Did the real Tyrannosaurus rex resemble the one in Jurassic Park?




Scientists know much more about Tyrannosaurus rex than they did 20 years ago.

No dinosaur is more cherished than Tyrannosaurus rex. The Cretaceous king of the tyrants epitomizes the size, ferocity, and bizarre nature of dinosaurs that continues to enchant us. We're so smitten with T. rex that we are continually bringing the dinosaur back to life through art and film.

Perhaps no restoration of the great carnivore has been as influential or celebrated as the genetically engineered tyrant that terrorizes Jurassic Park, which is being re-released in 3D today. Revived through computerized special effects and puppetry, the film's T. rex is a muscular, agile predator far more imposing than the tottering, tail-dragging representations that had appeared on film before. And in the 20 years since Jurassic Park debuted, as knowledge about T. rex has increased, the dinosaur has become even scarier still.

"It's hard to pick a single coolest discovery about Tyrannosaurus rex itself over the last 20 years," says University of Maryland tyrannosaur expert Thomas R. Holtz, Jr. Paleontologists have started to understand how drastically T. rex changed as it grew into an adult and to make sense of the neurological "CPU [central processing unit] and sensors of the killing machine" that made T. rex so deadly, says Holtz.

Beware the Maw

Of all the dinosaur's traits, the maw of T. rex has probably inspired the most nightmares—and much of the cutting-edge science. The predator's deep, reinforced skull was set with an array of thick, serrated teeth that evolved to pierce and cut simultaneously.

Jurassic Park's T. rex put that impressive array of dental cutlery to work on the hapless lawyer Donald Gennaro and a fleeing Gallimimus, as well as a pair of raptors at the film's climax, but the predator had an even more formidable bite than the movie portrayed. 

Last year, researchers Karl Bates and Peter Falkingham announced that an adult T. rex had a bite force of almost 12,800 pounds—the most powerful estimated bite force of any terrestrial predator. Considering the damage a full-force T. rex bite would have inflicted, Jurassic Park's tyrannosaur looks as if it's being downright gentle with its prey.

 


Jurassic Park imagined how T. rex used its weaponry, but there is actual evidence of T. rex biting techniques in the fossil record. After T. rex made a kill or found a carcass to scavenge, it could be a delicate feeder. As Denver Fowler and colleagues presented at the annual Society of Vertebrate Paleontology meeting last fall, toothmarks on Triceratops skulls hint that T. rex had a step-by-step method of decapitating Triceratops.

Yet the destructive power of T. rex wasn't isolated in its jaws. The dinosaur's neck muscles played a major role in the carnivore's ability to kill and consume prey. In their 2007 study of T. rex feeding mechanics, Eric Snively and Anthony Russell found that the dinosaur's neck muscles were so strong that the tyrannosaur could have thrown a 110-pound chunk of meat 15 feet into the air and caught it again—a frightening ability known as "inertial feeding." Rather than shake the movie's lawyer from side to side like a dog, a real T. rex might have tossed Gennaro into the air with a flick of its neck, catching him as he fell back toward all those teeth.

Deadly Bite

T. rex didn't use its teeth and jaws just to pierce the flesh and crush the bones of prey. Tyrannosaurs also bit each other. Healed wounds on the skulls of tyrannosaurs—such as the teenage T. rex nicknamed Jane—show that these theropods tussled by biting each other on the face. (Arm wrestling wasn't an alternative, apparently, though T. rex's small arms were heavily muscled and strong for their size.)

This bit of prehistoric behavior might explain why some of the largest carnivores of all time were ultimately killed by much smaller organisms. The lower jaws of many T. rex are pockmarked with smooth-sided holes. Some researchers thought that these were bite wounds from fatal attacks by rivals, but in 2009 Ewan Wolff and colleagues proposed that these injuries were created by tiny microorganisms that cause the same kind of damage in birds of prey. The protozoans infest the upper digestive tract of the birds, creating ulcers and lesions before eventually boring into the bone. The feathery raptors catch the little hitchhikers by eating infested pigeons.

Perhaps T. rex picked up similar microorganisms through dinosaur-to-dinosaur transmission. Face-biting would be a direct way for the harmful microorganisms to jump from one T. rex to another. Thanks to tooth-damaged bones, researchers also know that tyrannosaurs cannibalized each other and could have picked up parasites that way. Regardless of the pathway, it would seem that the bite of a tyrannosaur wasn't deadly just to prey, but to other tyrannosaurs, too.

Fearsome but Not Fast ... and Feathered?

Even when paleontologists downgrade the abilities of T. rex, the dinosaur still seems scary. One of the most famous scenes in Jurassic Park is the Jeep chase, with an angry T. rex almost making a snack of the smarmy chaos theorist Ian Malcolm. Could T. rex really run fast enough to keep up with a speeding car? The work of researcher John Hutchinson and colleagues suggests not.

For one thing, the movie's T. rex wasn't actually moving very fast. The escaping Jeep looks like it's moving 40 miles per hour or more, as Hutchinson explains on his lab's website, but the dinosaur's movement—it always has one foot on the ground—indicates that the T. rex is moving only about 10-15 miles per hour. This fits what the dinosaur's skeleton suggests about its speed. By Hutchinson's calculations, T. rex walked about 6 miles per hour and ran about 15-25 miles per hour. A top speed of 25 miles per hour may seem meager, but the only humans able to exceed it are highly trained Olympic athletes. If you were unfortunate enough to be caught off guard by a T. rex out in the open, you'd stand no chance of outrunning the carnivore.

Picturing the tyrant wearing feathers—a likelihood since two other tyrannosaurs have been found with coats of dinofuzz—may change its image a bit. As researchers have filled in the deep history of the dinosaur, they have determined that the earliest Jurassic tyrannosaurs were "small, fast, and fuzzy ... not much at all like the giant T. rex of Jurassic Park," says Holtz.

But to date, Jurassic Park's T. rex is the best committed to film. "I think the movie pretty much nailed it," Hutchinson says, "as much as 'it' can be nailed, given the uncertainties." Holtz agrees: "The movie gave Tyrannosaurus a seriously high but justifiable level of awesome," he says, as the dinosaur's behaviors shown throughout the film series include "parental care, family hunting, puncture-and-pull feeding, chasing prey with a fast walk." If anything, what was on screen was "not too different from the Tyrannosaurus behaviors we would interpret today." (See related story: Writer Revisits Teenage Love of Jurassic Park)

Sadly, we're never going to get to witness a living T. rex chase after dinosaurian prey—or even after us—to know for sure how closely Jurassic Park's informed speculation matches reality. The movie's intricate puppets and special effects dinosaurs may be the closest we ever come to seeing a tyrannosaur walk the Earth again. When you revisit Jurassic Park and watch T. rex howl its terrifying cry of freedom as it stomps out into the stormy night, you will be experiencing the best cinematic tribute to one of the most awesome carnivores to have ever evolved.

Fossils uncover ‘weird’ chimp-human creature called Australopithecus sediba






She walked with a knock-kneed gait, with a heel like a chimp but the upright posture of a human, and she may provide the most complete evidence yet of early man’s closest ancestor, scientists said Thursday.

Two-million-year-old Australopithecus sediba’s awkward strut would eventually send a modern man begging for a knee or hip replacement, but scientists are stunned at how evolution equipped her for both climbing trees and walking.

The latest research on an unprecedented set of fossil bones from South Africa reveal an ancient creature with long arms and primitive shoulders like an ape, but legs that could straighten, dexterous hands and a human-like thumb for precision grip.

“Just a weird, weird combination,” said Jeremy DeSilva of Boston University, lead author of one of the six articles in the US journal Science that describe the most complete set of bones ever found for an early hominid.

The latest findings offer more distinctions from the famed hominid Lucy, who was discovered in 1974 and whose species Australopithecus afarensis roamed eastern Africa 3.2 million years ago, experts said.

“What these papers suggest is that sediba probably doesn’t come from the East African species that Lucy comes from,” said Lee Berger, who in 2008 discovered the fossil site of Malapa, north of Johannesburg, where excavations are ongoing.



Au. sediba walked in a way never before seen by researchers, with a rib cage and spine that is “very ape-like at the top and human-like at the bottom,” said Berger, a professor at the University of the Witwatersrand.

The bones of five individuals have provided some stunning firsts — the first-ever kneecap, the most well-preserved upper limb, and a complete set of foot, leg and hip pieces from an adult female that have allowed her gait to be decoded.

DeSilva said the adult female Au. sediba was a hyper-pronator, meaning her foot was tilted inward.

Without a strong heel base like humans have, she would have landed on the outside of her foot, causing her shin, knee and thigh bones to twist inwards and she strode.

Sound painful? To us, it might be. But maybe not to this female, referred to by researchers as MH2.

“They have the anatomy that allows them to do this and to do it well,” DeSilva told AFP.

The kneecap has a large ridge that keeps it in place, and likely kept MH2 and her cohorts alive in a dangerous world, he said.

Experts believe the creatures are so well preserved because they died after falling into a sinkhole. So far they have uncovered remains of an adult female, a juvenile male, a toddler, an infant and another adult.

“This could very well be a family group,” said DeSilva. “I have never seen fossils this well preserved. It’s unreal. They are stunning.”

Articles detailing Au. sediba’s hands and teeth — signaling they ate a diet of fruit, leaves and bark — have been previously published.

Other studies in the current issue of Science offer a more detailed glimpse at their jaws, teeth, rib cage, upper arms and spine.

The work is part of an ongoing project by international scientists from the Evolutionary Studies Institute at the University of the Witwatersrand and 15 other global institutions.

“We have this incredibly exciting look, maybe the best look at any early hominid species that had ever happened,” said Berger.

“It may be that it should be considered the best candidate ancestor for early members of the genus homo.”

Zeresenay Alemseged, head of the anthropology department at the California Academy of Sciences, described the work as a “fantastic discovery.”

“What this really tells us is that early hominin evolution was more diverse at this time than we thought.”

However, he questioned the claim that this may be the closest ancestor of modern man, noting that other fossils have shown clues of the genus homo long before Au. sediba’s time, 2.33 million years ago.

“The link to homo is not well established. The torso, the clavicle, the foot have many primitive characteristics,” he added.

Mysterious Stone Structure Discovered Beneath Sea of Galilee





A giant "monumental" stone structure discovered beneath the waters of the Sea of Galilee in Israel has archaeologists puzzled as to its purpose and even how long ago it was built.

The mysterious structure is cone shaped, made of "unhewn basalt cobbles and boulders," and weighs an estimated 60,000 tons the researchers said. That makes it heavier than most modern-day warships.

Rising nearly 32 feet (10 meters) high, it has a diameter of about 230 feet (70 meters). To put that in perspective, the outer stone circle of Stonehenge has a diameter just half that with its tallest stones not reaching that height.

It appears to be a giant cairn, rocks piled on top of each other. Structures like this are known from elsewhere in the world and are sometimes used to mark burials. Researchers do not know if the newly discovered structure was used for this purpose.

The structure was first detected in the summer of 2003 during a sonar survey of the southwest portion of the sea. Divers have since been down to investigate, they write in the latest issue of the International Journal of Nautical Archaeology.

"Close inspection by scuba diving revealed that the structure is made of basalt boulders up to 1 m (3.2 feet) long with no apparent construction pattern," the researchers write in their journal article. "The boulders have natural faces with no signs of cutting or chiselling. Similarly, we did not find any sign of arrangement or walls that delineate this structure." [See Photos of the Mysterious Sea of Galilee Structure]

They say it is definitely human-made and probably was built on land, only later to be covered by the Sea of Galilee as the water level rose. "The shape and composition of the submerged structure does not resemble any natural feature. We therefore conclude that it is man-made and might be termed a cairn," the researchers write.

More than 4,000 years old?

Underwater archaeological excavation is needed so scientists can find associated artifacts and determine the structure's date and purpose, the researchers said.

Researcher Yitzhak Paz, of the Israel Antiquities Authority and Ben-Gurion University, believes it could date back more than 4,000 years. "The more logical possibility is that it belongs to the third millennium B.C., because there are other megalithic phenomena [from that time] that are found close by," Paz told LiveScience in an interview, noting that those sites are associated with fortified settlements.

The researchers list several examples of megalithic structures found close to the Sea of Galilee that are more than 4,000 years-old. One example is the monumental site of Khirbet Beteiha, located some 19 miles (30 kilometers) north-east of the submerged stone structure, the researchers write. It "comprises three concentric stone circles, the largest of which is 56 m [184 feet] in diameter." [Gallery: Aerial Photos Reveal Mysterious Stone Structures]

An ancient city

If the third-millennium B.C. date idea proves correct it would put the structure about a mile to the north of a city that researchers call "Bet Yerah" or "Khirbet Kerak."

During the third millennium B.C. the city was one of the biggest sites in the region, Paz said. "It's the most powerful and fortified town in this region and, as a matter of fact, in the whole of Israel."

Archaeologist Raphael Greenberg describes it in a chapter of the book "Daily Life, Materiality, and Complexity in Early Urban Communities of the Southern Levant" (Eisenbrauns, 2011) as being a heavily fortified 74-acre (30 hectares) site with up to 5,000 inhabitants.

With paved streets and towering defenses its people were clearly well organized. "They also indicate the existence of some kind of municipal authority able to maintain public structures ..." Greenberg writes.

The research team says that, like the leaders of Bet Yerah, whoever built the newly discovered Sea of Galilee structure needed sophisticated organization and planning skills to construct it. The "effort invested in such an enterprise is indicative of a complex, well-organized society, with planning skills and economic ability," they write in their journal paper.

Paz added that "in order to build such a structure a lot of working hours were required" in an organized community effort.

Future exploration

Paz said that he hopes soon that an underwater archaeological expedition will set out to excavate the structure. They can search for artifacts and try to determine its date with certainty.

He said that the Israel Antiquities Authority has a research branch capable of excavating it. "We will try to do it in the near future, I hope, but it depends on a lot of factors."