Raptor Red Read online

  Raptor Red by Robert T. Bakker

  *****

  RAPTOR RED

  scanned by torinoblue

  ISBN 0-553-50369-3

  This book is dedicated to all the amateur fossil-hunters who donate their weekends and vacations to enlarging our appreciation of the past. In Wyoming we call them the 'Jurassic Irregulars.' They work long hours without museum salaries, without government grants, and all too often without appreciation from the Ph.D.s, and. yet these amateurs are discovering new dinosaur species every summer.

  Most of the time they pay for their own gas and drive their own pickups into the badlands. When we open up a new quarry, they contribute bags of plaster and bundles of burlap. Those of us fortunate enough to work full-time in small western museums rely on volunteers at every stage in the exacting process of cleaning the fossils, interpreting the anatomical facts, and clothing the bones with flesh and skin.

  I started thinking about Raptor Red when I heard that a veteran amateur fossil-hunter had discovered a remarkable dinosaur. Raptor Red has come back to life thanks to such people.

  RAPTOR RED

  Foreword

  'Call her Utahraptor.'

  That's what I suggested to my colleague, Dr James Kirkland of the Dinamation Society, over the phone on a January afternoon in 1992. Jim was ecstatic about a giant fossil claw just dug up by a talented amateur, Bob Gaston, in red-gray rocks of Early Cretaceous Age. It was a raptor claw.

  The bone bed was in Utah, a state with a glorious history ofdino discoveries, so the name Utahraptor popped into my head. And for some reason I automatically thought of the beast as a female.

  'Why don't you call her Utahraptor? You know, "The Hunter of Ancient Utah."' He did.

  I knew raptors well. When I was a freshman at college, back in 1964,1 helped excavate a raptor pod in Montana -four skeletons intertwined in death, each animal about nine feet long and maybe 120 pounds weight when alive. Raptors were bantamweight dinosaurs, small and compact in the body but equipped with weapons of exceptional deadliness. They were kick-boxers. One claw on each hindfoot was transformed into a big curved knife that could disembowel prey with a single stroke.

  These Montana creatures were named Deinonychus - 'terrible claw.' Speed and agility were other raptor characteristics. The first raptor species ever found was the 'Mongolian speedy raptor/ Velociraptor mongoliensis, excavated from the fossil sand dunes of the Gobi Desert in the 1920s. Velociraptor was even smaller than the deinonychs, only fifty pounds or less. But Velociraptor shins and ankles were long and strong, a design specification that ensured high running speed. And all the raptor species had tails that ended in elongated stiff rods, balancing poles that let the animal engage in all sorts of nimble acrobatics.

  It became customary in some paleontological circles to use 'velociraptor'for all the species in the family. Or just simply 'raptor.'

  All raptor species were masters of martial arts. They could twist and turn while running at high speed, and they had the capacity to jump while changing direction in midair. Raptor hands were powerful and supple too -the combination of hand claws for grabbing and hind-claws for kicking was formidable.

  The raptor family was exceptional among the Dinosauria for yet another reason: These were smart carnivores. In the 1960s, anatomists probed the inside of raptor braincase bones and found to their surprise that the raptor's brain was as large for its body weight as it is in many modern ground-running birds.

  Finding any raptor bone is a treat for us bone-diggers. But what Gaston and Kirkland had just identified in their workshop was something so spectacular, no scientist had ever dreamed of it. They had found the first giant raptor.

  Their claw was from a beast twice the size of any other member of the family and must have been carried by a body five hundred to a thousand pounds - eight times heavier than a deinonych. It was the find of a lifetime.

  'The claw we've got - it's huge!' I could hear Jim jumping up and down at the other end of the line, and I started jumping up and down too, because I knew something he didn't. 'Jim, Jim- Jim! 'I yelled. 'You just found Spielberg's raptor.'

  'Huh?'

  'You just found the giant raptor Spielberg made up for his movie, you know - Jurassic Park.'

  Jim thought I was daft. He didn't know about the other phone call I had gotten about giant raptors that morning. It was from one of the special effects artists working in the Jurassic Park skunk works, the studio where the movie monsters for Spielberg's film were being fabricated in hush-hush conditions. The artists were suffering secret anxiety about what was to become the star of the movie -a raptor species of a size that had never been documented by a real fossil.

  No one outside the studio besides me knew about the problem with Spielberg's giant raptor. No professional dinosaurologist was aware of the supersize raptor being manufactured for the movie.

  The special-effects artists were superb dino-anatomists. It's funny how some of the best thinking about dinosaur shape and dinosaur movement have come from movie artists. Even the 1933 King Kong had some brontosaur sequences that were a generation ahead of the dinosaurian dogma taught at the time in universities. The artists doing Jurassic Park wanted the latest info on all the species they were reconstructing They wanted everything to be right. They'd been calling me once a week for months, checking on teeth of T. rex and skin of Triceratops. I'd sent them dozens of pages of dino-details.

  The artists were up to date in their raptor knowledge.

  They knew that deinonychs were the largest, and that no raptor was bulkier than the average adult male human. Just before Jim called, I'd listened to one artist complain that Spielberg had invented a raptor that didn't exist. Apparently Spielberg wasn't happy with the small size of'real' raptors - he wanted something bigger for his movie. He wanted a raptor twice as big as Deinonychus.

  I'd tried to calm the artist's misgivings. 'You know, evolution can change size real fast. It's not impossible that a giant raptor could evolve in a geological instant. So maybe, theoretically, Spielberg's oversize raptor could have happened.'

  The artist wasn't impressed with my learned argument. He wanted hard facts, fossil data. 'Yeah, a giant raptor's possible - theoretically. But you don't have any bones.'

  But now Jim's Utahraptor gave him the bones. The fossil beast from Utah turned out to be almost exactly the same size as the biggest raptor in the movie, an animal referred to in the script as the 'bigfemale.'

  Jim got back to work at the quarry, assisted by Don Birge, director of the museum at Price, Utah. Soon Don and Jim's crews had hand bones, foot bones, backbone, shinbones, and parts of the muzzle of their superraptor. They made a quick sketch of the entire critter, nose to tail. Not only was the Utahraptor huge by raptor standards, but it carried the most lethal weapons in its hands. The foreclaws had much sharper edges and worked like a set of six recurved carving knives.

  In a few weeks Utah's giant raptor made the front page of The New York Times. And Utahraptor penetrated the worldwide community of dinosaur lovers - within a few days of the announcement, kids and adults all over the world knew the name. The giant raptor was fast becoming the second most famous dinosaurian meat-eater. The first, of course, is still Tyrannosaurus rex.

  When the movie Jurassic Park came out at the beginning of the summer of 1993, it became the biggest blockbuster ever and made velociraptor a household word. A significant percentage of the moviegoing public knew that the true star was more accurately called Utahraptor.

  This book is the story of Utahraptor, told through the experiences of an individual raptor, a young adult female. Her story is pieced together from the fossil remains of Utahraptor and from clues about her world locked up in Early Cretaceous sediments.

  Bones and rocks are eloquent
storytellers, if you know how to listen to them. When you pick up a raptor shin-bone, you can feel the rough textured zones that mark the attachment sites of the muscles that gave power to the leg when it was part of a living animal. You can run your finger around the smooth surfaces at the upper and lower ends of the bone - the areas that formed the joints and that allowed quick, controlled movement.

  Bones, muscles, and joints tell us much about the life and times of the superraptor from Utah - and we can learn even more from living species who have raptor characteristics today. Dinosaurs weren't the slow, stupid, overgrown lizards that museum displays showed in the 1950s. AH dinosaurs show at least some of the adaptive hallmarks of the bird class. Raptors are especially close. In all details of their body construction - hips, knees, ankles, feet and hands, eyes and brain - raptors are designed like ground-running superhawks.

  If you want to imagine the courtship behavior of Utahraptors or how they raised their young, don't think 'lizard'- think 'bird.'

  The rocks of Utah are full of clues as to what sort of landscape played host to Utahraptor. Fossils of water-loving turtles, crocs, and clams map out the size of rivers and ponds and swamps of the Early Cretaceous. Petrified tree trunks and shale beds with leaf imprints give snapshots of the flora. The very same sand beds and floodplain silts that entomb Utahraptor bones tell offloads that covered the lowlands during spring rainy seasons and of terrible droughts that turned lakes into briny salt flats.

  Even such lowly creatures as earthworms and beetle grubs, the subterranean supporting cast of landscape evolution, left behind fossilized burrows that show up as bright green zones in the brown and red mud rock. When you sit in a dinosaur quarry in Utah, taking a break from chiseling out raptor bones, you can almost hear the gentle rustling of Cretaceous soil creatures, churning around the tangled roots of conifer seedlings.

  We can learn from Utahraptor's story. Hers was a beautifully alert and sentient species. By looking through her eyes, we can see the evolutionary forces that were changing the natural world during the Early Cretaceous. Our own human ancestors were being created by the invisible hand of natural selection, as were the beginnings of the other animals and plants that enjoy supremacy in today's world. Utahraptor's story is part of our story.

  The story begins with an invasion, an ambush, and a death.

  The time is a hundred and twenty million years ago. On the flat, featureless flood plains that were central Utah, an evolutionary event is about to occur that will shock the ecological community of dinosaurs. The event is the arrival of a new superpredator.

  RAPTOR ATTACK

  APRIL

  A pair of fierce but beautiful eyes look out from the dull green undergrowth of conifers and ferns that bound the edges of mud flats and riverbeds. The eyes follow every movement among the great herd of plant-eating dinosaurs that mills around in the open meadows, feeding high in the trees, and sniffing the air for danger. The eyes belong to a young adult Utahraptor, a female who has not yet reproduced.

  The female Utahraptor moves her twenty-foot-long body quietly through the ferns, walking in long, slow strides on her muscular hindlegs. She stops every few steps, rotates her elongate head, surveys the plant-eaters. Her eyes move back and forth, executing the rapid scanning of a hunter who is thinking about everything she sees. She is an intelligent killer. She watches the pattern made by the huge herbivorous dinosaurs. She evaluates each individual as a potential victim.

  If she could put her thoughts into a human language, they might be: That cow over there is too alert -she travels with two near full-grown calves. They're too strong, too dangerous to attack.

  And that young bull is part of a bachelor-pack, five adolescent males who are aggressive and inquisitive. We can't kill them today.

  The Utahraptor moves her muzzle slightly to the left. She searches the treeline for another pair of eyes.

  There! She exhales in a short, barely audible grunt. Her eyes meet those of another Utahraptor, a young male. He has the same stocky, compact torso she has, the same long, low head, the same neck held in an S-curve, the same long arms and fingers tipped with cruel-looking claws.

  She is half of a mated pair, locked together in Darwinian monogamy for the last six months. Their mutual attraction is evolution's way of giving both male and female the best possible chance to get their genes into the next Utahraptor generations. In nature, nothing else matters.

  As the days have lengthened in the early spring, the female Utahraptor has been responding to a powerful shift in her own internal chemistry. During the winter she was hunting for herself and for her mate. But now, subconsciously, she's aware of a new responsibility. She is hunting for the next generation. Soon they must build a nest and they must raise chicks.

  The female and male exchange glances again, and she nods to him. It's a message that means, In the next few minutes our lives will depend upon each other. I'm with you.

  The raptor pair-bond is held together by these shared risks. If they're efficient as a pair - and lucky - they'll be uninjured and well fed at the breeding season. Then and only then will there be a brief interval for copulation.

  This is the most dangerous season for raptors. Mating and rearing young exposes both parents to the highest risk of injury and death they'll face all year. Hunting alone isn't good enough. A pair of raptors hunting together is four or five times more successful than a solitary predator.

  The raptor pair have another reason to be anxious. They are newcomers to the Utah ecosystem, an immigrant species whose original home is thousands of miles away in northern Asia. The native prey species of North America have strange habits and may be equipped with defenses the new predators have never seen.

  The female Utahraptor sniffs the dung heaps left by the plant-eaters at the edge of the treeline. She's searching for identification chemicals, clues to the nature of the animals she and her mate are stalking. She's reluctant to risk an attack on a herbivore whom she has never met. But she's optimistic today - the dung-aroma seems familiar.

  She has learned that she and her mate often have the advantage in the new land - sometimes the native prey species haven't had time to evolve special countermeasures against the foreign hunters. Invading predators may hit new territory like a Darwinian blitzkrieg.

  The female raptor sticks her narrow snout out between the dried fronds of a tree fern. The dull brown-red hue of the fronds matches her own body color. She sniffs the air, testing the prey's chemical signature - she trusts identification by smell more than by sight.

  I know this one. We've hunted it before. We can do it if we're careful. Her thought processes click through her predatory options. She knows her mate is smart. She trusts that he knows what she knows.

  There. That one. That bull acting alone, bullying the cows. He's not paying attention - we can kill him. The female raptor silently selects the target, wordlessly evaluating the bull's vulnerability.

  Her thigh muscles begin to twitch. It's almost time. They're almost close enough.

  She pauses one last time, sitting up inside a clump of tall tree ferns. She looks back again at her mate. They're too close to their prey to exchange nods, but just looking at each other is reassurance enough.

  Her target is the biggest of the herbivores in the Utah ecosystem, an Astrodon ('star tooth'), a bronto-saurian species with a long neck, a long tail, and a torso built like a ten-ton elephant's.

  Giant size confers a certain ecological arrogance, and astros have a swaggering disdain for predators. In the astro's mind, any carnivore would be foolish to attack. Millions of years of evolution have built into their brains the comforting knowledge that they face hardly any real threat from meat-eaters. The only giant carnivore species is the ridge-backed acro, Acrocanthosaurus, but these three-ton hunters are very rare.

  Even if a full-grown acro did try to attack an astrodon herd, the combined defenses of a dozen astros, totaling more than a hundred tons of enraged vegetarians, would be impregnable.

&nbs
p; As the astro herd ambles easily around the edges of the salt lake bed, their big cushioned paws churning up the briny mud, brains routinely check sensory input for danger. No scents are alarming. They pick up the hint of a raptor a hundred yards away, but raptors are eighty-pound predators that wouldn't dare challenge a twenty-thousand-pound bull astro. The resident raptor species is the commonest predator in the astros' world, and the big plant-eaters see or smell them every day. All the raptors are tiny compared with the star-toothed brontosaurs. Never would the biggest raptor, a 150-pounder, even dream of attacking astros, unless it was lucky enough to find an unguarded newborn calf.

  There is a raptor pack ahead, chewing up the carcass of a five-hundred-pound plant-eater (an iguanodont species), but they slink away when a cow astro makes a mock-charge in their direction.

  The astro brains go down their genetically programmed checklist for sounds. There's no cause for alarm coming from this sensory system either. A low undertone of crunching can be made out to the left, under some conifer trees, where a one-ton armor-plated nodosaur is feeding placidly on seedlings. No threat here - the nodosaur moves away when a young bull astro pushes through the trees to investigate.