nandi's blog

Scientists Find Evidence Of Dinosaurs' Growth Patterns

Thursday, September 3, 2020

Research published in the journal Paleobiology is showing more about the life history of Maiasaura peeblesorum than any other known dinosaur. Credit: Holly Woodward

An international research team has discovered that dinosaurs developed yearly growth lines on their bones throughout their lives, a find that sheds light on growth patterns of the ancient animals.

Scientists from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) under the Chinese Academy of Sciences, together with the China University of Geosciences and the George Washington University, conducted the study and published it in the Journal of Vertebrate Paleontology.

Most modern mammals grow rapidly in their early years but develop dense lines of arrested growth in adulthood, a sign of cessation of growth. Modern reptiles, on the other hand, grow more slowly and keep growing throughout their lives, developing tree-ring-like growth lines on their bones every year.

According to the new research, dinosaurs may have followed growth patterns similar to those of modern reptiles.

The research team analyzed the bone tissues of Jeholosaurus, a small ornithopod dinosaur. They studied the specimens from five individuals at different growth stages, ranging from zero to five years old.

The research results showed that, while the growth rate of Jeholosaurus was obviously faster than that of modern reptiles, they also developed growth lines every year.

Environmental changes may be a cause of Jeholosaurus' particular bone histology, but more evidence is required in order to reach a conclusion, said Xu Xing at the IVPP, one of the authors of the study. Enditem


Using Math To Examine The Sex Differences In Dinosaurs

Friday, August 28, 2020

Credit: CC0 Public Domain

Male lions typically have manes. Male peacocks have six-foot-long tail feathers. Female eagles and hawks can be about 30% bigger than males. But if you only had these animals' fossils to go off of, it would be hard to confidently say that those differences were because of the animals' sex. That's the problem that paleontologists face: it's hard to tell if dinosaurs with different features were separate species, different ages, males and females of the same species, or just varied in a way that had nothing to do with sex. A lot of the work trying to show differences between male and female dinosaurs has come back inconclusive. But in a new paper, scientists show how using a different kind of statistical analysis can often estimate the degree of sexual variation in a dataset of fossils.

"It's a whole new way of looking at fossils and judging the likelihood that the traits we see correlate with sex," says Evan Saitta, a research associate at Chicago's Field Museum and the lead author of the new paper in the Biological Journal of the Linnean Society. "This paper is part of a larger revolution of sorts about how to use statistics in science, but applied in the context of paleontology."

Unless you find a dinosaur skeleton that contains the fossilized eggs that it was about to lay, or a similar dead giveaway, it's hard to be sure about an individual dinosaur's sex. But many birds, the only living dinosaurs, vary a lot between males and females on average, a phenomenon called sexual dimorphism. Dinosaurs' cousins, the crocodilians, show sexual dimorphism too. So it stands to reason that in many species of dinosaurs, males and females would differ from each other in a variety of traits.

But not all differences in animals of the same species are linked to their sex. For example, in humans, average height is related to sex, but other traits like eye color and hair color don't neatly map onto men versus women. We often don't know precisely how the traits we see in dinosaurs relate to their sex, either. Since we don't know if, say, larger dinosaurs were female, or dinosaurs with bigger crests on their heads were male, Saitta and his colleagues looked for patterns in the differences between individuals of the same species. To do that, they examined measurements from a bunch of fossils and modern species and did a lot of math.

Other paleontologists have tried to look for sexual dimorphism in dinosaurs using a form of statistics (called significance testing, for all you stats nerds) where you collect all your data points and then calculate the probability that those results could have happened by pure chance rather than an actual cause (like how doctors determine whether a new medicine is more helpful than a placebo). This kind of analysis sometimes works for big, clean datasets. But, says Saitta, "with a lot of these dinosaur tests, our data is pretty bad"—there aren't that many fossil specimens, or they're incomplete or poorly preserved. Using significance testing in these cases, Saitta argues, results in a lot of false negatives: since the samples are small, it takes an extreme amount of variation between the sexes to trigger a positive test result. (Significance testing isn't just a consideration for paleontologists—concerns over a "replication crisis" have plagued researchers in psychology and medicine, where certain studies are difficult to reproduce.)

Instead, Saitta and his colleagues experimented with another form of stats, called effect size statistics. Effect size statistics is better for smaller datasets because it attempts to estimate the degree of sex differences and calculate the uncertainty in that estimate. This alternative statistical method takes natural variations into account without viewing dimorphism as black-or-white-many sexual dimorphisms can be subtle. Co-author Max Stockdale of the University of Bristol wrote the code to run the statistical simulations. Saitta and his colleagues uploaded measurements of dinosaur fossils to the program, and it yielded estimates of body mass dimorphism and error bars in those estimates that would have simply been dismissed using significance testing.

"We showed that if you adopt this paradigm shift in statistics, where you attempt to estimate the magnitude of an effect and then put error bars around that, you can often produce a fairly accurate estimate of sexual variation even when the sexes of the individuals are unknown," says Saitta.

For instance, Saitta and his colleagues found that in the dinosaur Maiasaura, adult specimens vary a lot in size, and the analyses show that these are likelier to correspond to sexual variation than differences seen in other dinosaur species. But while the current data suggest that one sex was about 45% bigger than the other, they can't tell if the bigger ones are males or females.

While there's a lot of work yet to be done, Saitta says he's excited that the statistical simulations gave such consistent results despite the limits of the fossil data.

"Sexual selection is such an important driver of evolution, and to limit ourselves to ineffective statistical approaches hurts our ability to understand the paleobiology of these animals," he says. "We need to account for sexual variation in the fossil record."

"I'm happy to play a small part in this sort of statistical revolution," he adds. "Effect size statistics has a major impact for psychological and medical research, so to apply it to dinosaurs and paleontology is really cool."

Provided by Field Museum 


How to Install The Jurassic Park DLC for Minecraft

Tuesday, August 25, 2020

This guide will teach players the steps to installing the new Jurrasic World DLC for Minecraft Bedrock Edition, and how to create a world.

Dinosaurs are invading Minecraft in the form of a Jurrasic World DLC, and it adds content to the classic sandbox game that is larger than life. With new skins, items, and crafting recipes, there is plenty for players to explore in the Jurrasic World DLC.

The DLC adds more than 60 different dinosaurs to Minecraft along with 21 new skins. Players can raise their favorite dinosaurs from the Jurrasic Park films, or manage their own dino park. Players can use vehicles and NPCs to help solve disasters or go on expeditions to find new dinosaur DNA. The Jurrasic World DLC can be purchased from the Minecraft Marketplace for 1340 Minecoin or $7.99 USD.

How To Install Minecraft's Jurrasic World DLC

First off, the Jurrasic World DLC is only available in Minecraft Bedrock Edition. Players who are playing on consoles are playing on Minecraft Bedrock by default, but PC players will need to make sure they are playing on Bedrock and not Java. This is because DLC purchased through the Minecraft Marketplace can only be purchased and used on Bedrock Edition. Once players buy the DLC from the marketplace it will download and then be ready to use.

Players will then need to go to the main menu and click "play". They will then need to hit "create new" and a list of world templates will appear. The player needs to select the Jurrasic World template which will take them to the world customization screen. If the player does not want to change any setting they can hit create, otherwise, they can edit the options before heading into the dinosaur-filled park.

If the Jurrasic World template is not available in world templates, the player may need to manually download the DLC. They can do this by going back to the title screen and selecting "profile." Then click on the username in the top right corner. There should be a list of all the player's owned skins, worlds, and texture packs. Click on the Jurrasic World DLC and then hit "download." Players can also select "create this world" from this page to easily get back to the world creation page. After that, the player is all set to create, wrangle, and rescue some dinosaurs in the Jurrasic World DLC for Minecraft.

Minecraft Bedrock Edition is available on PC, Xbox One, PlayStation 4, Nintendo Switch, iOS, and Android devices.


Jurassic World Gave The T-Rex Revenge On The Spinosaurus

Wednesday, August 26, 2020

After Jurassic Park III put the Spinosaurus front and center, Jurassic World proved that no one beats the T-Rex and lives to tell the tale.

Jurassic World gave the T-Rex an act of well-deserved revenge over its infamous defeat by Jurassic Park III's Spinosaurus. In 2015, Jurassic World kicked off a new era of dinosaur mayhem fourteen years after Jurassic Park III got the poorest critical and financial reception of the franchise. Apart from the return to the touristic premise of the original Jurassic Park, the fourth installment upgraded the visual effects and raised the stakes with the Indominus Rex - a brand new, slaughterous, completely man-made dinosaur. But the prodigal son always comes home, and the sneaky addition of a clever reference to the film's climactic moment signaled the heroic comeback of the franchise's original icon when the Tyrannosaurus Rex enacts her revenge on the husk of Jurassic Park III's Spinosaur.

Jurassic Park III tried to shift the concept of the first two movies with a bigger focus on thrilling dinosaur action. The colossal Spinosaurus then became the movie's main antagonist, but instead of the instinctive ferocity of nature that was so gracefully represented in Jurassic Park's iconic T-Rex, this sadistic monster was hellbent on hunting down the main characters with the determination of a serial killer. To drive the point home, the movie pits its favored killing machine against the franchise's beloved mascot. In an infamous scene, the Spinosaurus brutally kills the T-Rex, prompting a feud among the most devoted dino-fans that still endures to this day.

In reality, the Spinosaurus was most likely the largest, deadliest carnivorous dinosaur to ever live, towering over other behemoths like the Giganotosaurus and casually snacking on sharks and crocodiles. However, no physical advantage can outshine the popularity of the fan-favorite T-Rex after it starred in the most memorable moments of the whole Jurassic Park franchise. That's why Jurassic World snuck in a nod to the infamous "Spinosaurus vs T-Rex" faceoff when the T-Rex from the first movie comes to help out in the film's final battle against the Indominus Rex. After the Indominus corners Owen Grady (Chris Pratt) in a souvenir shop, Claire Dearing (Bryce Dallas Howard) decides to open the T-Rex's gate as a last resort. She guides the emblematic dinosaur with a flare until it smashes through a Spinosaurus skeleton. Having obliterated it, the Queen of the Dinosaurs lets out a triumphant roar over the bones of her former contender.

Jurassic World's return to Isla Nublar reinforces the theme of human interference over the forces of nature for the sake of entertainment. This time around, the dinosaur-centered amusement park is even less worried about coming off as greedy since the previous catastrophic attempt to capitalize on the captivity of dinosaurs is a known failure. Still, the high probability of spilling human and animal blood for money is no hindrance to exhibits like the Spinosaurus's skeleton. But nature always prevails, and there isn't a clearer symbol than the T-Rex to prove it.

Jurassic World had plenty of callbacks to the original trilogy. Jurassic Park's cartoon mascot Mr. DNA and the statue of the late John Hammond (Richard Attenborough) are some of the most evident, but other details like the hologram of the Dilophosaurus - which alluded to the dinosaur who killed Dennis Nedry (Wayne Knight) in the original film and to the iconic kitchen scene - serve the story as metaphors for the movies going back to basics in a modernized sequel. After Jurassic Park III killed off the T-Rex in such a disappointing way, destroying the Spinosaurus' skeleton in the most spectacular fashion was the least the movie could do to compensate.


Fossils Reveal Diversity Of Animal Species Roaming Europe 2 Million Years Ago

Tuesday, August 25, 2020

Credit: Claire Terhune

A re-analysis of fossils from one of Europe's most significant paleontological sites reveals a wide diversity of animal species, including a large terrestrial monkey, short-necked giraffe, rhinos and saber-toothed cats.

These and other species roamed the open grasslands of Eastern Europe during the early Pleistocene, approximately 2 million years ago. Ultimately, the researchers hope the fossils will provide clues about how and when early humans migrated to Eurasia from Africa. Reconstructions of past environments like this also could help researchers better understand future climate change.

"My colleagues and I are excited to draw attention back to the fossil site of Grăunceanu and the fossil potential of the Olteţ River Valley of Romania," said Claire Terhune, associate professor of anthropology at the University of Arkansas. "It's such a diverse faunal community. We found multiple animals that hadn't been clearly identified in the area before, and many that are no longer found in Europe at all. Of course, we think these findings alone are interesting, but they also have important implications for early humans moving into the continent at that time."

About 124 miles west of the Romanian capital of Bucharest, the Olteţ River Valley, including the the important site of Grăunceanu, is one of Eastern Europe's richest fossil deposits. Many Olteţ Valley fossil sites, including Grăunceanu, were discovered in the 1960s after landslides caused in part by deforestation due to increased agricultural activity in the area.

Archeologists and paleontologists from the Emil Racoviţă Institute of Speleology in Bucharest excavated the sites soon after they were discovered. Fossils were recovered and stored at the institute, and scholarly publications about the sites flourished in the 1970s and 1980s. But interest in these fossils and sites waned over the past 20 to 30 years, in part because many records of the excavations and fossils were lost.

Since 2012, the international team, including Terhune and researchers from Romania, the United States, Sweden and France, has focused on this important fossil region. Their work has included extensive identification of fossils at the institute and additional field work.

In addition to the species mentioned above, the researchers identified fossil remains of animals similar to modern-day moose, bison, deer, horse, ostrich, pig and many others. They also identified a fossil species of pangolin, which were thought to have existed in Europe during the early Pleistocene but had not been solidly confirmed until now. Today, pangolins, which look like the combination of an armadillo and anteater and are among the most trafficked animals in the world, are found only in Asia and Africa.

The researchers' work was published in Quaternary International.

More information: Claire E. Terhune et al. Early Pleistocene fauna of the Olteţ River Valley of Romania: Biochronological and biogeographic implications, Quaternary International (2020). DOI: 10.1016/j.quaint.2020.06.020

Journal information: Quaternary International 

Provided by University of Arkansas


Paleontologists Find Massive Marine Reptile in Stomach of Triassic Ichthyosaur

Tuesday, August 25, 2020

Jiang et al report a fossil that likely represents the oldest evidence for predation on megafauna, i.e., animals equal to or larger than humans, by marine tetrapods — a thalattosaur in the stomach of a Middle Triassic ichthyosaur. Image credit: Jiang et al, doi: 10.1016/j.isci.2020.101347.

A new fossil of Guizhouichthyosaurus, a 5-m- (16.4-foot) long ichthyosaur that swam in Middle Triassic oceans some 240 million years ago, contains the remains of the 4-m- (13.1-foot) long thalattosaur Xinpusaurus xingyiensis, according to new research led by paleontologists from the University of California, Davis and Peking University. The work could be the oldest direct evidence that Triassic marine reptiles like ichthyosaurs — previously thought to be cephalopod feeders — were apex megapredators.

The ichthyosaurs were a group of marine reptiles that appeared in the oceans after the Permian mass extinction, about 250 million years ago.

They had fish-like bodies similar to modern tuna, but breathed air like dolphins and whales.

Like modern orca or great white sharks, they may have been apex predators of their ecosystems, but until recently there has been little direct evidence of this.

The new specimen of the ichthyosaur Guizhouichthyosaurus was discovered in Guizhou province, China, in 2010.

“We have never found articulated remains of a large reptile in the stomach of gigantic predators from the age of dinosaurs, such as marine reptiles and dinosaurs,” said University of California, Davis Professor Ryosuke Motani, co-lead author of the study.

“We always guessed from tooth shape and jaw design that these predators must have fed on large prey but now we have direct evidence that they did.”

Guizhouichthyosaurus was almost 5 m long, while its prey was about 4 m long, although thalattosaurs had skinnier bodies than ichythyosaurs.

The new specimen represents the oldest direct record of megafaunal predation by marine tetrapods and also sets the record for the largest prey size of Mesozoic marine reptiles at 4 m, which is larger than the previous record of 2.5 m (8.2 feet).

“Our ichthyosaur’s stomach contents weren’t etched by stomach acid, so it must have died quite soon after ingesting this food item,” Professor Motani said.

“At first, we just didn’t believe it, but after spending several years visiting the dig site and looking at the same specimens, we finally were able to swallow what we were seeing.”

“We now have a really solid articulated fossil in the stomach of a marine reptile for the first time,” he added.

“Before, we guessed that they must have eaten these big things, but now, we can say for sure that they did eat large animals.”

“This also suggests that megapredation was probably more common than we previously thought.”

The skeleton of Guizhouichthyosaurus and its stomach contents: (A) the specimen; (B) close-up of the stomach area, highlighted by red rectangle in (A); (C) line drawing to show selected bone elements of prey in (B); (D) 3D rendering showing the ventral side view of the bromalite, revealing two strings of vertebrae. Red triangles point at the vertebrae that can been seen from the top surface, and white triangles with red outlines mark three vertebrae that are hidden by the humerus. Yellow triangles point to the vertebrae of the second string. Abbreviations: cl – clavicle, color in dark orange; co – coracoid, in light orange; fe – femur, in tan; fi – fibula, in goldenrod; h – humerus, in blue; icl – interclavicle, in yellow; il – ilium, in dark green; isc – ischium, in purple; mt – metacarpal, and all possible digit elements in light purple; ns – neural spine, in light yellow; pu – pubis, in light green; r – radius, in light green; ti – tibia, in khaki; u – ulna, in light blue; v – vertebral centrum, in dark gold. Bones in dark gray and gray, ribs of thalattosaur Xinpusaurus xingyiensis. Bones in black, ribs, and gastralia of ichthyosaur Guizhouichthyosaurus. Scale bars – 25 cm in (A), 10 cm in (B and C), and 5 cm in (D). Image credit: Jiang et al, doi: 10.1016/j.isci.2020.101347.

Guizhouichthyosaurus’ last meal appears to be the middle section of Xinpusaurus xingyiensis, from its front to back limbs.

The predator has grasping teeth yet swallowed the body trunk in one to several pieces.

“Predators that feed on large animals are often assumed to have large teeth adapted for slicing up prey,” the paleontologists said.

Guizhouichthyosaurus had relatively small, peg-like teeth, which were thought to be adapted for grasping soft prey such as the squid-like animals abundant in the oceans at the time.”

Interestingly, a fossil of what appears to be the tail section of Xinpusaurus xingyiensis was found nearby.

“It’s clear that you don’t need slicing teeth to be a megapredator,” Professor Motani said.

Guizhouichthyosaurus probably used its teeth to grip the prey, perhaps breaking the spine with the force of its bite, then ripped or tore the prey apart.”

“Modern apex predators such as orca, leopard seals and crocodiles use a similar strategy.”

While the scientists now know that Guizhouichthyosaurus could eat animals as large as the thalattosaur, they don’t know if it killed this individual, or simply scavenged it.

“Nobody was there filming it,” Professor Motani said.

“However, there is reason to believe this was not a case of scavenging: modern marine decomposition studies suggest that if left to decay, the thalattosaur’s limbs would disintegrate and detach before the tail. Instead, we found the opposite in these fossils.”

The team’s paper was published in the journal iScience.


Da-Yong Jiang et al. Evidence Supporting Predation of 4-m Marine Reptile by Triassic Megapredator. iScience, published online August 20, 2020; doi: 10.1016/j.isci.2020.101347


Google’s Dinosaur Browser Game Gets A Dope Mod That Includes Double Swords

Tuesday, August 25, 2020

Why jump over cacti when you can chop them down?

Google’s hidden Dinosaur runner game that pops up in Chrome when people are offline is a treasured Easter egg for Chrome users, but it was arguably in need of an update.

Enter a modded version of the game called Dino Swords, created by a partnership between Internet collective MSCHF and 100 Thieves that gives the adorable, granulated T-Rex an assortment of weapons to use. Weapons are bound to various keys that players can use, but there’s a catch. Some of the weapons will lead to self-inflicted damage (I found out during one of my play-throughs of the modded version).

Google’s “Dino game is the final holdover from the golden age of things like Addicting Games and Miniclip games,” Daniel Greenberg, MSCHF’s head of strategy, told The Verge, adding that modding the game is “just making it truer to form.” That much feels true. With the modded update, the Dino game feels like a classic web browser game from an earlier era, when mini Flash games dominated the time I spent in the computer lab with friends.

Various weapons in Dino Swords / MSCHF

Dino Swords is our take on the classic Chrome dinosaur runner game, made extravagant with 26 weapons to help your runs,” Matthew “Nadeshot” Haag, 100 Thieves owner and CEO, said. “Many of them pay homage to classic video game weapons, some of them are totally OP, and some are completely useless. There’s even a few easter eggs that are pretty hard to unlock.”

The arsenal being introduced in the game is almost ridiculous, but the 100 Thieves team is hoping that people who play the game will put it goo use. There are “some awesome prizes for the people who are able to show they’re the best Dino Swords players in the world,” Nadeshot said in his statement, although it’s unclear what those prizes are. The Verge has reached out for more information.


How Dinosaur Research Can Help Medicine

Tuesday, August 25, 2020

This dinosaur skeleton, at 27 meters the longest ever exhibited in Europe, is currently on display at the Museum Koenig in Bonn. The ball-and-socket joint between two vertebrae can be seen next to the measuring tape. Credit: Martin Sander/Uni Bonn

The intervertebral discs connect the vertebrae and give the spine its mobility. The disc consists of a cartilaginous fibrous ring and a gelatinous core as a buffer. It has always been assumed that only humans and other mammals have discs. A misconception, as a research team under the leadership of the University of Bonn has now discovered: Even Tyrannosaurus rex could have suffered a slipped disc. The results have now been published in the journal "Scientific Reports."

Present-day snakes and other reptiles do not have intervertebral discs; instead, their vertebrae are connected with so-called ball-and-socket joints. Here, the ball-shaped end surface of a vertebra fits into a cup-shaped depression of the adjacent vertebra, similar to a human hip joint. In-between there is cartilage and synovial fluid to keep the joint mobile. This evolutionary construction is good for today's reptiles, because it prevents the dreaded slipped disc, which is caused by parts of the disc slipping out into the spinal canal.

"I found it hard to believe that ancient reptiles did not have intervertebral discs," says paleontologist Dr. Tanja Wintrich from the Section Paleontology in the Institute of Geosciences of the University of Bonn. She noticed that the vertebrae of most dinosaurs and ancient marine reptiles look very similar to those of humans -- that is, they do not have ball-and-socket joints. She therefore wondered whether extinct reptiles had intervertebral discs, but had "replaced" these with ball-and-socket joints in the course of evolution.

Comparison of the vertebrae of dinosaurs with animals still alive today

To this end, the team of researchers led by Tanja Wintrich and with the participation of the University of Cologne and the TU Bergakademie Freiberg as well as researchers from Canada and Russia examined a total of 19 different dinosaurs, other extinct reptiles, and animals still alive today. The researchers concluded that intervertebral discs not only occur in mammals. For these investigations, vertebrae still in connection were analyzed using various methods.

Surprisingly, Dr. Wintrich has now also been able to demonstrate that remnants of cartilage and even other parts of the intervertebral disc are almost always preserved in such ancient specimens, including marine reptiles like ichthyosaurs and dinosaurs like Tyrannosaurus. She then traced the evolution of the soft tissues between the vertebrae along the family tree of land animals, which 310 million years ago split into the mammalian line and the dinosaur and bird line.

Intervertebral discs emerged several times during evolution

It was previously unknown that intervertebral discs are a very ancient feature. The findings also show that intervertebral discs evolved several times during evolution in different animals, and were probably replaced by ball-and-socket joints twice in reptiles. "The reason why the intervertebral disc was replaced might be that it is more susceptible to damage than a ball-and-socket joint," says Dr. Wintrich. Nonetheless, mammals have always retained intervertebral discs, repeating the familiar pattern that they are rather limited in their evolutionary flexibility. "This insight is also central to the medical understanding of humans. The human body is not perfect, and its diseases reflect our long evolutionary history," adds paleontologist Prof. Dr. Martin Sander from the University of Bonn.

In terms of research methods, the team drew not only on paleontology, but also on medical anatomy, developmental biology and zoology. Under the microscope, dinosaur bones cut with a rock saw and then ground very thinly provide information comparable to histological sections of fixed and embedded tissue of extant animals. This makes it possible to bridge the long periods of evolution and identify developmental processes. Prof. Sander remarks: "It's truly amazing that the cartilage of the joint and apparently even the disc itself can survive for hundreds of millions of years."

Dr. Wintrich, who now works at the Institute of Anatomy of the University of Bonn, is pleased about the cooperation between the fields that has made this interdisciplinary understanding possible in the first place: "We found that even Tyrannosaurus rex was not protected against slipped discs." Only bird-like predatory dinosaurs then evolved ball-and-socket joints as well and saddle joints, still seen in today's birds. Likewise, such ball-and-socket joints were a decisive advantage for the stability of the spine of the largest dinosaurs, the long-necked dinosaurs.

This bridge between paleontology and medicine is seminal in Germany. The anatomist Prof. Dr. Karl Schilling from the University of Bonn, who was not involved in the new study, reports: "In the USA, in contrast, dinosaur researchers and evolutionary biologists are often closely involved in medical training, especially in anatomy and embryology. This gives young doctors a perspective that is becoming increasingly important in a rapidly changing environment."

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Story Source:

Materials provided by University of BonnNote: Content may be edited for style and length.

Journal Reference:

  1. Tanja Wintrich, Martin Scaal, Christine Böhmer, Rico Schellhorn, Ilja Kogan, Aaron van der Reest, P. Martin Sander. Palaeontological evidence reveals convergent evolution of intervertebral joint types in amniotesScientific Reports, 2020; 10 (1) DOI: 10.1038/s41598-020-70751-2


Jurassic Park: All 6 Dinosaurs That Appear In The First Movie Explained

Monday, August 24, 2020

The first movie in the Jurassic Park franchise includes a half-dozen different dinosaur species. Here's a breakdown of each and every one.

Here's a breakdown of all the different dinosaur species featured in the first Jurassic Park movie. Since the earliest days of cinema, filmmakers have always had a fascination with the terrible lizard, and understandably so: the prehistoric reptiles lend themselves to all manner of big screen spectacle. Going back to their appearances in Winsor McCary's 1914 animated short Gertie the Dinosaur and D.W. Griffith's live-action Brute Force (which premiered the same year), dinosaurs were commonly portrayed as mindlessly blood-thirsty monsters in the beginning, especially in black and white classics like King Kong. It wasn't until decades later that dinosaurs were depicted in a more empathetic light, particularly in animated movies like Don Bluth's The Land Before Time.

Released in 1993, Steven Spielberg's adaptation of Michael Crichton's best-selling sci-fi novel Jurassic Park not only brought dinosaurs to life in live-action with heretofore-unseen realism, it also showed how they could be both terrifying and majestic, often at the same time. The film was a massive success across the board, becoming the highest-grossing movie ever at the time of its release and winning the favor of critics with its story of scientific hubris and the power of creation. It's since given rise to a multi-billion dollar franchise spanning multiple installments, including a sequel trilogy set to conclude with the upcoming Jurassic World: Dominion.

In light of the property's expanding scale and scope, it's easy to forget the original Jurassic Park only includes appearances by a half-dozen dinosaurs, and some of them only show up in a single scene. Today, we're running down all six species and the roles they play in the movie's plot.


There are few dinosaurs more closely associated with the Jurassic Park franchise than the Velociraptor, an extremely cunning carnivore capable of doing everything from learning how to open doors to (as seen in the Jurassic World trilogy) following commands from humans, if trained correctly. In truth, the version of the Velociraptor featured in both the first Jurassic Park book and movie was primarily based on another member of the dromaeosaurid family, the Deinonychus, in terms of both their physical appearance and behavior. They also lack the feathers Velociraptors are now known to have, while still possessing the creature's infamous sickle-shaped claw for hunting.

It's the Velociraptors that actually set the plot for Jurassic Park the movie in motion. When one of them kills a park employee while being transported to their holding pen, the park's investors demand the park be inspected by a group of scientific experts who can weigh in on its safety (or lack thereof). Because the raptors are too dangerous to be kept outside of their heavily-fortified enclosure, they're stuck in their pen when the rest of the park's security facilities are shut-down by the park's head computer programmer, Dennis Nedry, in an act of industrial sabotage. However, when the park's entire security system is later turned off in order to be rebooted, it gives the deadly creatures the opportunity to escape and spend the third act hunting the movie's heroes.


One of the many things people love about Jurassic Park is the way it takes the time to capture the splendor and awe of dinosaurs (when it's not making them seem absolutely terrifying, that is). There may be no better example of this than the iconic scene where Dr. Grant, Sattler, and Malcolm get their first glimpse of a living, breathing dinosaur in the form of the herbivorous Brachiosaurus. The gentle creature offers a reprieve from the action later on during the movie, when Grant, Tim, and Lex encounter one of them after spending the night in a treetop, as well as some light-hearted comedy when it sneezes upon an unsuspecting Lex. Standing at a height of upwards of 70 feet (with a disproportionately long neck) and weighing as much as 64 short tons, one imagines most people would be just as wonder-struck seeing one of them in real-life.


Considering how prevalent and popular the herbivorous Triceratops is in pop culture, it's no wonder dino-fanatics were aghast when a study was published in 2010, claiming the dinosaur was really just a less mature version of the ceratopsid Torosaurus. The claim was subsequently disputed based on additional evidence, so the reputation of everyone's favorite three-horned, four-legged, plant-eating dino remains intact to this day. As for the creature's importance to Jurassic Park: the movie's heroes famously encounter a sick Triceratops during their tour of the titular park, making it the only dinosaur they actually see on the tour. It's a quietly-moving scene (particularly when Grant lies his head upon the creature's side as it breathes) and a good reminder that dinosaurs are more than just unfeeling eating machines.

Tyrannosaurus Rex

Outside of the Velociraptor, the carnivorous Tyrannosaurus rex is probably the dinosaur many people think of first when Jurassic Park is brought up. A bipedal meat eater with (seemingly) disproportionately small forelimbs, the T-rex is believed to have had the strongest bite force among terrestrial animals in real-life, and is certainly talented at chomping down on things in Spielberg's movie. The film plays fast and loose with what the actual T-Rex could and couldn't do (see also: when Grant famously claims the creature's vision is based on movement), and the debate about whether they were a predator, scavenger, or both rages on. For the purposes of Jurassic Park, however, the T-Rex is very much a fan of hunting its food, as Grant observes at one point.

Interestingly, from a storytelling perspective, the T-Rex has always walked the line between acting as an antagonist and ally to the humans in the Jurassic Park franchise. This all goes back to the original movie, where the T-Rex initially breaks loose (after the park's security facilities are turned off) and kills the lawyer Donald Gennaro, severely injures Malcolm, and nearly eats Grant, Lex, and Tim. Towards the very end of the film, though, the creature comes to Grant and the other's aid by attacking two of the remaining Velociraptors, just as they're about to have themselves a human sandwich. It's a great plot twist and set the stage for the T-Rex to act as a chaotic neutral force in the many sequels to come.


As cool as the Dilophosaurus' ability to spit venom and expand a cowl around its neck are in Jurassic Park, the actual dinosaur couldn't do either of those things. The real Dilophosaurus was nevertheless a carnivore like its onscreen counterpart, and is believed to have been one of the first large predatory dinosaurs on the North American continent when it was alive (with a slender build close to 25 feet in length and weight approaching 900 pounds). In Spielberg's movie, the dinosaur is a no-show on the heroes' tour, only to pop up later when Nedry crashes his vehicle while trying to flee the island, and proceeds to spit venom in his eyes before eating him alive. It's one of the most horrifying sequences in the entire film - and a scene that shows why it's good to take creative liberties sometimes.


Out of the all the dinosaurs that make an onscreen appearance sometime during Jurassic Park, the Gallimimus probably has the smallest impact on the story. That's not to say the one-off scene where Grant, Lex, and Tim encounter a herd of the creatures is unimpressive or pointless. Far from it, it's an exciting moment where the speedy bipedal dinosaurs (which were probably some of the fastest dinosaurs, capable of running up to 30 miles per hour, and believed to be omnivores that subsisted on things like smaller animals and insects) nearly trample over the heroes in their efforts to flee the T-Rex, who still manages to catch and snack on one of them. But more than being a showcase for some then cutting-edge CG effects, it's an encounter that reminds Grant and the others to get a move on and find their way the heck off Isla Nublar already.


New Study Helps Explain How Dinosaur Skeletons Supported Massive Loads

Saturday, August 22, 2020

Life reconstruction of Kamuysaurus japonicus, a species of hadrosaurid (duck-billed) dinosaur that lived some 72 million years ago (Cretaceous period) in what is now Japan. Image credit: Kobayashi et al, doi: 10.1038/s41598-019-48607-1.

A team of paleontologists and mechanical and biomedical engineers has compared CT scans of the fossilized bones of hadrosaurs and other dinosaurs with bones of extinct and living mammals and found that the dinosaur trabecular bone architecture was uniquely capable of supporting large weights (up to 47,000 kg) and different than that of mammals and birds.

The largest terrestrial dinosaurs were enormous creatures whose body mass placed massive gravitational loads on their skeleton.

Previous studies investigated dinosaurian bone strength and biomechanics, but the relationships between their trabecular bone architecture and mechanical behavior had not been studied until now.

“The structure of the trabecula, or spongy bone that forms in the interior of bones we studied is unique within dinosaurs,” said study co-author Dr. Tony Fiorillo, a paleontologist in the Huffington Department of Earth Sciences at Southern Methodist University.

“The trabecular bone tissue surrounds the tiny spaces or holes in the interior part of the bone such as what you might see in a ham or steak bone.”

“Unlike in mammals and birds, the trabecular bone does not increase in thickness as the body size of dinosaurs increase. Instead it increases in density of the occurrence of spongy bone.”

“Without this weight-saving adaptation, the skeletal structure needed to support the hadrosaurs would be so heavy, the dinosaurs would have had great difficulty moving.”

Dr. Fiorillo and colleagues used engineering failure theories and allometry scaling to analyze CT scans of the distal femur and proximal tibia of several dinosaur species: a troodontid, a caenagnathid, an ornithomimid, a therizinosaur, and two hadrosaurs (Edmontosaurus annectens and Edmontosaurus regalis).

“Our team is the first to use these tools to better understand the bone structure of extinct species and the first to assess the relationship between bone architecture and movement in dinosaurs,” they said.

The researchers then compared their findings to scans to extinct and living mammals, such as the Java mouse deer, the domestic sheep, the Siberian tiger, the white rhinoceros, the Asian elephant and the Columbian mammoth.

“Understanding the mechanics of the trabecular architecture of dinosaurs may help us better understand the design of other light-weight and dense structures,” said study lead author Dr. Trevor Aguirre, a researcher in the Mechanical Engineering Department at Colorado State University.

The findings were published in the journal PLoS ONE.


T.G. Aguirre et al. 2020. Differing trabecular bone architecture in dinosaurs and mammals contribute to stiffness and limits on bone strain. PLoS ONE 15 (8): e0237042; doi: 10.1371/journal.pone.0237042