Dinosaur age bird discovery


This video from Saskatchewan, Canada is called Diving Birds in the Prairies: Late Cretaceous Hesperornithiformes.

From Nature:

Exquisite bird fossils reveal egg-producing ovary

Early avians lost one of two ovaries to take flight.

Brian Switek

17 March 2013

Palaeontologists have discovered the first fossilized traces of developing egg cells in ancient fossil birds, showing a significant trait that already 120 million years ago separate birds from their ancestors. Like modern birds, these ancestors already had reduced their working ovaries to one, setting them apart from their dinosaur cousins.

Zhonghe Zhou, a palaeontologist at the Chinese Academy of Sciences in Beijing, and colleagues studied a fossil specimen of Jeholornis — an early bird that retained archaic characteristics such as a long bony tail — as well as a pair of fossils that belong to the enantiornithines, another extinct group of birds. All three fossils, according to Zhou and co-authors, contain preserved ovarian follicles, delicate structures containing single egg cells that would have developed into eggs. The researchers present their findings online today in Nature.

“It took us a while to figure out what these strange circular structures actually represent,” says Zhou. The small structures might possibly have been seeds or tiny stones the birds had swallowed to grind food in their digestive system. But on the basis of the size, shape, and position of the rounded structures, the team ruled out the alternative explanations and interpreted them as ovarian follicles.

The researchers point out that the follicles all seem to be on the left side in the three birds, just as they are in their modern relatives. In contrast, the fossilized hips of an oviraptorosaur — a feathered, beaked, theropod dinosaur — contained two eggs, hinting that one egg developed in each oviduct and indicating that non-avian dinosaurs retained two functioning oviducts, similar to modern crocodiles.

Like their reptilian ancestors, ancient birds produced a greater number of eggs at a time than do modern birds. Had the Jeholornis’s follicles developed into eggs, she might have laid as many as 20 in a clutch, Zhou says. The two enantiornithine specimens would have laid five and twelve eggs, respectively.

Taking flight

But why did the reproductive plumbing change in birds? Jeholornis and the two enantiornithines were relatively close to the transition from non-avian dinosaurs to ‘avian dinosaurs‘, Zhou and colleagues say, suggesting that the switch to one oviduct seems to be correlated with the evolution of flight — something that biologists had long suspected.

Palaeontologist Thomas Holtz of the University of Maryland in College Park agrees that the size, shape and position of the rounded bodies are consistent with the interpretation as follicles, but notes that alternative hypotheses — such as arthropod, amphibian egg or plant fossils — can’t be ruled out just yet. “High-quality scanning-electron microscope scans of the objects might help resolve this,” he says.

Still, provided that the objects really are follicles, Holtz agrees that the fossils show an intermediate state between non-avian dinosaurs and modern birds, and that the presence of one active oviduct would be “loss of a redundant organ to save weight”.

First healed dinosaur wound discovery


From National Geographic:

Scarred Duckbill Dinosaur Escaped T. Rex Attack

A fossilized bite mark on a duckbill dinosaur indicates it survived a T. rex attack.

An illustration of a dinosaur biting an Edmontosaurus

Tyrannosaurus rex goes after a duckbilled dinosaur in this artist’s conception.

Illustration courtesy Robert DePalma

A fossilized scar

The scar. Photograph courtesy Robert DePalma

Ker Than

for National Geographic News

Published February 28, 2013

A scar on the face of a duckbill dinosaur received after a close encounter with a Tyrannosaurus rex is the first clear case of a healed dinosaur wound, scientists say.

The finding, detailed in the current issue of the journal Cretaceous Research, also reveals that the healing properties of dinosaur skin were likely very similar to that of modern reptiles.

The lucky dinosaur was an adult Edmontosaurus annectens, a species of duckbill dinosaur that lived in what is today the Hell Creek region of South Dakota about 65 to 67 million years ago. (Explore a prehistoric time line.)

A teardrop-shaped patch of fossilized skin about 5 by 5 inches (12 by 14 centimeters) that was discovered with the creature’s bones and is thought to have come from above its right eye, includes an oval-shaped section that is incongruous with the surrounding skin. (Related: ”‘Dinosaur Mummy’ Found; Have Intact Skin, Tissue.”)

Bruce Rothschild, a professor of medicine at the University of Kansas and Northeast Ohio Medical University, said the first time he laid eyes on it, it was “quite clear” to him that he was looking at an old wound.

“That was unequivocal,” said Rothschild, who is a co-author of the new study.

A Terrible Attacker

The skull of the scarred Edmontosaurus also showed signs of trauma, and from the size and shape of the marks on the bone, Rothschild and fellow co-authorRobert DePalma, a paleontologist at the Palm Beach Museum of Natural History in Florida, speculate the creature was attacked by a T. rex.

It’s likely, though still unproven, that both the skin wound and the skull injury were sustained during the same attack, the scientists say. The wound “was large enough to have been a claw or a tooth,” Rothschild said.

Rothschild and DePalma also compared the dinosaur wound to healed wounds on modern reptiles, including iguanas, and found the scar patterns to be nearly identical.

It isn’t surprising that the wounds would be similar, said paleontologist David Burnham of the University of Kansas Biodiversity Institute, since dinosaurs and lizards are distant cousins.

“That’s kind of what we would expect,” said Burnham, who was not involved in the study. “It’s what makes evolution work—that we can depend on this.”

Dog-Eat-Dog

Phil Bell, a paleontologist with the Pipestone Creek Dinosaur Initiative in Canada who also was not involved in the research, called the Edmontosaurusfossil “a really nicely preserved animal with a very obvious scar.”

He’s not convinced, however, that it was caused by a predator attack. The size of the scar is relatively small, Bell said, and would also be consistent with the skin being pierced in some other accident such as a fall.

“But certainly the marks that you see on the skull, those are [more consistent] with Tyrannosaur-bitten bones,” he added.

Prior to the discovery, scientists knew of one other case of a dinosaur wound. But in that instance, it was an unhealed wound that scientists think was inflicted by scavengers after the creature was already dead.

It’s very likely that this particular Edmontosaurus wasn’t the only dinosaur to sport scars, whether from battle wounds or accidents, Bell added.

“I would imagine just about every dinosaur walking around had similar scars,” he said. (Read about “Extreme Dinosaurs” in National Geographic magazine.)

“Tigers and lions have scarred noses, and great white sharks have got dings on their noses and nips taken out of their fins. It’s a dog-eat-dog world out there, and [Edmontosaurus was] unfortunately in the line of fire from some pretty big and nasty predators … This one was just lucky to get away.”

Mysterious Escape

Just how Edmontosaurus survived a T. rex attack is still unclear. “Escape from aT. rex is something that we wouldn’t think would happen,” Burnham said.

Duckbill dinosaurs, also known as Hadrosaurs, were not without defenses. Edmontosaurus, for example, grew up to 30 feet (9 meters) in length, and could swipe its hefty tail or kick its legs to fell predators.

Furthermore, they were fast. “Hadrosaurs like Edmontosaurus had very powerful [running] muscles, which would have made them difficult to catch once they’d taken flight,” Bell said.

Duckbills were also herd animals, so maybe this one escaped with help from neighbors. Or perhaps the T. rex that attacked it was young. “There’s something surrounding this case that we don’t know yet,” Burnham said.

Figuring out the details of the story is part of what makes paleontology exciting, he added. “We construct past lives. We can go back into a day in the life of this animal and talk about an attack and [about] it getting away. That’s pretty cool.”

Sexual selection and dinosaur fossils


Sexual dimorphism in the pterosaur Darwinopterus. (Credit: Image by Mark Witton)

From the University of Southampton in England:

Survival of the prettiest: Sexual selection can be inferred from the fossil record

Detecting sexual selection in the fossil record is not impossible, according to scientists writing in Trends in Ecology and Evolution this month, co-authored by Dr Darren Naish of the University of Southampton.

The term “sexual selection” refers to the evolutionary pressures that relate to a species’ ability to repel rivals, meet mates and pass on genes. We can observe these processes happening in living animals but how do palaeontologists know that sexual selection operated in fossil ones?

Historically, palaeontologists have thought it challenging, even impossible, to recognise sexual selection in extinct animals. Many fossil animals have elaborate crests, horns, frills and other structures that look like they were used in sexual display but it can be difficult to distinguish these structures from those that might play a role in feeding behaviour, escaping predators, controlling body temperature and so on.

However in their review, the scientists argue that clues in the fossil record can indeed be used to infer sexual selection.

“We see much evidence from the fossil record suggesting that sexual selection played a major role in the evolution of many extinct groups,” says Dr Naish, of the University’s Vertebrate Palaeontology Research Group.

“Using observations of modern animal behaviour we can draw analogies with extinct animals and infer how certain features improve success during courtship and breeding.”

Modern examples of sexual selection, where species have evolved certain behaviours or ornamentation that repel rivals and attract members of the opposite sex, include the male peacock‘s display of feathers, and the male moose’s antlers for use in clashes during mating season.

Dr Naish and co-authors state that the fossil record holds many clues that point to the existence of sexual selection in extinct species, for example weaponry for fighting, bone fractures from duels, and ornamentation for display, such as fan-shaped crests on dinosaurs. Distinct differences between males and females of a species, called ‘sexual dimorphism’, can also suggest the presence of sexual selection, and features observed in sexually mature adults, where absent from the young, indicate that their purpose might be linked to reproduction.

We can also make inferences from features that are ‘costly’ in terms of how much energy they take to maintain, if we assume that the reproductive advantages outweighed the costs.

Whilst these features might have had multiple uses, the authors conclude that sexual selection should not be ruled out.

“Some scientists argue that many of the elaborate features on dinosaurs were not sexually selected at all,” adds Dr Naish, who is based at the National Oceanography Centre, Southampton.

“But as observations show that sexual selection is the most common process shaping evolutionary traits in modern animals, there is every reason to assume that things were exactly the same in the distant geological past.”

Dinosaurs, why so many big species?


This video is called Dinosaur Evolution 1 of 5.

By Charles Q. Choi, LiveScience Contributor:

Dinosaurs Skewed Bigger Than Modern-Day Species, New Research Suggests

Published: 12/20/2012 10:12 AM EST on LiveScience

Dinosaurs as a group may have been skewed more toward giant species than modern-day creatures are, researchers say.

The findings, based on comparisons of size ranges among extinct and current species, shed light on just how different the world was during the age of dinosaurs, scientists added.

Dinosaurs included the largest animals ever to walk the Earth. The giants developed early within the dinosaur lineage, with massive, long-necked, long-tailed sauropods evolving by about 200 million years ago.

Although scientists have discovered many giant dinosaurs over the years, many researchers, including, paleontologist David Hone at Queen Mary University of London, assumed dinosaurs came in the same range of small and large species as modern animals do, “and it was just my familiarity with the larger ones that distorted my perception.”

“Turns out, nope, there really were tons and tons of big guys out there and not many little ones,” Hone told LiveScience.

Hone and his Queen Mary colleague Eoin O’Gorman, a community ecologist, analyzed the sizes of modern birds, reptiles, amphibians, fish and terrestrial mammals. They also looked at dinosaurs, the prehistoric winged reptiles known as pterosaurs, and terrestrial mammals that vanished before the modern era. [Gallery: Stunning Illustrations of Dinosaurs]

Skew toward giant

The investigators scanned past research on the sizes of thousands of animal species, including approximately 330 dinosaur species. They found that dinosaurs were dramatically skewed toward large sizes, a pattern significantly different from all other groups of animals they studied.

The most obvious question regarding this work is whether or not large dinosaur fossils survived more successfully than smaller ones, influencing the analysis.

“Indeed, large things do tend to be more readily preserved and smaller ones harder to find, so we would expect there to be a bias in the results towards larger species,” Hone said. “The question is, is that enough to affect our results?”

They don’t think so.

“First off, the differences are so colossal that the amount of small species missing would be truly enormous, and it’s unlikely we, as in the scientific community, have missed that many,” Hone said.

Indeed, paleontologists would have had to miss 99.99 percent of dinosaur diversity to explain the huge skew toward giant sizes that O’Gorman and Hone found.

In addition, this skew is not seen with the other extinct groups of animals the scientists examined, including. This includes the pterosaurs, which were close relatives of the dinosaurs and lived alongside them in similar environments.

Bigger is better?

Rather, the environments and biology of dinosaurs might explain this unique skew.

“As you get bigger, you get more energetically efficient, as being big gives you a longer digestion time and returns more energy from eaten food,” Hone said. “But mammals can’t get that huge or they would overheat.”

Mammals are endotherms, or “warm-blooded,” meaning they constantly generate their own heat. In contrast, big dinosaurs probably stayed warm because their enormous mass helped retain heat, just as large pots of hot water would take longer to cool down than smaller ones.

In addition, while mammals can have bigger and bigger young as they get larger, often growing their offspring inside themselves, “you can’t lay larger and larger eggs,” Hone said. The embryos inside eggs need the shells of eggs to be thin enough to allow them to breathe in oxygen and get rid of carbon dioxide, and if eggs grow too massive, the shells will not be strong enough to protect the eggs.

“So large dinosaurs still laid small eggs. That meant small babies.” The large number of eggs and small babies that big dinosaurs likely had suggests the roles that small species often play in environments may have been filled by the young of large species.

If these findings are true, they suggest the age of dinosaurs behaved in ways fundamentally different from the modern world.

“These must have been very harsh environments to live in, with some of the most efficient predators the planet has known,” O’Gorman said. Survival amid predators that preyed on the small likely involved producing many young with very rapid growth rates. [Image Gallery: Dinosaur Daycare]

O’Gorman noted this pattern of size ranges they discovered was different between herbivorous and carnivorous dinosaurs. The sizes of herbivorous dinosaur species were biased toward giants, while carnivorous dinosaurs had nearly as many smaller species as large ones. That is likely because the herbivorous lifestyle allows a larger size limit, so that the larger they get, the more energy they can get from digested food. The same apparently did not hold true of a carnivorous lifestyle — they could only get so big before they reached a maximum in terms of benefits.

In addition, this skew toward giant sizes generally happened toward the end of major time periods, such as the Late Triassic, Late Jurassic and Late Cretaceous. The researchers suggest the evolution of large body sizes among dinosaurs was the result of long exposures to stable environments, and was reset by the mass extinctions that occurred at the end of these periods.

A mystery that remains is why the researchers did not find this pattern in reptiles, amphibians or fish, which … like the giant dinosaurs were not endoderms. Although the vast majority of modern reptiles and amphibians are carnivores, many fish are herbivores.

“I would be very interested to explore the fish data more thoroughly, subdividing by herbivorous and carnivorous groups as we have done for the dinosaurs,” O’Gorman told LiveScience. “This may help to validate the dinosaur results further if we find a consistent trend.”

The scientists detailed their findings online Dec. 19 in the journal PLoS ONE.

Pre-dinosaur mesosaurs’ live birth


Despite the fact that the mesosaur embryos were dated to around 280 million years ago, researchers found them in a remarkably well preserved condition

From Discovery News:

Live Birth Predates Dinos

Analysis by Jennifer Viegas

Mon Dec 10, 2012 06:31 AM ET

Producing living young, and not external eggs, is a form of birth that could date back to 280 million years ago or even earlier, a new study suggests.

Called viviparity, this form of birth is used by humans, but clearly we were far from being the first to evolve it.

The study, published in the December issue of Historical Biology: An International Journal of Paleobiology, focuses on mesosaurs, which were among the world’s first aquatic reptiles. They lived in what are now South America and South Africa at a time when these two landmasses were united and part of the giant supercontinent Pangaea.

Mesosaurs, and even their earlier ancestors, possibly “were not able to produce hard shelled eggs, at least for the first several million years of their evolution,” lead author Graciela Piñeiro, a paleontologist at Uruguay‘s Facultad de Ciencias, told Discovery News. “After the recent discovery of mesosaur embryos, we can state with a high degree of confidence that embryo retention developed early in amniote evolution, given that mesosaurs are among the basal-most reptiles and that they date from the Early Permian around 280 million years ago.”

Piñeiro and colleagues Jorge Ferigolo, Melitta Meneghel and Michel Laurin recently discovered the exceptionally well-preserved mesosaur embryos at sites in Uruguay and Brazil. The environmental conditions at the locations allowed for the preservation of soft tissues, nerves and blood vessels, she said.

Giving birth in this manner and laying eggs each come with advantages and disadvantages. Eggs with hard, mineralized shells, such as those associated with today’s chicken eggs or those of dinosaurs, are believed to help reproduction on dry land. But many terrestrial animals, including humans, do not lay eggs, so there must be other benefits to viviparity.

“We think that the retention of the eggs may have appeared in amniotes as a useful strategy to avoid predation and increase survivorship chances for the embryos,” Piñeiro said.

Parental care often then follows. There is even some evidence that mesosaurs provided such care, because adults and juveniles have been associated together in the fossil record.

At least some mesosaurs even had the added challenge of giving birth and raising young in extremely salty water.

“In Uruguay, mesosaurs may have first colonized the shallow water environment of the Mangrullo Formation, which under the establishment of arid climatic conditions that increased evaporation became like a salty marsh where just a few opportunistic organisms could tolerate the anoxic bottom conditions generated by the accumulation of high amounts of organic matter,” Piñeiro explained.

When infant mesosaurs entered the world, they possibly even had a salt gland and other anatomical adaptations already in place, allowing them to survive the otherwise challenging conditions.

There is also compelling evidence that giant, carnivorous, four-flippered reptiles known as plesiosaurs gave birth to live young as well. Robin O’Keefe of Marshall University and team discovered a big embryonic marine reptile contained in the fossil of its 15.4-foot-long mother, which lived 78 million years ago.

“The embryo is very large in comparison to the mother,” O’Keefe said, “much larger than one would expect in comparison with other reptiles. Many of the animals alive today that give birth to large, single young are social and have maternal care. We speculate that plesiosaurs may have exhibited similar behaviors, making their social lives more similar to those of modern dolphins than other reptiles.”

Dinosaur discovery in Mexico


This video is called Duck-Bill Dino Parts Explained.

Not only news about maybe the oldest dinosaur ever discovered.

Also news about a comparatively late (upper Cretaceous) dinosaur; from Discovery News:

New Dino Had Giant Nose

by Jennifer Viegas

Thu Dec 6, 2012 12:33 PM ET

A new dinosaur with a large, prominent nose has been discovered in northern Mexico.

The duck-billed dinosaur, Latirhinus uitstlani (“lati” is Latin for “wide” and “rhinus” means nose in Greek), lived during the Late Cretaceous approximately 73 million years ago. Found in Coahuila state, it is described in the latest issue of Historical Biology: An International Journal of Paleobiology.

Its wide nasal cavity might have given it incredible smell-detecting ability.

“Also, it might have supported and provided enhanced space for a soft tissue structure, sort of like an inflatable bladder, for display, recognition and communication purposes in general,” lead author Albert Prieto-Márquez told Discovery News.

World’s oldest dinosaur discovery in Tanzania?


This video is called Dinosaur Evolution, 1 of 5.

From Discover magazine:

Scientists Discover the Oldest Dinosaur Yet…Maybe

By Breanna Draxler

December 6, 2012 11:13 am

Paleontologists in Tanzania have unearthed fossils from a new species of prehistoric reptile. The bones may have belonged to the world’s oldest dinosaur—or they may be from a reptile that kind of looks like a dinosaur.

Currently, the oldest confirmed dinosaur fossil dates back 230 million years. By this point in time, dinosaurs had grown in size and population to dominate the Earth. But when exactly did dinosaurs first enter the prehistoric picture, and how long did it take them to rise to such prominence? Paleontologists have narrowed the timeline down to the early or middle Triassic—the period of 20 million years before the oldest known dinosaur came to be.  The newfound species, dubbed Nyasasaurus parringtoni, predates this fossil by another 10 to 15 million years, and falls right in the middle of paleontologists’ projected timeframe for the first appearance of dinosaurs.

With only one upper arm bone and six vertebrae to work with, the researchers were able to glean a surprising amount of information about the newly discovered two-legged creature. It measured between 6 and 10 feet from head to tail, and only weighed between 45 and 130 pounds. Certain indicators in the fossils are unique to dinosaurs, namely an “elongated deltopectoral crest”—the attachment necessary to support strong chest muscles. Without more material the researchers cannot definitively declare the creature a dinosaur, rather than a silesaurid, the dinosaurs’ closest relative. Still, scientists say the fossils are the best available evidence of the presence of dinosaurs in the middle Triassic period, and regardless of how it ends up being classified, the new species offers a valuable view of the lives of early reptiles.

Image courtesy of Sterling J. Nesbitt, et. al.

A cross-section through the outer portion of the cortex shows the deltopectoral crest, among other indicators

Grand Canyon, from the dinosaur age?


This video from the USA is called National Geographic – Amazing Flight Over The Grand Canyon.

During the George W Bush administration, there was pressure on scientists to be silent on the fact that the Grand Canyon is much older than the few thousand years of the Great Flood mentioned in the Bible. That flood made the canyon, according to creationists.

All geologists agree that the Grand Canyon is older than five million years. They don’t agree on how much older it is.

Just a few years?

Is it twenty million years old?

Or still older? Today, from Associated Press:

December 3, 2012 at 1:00 am

Controversial study contends Grand Canyon old as dinosaur era

By Alicia Chang

Los Angeles — The awe-inspiring Grand Canyon was probably carved about 70 million years ago, much earlier than thought, a provocative new study suggests.

Using a new dating tool, a team of scientists came up with a different age for the gorge’s western section, challenging conventional wisdom that much of the canyon was scoured by the mighty Colorado River in the last 5 million to 6 million years.

Not everyone is convinced with the latest viewpoint published online last week in the journal Science. Critics contend the study ignores a mountain of evidence pointing to a geologically young landscape and they have doubts about the technique used to date it.

The notion that the Grand Canyon existed during the dinosaur era is “ludicrous,” said geologist Karl Karlstrom of the University of New Mexico in Albuquerque.

How the Grand Canyon became grand — with its vertical cliffs and flat plateaus — has been debated since John Wesley Powell navigated the whitewater rapids and scouted the sheer walls during his 1869 expedition.

Some 5 million tourists flock to Arizona each year to marvel at the 277-mile-long chasm, which plunges a mile deep in some places. It’s a geologic layer cake with the most recent rock formations near the rim stacked on top of older rocks that date back 2 billion years.

Doubting the process

Though the exposed rocks are ancient, most scientists believe the Grand Canyon itself was forged in the recent geologic past, created when tectonic forces uplifted the land that the Colorado River later carved through.

The new work by researchers at the University of Colorado Boulder and California Institute of Technology argued that canyon-cutting occurred long before that. They focused on the western end of the Grand Canyon occupied today by the Hualapai Reservation, which owns the Skywalk attraction, a horseshoe-shaped glass bridge that extends from the canyon’s edge.

To come up with the age, the team crushed rocks collected from the bottom of the canyon to analyze a rare type of mineral called apatite. The mineral contains traces of radioactive elements that release helium during decay, allowing researchers to calculate the passage of time since the canyon eroded.

Their interpretation: The western Grand Canyon is 70 million years old and was likely shaped by an ancient river that coursed in the opposite direction of the west-flowing Colorado.

Lead researcher Rebecca Flowers of the University of Colorado Boulder realizes not everyone will accept this alternative view, which minimizes the role of the Colorado River.

“Arguments will continue over the age of Grand Canyon, and I hope our study will stimulate more work to decipher the mysteries,” Flowers said in an email.

More number disputes

It’s not the first time that Flowers has dug up evidence for an older Grand Canyon. In 2008, she wrote a study that suggested part of the eastern Grand Canyon, where most tourists go, formed 55 million years ago. Another study published that same year by a different group of researchers put the age of the western section at 17 million years old.

If the Grand Canyon truly existed before dinosaurs became extinct, it would have looked vastly different because the climate back then was more tropical. Dinosaurs that patrolled the American West then included smaller tyrannosaurs, horned and dome-headed dinosaurs and duckbills.

If they peered over the rim, it would not look like “the starkly beautiful desert of today, but an environment with more lush vegetation,” said University of Maryland paleontologist Thomas Holtz.

Many scientists find it hard to imagine an ancient Grand Canyon since the oldest gravel and sediment that washed downstream date to about 6 million years ago and there are no signs of older deposits.

And while they welcome advanced dating methods to decipher the canyon’s age, Karlstrom of the University of New Mexico does not think the latest effort is very accurate.

See also here.

Horned dinosaur discovery in Canadian museum


This video is called Tribute to Ceratopsids.

By Michael Tutton in Canada:

November 8, 2012 | 4:05 am

Horned dinosaur discovery in Alberta

A piece of a fossilized reptilian horn that sat in an Ottawa museum for decades has led to the discovery of a new dinosaur species the size of a rhinoceros that roamed Alberta 80 million years ago.

Pieces of skulls from the recently named Xenoceratops were originally dug up from rocky sediments in southern Alberta sediments in 1958.

However, a pair of paleontologists rediscovered the bones a decade ago and gradually pieced together the sweeping neck plate of the four-footed, horn-headed giants.

Their work has been published in the October issue of the Canadian Journal of Earth Sciences.

The 3,000-kilogram creatures used their beak-like mouths to munch on plants and had a fearsome appearance due to a sweeping neck shield topped by two protruding spikes.

Canadian paleontologists Michael Ryan and David Evans say in their paper that the fossils were first discovered at a dig near Foremost, Alta., by American paleontologist Jann Langston Jr., who was working in Canada at the time.

They said Langston, now a professor emeritus at the University of Texas at Austin, left the bone fragments wrapped up and shelved in the Canadian Museum of Nature in Ottawa.

Evans said he and Ryan started to wonder in 2003 about two pieces of the neck shield — known as the frill — stored loosely in metal cabinets at the Ottawa museum. One was a spike and the other was an unusually large socket, he recalled.

He said the pieces aroused his curiosity in part because they came from rock formations that contained some of the oldest dinosaur fossils in Alberta.

That led them to investigate further in 2009, when they found Langston’s bone fragments from at least three animals, wrapped in a plaster and burlap casing. They were helped by Kieran Shepherd, curator of paleobiology for the Canadian Museum of Nature.

“Sure enough there was much more material and that was the key to identifying the new species,” Evans said in an interview.

The paleontologists took the fragments to the Royal Ontario Museum in Toronto, where they pieced together the metre-long piece of neck bone and then returned it to Ottawa.

They named the animal with the Greek words meaning “alien-horned face,” due in part to its unusual appearance.

Ryan, curator of vertebrate paleontology at the Cleveland Museum of Natural History, said he gradually learned that they had come upon the oldest known big-horned dinosaurs known as ceratopsids.

The herbivores are part of a family that later diversified, featuring a remarkable array of varying horn and frill configurations, said Ryan.

Orphaned bones like the ones they came across sometimes only make sense decades after they’re found, he added.

“The early fossil record of ceratopsids remains scant,” said Ryan. “This discovery highlights just how much more there is to learn about the origin of this diverse group.”

The scientists also suggest the size of the horns may have played a role in reproductive success — the bigger the horn, the more attractive they were to their female counterparts.

“We feel they were actually used for mate recognition. … We think the male dinosaurs with the biggest horns were the most reproductively successful,” said Ryan, though he added that this theory is a source of debate.

“It was that ornamental arms race on their skulls that drove the evolution.”

This dinosaur is just the latest in a series of new finds made by Ryan and Evans as part of their Southern Alberta Dinosaur Project, designed to improve knowledge of late Cretaceous dinosaurs and their evolution.

The project focuses on the paleontology of some of the oldest dinosaur-bearing rocks in Alberta, which is not as well studied as that of the famous badlands of Dinosaur Provincial Park and Drumheller.

See also here. And here.

Einiosaurus: here.