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Greek Experts Help Preserve Dinosaur Footprints in Beijing

Wednesday, October 17, 2018

Chinese and Greek staff working on scaffold to preserve dinosaur footprints at a geological park in Yanqing district of Beijing, Oct. 15, 2018. [Photo by Guo Xiaohong /]

"This is our second phase of work here," said Dr. Ilias Valiakos, UNESCO global geopark evaluator and vice director for Natural History Museum of the Lesvos Petrified Forest of Greece. He and his colleagues previously worked in Yanqing in May.

On that occasion, his team from the Natural History Museum of the Lesvos Petrified Forest of Greece started to clean the surface of the fossils on the slope and apply a special reagent to prevent weather damage, especially brought about by the rainy summer, and make them more visible to visitors.

"As we can see now, the methodology stood the rain test and proves effective," said Valiakos happily. This time, his team are completing the preservation work, during which they spotted several new dinosaur footprints on the 35-meter-high slope.

The footprints, first detected in Yanqing in 2011, are believed to have been left by dinosaurs living some 140 to 150 million years ago in the late Jurassic Period.

"Greece leads the world in fossil preservation and the exchange of knowhow and learning from their expertise help us improve our endeavor," said Zeng Guangge, a technical staff member in charge of preservation with the Yanqing geopark. "More importantly, we get to know and master the technology by working with these Greek experts, which is good for our future work as the preservation is an arduous, regular project."

Zeng said close cooperation and communication between the Yanqing and Lesvos UNESCO global geoparks had been enhanced since they signed an agreement in 2015 to include personnel training, people-to-people exchange and joint operation.

Besides guiding the field preservation, Valiakos had another job this time, of giving a lesson to local pupils in Yanqing on Oct. 15, to popularize geo-knowledge and explain the importance of protecting and conserving the dinosaur footprints and petrified plant fossils in their hometown.

"Only in this way can the geo-heritage be passed on from generation to generation," he said.

Valiakos and his team will visit Yanqing again next April to further promote the preservation project. "We will see what the treated-footprints will be like after the dry winter," he told


Ancient Steroid Suggests Sea Sponges Were One of Earth’s First Animals

Wednesday, October 17, 2018

A modern demosponge species, which makes the same 26-mes steroids that the researchers found in ancient rocks. Image: Paco Cárdenas

Scientists from the University of California, Riverside, are claiming to have discovered the oldest known animal fossil—an ancient sea sponge that emerged between 660 million and 635 million years ago.

New research published in Nature Ecology and Evolution describes a probable biomarker, or “chemical fossil,” linked to ancient sea sponges—a group of creatures considered to be among the earliest forms of animal life on the planet. The new evidence, presented by a UCR research team led by Gordon Love, suggests sea sponges emerged as early as 660 million years ago, during the Neoproterozoic Era, which is at least 100 million years before the Cambrian Explosion—a time when animal life expanded significantly in diversity and number.

But not everyone is convinced by this latest study. An expert we spoke with said these findings are far from conclusive.

Finding the world’s oldest fossilized animal is a kind of Holy Grail for paleontologists. Single-celled microbial life emerged around 3.5 billion years ago—a mode of life that persisted for thousands of millions of years. Then suddenly, at some point during the Neoproterozoic Era, complex, multicellular life emerged, giving rise to the three kingdoms we still see today: animals (also known as metazoans), plants, and fungi. By finding and studying the most ancient animal fossils on Earth, scientists hope to gain important new insights into the early processes of evolution, and even into how life might appear elsewhere in the galaxy.

Last month, an international team of researchers claimed to have discovered the world’s oldest fossil—a bizarre creature known as Dickinsonia, which first appeared around 571 million to 541 million years ago. The fossil evidence presented this appears to be a bit older, dating further back in time by around 100 million years. Interestingly, neither study provides traditional fossil evidence, that is, fossils containing the outlines of bones or soft tissue. Rather, these studies highlight the chemical traces left behind by ancient creatures. In the case of Dickinsonia, it was fat molecules; in the case of sea sponges, it’s a steroid compound known as a sterane. In both studies, the scientists claimed that these molecular signatures could only have been produced by animals.

“Molecular fossils are important for tracking early animals since the first sponges were probably very small, did not contain a skeleton, and did not leave a well-preserved or easily recognizable body fossil record,” study co-author J. Alex Zumberge said in a statement. “We have been looking for distinctive and stable biomarkers that indicate the existence of sponges and other early animals, rather than single-celled organisms that dominated the earth for billions of years before the dawn of complex, multicellular life.”

The new fossils were found in rocks and oil pulled from ancient formations in Oman, Siberia, and India. Chemical analysis revealed the presence of a steroid compound known as 26-methylstigmastane, or 26-mes for short. This distinctive chemical structure is only known to be produced by demosponges—a species of modern sea sponges. This is a strong indication for the presence of eukaryotic cells, i.e. multicellular organisms such as plants and animals, according to the researchers.

“This steroid biomarker is the first evidence that demosponges, and hence multicellular animals, were thriving in ancient seas at least as far back as 635 million years ago,” Zumberge said.

This is a critical discovery for the team, which produced similar results in 2009, but using a different steroid biomarker: 24-isopropylcholestane (24-ipc). This biomarker was discovered in rocks found in South Oman, and dated to about 650 million years ago. At the time, Love and his colleagues said the 24-ipc steroid could be linked to early eukaryotic life, but critics pointed out that the compound can also be produced by both demosponges and a few modern algae, throwing the findings into doubt. The new fossils contain traces of both 24-ipc and 26-mes, the latter of which is unique to demosponges, thus bolstering the case.

The new evidence is “the first animal-specific sterane marker detected in the geological record that can be unambiguously linked” to chemical signatures only known to come from demosponges, the authors conclude in their study. “These new findings strongly suggest that demosponges, and hence multicellular animals, were prominent in some late Neoproterozoic marine environments.”

It’s not shocking that sea sponges should be among the first forms of animal life on Earth. In a related study published in 2014, scientists combined genetics with paleontology to make a similar claim, saying early sponges emerged around 650 million years ago.

Jonathan B. Antcliffe, a senior researcher at Lausanne University in Switzerland, said the new study doesn’t prove anything.

“The biggest problem,” he says, is that the UCR scientists are claiming that the sterol is being made by the sponges alone. This is “contradicted by their own statements in the details of the supplementary information,” Antcliffe told Gizmodo, adding that fthis is “where all the skeletons are always hidden away.”

“In some places in the paper they rather carefully say that sterols have only been found in modern sponges, [but] this is rather different from saying that they are only made by modern sponges,” he said. “So digging through the supplementary information, they freely admit that the sterols in modern sponges could have been made by the sponges, that they could be made from symbionts inside the sponges, or they could be from something that the sponge had eaten. So there we are. As sponges eat everything from bacteria to metazoan zooplankton that doesn’t really help much to make this an exclusive statement of sponge affinities in deep time. As usual there is nothing here of real substance.”

When Antcliffe says “as usual,” he’s referring to his ongoing critiques of this work; it was he who pointed out, for example, that 24-ipc can be produced by algae. The new paper, it would appear, hasn’t changed his mind about this avenue of research.

Big claims require big evidence, and the hunt continues for definitive proof of the world’s oldest animal fossil.

[Nature Ecology and Evolution]


New Fossils of Ground Sloth-Like Dinosaur Could Help Reveal Why Sauropods Got So Big

Wednesday, October 17, 2018

Life restoration of Sarahsaurus aurifontanalis. Image credit: Brian Engh,

Sauropods are a group of plant-eating dinosaurs which exceeded all other terrestrial vertebrates in body size. A new, in-depth anatomical description of the best preserved specimens of Sarahsaurus aurifontanalis, a sauropod relative from North America, could help paleontologists with unraveling the mystery of why these dinosaurs got so big.

Sarahsaurus aurifontanalis lived in what is now Arizona about 185 million years ago (Early Jurassic period).

“This dinosaur preserves in its anatomy the anatomical changes that were happening in the Late Triassic and Early Jurassic that were occurring in the evolutionary lineage. It can help tell us how getting big happens,” said Dr. Adam Marsh, a paleontologist at Petrified Forest National Park.

The new anatomical description of Sarahsaurus aurifontanalis — made by Dr. Marsh and his colleague, Professor Timothy Rowe from the University of Texas at Austin Jackson School of Geosciences — is based on two skeletons from the Kayenta Formation of Arizona.

“The specimens are well preserved in 3D and remarkably complete, which is very rare in the fossil record,” said Dr. Matthew Brown, director of the Jackson School Museum of Earth History Vertebrate Paleontology Collections, who was not involved in the study.

“Such complete specimens help paleontologists better understand the fragmentary and incomplete fossils remains we typically find.”

Sarahsaurus aurifontanalis resembled a ground sloth. It stood upright, walked on its hind-legs and had powerful forelimbs with a large, curved claw capping the first finger of each hand.

It had a lot in common with the earliest sauropod ancestors — like walking on two legs — but it was also starting to show features that would foreshadow how its massive relatives would evolve — such as an increase in body size and a lengthening of the neck vertebrae.

“It’s starting to gain the characters of getting large compared to the earliest members of the group,” Dr. Marsh said.

Size and neck-length are features that sauropods would take to extremes as they evolved.

By studying these traits and others in Sarahsaurus aurifontanalis, and seeing how they compare to those of other dinosaurs, scientists can help reveal how these changes occurred across evolutionary history and how different dinosaurs relate to one another.

For example, the anatomical review helped clarify the relationship between Sarahsaurus aurifontanalis and two other sauropod relatives that lived in North America during the Early Jurassic: Anchisaurus polyzelus from the older Portland Formation of the Hartford Basin and Seitaad reussi from the younger Navajo Sandstone of Utah.

The paleontologists found that the three don’t have a common North American ancestor — instead they evolved from dinosaur lineages that came to North America independently.

The findings were published online October 10, 2018 in the journal PLoS ONE.


A.D. Marsh & T.B. Rowe. 2018. Anatomy and systematics of the sauropodomorphSarahsaurus aurifontanalis from the Early Jurassic Kayenta Formation. PLoS ONE 13 (10): e0204007; doi: 10.1371/journal.pone.0204007


‘Most Accurate’ Recreation of T. Rex Shows it Wasn’t Quite How it Was in Jurassic Park

Wednesday, October 17, 2018

‘Most accurate’ recreation of T-Rex shows it wasn’t quite how it was in Jurassic Park A little chubbier than everyone thought (Scott Hartman)

A team of palaeontologists have recreated Tyrannosaurus rex based on the most up-to-date research – and it’s a little different from what people imagined.

Tyrannosaurs would have been chubby, walking low to the ground, with a low centre of gravity, the researchers from the Mexico Museum of Natural History and Science.

The creature also had no feathers, say the artists, who used data from 20 scientific studies to recreate the 20-foot carnivore.

‘Most accurate’ recreation of T-Rex shows it wasn’t quite how it was in Jurassic Park It was reconstructed using 20 scientific papers (Picture Scott Hartman)

The researchers believe it may have had ‘plates’ of keratin in its back, based on similar patterns found in birds (the closest living relatives of dinosaurs).

Artist Scott Hartman who worked on the project said, ‘They worked from the skeleton up, spent months getting the muscles right, and the results are now available for everyone to see.The amount of time invested and attention to detail blew me away.

‘As with any reconstruction there are of course some details we can’t know, and competing interpretations that are equally likely. But I can honestly say this was the most exhaustive attempt at restoring an extinct animal that I’ve worked on.’


Zuul crurivastator: Meet The Dinosaur That’s Being Uncovered In Trenton

Tuesday, October 16, 2018

The fossilized skull of a Zuul crurivastator, which will go on display at the Royal Ontario Museum in December. (Brian Boyle/ROM)

If you’ve seen a dinosaur skeleton in a museum in the past 20 years, chances are you’ve seen the work of Research Casting International, a company that builds exhibits for museums around the world, including the Royal Ontario Museum, in Toronto.

The services it provides — which include the restoration, mounting, casting, and fabrication of dinosaur skeletons — require a mix of engineers, blacksmiths, paleontologists, and artists working at the intersection of science, history, and design.

“And brute strength. You can’t forget brute strength,” says Brett Crawford, head of mounting operations.

It’ll take more than mere brute strength, though, for the company to complete one of its biggest projects yet: preparing the 16,000-kilogram body block of Zuul crurivastator, a recently discovered species of ankylosaur, for display at the ROM this December.

The block — a mass of hard sandstone about two metres tall — contains the 75-million-year-old fossil of Zuul crurivastator (whose first name was inspired by a monster from the movie Ghostbusters and whose second name means “destroyer of shins,” a reference to the weaponized tail that scientists believe the dinosaur used to fend off predators). RCI employees chip away at the block with pneumatic air scribes (basically, pen-sized jackhammers), slowly revealing the dino bones.

Artist's drawing of Zuul crurivastator, a species of ankylosaur that was first discovered in Montana in 2014. (Danielle Dufault/ROM)

“It’s a remarkable skeleton. Probably the best-preserved club-tailed ankylosaur that’s ever been found, and it’s also one of the largest,” says David Evans, the paleontologist who helped name Zuul and who is head of dinosaur research at the ROM.

Evans explains that Zuul was found by accident in 2014, when an American team looking for a Gorgosaurus (a bipedal carnivore not unlike the more famous T. rex) in Montana unexpectedly hit it with a bulldozer. The fossil, which had been hidden beneath about 30 metres of rock, “never came close enough to the surface to experience modern erosion through freeze-thaw cycles or plant roots,” Evans adds. “And because it was trapped in this rock without being disturbed, it has just spectacular preservation.”

The ROM acquired the fossil in 2016, and since then, RCI employees have discovered other specimens within the body block. “It’s not just a dinosaur in isolation,” Evans says. “It’s an entire ecosystem that’s preserved in stone. It has fossils of everything from turtles, crocodiles, clams, snails, and a remarkable array of plants.”

Just a day before visited RCI, for example, one technician spotted what looked to be the jaw of a turtle. Further chiselling revealed the shell and limbs. Evans hopes it will prove to be another well-preserved fossil from the Cretaceous period.

Technicians at Research Casting International in Trenton meticulously chip away at a rock containing the Zuul fossil. (David Rockne Corrigan)

Emily Villars, a conservator tasked with whittling down the giant rock, says these incidental findings are the best part of the job: “It’s pretty awesome to come into work and be a part of discovering something new,” she says.

Research Casting International's replica of an Albertosaurus skull. (David Rockne Corrigan)

Brett Crawford has been with RCI for more than 20 years. When he first started, the company worked out of a 560-square-metre warehouse in Oakville. It’s grown since — the Trenton facility they moved into in 2007 is six times larger — but Crawford says not many people in Ontario realize that this kind of work is being done in the province.

“Heck, most people in Trenton don’t even realize we’re here,” he says.

This is one in a series of stories about issues affecting eastern Ontario. It's brought to you with the assistance of Queen’s University.

Ontario Hubs are made possible by the Barry and Laurie Green Family Charitable Trust & Goldie Feldman.


Dinosaur Expert Hopes New Technology Will Unearth ‘Elgin Reptiles’

Tuesday, October 16, 2018

Nick Fraser.

A leading expert on dinosaurs is hoping new technological advances will help solve the mystery of the “Elgin reptiles”.

Nick Fraser, a former Aberdeen University graduate, who is now Keeper of Natural Sciences at National Museums Scotland, has established himself as a globally-renowned palaeontologist.

He had made important findings in such diverse locations as the United States, China, and on Skye and in the Scottish Borders.

And now he is keen to discover more about the “internationally significant area” of Moray.

Mr Fraser, who is currently in New Mexico, said: “We’ve known since the nineteenth century about the so-called ‘Elgin reptiles’, in the sandstones around Elgin and Lossiemouth.

“These rather obscure fossils are generally nothing much to look at – in fact you would be forgiven for overlooking them completely.

“But these rocks and associated fossils range from around 230-260 million years old and so they are contemporaneous with the earliest of the dinosaurs.

“It has even been suggested that there is one of the world’s oldest dinosaurs in these rocks and we are looking to investigate this further.

“The advent of Computed Tomography (CT scanning) has opened up a whole new way of studying them.

“So there is now an opportunity to get much clearer images of these fossils which we expect will provide a much better understanding of them – and maybe we can confirm the Elgin dinosaur in the years ahead.”

Mr Fraser has led a number of major fossil excavations ranging from Jurassic dinosaurs in Wyoming and a major bone bed of 14 million-year-old whales in Virginia to aged plant fossils in northern China.

However, much of his recent work has been carried out on Skye.

He added: “It might seem a long way from places such as the Gobi desert or the famed deposits in northern China, but many of the rocks around Skye’s rugged coastline are Middle Jurassic in age.

“The fossils have been around for 140 million years and are in no hurry to give themselves up to enthusiastic palaeontologists.

“But, with patience and luck, we are beginning to appreciate that in the future, Skye will occupy an important place in the research of early lizards, dinosaurs and mammals.”


Giant 70 Million-Year-Old Dinosaur Skeleton Unearthed in Gobi Desert

Sunday, October 14, 2018

Professor Shinobu Ishigaki lying next to a dinosaur footprint in the Mongolian Gobi Desert

The fossil is believed to be the remains of a sauropod dinosaur, a member of the huge herbivorous species that lived on our planet millions of years ago.

A team of Japanese and Mongolian scientists has discovered a skeleton of a giant dinosaur in Gobi Desert in Mongolia, the Japan-based news agency Jiji reports.

The fossil is thought to belong to a 70 million-year-old sauropod dinosaur. Sauropods were long-necked, four-legged plant eaters that inhabited the Earth in the Jurassic and Cretaceous periods. This genus includes the largest creatures ever to walk the Earth; in particular, the colossal Argentinosaurus, which scientists believe to have been over 36 meters long and over 21 meters tall.

The dinosaur discovered in Gobi Desert was apparently smaller but still impressive: scientists have found a fossilized 1.55 meter-long thigh bone. They claim that this is one of the largest specimens unearthed in the geological layer from the Late Cretaceous Period in the desert.

Ledumahadi mafube is the first of the giant sauropodomorphs of the Jurassic. Credit: Wits University

The team has also separately discovered fossilized dinosaur footprints left by an ornithopod, a bipedal plant-eating dinosaur. They measured 0.85 meters in length and 1.15 meters in width, which is close to the largest dinosaur foot on record. The "Bigfoot" dinosaur likely was some 17 meters long — 5 meters larger than the famous carnivorous Tyrannosaur rex.


85 Million-Year-Old Sea Monster Found in Kansas

Sunday, October 14, 2018

Popularized in the hit movie "Jurassic World," the mosasaur has come back to life after an 85 million-year-old fossil of a newborn creature was discovered in Kansas.

A "neonate-sized Tylosaurus specimen" (a type of mosasaur), has been identified and examined, with researchers looking at broken bones, including its snout, braincase and upper jaw.

"Despite its small size, a suite of cranial characters diagnoses FHSM VP-14845 [the fossil's identification] as a species of Tylosaurus, including the elongate basisphenoid morphology," the study's abstract reads.

The creature, which could grow up to 42 feet when it reached adulthood, had an "estimated skull length of 30 [centimeters]," indicating its neonatal state. It was found in the Smoky Hill Chalk Member of western Kansas in 1991, LiveScience reports, but it was originally identified as a Platecarpus, a genus that could grow to almost 20 feet in length.

Dentigerous portion of tylosaurine premaxillae. A–B, FHSM VP-14845, Tylosaurus sp. in A, dorsal and B, ventral views. C, TMM 40092-27, Tylosaurinae, in ventral view. Broken lines in A and B indicate reconstructed outlines of the element. C based on Polcyn et al. (2008 Polcyn, M. J., G. L. Bell Jr., K. Shimada, and M. J. Everhart. 2008. (Credit: Takuya Konishi, Paulina Jiménez-Huidobro & Michael W. Caldwell)

The paper was written in August 2017 and finally published online, determining that it is indeed a Tylosaurus.

Other variants of mosasaur could reach up to 50 feet in length and are thought to have weighed as much as 30,000 pounds, with some referring to them as the "T. rex of the seas."

The study's lead researcher, University of Cincinnati assistant professor Takuya Konishi, was able to determine that the fossil was indeed a mosasaur after looking at its long snout and sharp teeth, a feature similar to modern-day orcas, according to LiveScience.

"Somewhat unexpectedly, both pairs of premaxillary teeth project anteriorly and laterally at the base, implying a procumbent nature atypical of tylosaurines," the study reads. "Also unusual are closely spaced first and second premaxillary teeth, where the second pair is also located posterolateral to the first pair."

Unlike dinosaurs, which laid eggs, mosasaurs gave birth to live young. The size of this newborn, which likely would have measured at around 7 feet, suggests it did not live long, Konishi said, according to LiveScience.

"I'm thinking that this came out and somehow, miraculously, it got preserved and then discovered," Konishi said.


Dinosaur Extinction Drove Pulses of Fish Diversification

Saturday, October 13, 2018

Selected 50-million-year-old microfossil fish teeth and shark scales (center) from the study site. The scale bar is 500 microns. Teeth imaged by E. Sibert on the Hull Lab Imaging System at Yale University.

A research team has found new evidence that fish rapidly evolved in two phases following the Cretaceous-Paleogene (K/Pg) mass extinction that occurred 66 million years ago.

The team, which included Yale’s Pincelli Hull, made the discovery by examining microscopic fish teeth preserved in sediments buried deep in the bottom of the Pacific Ocean. Elizabeth Sibert of Harvard led the research, which appears in the journal Proceedings of the Royal Society B.

“What most people don’t realize is that there is a huge number of fossils that capture changes across important events in the past, such as mass extinctions, but we often lack the technology to rapidly pull information from fossils,” Hull explained. “In my lab we’ve developed a way of rapidly extracting information about morphology from fossils. We worked with Dr. Sibert and colleagues to apply this method to the problem of understanding how the Cretaceous-Paleogene mass extinction affected fish evolution.”


Guess What These Young Dinosaurs Ate When Their Parents Weren't Looking

Saturday, October 13, 2018

Skeletal reconstruction of CMC VP14128 to scale with a mature D. carnegii (dark grey). Grey bones are missing, while those in ivory are those present in CMC VP14128. Skeletal reconstruction based on the Diplodocus by S. Hartman. Silhouettes by S. Hartman and PhyloPic, modifications made. Skeletal reconstruction of CMC VP14128 redrawn from D. carnegii skeletal by S. Hartman. Human scale is Andrew Carnegie at his natural height of 1.6 m. Skeletal and silhouettes to scale. (B) CMC VP14128 in right lateral view with accompanying schematic. (C) CMC VP14128 in left lateral view with accompanying schematic. Schematics by DCW. The four portions of the skull numbered on accompanying schematics. Lateral views and schematics to scale. a: angular, al: alisphenoid, aof: antorbital fenestra, d: dentary, f: frontal, h: hyoid, l: lacrimal, m: maxilla, n: nasal, oc: occipital condyle, os: orbitosphenoid, p: parietal, paof: preantorbital fenestra, pf: prefrontal, pm: premaxilla, po: postorbital, pro: prootic, q: quadrate, sa: surangular, sq: squamosal. L and r before bone denotes if it is left or right. Credit: Scientific Reports (2018). DOI: 10.1038/s41598-018-32620-x

Imagine a crew of hungry toddlers and kindergartners with unrestricted access to the kitchen. Would they gorge themselves on candy, chips and ice cream?

For a type of fast-growing youngster that lived 150 million years ago, the answer instead was a diverse, nutritious diet, rich in tender greens.

That finding resulted from the discovery of a rare juvenile dinosaur skull belonging to one of those familiar, long-necked plant-eaters called sauropods. Unlike adults of this particular species, called Diplodocus, the young dinosaur had two different kinds of teeth—pencil-like teeth in the front, and flatter, spatulalike chompers in the back.

The dino's dental diversity and narrow snout allowed it both to pick out the choicest shoots and chew them to extract as many nutrients as possible, said lead study author D. Cary Woodruff, a Ph.D. student at the Royal Ontario Museum and the University of Toronto.

Proper nutrition would have been essential to fuel fast growth for the animals, which hatched from a cantaloupe-size egg and reached a staggering 60 feet in length by the time they were teenagers, he said.

"We're thinking of it like a mouth with a Swiss Army knife," Woodruff said.

Adults, on the other hand, had only the pencil-like front teeth, set in a wider, vacuum-shaped snout, suggesting they raked up vegetation indiscriminately and swallowed it without chewing, said Woodruff, who collaborated with researchers from Princeton University and the Cincinnati Museum Center, among other institutions. And given their different diets, adult and juvenile sauropods likely were eating apart from one another, Woodruff and his coauthors wrote in the journal Scientific Reports.

Peter Dodson, a prominent University of Pennsylvania dinosaur expert who was not involved with the research, said the skull was an important find. He agreed that the young dinosaur's two kinds of teeth would have enabled the animal to feed itself—coupled with a narrow snout for selective extraction of the most tender, easy-to-digest plants.

Good thing, because if young sauropods had relied on their massive, 100-foot-long parents for handouts, they would have been in danger, said Dodson, a professor in Penn's School of Veterinary Medicine as well as its department of earth and environmental science.

"It seems like a pretty fair bet that there wasn't parental care," he said. "They could've been stepped on without the parent knowing it."

Dinosaur-hunters get excited when they find a sauropod skull, as the bones from the heads of these massive animals were delicate and often did not survive the ravages of time. As a result, many museum skeletons of Diplodocus and other sauropods are completed with a cast from the skull of a different dinosaur—sometimes not even the same species.

The skull Woodruff analyzed—found in a Montana quarry by study coauthor Glenn Storrs, of the Cincinnati Museum Center—is especially unusual for its completeness and the fact that it came from such a young animal.

Woodruff estimated that the creature was 2 to 4 years old when it died. Even at that tender age, its skull was already 9 inches long, with a body stretching at least 15 feet from head to tail.


More information: D. Cary Woodruff et al. The Smallest Diplodocid Skull Reveals Cranial Ontogeny and Growth-Related Dietary Changes in the Largest Dinosaurs, Scientific Reports (2018). DOI: 10.1038/s41598-018-32620-x