The biggest of the big

The Morning Call: The biggest of the big. 'The World's Largest Dinosaurs' exhibit in New York City reveals secrets for living large

"The World's Largest Dinosaurs," a new exhibit at New York City's American Museum of Natural History, digs deeper than fossil pits to take visitors beyond standard dinosaur skeletons and rock-studded fossils. It teaches fascinating new facts about how these tractor-trailer-size giants lived and thrived for 140 million years.

What dieter wouldn't envy a sauropod who had to eat 1,000 pounds of food daily, just to "beef up" by 10 to 12 pounds a day? Of course, there were downsides for these eating machines. As the exhibit explains, they needed to grow new teeth as often as once a month because eating so much wore their teeth down quickly. Apparently, they also farted (excuse me!) often because they released about 13 gallons of gas per day while processing their food.

Mamenchisaurus, a massive 18-year-old female dinosaur at the heart of the exhibit, stands 11 feet tall and 60 feet long and doesn't blush at all about such revealing facts.

Fleshed out to her life-sized full figure, she lights up to expose even more information about herself and other members of her plant-eating sauropod clan that also included the Apatosaurus (formerly known as the Brontosaurus). Although the average weight of the Mamenchisaurus was 12 tons, the biggest sauropod of all, the Argentinosaurus, tipped the scales at 90 tons. You'd have to pile 15 modern-day elephants on a scale to make his weight!

People are always fascinated by the world's large things, from the tallest buildings to the largest ball of twine, says museum president Ellen Futter. "These sauropods were the most super-sized creatures of all time and their size raises all kinds of questions about how and why they were so big and what they needed to live."

She adds, "We've moved beyond bones to biology. Scientists are learning more and more about what made these animals tick."

Their findings went into the creation of the Mamenchisaurus as well as into interactive parts of the exhibition, including hands-on and computer activities for kids and a re-creation of a dig site complete with fossils.

As you sit on one of the benches along the Mamenichisaurus' left side, take a minute to gaze from the tip of her face to the end of her tail. An amazing old girl, she lived 160 million years ago, in what is now China. She is depicted with a mouthful of plants, as she grazes her way to her required daily allowance of greenery.

Listen and you'll hear her breathing and her beating heart. Thanks to a video projection system, you'll see her sides move and learn more about her super-efficient respiratory system, with storage sacs that filled with fresh air and gave her twice the fresh air for every breath she took.

Then, check out the projections of her tummy. It functioned like a compost heap, with sausage-like projections that contained the fermenting plants she ate. Turning the plants into energy could take as long as two weeks.

Walk along the Mamenchisaurus' other side and you'll see the rough texture of her skin. Although the old girl lacks the Disney-like allure she'd get from singing, dancing, walking or talking, she still makes a big impression worthy of the footprints her family once cast upon the earth.

Beyond the life-size model there's a wealth of new information and audiovisuals that will increase your understanding of these giants. A multidisciplinary approach was used to develop the intriguing new information about the sauropods. Paleontologists were joined by biologists, botanists, animal nutritionists and engineers who used their expertise to draw conclusions about the dinosaurs' lives. New technology, including CT scans, has helped reveal even more, like the two gyroscope-style structures lodged inside a sauropod's skull that were its balance organs and embryos in dinosaur eggs.

"Finding out what kept the dinosaurs alive, how much they ate, how they grew and how they got blood from their heart to their brains at the end of such long necks were unapproachable questions a few years ago. Now we can shed light on their lives," said Michael Novacek, senior vice president and curator of the Division of Paleontology at the museum.

The exhibition begins by exploring how size affects just about everything an animal does, from eating and breathing to moving and reproducing, as well as how the sauropods got bigger and bigger over the 140 million years they roamed the earth. It explains that predators don't usually attack the largest animals of a group. So natural selection favored bigger animals and over time, the descendents of the larger animals kept getting bigger and bigger.

Another section explores teeth and eating, and explains how these huge plant-eaters tore off the tips of branches or stripped the leaves from them with rake-like teeth and swallowed them whole. One sign says, "Because they had to get as much down their gullets as possible, taking the time to chew would have been a fatal error."

The exhibit has 11 areas, including Head, Neck and Movement; Heart and Circulation; Lungs and Breathing; Stomach and Digestion; Eggs and Reproduction; How massive were sauropods?; What did sauropods look like?; How did sauropods behave? and How do paleontologists excavate fossils? They'll give you a much broader picture of all aspects of a dinosaur's life than you'd get by simply exploring the museum's other dinosaur-related halls of skeletons and fossils.

As you go, you'll discover features dinosaurs have in common with today's creatures, from the breathing system and egg-laying characteristics of birds to the light-but-long necks of giraffes and the digestive system of Galapagos turtles.

You'll gain new insights. Their big-enough brains that weighed in at less than half a pound (our brains weigh 48 ounces) gave them enough smarts to find food, herd their young and be the dominant plant eaters on earth for 140 million years. However, as an exhibit sign says, "That's not to say they were deep thinkers!"

These giants probably moved at speeds from 1 to 5 miles per hour.

What would it have been like to touch one? Their skin was dry and warm, and their scales were bumpy and knobby. Because they had no sweat glands, they didn't perspire.

You can touch dino teeth and skulls, calculate a dinosaur's size from its femur bone and see how much effort it took for a dinosaur's heart to circulate blood throughout its body. Just be sure you've eaten your Wheaties before you try to pump the hand-pump set to the correct pressure.

You'll encounter an eye-popping, bowl of greens that's taller than a person and as large as a whole group of people standing inside a large elevator. The contents of these mega-eaters' favorite salad? Botanists say it included ginkgo, ferns and conifers and the tough-but-nutritious horsetail plant.

After examining a range of eggs laid by living and extinct species, you'll realize dino eggs weren't as huge as you'd expect, with the largest ones weighing in at around 9 pounds. You can see and touch fossil eggs and examine eggshells' pores with a magnifier. At the end, kids can don goggles and use brushes and chisels to find fossils in a re-created dinosaur dig.

Dr. Steven Perry, a zoology professor at the University of Bonn in Germany, was one of the researchers involved in determining how these huge creatures breathed. On hand on press preview day, he lamented, "I'd love to be a kid now. In my youth, all we could do was look at the fossilized bones and skeletons and say, 'Wow.' Now, however, kids can ask questions that I asked and get answers."

Doctor Who,” the world’s longest-running science fiction television show, returns to the small screen on Saturday, April 23, with a bang—literally.

Los Angeles Times: Harley Garbani dies at 88; Fossil hunter unearthed significant dinosaur finds
A self-taught paleontologist and archaeologist with a longtime passion for hunting dinosaur bones, Harley Garbani found partial skulls of the youngest-known Tyrannosaurus rex and the youngest-known Triceratops.

By Dennis McLellan, Los Angeles Times

April 24, 2011
He was a onetime plumber who gained unexpected renown pursuing his lifelong avocation as a fossil hunter who discovered some of the world's most significant dinosaur fossils.

From Mexico to Montana, self-taught paleontologist and archaeologist Harley Garbani spent decades "prospecting for bones" in the badlands where bedrock is exposed. He also amassed one of the finest collections of Native American artifacts in Southern California.

His prime fossil finds are on display at the Natural History Museum of Los Angeles County, the University of California Museum of Paleontology in Berkeley and the Museum of the Rockies in Bozeman, Mont.

Garbani died Thursday of natural causes at his home in Hemet, said his wife, Mary. He was 88.

"He was a very passionate fossil hunter and someone who understood the scientific value of fossils," said Luis Chiappe, director of the Natural History Museum's Dinosaur Institute.

"He didn't have any academic training in the field, and he didn't do any research," Chiappe said. "He was primarily a field person, and he made some truly unique discoveries."

Those finds include the partial skulls of the youngest-known Tyrannosaurus rex and the youngest-known Triceratops, two iconic dinosaurs, which will be on display in the museum's new Dinosaur Hall when it opens July 16.

The skulls are among many of Garbani's fossil finds that have been displayed over the years at the L.A. County museum, which paid him to lead fossil-hunting expeditions to Montana in the 1960s.

While leading such a trip in 1966, Garbani found the skull, jawbone and other parts of a T. rex on the Engdahl Ranch, 20 miles northwest of the small town of Jordan, Mont.

"That was only the third specimen that was in any way complete that had ever been found," said paleontologist Lowell Dingus, who devoted a chapter to Garbani in his 2004 book, "Hell Creek, Montana: America's Key to the Prehistoric Past."

"He was certainly among the greatest fossil collectors that ever lived and the greatest one that I have ever known and worked with," said Dingus, who worked with Garbani while doing his dissertation fieldwork at UC Berkeley three decades ago.

During the summers from 1972 until several years ago, Garbani was part of the field crews of Berkeley's Museum of Paleontology that made trips to Montana.

"He not only collected fossil vertebrates but fossil clams and snails and plants," said Bill Clemens, a curator at the Berkeley museum who led the field trips.

"For us, one of the neat things that he found was the skull of a very young Triceratops, and already that's been a focus of research as a number of people have been looking into the patterns of growth of that dinosaur," Clemens said.

"He just had a sense for being able to find these amazing fossils — both large and small," Dingus said. "He was an expert not only at finding dinosaurs, but also finding very tiny teeth that are small enough that you study them under a microscope. These teeth were from the small mammals that lived in the shadows of the large dinosaurs.

"His skill at this wasn't simply based on luck. What he was able to do was figure out the kinds of rock layers and the kinds of outcrops that were most likely to have fossils because he had found them in similar-looking rock layers before."

Garbani was a welcome visitor to the sprawling ranch owned by Robert and Jane Engdahl — and to neighboring ranches — in the rugged hill country of the Missouri Breaks in Montana.

"He called the Hell Creek Bar" in Jordan "the office," Jane Engdahl said. "That's where he always met with these other bone diggers."

During the last four or five fossil-hunting trips Garbani made to the area, she said, "he'd have a potluck supper at the bar. He'd walk around with poker chips and give them to the friends to buy their drinks with. That would be 'Free drinks from Harley.'

"He was well-loved by everybody in Garfield County," she said.

Garbani — who had, among other things, a previously unknown gopher species and a small dinosaur named after him — received the Society of Vertebrate Paleontology's first Morris F. Skinner Award in 1990, in recognition of his fossil-collecting and contributions to science.

"He was a curious man, and that made him the expert that he was," said Mary Garbani. "I always said he was a humble man with nothing to be humble about."

Garbani was born Sept. 19, 1922, in Los Angeles and moved to the San Jacinto Valley in Riverside County when he was 3.

Growing up on a farm, he made his first find while trying to catch a pony when he was 8. "It was a large point, like part of a knife or spear," he told the Los Angeles Times in 2007. "I was hooked ever since."

A year later, his father was driving an earthmover and young Garbani was following behind when he made another discovery.

"It was a petrified bone, a femur. It came from a very large camel from the Pleistocene Age," he said. "I was 9 and had a collection going."

For many years, Garbani searched for Native American artifacts within a hundred-mile radius of the San Jacinto Valley.

He helped inspire a group to create the Western Science Center at Diamond Valley Lake near Hemet, where some of his archeological items have been displayed. His collection will be donated to the center, his wife said.

In addition to his wife of 11 years, he is survived by his son, David; three grandchildren; and four great-grandchildren.

A funeral service will be held at 10 a.m. Wednesday at Miller-Jones Mortuary, 1501 W. Florida Ave., Hemet.

Age of the Dinosaur exhibition opens Friday 22 April

Natural History Museum: Age of the Dinosaur exhibition opens Friday 22 April
The animatronic dinosaurs are lifelike enough, but the exhibition also brings to life their natural habitat, so visitors get immersed in Jurassic and Cretaceous environments along with weird and wonderful now extinct plants and animals.

As well as the animatronics, Age of the Dinosaur has CGI (computer generated images) film, stunning images, interactive stations, and amazing specimens, including real fossil dinosaur bones, to help visitors explore a world of more than 65 million years ago.

Well-preserved fossil of an Rhamphorhynchus, a flying reptile, or pterosaur.
And keep hold of your ticket as there is a NaturePlus barcode on it that lets you continue your dinosaur and fossil exploration back home on your computer.

Museum specimens
Age of the Dinosaur is rich with Museum specimens giving a taster of the important science work that goes on behind the scenes.

They come from the Museum’s world-class palaeontology collections and this is the first time in 5 years that so many have been used in a temporary exhibition.

Olympic gold medallist Denise Lewis OBE
Animatronics
The exhibition has 6 animatronic dinosaurs, and an animatronic Archaeopteryx, the earliest known bird.

The 1.5 tonne Tarbosaurus took 8 people and a forklift truck to get it safely into the Museum. They are produced by Kokoro, based in Tokyo, Japan.

Jurassic zone
In the Jurassic zone, see a huge tooth from a pliosaur, one of the many Jurassic marine monsters.

Find out more dinosaur facts and fun at the interactive stations
Along with plesiosaurs and ichthyosaurs, these menacing predators used their jagged, ridged teeth to gorge themselves on fish, squid and other sea creatures.

Take a look at a special fossil of a pterosaur. These flying reptiles had wings supported by a single long finger. They shared the air with birds and could fly as soon as they hatched.

The first dinosaur to come to life in the exhibition is a life-size Camarasaurus eating from the treetops of a Jurassic forest and calling to the rest of its herd.

Actor John Hannah
Cretaceous zone
In the Cretaceous zone, get a glimpse of some of the first flowering plants. Before the Cretaceous Period, plants only used seeds or spores to reproduce.

Examine the skull of a duck-billed dinosaur, Lambeosaurus lambei, that that had 700 teeth!

More life-size animatronic dinosaur scenes are waiting, including Protoceratops defending its nest and the tall, slim, ostrich-like Gallimimus.

Keep an eye out for Oviraptor and Velociraptor, two small, vicious meat-eating dinosaurs.

And the final dramatic Tarbosaurus, a cousin of T.rex, and every bit as scary.

Enjoy An Authentic Whiff Of Dinosaur (Coventry, UK)

CoventryTelegraph.net: Enjoy An Authentic Whiff Of Dinosaur
ANYONE who has ever wondered what a dinosaur would have smelled like can do so from today with the launch of a new animatronic exhibition.

The Age Of The Dinosaur at the Natural History Museum in London features a number of life-size and realistic-looking ancient beasts, complete with sound and smell.

The dinosaurs, including a Protoceratops and Velociraptor, are displayed in replications of their natural habitat from when they roamed the earth more than 65 million years ago.


Paul Barrett, of the museum's department of palaeontology, said the majority of the models were life-size, although some had to be scaled down.

He said: "The idea of the exhibition is actually trying to show dinosaurs in their natural environments alongside different sorts of plants and animals that we'd see at the same time, so rather than just concentrating on a particular dinosaur or a particular question relating to dinosaurs, we really want to give a view of what a dinosaur world would have been like.

"The animatronics are as realistic as we can possibly make them, so we use the latest scientific discoveries to inform everything about them from how they sound to the texture of their skin, and even these days we can say a little bit about dinosaur colour."

Mr Barrett said the roaring sounds that can be heard coming from the dinosaurs were based on living animals today.

He said: "We've been using a lot of information from, for example, our knowledge of how they hear to work out the sorts of sounds they could have heard, and then use examples from living animals to fill in the gaps about the sorts of noises we might expect to hear if we were wondering about Jurassic forests."

He added that visitors can press a button on some of the exhibits in order to be able to tell what the dinosaur would have smelt like.

The exhibition, which has been a year in development and lasts until September 4, also features 60 specimens from the museum's collections, including dinosaur bones.

Animated dinosaurs to visit Chester Zoo (UK)

Ellesmere Port Pioneer (United Kingdom): Animated dinosaurs to visit Chester Zoo
DINOSAURS will be seen at Chester Zoo this summer in what promises to be one of the most exciting and ground-breaking exhibits seen in a UK zoo.

The new exhibition, featuring 13 mechanical structures, will open in July.

Featuring movements and sounds, the dinosaurs will include the giant apatosaurus, with its long neck and whip-like tail, the evil-looking dilophosaurus, with its long, sharp claws and the infamous tyrannosaurus rex, the most feared land predator of all time.

The animated models will be part of an outdoor trail called Dinosaurs at Large! and will show visitors what it would have been like to get close to such huge beasts.

The event, which also aims to spread the message that once a creature is gone, it is gone forever, will run from July 1-October 8 and will be open every day from 10am-6pm.

Dinosaurs at Large! will be open to all visitors to Chester Zoo, with entry included in zoo admission charges.

For more details, visit www.chesterzoo.org

Everybody loves Tyrannosaurus

Guardian.co.uk: Notes & Theories, Dispatches from the Science Desk: Everybody loves Tyrannosaurus
wonder if Henry Fairfield Osborn created a self-fulfilling prophecy when he named Tyrannosaurus rex. The tyrant king is the most beloved and celebrated of all dinosaurs, and when the first specimen was put on display in 1906 – nothing more than the hips and legs – The New York Times declared Tyrannosaurus to be the "prize fighter of antiquity". It has held onto that top spot ever since.

But our love for Tyrannosaurus can be unhealthy. You don't need to look further than the headlines to see that the great Cretaceous predator has become the standard by which almost all of prehistory is judged. Dunkleosteus – a Devonian armoured fish – "had [a] bite stronger than a T. rex"; the invertebrate Hurdia was heralded as the "T. rex of the Cambrian period"; and, despite having a different shape, Colombia's fossil snake Titanoboa was said to be "as big as T. rex".

I'm almost convinced that there is a journalism guide that advises: "If a catchy headline doesn't readily present itself for a new fossil discovery, a reference to T. rex will do at a pinch."

Granted, such references to Tyrannosaurus are quick and easy ways to invoke the ferocity of extinct organisms, but our reliance on the tyrant becomes more problematic in stories about its dinosaurian kin. Upon making its debut last January, the early dinosaur Eodromaeus was dubbed the "earliest known T. rex relative", and, a few weeks later, the bizarre dinosaur Linhenykus was presented as a "one-fingered T. rex relative". Then, just last month, the dinosaur Zhuchengtyrannus was announced to be "T. rex's new cousin".

The phrases "T. rex relative" and "T. rex cousin" are thrown around so often that they have nearly lost their meaning. Citing the news of Zhuchengtyrannus as a "T. rex cousin", NPR blogger Bill Chappell wrote "It's exciting news, but doesn't it seem like we've heard something similar recently?" He wondered why both Linhenykus and the small tyrannosaur Raptorex had been given the same honorary title.

Dinosaurs have become victims of their own success. The pace of dinosaur discoveries is so rapid – and requires so much context – that journalists simply can't keep up. Only the truly exceptional, eye-grabbing stories make it to press, and when they do the stories are typically along the lines of "New dinosaur discovered. Cousin of [famous dinosaur]. Ooooh."

The tyrannosaurs themselves provide perfect examples. For decades Tyrannosaurus, Albertosaurus, Daspletosaurus, and other tyrants were considered to be "Carnosaurs" – a grab-bag group of giant predators that also included Allosaurus, Spinosaurus, and others. Palaeontologists have since split up this dinosaurian mish-mash into a branching tree of theropod dinosaurs.

As is now understood, tyrannosaurs fit inside a highly diverse theropod subgroup called coelurosaurs, which also encompass small, sickle-clawed hunters (Velociraptor); long-necked herbivores with Freddy Krueger claws (Therizinosaurus); ostrich-mimics (Gallimimus); and birds, among others. Even better, within the past 10 years palaeontologists have found a wealth of tyrannosaurs that document the group's evolution from small, feather-covered creatures to some of the largest predators of all time. Zhuchengtyrannus is only the latest tyrannosaur to be welcomed into the family.

Both Eodromaeus and Linhenykus were only distant relatives of Tyrannosaurus. Eodromaeus preceded tyrannosaurs by over 165m years, and was about as closely related to the tyrants as to any other giant, badass theropod you care to name. Linhenykus, on the other claw, belonged to a coelurosaur lineage called alvarezsaurs which were not notably close to the tyrants.

The true "T. rex cousins" were found among the tyrannosauroids – a group that included everything from the pint-sized, fuzzy-feathered Dilong to large, deep-snouted apex predators such as Tyrannosaurus and the recently described Teratophoneus.

In a review of tyrannosaurs published last September, a team of theropod experts noted that at least six new tyrants had been named within a year of their paper's debut, and two more have been named since then. (More are on the way – attendees at last year's Society for Vertebrate Paleontology meeting in Pittsburgh got a preview of a new, as-yet-unnamed tyrant.)

Yet the flock of new tyrants does not give us a complete explanation for the confusion about these dinosaurs. Tyrannosaurus – along with Triceratops, Stegosaurus, Apatosaurus and Edmontosaurus – represents one of the primary dinosaur archetypes that have been popularised for over a century. They are THE dinosaurs, and their long shadows obscure recently discovered species that have led palaeontologists to revise our understanding of dinosaur evolution and relationships.

Take Linhenykus, for example. Who – other than palaeontologists – knows what an alvarezsaur is? From a writer's perspective, it is easier to play up its tenuous connection to Tyrannosaurus than spend a paragraph explaining the dinosaur's unique nature. It doesn't fit in the already established set of familiar dinosaur shapes, so a well-known dinosaur is used to make the introduction.

As science writers, we face the difficult task of condensing technical details into compelling, easily accessible stories that will hopefully catch the eyes of readers before they click over to another webpage. That doesn't mean that we should shrink from accuracy. We are not doing our jobs if we simply refer every sharp-toothed dinosaur to the tyrant family because Tyrannosaurus provides a solid hook. If we fall victim to this trope, we perpetuate a cycle in which no one will understand what an alvarezsaur is because we never explain it and we never explain it because we don't think anyone will understand.

There will always be more dinosaur discoveries than available media space to disseminate their details. That is true of any scientific discipline, and it is why context has become so vital. Our reliance on Tyrannosaurus as an attention-grabbing anchor is just one symptom of a more pervasive affliction in which brevity and page views are valued over placing news in context.

Palaeontologists are not exempt, either. Too often – from grant applications to press releases – we have relied upon the cultural cachet of Tyrannosaurus to get attention.

There is more to palaeontology than Tyrannosaurus rex. Just as the tyrant king was just one member of a rich and diverse dinosaurian family, so are new scientific discoveries intimately connected to the ongoing interrogation of nature. We would do well to remember that.

Brian Switek is the author of Written in Stone: Evolution, the Fossil Record, and Our Place in Nature. He writes for the WIRED Science blog Laelaps and Smithsonian magazine's Dinosaur Tracking

References
Brusatte, SL et al (2010). Tyrannosaur Paleobiology: New Research on Ancient Exemplar Organisms. Science (New York, N.Y.); 329 (5998): 1481-1485. DOI: 10.1126/science.1193304
Hone, D et al (2011). A new tyrannosaurine theropod, Zhuchengtyrannus magnus is named based on a maxilla and dentary. Cretaceous Research (in press). DOI: 10.1016/j.cretres.2011.03.005
Martinez, R et al (2011). A Basal Dinosaur from the Dawn of the Dinosaur Era in Southwestern Pangaea. Science; 331 (6014): 206-210. DOI: 10.1126/science.1198467
Nesbitt, S et al (2011). A small alvarezsaurid from the eastern Gobi Desert offers insight into evolutionary patterns in the Alvarezsauroidea. Journal of Vertebrate Paleontology; 31 (1): 144-153. DOI: 10.1080/02724634.2011.540053

UC Davis dinosaur eye bone study offers new view

SFGate: UC Davis dinosaur eye bone study offers new view

In the long-ago age of the dinosaurs, the smaller, fierce and predatory beasts were night hunters, stalking and seizing their unwary prey in the dark, while giant plant eaters of the same era browsed both day and night in order to fill the energy needs of their huge bodies.

This new picture of dinosaur behavior - based on studies of the fossil bony structures of their eyes - has been drawn by paleontologists at UC Davis, and it challenges some long-held ideas about the way dinosaurs lived.

Lars Schmitz, a postdoctoral researcher, and Ryosuke Motani, an evolutionary biologist at Davis, developed an ingenious approach to their study.

They measured the fossil eye bones of 33 varied dinosaurs, including those that lived on land like velociraptor of movie fame and archaeopteryx, the first flying bird, as well as diplodocus, the long-necked land giant that gorged on leaves and ferns and all sorts of other vegetation.

They also examined the eye bones of 164 modern birds, because the birds - as dinosaur experts now maintain - are, in fact, living dinosaurs.

Within the bony eye sockets of all those animals is a circular bone called the scleral ring; the ring is larger around large eyes and smaller when eyes are smaller. Big eyes let in more light allowing animals to see in the dark; smaller eyes are all that's needed to see clearly in daylight.

So Schmitz and Motani measured the scleral rings in all the fossil beasts they could find, and in the modern birds, too, and they concluded that the bony rings are excellent clues to the feeding habits of the dinosaurs.

In the movie "Jurassic Park," the savage velociraptors were pictured as hunting their prey only at night, but that image annoyed many scientists, for conventional wisdom held that the carnivorous beasts only attacked by day.

But velociraptor fossils show large scleral rings in their skulls - suggesting their large eyes helped them to prey on the small mammals for food at night. So, it seems, the makers of "Jurassic Park" were right.

And diplodocus, the huge plant eaters with the long, snake-like necks, had smaller scleral rings, indicating they must have been actively feeding most of the day and evening - except for the hottest sunshine hours when their bodies needed to avoid overheating, the scientists concluded.

Flying dinosaurs like archaeopteryx were daylight hunters, the analysis showed, although some modern birds that hunt at night have large scleral rings, Schmitz said.

Mark Goodwin, assistant director of the Museum of Paleontology at UC Berkeley and an expert on dinosaur bone growth, said the Davis scientists developed "a creative and innovative technique" to infer the activity patterns and behavior of the dinosaurs.

The researchers also have shown that earlier notions of dinosaurs as daylight hunters "may be, at best, very simplistic and most likely not entirely accurate," Goodwin said.

"I like the study," he said.

Schmitz and Motani published two reports of their study last week, in Science Express and in the journal Evolution.