Giants of history

The Greatest Show Unearthed' presents dinosaurs in a new light

June 14 1993

Giants of history

The Greatest Show Unearthed' presents dinosaurs in a new light

June 14 1993

Giants of history

The Greatest Show Unearthed' presents dinosaurs in a new light

The enormous long-necked animal, measuring 90 feet from nose to tail-tip and weighing more than 25 tons, cut an imposing figure as it grazed on the ferns and rushes growing along the banks of a river on the Asian floodplain.

About 50 years old, and just reaching sexual maturity, the dinosaur known as Mamenchisaurus might have lived to a venerable 200 years—if disaster hadn’t struck. Attacked by a smaller, predatory dinosaur called Sinraptor, which prowled on two legs and came equipped with fearsome teeth and claws, the Mamenchisaurus fled towards the river and in its panic tumbled off a cliff. While the predator

watched in frustration, the drowning giant was swept away by the river current. Downstream, the animal’s corpse washed ashore. As the body decomposed, it broke up, leaving the head and neck on shore, while the rest of the carcass floated on. Later, the flooding river coated the dinosaur’s remains with layers of sediment that, over time, turned to rock, entombing the Mamenchisaurus’s bones. Time passed.

About 150 million years later, in July, 1987, members of a ChineseCanadian fossil-hunting expedition in the forbidding wastes of the Gobi Desert spotted part of a five-foot-long bone projecting from a hillside. It was part of the neck of that Mamenchisaurus. As team members excavated its remains, I they pieced together the above “ scenario as a likely one for the

creature’s death. Now, the dinosaur’s neck and a segment of its head, reclaimed from the Gobi’s red sandstone, form part of a large and impressive dinosaur show that opened in Edmonton on May 14 and moves to Toronto’s Ontario Place in August. The show, which is scheduled to travel on to Osaka, Japan, early in 1994, is punningly entitled The Greatest Show Unearthed. It is also billed as the largest travelling science exhibition ever mounted.

With more than 80 fossils on display, the core of the show is formed by the remains of 30 dinosaurs—including 11 previously unknown species—most of them discovered by the Chinese-Canadian team during five years of bone-hunting in the Gobi Desert, Western Canada and in the Canadian Arctic between 1986 and 1990. The team, which braved temper-

atures of 35° C and fierce sandstorms in the desert, was led by three eminent paleontologists: Dale Russell, of the Canadian Museum of Nature in Ottawa; Philip Currie, head of dinosaur research at the Royal Tyrrell Museum of Paleontology in Drumheller, Alta.; and Dong Zhiming, of Beijing’s Institute of Vertebrate Paleontology and Paleoanthropology. As a result of their work, about 15 tons of Gobi Desert fossils were shipped back to Canada for study and exhibition (the fossils remain Chinese property and will eventually be returned to Beijing). “We collected so much material,” said the 44-year-old Currie, a lanky native of Oakville, Ont.

“We could spend the next 10 years preparing specimens.”

The expedition was the first by Western fossil-hunters in the Chinese portion of the Gobi Desert in northwestern China since 1930, and the results excited experts in the field. “It was a very significant expedition,” said Peter Dodson, a University of Pennsylvania anatomist who specializes in dinosaurs. “They found some awfully interesting things.”

The discoveries of the Chinese-Canadian expedition enlarged scientists’ knowledge of the creatures that dominated the planet for 160 million years, before vanishing in a mass extinction 65 million years ago. The major finds included the neck and jawbone of the Mamenchisaurus, most of the skeleton of a Pi-ton Sinraptor, a group of young armored Ankylosaurs and the remains of a Sinomithoides, a clawed, chicken-sized dinosaur with an impressively large brain.

The expedition also shed new light on dinosaur habits and produced evidence that reinforced the growing trend among paleontologists to reject the old image of dinosaurs as being cold-blooded, slow-witted reptiles. Most scientists now say that many dinosaurs may have been warm-blooded, relatively nimble and more intelligent than was previously believed.

As well, the similarity between some Chinese dinosaurs and fossils found in southern Alberta could mean that Asian dinosaurs may have trekked across land bridges from Asia to settle in North America about 150 million years ago. Some dinosaurs may have gone the other way. Dinosaurs may have also migrated seasonally from southern Alberta to spend their summers in the Canadian Arctic, which then had a mild, temperate climate. “We have evidence of dinosaur herds that must have overtaxed the amount of food in a given area,” says Russell, 55. “So these large assemblies, on the order of thousands of dinosaurs, must have moved.”

The Greatest Show Unearthed, which is being staged under a tent covering six acres of exhibition space, reflects the new thinking about dinosaurs. It also unabashedly mixes science with Disneyland-style hoopla, audiovisual aids and gimmicks aimed at beguiling families—and especially children. Visitors to the show enter along a street of false-fronted stores devoted to popular images of dinosaurs: one shop is stuffed with dinosaur toys, while others show dinosaur movies from the past, including 1975’s The Land That Time Forgot. Then, passing between columns that hint at the formal atmosphere of traditional museums, visitors confront a snarling jet-black skeleton of a Tyrannosaurus rex. The bones of the flesheating “tyrant lizard king” were blackened by naturally occurring manganese as they lay beneath the earth in the Crowsnest Pass on what is now the Rocky Mountains border between southern Alberta and British Columbia.

Another section of the show offers a recreation of living conditions among the Chinese-Canadian team members in the Gobi Desert. Inside a tent are sleeping bags, a half-finished bottle of whisky, bowls of rice and chopsticks. In an exhibition area called the Boneworks, reallife technicians work on fossils, sifting through rock remnants in search of bone or tooth fragments and preparing plaster and polyester casts. Among the Gobi fossils on display are the neck and jaw of the Mamenchisaurus, the largest dinosaur ever found in Asia, and the skeleton of the birdlike Sinomithoides. Exhibition-goers can press a button to hear what the voice of the Hypacrosaurus, a duck-billed dinosaur found in Alberta, may have been like. “It might have sounded like that,” said Jack Wojcicki, the show’s program assistant, of the nasal cry that he and other scientists decided on after studying the dinosaur’s anatomy.

The exhibit, and the rapt attention of its visitors, demonstrates the remarkable ability that dinosaurs have had to capture the human imagination ever since the 19th century. It was then that growing interest in European fossil discoveries prompted British naturalist Richard Owen to coin the term dinosaur, from the Greek words for “terrible lizard.” The Victorian-era dinosaur craze crossed the Atlantic, sending American and Canadian fossil hunters across the continent in search of remains, which they found in profusion in Montana, Wyoming, Utah and other states—and in the Badlands of southern Alberta. In 1884, a Torontonian named Joseph Tyrrell was exploring a canyon in Alberta’s Red Deer River Valley when, as he later wrote, he spotted “this skull leering at me, sticking right out of the rock. It gave me á fright.” It was the first dinosaur skull ever found in Canada.

The origins of the Gobi Desert expedition go back to a conversation in 1982 between Currie, then an Edmontonbased paleontologist with the Alberta Provincial Museum, and Brian Noble, a young Alberta communications consultant. Noble was helping to lay the groundwork for the Tyrrell museum, which opened in 1985 as the scientific centre for dinosaur research in Alberta. As a boy, Currie had been captivated by accounts of the adventures of Roy Chapman Andrews, a swashbuckling American paleontologist who was the model for the fictional character in the Indiana Jones movies. Andrews hunted dinosaur skeletons in the Gobi Desert during the 1920s, and when Noble asked Currie where he would most like to hunt for fossils, Currie unhesitatingly replied: “The Gobi.”

Armed with an $8,000 Canada Council grant, Noble launched a feasibility study to determine how an expedition could be mounted, and in 1984 set up the Edmonton-based, nonprofit Ex Terra Foundation to organize it. Eventually, Canadian negotiators worked out details of the joint expedition with Chinese officials.

During the summer of 1986, the joint dinosaur hunt was launched. Using part of a fleet of eight Cherokee Jeeps donated by the Torontobased Donner Foundation of Canada, Russell, Currie and Dong carried out a three-week reconnaissance of Gobi Desert dinosaur sites. Later that summer, Currie and Russell took Chinese scientists on a tour of fossil-rich locations in Alberta and the United States, and on a

fruitless dinosaur-hunting expedition to Axel Heiberg Island in the Canadian Arctic. Back in the Gobi the following year, the Chinese-Canadian team began searching for fossils near the town of Jiangjunmiao in a barren, windswept region known as the Junggar Basin, 2,500 km west of Beijing. They got lucky almost at once, locating the remains of the Mamenchisaurus,

the partial skeleton of a Sinraptor, and parts of dozens of other prehistoric creatures.

The list of discoveries grew as the Chinese-Canadian team, totalling as many as 50 scientists, technicians and support personnel at the peak of its efforts, ranged across the largely uninhabited region. Sometimes the explorers split up. Working in the Alashan desert, near the Mongolian border in 1988, Russell found the remains of a strange, sloth-like dinosaur tentatively dubbed Alxasaurus. Farther to the east, Currie made a spectacular discovery near the town of Bayan Mandahu. He located the skeletal remains of 12 young Ankylosaurs.

Project Dinosaur’s Gobi Desert operations were abruptly cut short in June, 1989. Following Beijing’s brutal repression of pro-democracy

demonstrators in Tiananmen Square, Ottawa ordered the Canadians to leave China. They returned in 1990 for another season, but made disappointingly few discoveries. As well, a second expedition in 1989 into the Canadian Arctic, where traces of dinosaur life have been found in the past, failed to produce any important fossils. Meanwhile, Chinese scientists on reciprocal visits to Canada played a part in several intriguing discoveries. In 1986, for example, a Chinese technician found the well-preserved braincase of a Troodon, another small, birdlike dinosaur with a large brain.

That discovery was important, because the exact relationship between dinosaurs and birds is a hot topic in paleontology. According to Currie, nearly all paleontologists now believe that today’s birds are the descendants of dinosaurs. But some dinosaur experts, including Russell, argue that in the later stages of their evolution many dinosaurs were acquiring, or “mimicking,” some birdlike characteristics, without becoming birds. In evolutionary terms, says Russell, the animals were becoming smaller, more efficient and better equipped to survive.

Why—in spite of that—the dinosaurs vanished 65 million years ago was a question that puzzled experts for years. Now, many dinosaur experts agree that a comet crashing into the earth’s surface may have doomed the dinosaurs by creating fire storms, followed by cold temperatures and heavy acid rain

that destroyed vegetation and starved the dinosaurs. During the 1970s, American geologist Walter Alvarez found that a thin layer of clay in geological formations dating from the time at which dinosaurs vanished contained high levels of the element iridium. Because iridium is found in only tiny amounts in the earth’s crust, the clay layer pointed to fallout from an asteroid or comet colliding with the earth.

A Canadian scientist played a key role in determining exactly where a comet probably struck. Reasoning that the dust-like “ejecta,” or debris, created by the comet’s impact would be thickest in the area where the comet struck, Alan Hildebrand, now a research scientist with the Geological Survey of Canada in Ottawa, found evidence that pointed to the Caribbean region. Then in 1991, Hildebrand and six American and Mexican colleagues published a paper pointing to an area near the town of Chicxulub in the northern part of Mexico’s Yucatán Peninsula. Since then, scientific studies in the Chicxulub area have produced evidence supporting Hildebrand’s contention that it was there that the comet struck.

The dinosaurs are gone, but as the crowds thronging The Greatest Show Unearthed attest, they are far from forgotten. In Russell’s case, the fascination of the ancient animals is that they “help me to

¿¡T understand the continuity of life, because in our ability to think

and our ability to work we imitate the success story that got the dinosaurs as far as they went.” And happily for dinosaur hunters today and in the future, many more of the mighty creatures are, like the Mamenchisaurus, bound to be locked inside the earth’s ancient crust, waiting to be discovered.