Dinosaurs 'hunted in packs'

Experts had thought only herbivores roamed in herds

November 25, 2000 - BBC

Palaeontologists have unearthed evidence in support of a controversial theory: that large, meat-eating dinosaurs hunted in packs.

Experts had always thought that only plant-eating dinosaurs roamed in herds.

The giant herbivores would have lived, walked and died together, based on evidence gleaned from dinosaur graveyards and fossilised footprints.

But now palaeontologist Dr Phil Currie, from the Royal Tyrell Museum, Alberta, Canada, has discovered two fossil bone-beds, buried for millions of years, showing groups of massive carnivorous dinosaurs.

In an interview for the BBC Television series Horizon, he said the new finds were good evidence that huge meat-eating dinosaurs did hunt together in packs.

'Social groups'

The first site, in Alberta, Canada, contained the bones of at least 12 large carnivorous tyrannosaurs, including young and old.

Remains of at least six giant meat-eaters were found at a second bone-bed in Patagonia, South America.

Dr Currie told the BBC: "It seems to me that we have very convincing evidence that large meat-eating dinosaurs formed these social groups where the young and the old worked together, hunted together and lived together."

But some experts remain sceptical. They say that the sites could have been predator traps, where animals sank into sticky molten tar bubbling up from deep within the Earth.

Or floodwaters spreading across the plains could have washed together the remains of several unrelated dinosaurs.

Buried in the same place millions of years ago, the bones might look like a pack when unearthed today.

Angela Milner of London's Natural History Museum said: "A collection of bones in a bone-bed doesn't automatically mean we're looking at a collection of animals that lived together.

"Sometimes bone beds accumulate from large areas of the land where floods have brought all kinds of animal remains together and mixed them up."

The two new discoveries also raise another intriguing possibility. In most parts of the world, the largest meat-eaters and the largest herbivores never walked the Earth at the same time.

The giant long-necked plant-eating dinosaurs died out in the northern continents around 100 million years ago.

But plant-eaters like the massive Argentinosaurus lived on in the South. And recent fossil finds suggest that fearsome predators like Giganotosaurus, bigger than Tyrannosaurus Rex, were also around at the same time in South America.

Bones of the two giants have been found only 80 kilometres apart.

Which means that in prehistoric South America, because of a quirk of evolution, the largest meat-eaters could have fought the largest herbivores in a Clash of the Titans.

New Species of Dinosaur Discovered

The fierce predator stalked the swamps.

November 10, 2000 - Reuters

Italian paleontogists said Thursday they have identified a new species of dinosaur, which lived 200 million years ago and is one of the oldest meat-eating reptiles ever discovered.

According to fossil fragments found in a quarry in northern Italy, the dinosaur was 26.4 feet long, had a long neck and weighed over a ton, Giorgio Teruzzi, supervisor of paleontology at Milan's Museum of Natural History, told The Associated Press. Each of its sharp teeth measured 2.8 inches, he said.

It is believed to have lived in the early Jurassic era, usually associated with more primitive forms of carnivorous dinosaurs. The Jurassic era lasted from 208 to 140 million years ago.

``It is the world's oldest three-fingered dinosaur, and one of the oldest overall,'' one of the researchers, Cristiano Dal Sasso, said in an interview.

The dinosaur, tentatively called Saltriosaur after the name of the quarry where the fossils were found, is very similar to another predator, the American Allosaur, but is believed to be 20 million years older.

``What's interesting about this dinosaur is that it is more specialized, it is closely related to the more advanced species,'' said Thomas R. Holtz, a paleontologist at the Department of Geology at the University of Maryland at College Park.

The fossils were found entombed in a limestone block in a quarry in Saltrio, north of Milan near the Swiss border, in 1996. Researchers started studying them only last year.

They include more than a hundred bone fragments, the longest measuring 16 inches - altogether less than 10 percent of the entire skeleton. One tooth was also found.

Holtz said that 200 million years ago was a critical time for the evolution of meat-eating dinosaurs. It was then that they started evolving into truly fierce predators.

``This specimen will be helpful in terms of the reconstruction of the dinosaurs' history and interrelations between various groups,'' Holtz said.

The Saltriosaur fossils will go on display Friday at Natural History museums in both Milan and Besano, near the quarry.

Dig pulls up five T. rex specimens

C-rex could be even bigger than Sue

Oct. 10, 2000 - BBC

The discovery of five Tyrannosaurus rex skeletons during a single summer dig in the United States could mean these creatures were more common than previously believed, according to the leader of the project.

One of the huge, carnivorous dinosaurs could also be the largest specimen ever found.

Jack Horner, head of palaeontology at the Museum of the Rockies in Montana, US, described his team's finds as very unusual.

"On average, a T. rex is discovered once every 10 years," he told BBC News Online. "To find five in one summer in one area is very surprising."

Only 20 confirmed T. rex skeletons have been uncovered to date.

Horner, who acted as adviser to Steven Spielberg on the Jurassic Park films, is not willing to be drawn into immediate conclusions about the scientific significance of the discoveries.

Dinosaur evolution

But he concedes that it might mean the huge beasts were more common than previously believed.

The remains were found between June and September this year in the Fort Peck Reservoir area of Hell Creek, Montana. The area is a famous dinosaur hunting ground.

It has rocks that cross what is known as the K-T boundary, the layer where dinosaurs vanish from the geological record about 65 million years ago.

Horner and his team are involved in a five-year survey of the dinosaurs, mammals, invertebrates and fossil plants found in the region.

But they deliberately set out to look for creatures that lived long before the mass extinction - well below the K-T boundary.

Largest ever

"Most people have been interested in the extinction of dinosaurs, but I'm more interested in how they lived and evolved," he said.

Most of the Tyrannosaurus remains have not yet been fully uncovered. Parts of three skeletons and most of a fourth have been removed so far. The rest will be extracted next summer.

There is great excitement about one of the specimens in particular. This was discovered by Horner's wife, Celeste, in July.

The skeleton is only partially intact, but the jaw and a few cervical ribs removed late in the digging season seem to indicate that C-rex (as it has been dubbed) could be the largest T. rex ever found - bigger even than Sue, which drew huge crowds to the Field Museum in Chicago when it was put on full public display for the first time in May.

Dinos Not Cold-Blooded


Sept. 14, 2000 - AP

Scientists have argued for years whether dinosaurs were warm-blooded, like birds and mammals, or relied on the sun for warmth, as do cold-blooded reptiles. Lack of direct evidence, such as well-preserved organs, makes it a difficult question to answer.

However, geochemist Henry Fricke has found another way to tackle the problem; he studied the oxygen chemistry of fossilized dinosaur and crocodile teeth. Fricke discovered that the body temperature of meat-eating dinosaurs appeared warmer than cold-blooded crocodiles.

"The biggest impact this might have involves figuring out where dinosaurs fit evolutionarily in relationship to birds and reptiles," he said.

Using oxygen chemistry also provides a new line of evidence in the warm-blooded vs. cold-blooded debate. Fricke, now at Colorado College, performed the work while at the Carnegie Institute of Washington. He and co-author Raymond Rogers of Macalester College present their results in this month's issue of the journal Geology.

Analyzing oxygen chemistry is a popular method for evaluating ancient climates and fossils, but Fricke is the first to try the method on dinosaur teeth.

Oxygen atoms can have three different masses, known as isotopes. Scientists know that rainwater at higher latitudes contains more lighter oxygen isotopes than rainwater at lower latitudes.

Previous studies have shown that rainwater's isotope ratio affects the ratio recorded in tooth enamel, since animals drink rainwater. But a cooler body temperature skewers the ratio.

Fricke and Rogers studied 75-million-year-old teeth from crocodiles and three dinosaur species -- Albertasaurus, Majungatholus and Saurornitholestes -- that lived in a wide range of latitudes.

Fricke found that overall, the teeth of all the species studied reflected the rainwater ratio of the latitude. But he was surprised to find the crocodile teeth had slightly lower levels of lighter isotopes than the dinosaurs.

Body temperature is why, says Fricke.

This indicates the dinosaurs may have been internally regulating their body temperature, like warm-blooded mammals, he says.

Out of Africa

Tracks suggest Italy was not an island

August 22, 2000 - BBC

Fossil tracks found in Southern Italy suggest the Italian peninsular was connected to Northern Africa during the reign of the dinosaurs.

A hundred and thirty million years ago a group of dinosaurs walked across a muddy plain, leaving a trail of sixty massive footprints behind them.

The tracks solidified into rock - and have just been uncovered by a team of geologists from the University of Ferrara in Italy.

Some of the footprints have been identified as belonging to an Iguanadon, a nine metre long, five-tonne dinosaur.

The herbivorous creature is similar to dinosaurs that lived in North Africa - and this suggests that Southern Italy was connected to Africa a hundred and thirty million years ago.

Geological evidence supports the idea that Italy and north Africa are made from the same rocks - but up to now it was thought that the Italy of today was just a group of islands off the African coast.

But giant dinosaurs like the Iguanadon could not have survived on small islands - so the footprints are strong evidence that Italy was part of continental Africa.

T. Rex takes centre stage

Sue and Sue: Hendrickson unearthed the dino in South Dakota

May 17, 2000 - BBC

The monster specimen known as Sue, after the fossil hunter Sue Hendrickson who discovered it, takes centre stage at Chicago's Field Museum after extensive preparation.

The dinosaur, which was unearthed in South Dakota's Black Hills in 1990, cost the natural history museum $8.36m at an auction that had been delayed for years by a drawn-out legal battle that ended with Hendrickson's partner in jail.

To cover the cost of the 67-million-year-old carnivore, the Field has taken on two major corporate partners in McDonald's and Disney.

The two organisations share exclusive rights to casts of Sue's bones; the museum keeps the real ones, which have been put up in its main hall.

Sue's one tonne skull, too heavy to be mounted with the rest of the skeleton, will be displayed in a case nearby. A lightweight cast will replace it on the skeleton.

Longest tooth

"People, in all the alternatives they have in computer games, shopping, the internet... love real things,'' Field President John McCarter said.

Sue - palaeontologists are not sure whether this dino is male or female - is 12.5 metres long (41 feet) and about four metres (13 feet) tall at the hip.

Sue Hendrickson watches restorers as they make a cast of the lower jaw of the dinosaur

At 85-90% complete, Sue is the most comprehensive T. rex ever found, and has one of the only two T. rex arms ever to be discovered.

Sue can boast the longest tooth yet found for a T. rex, measuring 30 centimetres from root to tip.

Fewer than 25 such carnivores have ever been unearthed. "You can't do anything with a fossil till you know what's there," says palaeontologist Chris Brochu, a research associate at the Field and the lead researcher on the dino. Some details of Sue's skeleton may reveal more extraordinary events in her life. A number of her bones show pathologies; there are holes, scars, masses, and even two misshapen teeth.

A number of the wounds were at first thought to be bite marks and battle scars. But Chris Brochu, after consulting with a palaeopathologist (a scientist who studies disease and injury in fossils and other remains), now thinks most of the lesions were probably caused by infections.

"What's interesting is that Sue didn't die from any of these wounds. They all show extensive healing, a sign of good health. At this point it looks like Sue lived a good, long life - and then she just died."

Part of prehistoric mastodon unearthed in Nevada

May 7, 2000 - Nando

Time and archaeological graverobbers are finally taking their toll on a prehistoric gem that has withstood millions of years of geologic upheaval.

Within a month of the chance discovery of the fossilized remains of a mastodon in late March and before excavation could begin, looters had moved in, taking some artifacts and damaging others.

Tom Lugaski, director of the W.M. Keck Museum at the University of Nevada, Reno, is optimistic they left the best stuff behind.

"It's like Christmas time with all these packages around here," he said as the dig got under way at the end of April.

To his right, a shallow pile of crushed ribs bore testimony to the work of vandals. But to his left, some 20 scientists, students and volunteers picked and chipped around the partially exposed leg of the creature, which roamed what was then a marshy western Nevada some 3 million to 3.5 million years ago.

The surprising find was made at the end of March by two teen-agers who were riding motorcycles in the steep and rocky canyons of the Pine Nut Mountains.

Derek Prosser and Dustin Turner not only recognized the object sticking out of the rock as a large bone, but reported their find to the federal Bureau of Land Management.

Prosser, 18, said he had seen enough bones to know these weren't just an outcropping of rock, especially when he spotted the crystallized marrow.

"After taking a close look, it kind of shocked me. I knew it was something very unusual," he said.

The boys took some specimens to the bureau.

"They did everything exactly right. We're lucky they found the bones and even luckier they reported it," the bureau's historical archaeologist Gary Bowyer said. The find is on BLM-administered land.

Despite the rugged remoteness of the site, word leaked out of its whereabouts and there have been signs of non-scientific exploration, Bowyer said. That put pressure on the experts to interrupt their Easter weekend before there's any lasting damage.

"This is an emergency excavation," he said.

Using tools ranging from pressure bars to hammers and chisels to soft brushes, workers hunkered down in a pit about 10 feet in diameter to remove the fairly soft sandstone from around the buried bone.

"We have the front leg, from the shoulder down to the foot," Lugaski said. "At this point, we don't know if there is any more that we can see. It would be nice if we could find the whole thing, but they die and disintegrate."

He said the foreleg alone is a rich reward.

"Most often, you'll get a piece of tooth, a piece of leg bone. A whole front leg starts to get fairly rare. What's important is they're finding more and more pieces of it."

A fist-sized chunk of skull and the fragments of rib bones leave Lugaski optimistic that more work will unearth discoveries that range beyond just the leg.

"Hopefully there'll be some more out there. It could be scattered over hundreds of feet. You never know," Lugaski said.

The dig is on hold until workers remove dirt and rocks the centuries have deposited in the rocky canyon uphill from the excavation.

The paleontologically rich area already has yielded remains of camels, horses and extinct bears, which help establish the date of the American mastodon as being at the upper end of the species' reign in North America. They first appeared about 3.75 million years ago and abruptly disappeared 10,000 years ago at the beginning of the Ice Age.

A youngster had little trouble gathering ancient non-mastodon teeth lying on the steep hillside above the dig to turn over to the researchers. Walking off with archaeological trophies can bring a stiff fine.

The site now almost exactly one mile above sea level originally was some 700 feet lower and was much wetter since the Sierra were still forming and Pacific storms could easily cross into the valley, according to Pat Cashman, an associate professor of geology at UNR.

The climate encouraged the growth of shrubs and small trees in great enough abundance to keep the elephant-like animals well fed.

"They'd clear off this whole hillside in no time today," Cashman said, gesturing toward the spotty growth of juniper and sagebrush.

Mastodons were smaller than their towering relatives, the mammoths, and were squatter and longer than modern elephants, averaging 6 feet to 10 feet at the shoulder and about 15 feet from the root of the tusks to the start of their tail. They were covered by a coarse, reddish-brown hair.

The age of this mastodon makes it a rare find but also makes radioactive carbon dating impossible since that is accurate only to about 500,000 years, according to UNR graduate student Tom Mantean. Other dating methods and fossilized material around the excavation will make more accurate dating possible as the remains are studied in greater detail at the university.

Monstrous Dinosaur Found In Texas

January 7, 2000 - AP

Texas paleontologists have discovered a hulking giant of a dinosaur with a neck more than 30 feet long and a vertebra weighing up to 1,200 pounds. The researchers say the fossil is probably by far the largest dinosaur ever found in the Lone Star State.

"This thing is just bloody enormous," says Homer Montgomery, a paleontologist at the University of Texas at Dallas, who along with his students found the creature in a wilderness area of South Texas� Big Bend National Park last fall.

Montgomery and his team were able to haul out the two smallest cervical, or neck, vertebrae -- one weighing 367 pounds and the other 470 pounds -- by hand before leaving the dig for the winter.

Most of the creature remains in the ground near an established bone bed full of juvenile Alamosaurus remains dating to the Late Cretaceous, only a few million years before dinosaurs died out.

Alamosaurus, part of a dinosaur family known as titanosaurs, was the last of the long-necked dinosaurs called sauropods to roam North America, but is so far known only from scattered and broken remains. The 23-foot length of the new dinosaur�s neck may represent the largest intact section of the largest Alamosaurus ever found.

But its monstrous dimensions also suggest that it could be an entirely new species that exceeds the accepted 70-foot length of Alamosaurus adults by some 30 feet, Montgomery says.

"We know so little about this dinosaur that any find is important and something this large is doubly so," says Tony Fiorillo, a paleontologist at the Dallas Museum of Natural History who has also worked in Big Bend.

Montgomery plans to return to the remote desert site in February to remove more of the 10 vertebrae his team has already exposed and to excavate ribs and other bones protruding from the ground.

As the largest of the vertebrae measures more than five feet across and weighs about 1,200 pounds, a helicopter may eventually have to airlift the ancient creature out of the wilderness, says National Park Service geologist Don Corrick.