomologist at National Sun Yat-sen University.

“Maybe, when many more coprolites are analyzed, we will find that some groups of reptiles produced coprolites that are not really useful, while others have coprolites full of nicely preserved insects that we can study.”

“We simply need to start looking inside coprolites to get at least some idea.”

“I was really amazed to see how well preserved the beetles were, when you modeled them up on the screen, it was like they were looking right at you,” added Dr. Martin Qvarnström, a paleontologist at Uppsala University.

“This is facilitated by coprolites’ calcium phosphatic composition. This together with early mineralization by bacteria likely helped to preserve these delicate fossils.”

In the new research, Dr. Fikáček, Dr. Qvarnström and their colleagues examined a fragmentary coprolite from the Upper Triassic beds of the Krasiejów locality in Poland.

They scanned the specimen using synchrotron microtomography, a method that visualizes internal structures in fossils in 3D with great contrast and resolution,

“So if you find an insect in the coprolite, you can scan it using microCT in the same way as we do with amber insects, and you can see all the tiny details of the insect body as we do in amber,” Dr. Fikáček said.

“In that aspect, our discovery is very promising, it basically tells people: Hey, check more coprolites using microCT, there is a good chance to find insects in it, and if you find it, it can be really nicely preserved.”

The researchers named the new beetle species Triamyxa coprolithica, which refers to its Triassic age and indicating that it belongs to the suborder Myxophaga – and the newly-established myxophagan family Triamyxidae — and that it was found in a coprolite.

The beetle likely lived in semiaquatic or humid environments and was likely consumed by Silesaurus opolensis.

“Although Silesaurus opolensis appears to have ingested numerous individuals of Triamyxa coprolithica, the beetle was likely too small to have been the only targeted prey,” Dr. Qvarnström said.

“Instead, Triamyxa coprolithica likely shared its habitat with larger beetles, which are represented by disarticulated remains in the coprolites, and other prey, which never ended up in the coprolites in a recognizable shape.”

“So it seems likely that Silesaurus opolensis was omnivorous, and that a part of its diet was comprised of insects.”

The team’s paper was published in the journal Current Biology.


Martin Qvarnström et al. Exceptionally preserved beetles in a Triassic coprolite of putative dinosauriform origin. Current Biology, published online June 30, 2021; doi: 10.1016/j.cub.2021.05.015


Thor's Hammer Mjolnir Caused The Extinction Of The Dinosaurs

Friday, July 2, 2021

The extinction of the dinosaurs is still hotly debated in the real world - but in Marvel Comics, it was caused by the creation of Thor's Mjolnir!

The creation of Thor's hammer Mjolnir caused the extinction of the dinosaurs in Marvel Comics. Nobody really knows for certain why the dinosaurs were wiped out. For millions of years, the dinosaurs ruled the Earth. And then, 66 million years ago, something happened. The dinosaurs were rendered extinct, vanishing - in geological terms - almost overnight.

The common theory is that this mass extinction event was caused by some sort of meteorite impact, one that potentially cracked the Earth's crust and led to sustained volcanic eruptions. Clouds of dust and ash swirled into the atmosphere, resulting in unprecedented climate change because sunlight could not reach the surface. Such a monumental event would naturally lead to extinction on a scale never seen before, because the catastrophe would happen so suddenly that few species would be able to evolve.

In the comics, the extinction of the dinosaurs was actually caused by the creation of Thor's hammer Mjolnir. In those ancient times, Odin the All-Father sought a weapon that could be used against the enemies of Asgard, and he had the great Dwarf craftsman Eitri create an enchanted hammer from a chunk of precious Uru. Eitri used the heart of a sun to forge a mold with which he could create this weapon, and the forging of this mold sent shockwaves throughout the cosmos. It nearly destroyed the smiths, shook all of Asgard, and sent chunks of fire down to the surface of the Nine Realms. Some of these struck Midgard, triggering a planetary apocalypse that rendered the dinosaurs extinct.

More detail is added to this story in Mighty Thor #12, which reveals what made that particular piece of Uru so powerful. Odin had confronted a cosmic threat sometimes called the God Tempest, a hurricane that swept through the stars with enough force to consume entire worlds. When the God Tempest approached Asgard, the All-Father had confronted it, and in the end Odin managed to contain the Mother of Storms within the chunk of Uru he had been gifted by the Dwarves. "I want you to forge it," Odin told the Dwarves. "Such power will be mine to wield. Make me a weapon, Dwarves, or the next time the Trolls invade your land... you can fight them yourselves."

And so that it was what the Dwarves of Nidavellir did. They created the greatest weapon in the history of Asgard, one that contained all the power of the God Tempest itself, and gave it to Odin the All-Father. The creation of Mjolnir came at a terrible price, ravaging all the Nine Realms, and changing the future of the Earth itself when those fireballs fell upon the planet. Ironically, Mjolnir proved unwilling to bend to Odin's will, and in the end he set it aside - for, though he did not know it, this weapon was not destined to be wielded by Odin, but by his son Thor.


Is Jurassic World: The Exhibition as Cool as Everyone Says? 3 Things You Need to Know.

Thursday, July 1, 2021

Jurassic World: The Exhibition is here! | Courtesy of Universal Studios

Dinosaurs in Texas? With Jurassic World: The Exhibition in Grandscape, you’d better believe it!

Jurassic World: The Exhibition opened on June 18, and has been making waves through social media ever since. This exhibition is an immersive 20,000-square-foot experience based on one of the biggest blockbusters in cinema history, the Jurassic Park film franchise.

But is it really worth all the hype?

Well, we braved the Velociraptors and checked it out for you. We walked away with 5 reasons why you might want to add Jurassic World: The Exhibition to your weekend to-do list!

Reason 1: It’s the closest you’ll get to experiencing real dinosaurs!

Welcome to jurassic world! | image courtesy of universal studios.

Fossils at a museum are awesome, don’t get us wrong. But they won’t roar at you. And they certainly won’t majestically welcome you through the exhibit gates like this noble, towering Brachiosaurus welcomes you to Jurassic World.

As a guest, you will begin your journey by walk through the world-famous gates, and embark on an adventure of encountering life-sized dinosaurs, and exploring richly themed environments.

You will be able to imagine what it would have been like to walk among these breathtaking creatures and even interact with new baby dinosaurs, including the adorable baby Ankylosaurus named “Bumpy” from the popular animated Netflix original series, Jurassic World: Camp Cretaceous.

Kids love all of the other baby dinosaurs that the knowledgeable handlers are carrying all around the exhibit!

Reason 2: You become part of the dinosaurs’ story and learn by walking their steps… literally!

These babies are everywhere. You’ve gotta get that baby dino selfie. | image courtesy of universal studios.

Walking through this exhibit at your own pace, you will encounter scenes from the beloved movies that have been recreated to thrill and entertain Jurassic Park lovers.

You will also encounter the Hammond Creation Lab, where you can observe baby dinos at each stage, from incubating eggs to the hatched babies sleeping in the hatchery. You can unlock the secrets of the history and science to bring these incredible back to life.

But beware.

What’s a trip to Jurassic World without just a little chaos? Watch your step at every corner… you might come face to face with Blue the Velociraptor (don’t panic! Her handler is usually never too far away), or you might even stumble upon the escaped Tyrannosaurus Rex!

Reason 3: If you’re playing the mobile AR game Jurassic World Alive, then you get a surprise!

Watch out for this big guy! He was pretty hungry-looking when we encountered him. | courtesy of universal studios.

If you play the popular mobile augmented reality game (Jurassic World Alive) on your phone, then you’re in for a bonus treat!

Players who visit the Exhibition in Dallas and open the game on their devices can locate an exclusive Jurassic World: The Exhibition incubator, which are capsules that contain valuable resources, as an in-game reward.

Players with AR-enabled devices can then snap a picture or take a video of a dinosaur using the game’s AR feature and post to their social media channels using the #JurassicWorldAlive hashtag.

AT A GLANCE – Jurassic World: The Exhibition

Tickets to the exhibit are on sale until January 2022, so go plan your visit now!

Tickets to Jurassic World: The Exhibition start at $29.50 for adults (16 years +) and $19.50 for youth (3- 15 years). Children two-years-old and younger are free with accompanying parent.

VIP packages are available, as well as special pricing for Senior citizens and military. Group sales packages are available for groups greater than 10. Read up on more ticket and guest wellness guidelines here.

For more information on planning your visit, check out


Discovery of "Fossil Graveyard" Shows What Life Looked Like 518 Million Years Ago

Friday, July 2, 2021

Chuandianella ovata, an extinct shrimp-like crustacean. Photo by Yunnan University

Have you often thought about traveling back in time and looking at how the Earth was millions of years ago? While time travel is not an available option at the moment, scientists have found the next best thing - a fossil deposit from over 500 million years ago with a diverse set of animals of that period.

The discovery was made near Kunming, in the southern province of Yunnan in China. The researchers from the Yunnan University and State Key Laboratory of Paleobiology in China and  Pennsylvania State University in the US have dated it back to the Cambrian period, approximately, 518 million years ago. The findings were recently published in Nature Ecology and Evolution.  

The deposit contains 2,846 specimens. It is not only the oldest found so far but is also the most diverse. It contains early vertebrates and other soft-bodied organisms who lived in the oceans. However, what has the researchers really excited is the presence of specimens in their larval and juvenile stages. "Juvenile fossils are something we hardly see, especially from soft-bodied invertebrates," Julien Kimmig, collections manager at the Earth and Mineral Sciences Museum and Art Gallery at Penn State University and one of the authors of the study said.  

The international team of researchers has identified 118 species so far in these deposits, 17 of which are new. These are ancestors of crustaceans, worms, trilobites, algae, sponges, modern-day insects, and early vertebrates. 

In the juvenile specimens, the researchers found the appendages to be intact and internal soft tissue can be seen. This is helping researchers learn about body parts in these animals, which have never been seen before. "The site preserved details like 3D eyes, features that have never really been seen before, especially in such early deposits," Sara Kimmig, assistant professor at Penn State University said.

The site of the fossil deposit is called the Haiyan Lagerstätte. A lagerstätte consists of several layers of sediment deposit where each layer is a burial event. Most of the deposits have been found in the lowest layer of this lagerstätte, which also showed the most diversity of species. The subsequent layers consist of other species, which the authors think is a representation of boom and bust periods in the ocean.

The authors hypothesize that the site might have offered protection from stronger ocean currents. Considering the high number of juvenile fossil specimens, an alternate hypothesis that is being considered is that these early organisms used the site as a paleonursery to protect their young ones from predators. A storm or sudden change in oxygen levels may have caused the sediment deposit leading to an extinction event. But if the site was indeed a paleonursery, then animal behavior hasn't changed much in over 500 million years. 

"The Haiyan Lagerstätte will be a wealth of knowledge moving forward for many researchers, not only in terms of paleontology but also in paleo-environmental reconstructions," said Sara Kimmig, who wants to analyze the sediments to understand the environmental conditions during the event.


Dinosaur Biodiversity Declined before Chicxulub Asteroid Impact: Study

Thursday, July 1, 2021

Condamine et al. analyze the speciation-extinction dynamics for six key dinosaur families, and find a decline across dinosaurs, where diversification shifted to a declining-diversity pattern 76 million years ago. Image credit: Jorge Gonzalez.

The most famous mass extinction was the disappearance of non-avian dinosaurs at the end of the Cretaceous period, 66 million years ago, after ruling the Earth for 170 million years. The best-supported extinction model is the impact of a large asteroid at Chicxulub, Mexico. However, it is widely debated whether dinosaurs were in decline or not before the Chicxulub impact. A study in the journal Nature Communications provides new evidence for an environmentally-driven global decline across dinosaur groups well before the asteroid impact.

“We looked at the six most abundant dinosaur families (Ankylosauridae, Ceratopsidae, Hadrosauridae, Dromaeosauridae, Troodontidae, and Tyrannosauridae) through the whole of the Cretaceous, spanning from 150 to 66 million years ago, and found that they were all evolving and expanding and clearly being successful,” said Dr. Fabien Condamine, a researcher at the Institut des Sciences de l’Evolution de Montpellier and CNRS.

“Then, 76 million years ago, they show a sudden downturn. Their rates of extinction rose and in some cases the rate of origin of new species dropped off.”

Dr. Condamine and colleagues used Bayesian modeling techniques to account for several kinds of uncertainties such as incomplete fossil records, uncertainties over age-dating the fossils, and uncertainties about the evolutionary models.

The models were each run millions of times to consider all these possible sources of error and to find whether the analyses would converge on an agreed most probable result.

“In all cases, we found evidence for the decline prior to the bolide impact,” said Dr. Guillaume Guinot, a researcher at the Institut des Sciences de l’Evolution de Montpellier and CNRS.

“We also looked at how these dinosaur ecosystems functioned, and it became clear that the plant-eating species tended to disappear first, and this made the latest dinosaur ecosystems unstable and liable to collapse if environmental conditions became damaging.”

“We used over 1,600 carefully checked records of dinosaurs through the Cretaceous,” added Professor Phil Currie, a paleontologist at the University of Edmonton.

“I have been collecting dinosaurs in North America, Mongolia, China, and other areas for some time, and I have seen huge improvements in our knowledge of the ages of the dinosaur-bearing rock formations.”

“This means that the data are getting better all the time. The decline in dinosaurs in their last ten million years makes sense, and indeed this is the best-sampled part of their fossil record as our study shows.”

“In the analyses, we explored different kinds of possible causes of the dinosaur decline,” said Professor Mike Benton, a paleontologist at the University of Bristol.

“It became clear that there were two main factors, first that overall climates were becoming cooler, and this made life harder for the dinosaurs which likely relied on warm temperatures.”

“Then, the loss of herbivores made the ecosystems unstable and prone to extinction cascade.”

“We also found that the longer-lived dinosaur species were more liable to extinction, perhaps reflecting that they could not adapt to the new conditions on Earth.”

“This was a key moment in the evolution of life,” Dr. Condamine said.

“The world had been dominated by dinosaurs for over 160 million years, and as they declined other groups began their rise to dominance, including the mammals.”

“The dinosaurs were mostly so huge they probably hardly knew that the furry little mammals were there in the undergrowth.”

“But the mammals began to increase in numbers of species before the dinosaurs had gone, and then after the impact they had their chance to build new kinds of ecosystems which we see today.”


F.L. Condamine et al. 2021. Dinosaur biodiversity declined well before the asteroid impact, influenced by ecological and environmental pressures. Nat Commun 12, 3833; doi: 10.1038/s41467-021-23754-0


Non-Avian Dinosaurs Nested in the Arctic, Paleontologists Say

Thursday, July 1, 2021

A pair of adult Nanuqsaurus tyrannosaurs and their young. Image credit: James Havens.

A team of paleontologists from the University of Alaska Fairbanks and Florida State University has uncovered the first convincing evidence that several types of dinosaurs, from small bird-like dinosaurs to giant tyrannosaurs, not only lived in what’s now Alaska during the Late Cretaceous period, but they also nested there.

“It wasn’t long ago that people were pretty shocked to find out that dinosaurs lived up in the Arctic 70 million years ago,” said Dr. Pat Druckenmiller, director of the University of Alaska Museum of the North and a researcher in the Department of Geosciences at the University of Alaska Fairbanks.

“We now have unequivocal evidence they were nesting up there as well. This is the first time that anyone has ever demonstrated that dinosaurs could reproduce at these high latitudes.”

Previous studies at a handful of other sites provided tantalizing bits of evidence that one or two species of indeterminate dinosaurs were capable of nesting near or just above the Arctic or Antarctic circle.

Environmental conditions at this time and place indicate challenging seasonal extremes, with an average annual temperature of about 6 degrees Celsius (about 40 degrees Fahrenheit).

There also would have been about four months of full winter darkness with freezing conditions.

“To find out that most if not all of those species also reproduced in the Arctic is really remarkable,” Dr. Druckenmiller said.

Dr. Druckenmiller and colleagues documented the ancient Arctic ecosystem of the Prince Creek Formation in Northern Alaska, including its dinosaurs, mammals, and other vertebrates.

They found hundreds of small baby dinosaur bones, including tiny teeth from individuals that were either still in the egg or had just hatched out.

The types of Arctic dinosaurs include small- and large-bodied herbivorous species including hadrosaurids (duck-billed dinosaurs), ceratopsians (horned dinosaurs and leptoceratopsians), thescelosaurs and carnivores (tyrannosaurs, troodontids, and dromaeosaurs).

Comparative sizes of immature and mature dinosaur teeth from Prince Creek Formation, Alaska. Image credit: Druckenmiller et al., doi: 10.1016/j.cub.2021.05.041.

“One of the biggest mysteries about Arctic dinosaurs was whether they seasonally migrated up to the North or were year-round denizens,” said Professor Gregory Erickson, a researcher in the Department of Biological Science at Florida State University.

“We unexpectedly found remains of perinates representing almost every kind of dinosaur in the formation. It was like a prehistoric maternity ward.”

Once they knew the dinosaurs were nesting in the Arctic, the scientists realized the animals lived their entire lives in the region.

Their previous research revealed that the incubation period for these types of dinosaurs ranges from three to six months.

“As dark and bleak as the winters would have been, the summers would have had 24-hour sunlight, great conditions for a growing dinosaur if it could grow quickly enough before winter set in,” said Dr. Caleb Brown, a paleontologist at the Royal Tyrrell Museum.

“Year-round Arctic residency provides a natural test of the animals’ physiology,” Professor Erickson said.

“We solved several long-standing mysteries about the dinosaur reign, but opened up a new can of worms. How did they survive Arctic winters?”

“Perhaps the smaller ones hibernated through the winter. Perhaps others lived off poor-quality forage, much like today’s moose, until the spring,” Dr. Druckenmiller said.

Paleontologists have found warm-blooded animal fossils in the region, but no snakes, frogs or turtles, which were common at lower latitudes. That suggests the cold-blooded animals were poorly suited for survival in the cold temperatures of the region.

“This study goes to the heart of one of the longest-standing questions among paleontologists: Were dinosaurs warm-blooded? We think that endothermy was probably an important part of their survival,” Dr. Druckenmiller said.

The team’s paper was published in the journal Current Biology.


Patrick S. Druckenmiller et al. Nesting at extreme polar latitudes by non-avian dinosaurs. Current Biology, published online June 24, 2021; doi: 10.1016/j.cub.2021.05.041