The Valley

"This is going extremely well," Levine said, rubbing his hands together. "Far beyond my expectations, I must say. I couldn't be more pleased."

He was standing in the high hide with Thorne, Eddie, Malcolm, and the kids, looking down on the valley floor below. Everyone was sweating inside the little observation hut; the midday air was still and hot. Around them, the grassy meadow was deserted; most of the dinosaurs had moved beneath the trees, into the cool of the shade.

The exception was the herd of apatosaurs, which had left the trees to return to the river, where they were now drinking once again. The huge animals clustered fairly tightly around the water's edge. In the same vicinity, but more spread out, were the high-crested parasaurolophasaurs; these somewhat smaller dinosaurs positioned themselves near the apatosaur herd.

Thorne wiped sweat out of his eyes and said, "Why, exactly, are you pleased?"

"Because of what we're seeing here," Malcolm said. He glanced at his watch, and wrote an entry in his notebook. "We're getting the data that I hoped for. It's very exciting."

Thorne yawned, sleepy in the heat. "'Why is it exciting? The dinosaurs are drinking. What's the big deal?"

"Drinking again," Levine corrected him. "For the second time in an hour. At midday. Such fluid intake is highly suggestive of the thermoregulatory strategies these large creatures employ."

"You mean they drink a lot to stay cool," Thorne said, always impatient with jargon.

"Yes. Clearly they do. Drink a lot. But in my view, their return to the river may have another significance entirely."

"Which is?"

"Come, come," Levine said, pointing. "Look at the herds. Look how they are arranged spatially. We are seeing something that no one has witnessed before, or even suspected, for dinosaurs. We're seeing nothing less than inter-species symbiosis."

"We are?"

Yes," Levine said. "The apatosaurs and the parasaurs are together. I saw them together yesterday, too. I'll bet that they're always together, when they're out on the open plain. Undoubtedly you are wondering why."

"Undoubtedly," Thorne said.

"The reason," Levine said, "is that the apatosaurs are very strong but weak-sighted, whereas the parasaurs are smaller, but have very sharp vision. So the two species stay together because they provide a mutual defense. just the way zebras and baboons stay together on the African plain. Zebras have a good sense of smell, and baboons have good eyesight. Together they're more effective against predators than either is alone."

"And you think this is true of the dinosaurs because..."

"It's rather obvious," Levine said. "Just look at the behavior. When the two herds were alone, each clustered tightly among themselves. But when they're together, the parasaurs spread out, abandoning their former herd arrangement, to form an outer ring around the apatosaurs. Just as you see them now. That can only mean that individual paras are going to be protected by the apatosaur herd. And vice versa. It can only be a mutual predator defense."

As they watched, one of the parasaurs lifted its head, and stared across the river. It honked mournfully, a long musical sound. All the other parasaurs looked up and stared, too. The apatosaurs continued to drink at the river, although one or two adults raised their long necks.

In the midday heat, insects buzzed around them, Thorne said, "So where are the predators?"

"Right there," Malcolm said, pointing toward a stand of trees on the other side of the river, not far from the water.

Thorne looked, and saw nothing.

"Don't you see them?"

"No."

"Keep looking. They're small, lizard-like animals. Dark brown. Raptors," he said.

Thorne shrugged. He still saw nothing. Standing beside him, Levine began to eat a power bar. Preoccupied with holding the binoculars, he dropped the wrapper on the floor of the hide. Bits of paper fluttered to the ground below.

"How are those things?" Arby said.

"Okay. A little sugary."

"Got any more?" he said.

Levine rummaged in his pockets and gave him one. Arby broke it in half, and gave half to Kelly. He began to unwrap his half, carefully folding the paper, putting it neatly in his pocket.

"You realize this is all highly significant," Malcolm said. "For the question of extinction. Already it's obvious that the extinction of the dinosaurs is a far more complex problem than anyone has recognized."

"It is?" Arby said.

"Well, consider," Malcolm said. "All extinction theories are based on the fossil record. But the fossil record doesn't show the sort of behavior we're seeing here. It doesn't record the complexity of groups interacting."

"Because fossils are just bones," Arby said.

"Right. And bones are not behavior. When you think about it, the fossil record is like a series of photographs: frozen moments from what is really a moving, ongoing reality. Looking at the fossil record is like thumbing through a family photo album. You know that the album isn't complete. You know life happens between the pictures. But you don't have any record of what happens in between, you only have the pictures. So you study them, and study them. And pretty soon, you begin to think of the album not as a series of moments, but as reality itself. And you begin to explain everything in terms of the album, and you forget the underlying reality.

"And the tendency," Malcolm said, "has been to think in terms of physical events. To assume that some external physical event caused the extinctions. A meteor hits the earth, and changes the weather. Or volcanoes erupt, and change the weather. Or a meteor causes the volcanoes to erupt and change the weather. Or vegetation changes, and species starve and become extinct. Or a new disease arises, and species become extinct. Or a new plant arises, and poisons all the dinosaurs. In every case, what is imagined is some external event. But what nobody imagines is that the animals themselves might have changed-not in their bones, but their behavior. Yet when you look at animals like these, and see how intricately their behavior is interrelated, you realize that a change in group behavior could easily lead to extinction."

"But why would group behavior change?" Thorne said. "If there wasn't some external catastrophe to force it, why should the behaviour change?"

"Actually," Malcolm said, "behavior is always changing, all the time. Our planet is a dynamic, active environment. Weather is changing. The land is changing. Continents drift. Oceans rise and fall. Mountains thrust up and erode away. All the organisms on the planet are constantly adapting to those changes. The best organisms are the ones that can adapt most rapidly. That's why it's hard to see how a catastrophe that produces a large change could cause extinction, since so much change is occurring all the time, anyway."

"In that case," Thorne said, "what causes extinction?"

"Certainly not rapid change alone," Malcolm said. "The facts tell us that clearly."

"What facts?"

"After every major environmental change, a wave of extinctions as usually followed-but not right away. Extinctions only occur thousands, or millions of years later. Take the last glaciation in North America. The glaciers descended, the climate changed severely, but animals didn't die. Only after the glaciers receded, when you'd think things would go back to normal, did lots of species become extinct. That's when giraffes and tigers and mammoths vanished on this continent. And that's the usual pattern. It's almost as if species are weakened by the major change, but die off later. It's a well-recognized phenomenon."

"It's called Softening Up the Beachhead," Levine said. "And what's the explanation for it?"

Levine was silent.

"There is none" Malcolm said. "It's a paleontological mystery. But I believe that complexity theory has a lot to tell us about it. Because if the notion of life at the edge of chaos is true, then major change pushes animals closer to the edge. It destabilizes all sorts of behavior. And when the environment goes back to normal, it's not really a return to normal. In evolutionary terms, it's another big change, and it's just too much to keep up with. I believe that new behavior in populations can emerge in unexpected ways, and I think I know why the dinosaurs - "

"What's that?" Thorne said.

Thorne was looking at the trees, and saw a single dinosaur hop out into view. It was rather slender, agile on its hind legs, balancing with a stiff tail. It was six feet tall, green-brown with dark-red stripes, like a tiger.

"That," Malcolm said, "is a velociraptor."

Thorne turned to Levine. "That's what chased you up in the tree? It looks ugly."

"Efficient," Levine said. "Those animals are brilliantly constructed killing machines. Arguably the most efficient predators in the history of the planet. The one that just stepped out will be the alpha animal. It leads the pack."

Thorne saw other movement beneath the trees. "There's more."

"Oh yes," Levine said. "This particular pack is very large." He picked up binoculars, and peered through them. "I'd like to locate their nest, he said. "I haven't been able to find it anywhere on the island. Of course they're secretive, but even so..."

The parasaurs were all crying loudly, moving closer to the apatosaur herd as they did so. But the big apatosaurs seemed relatively indifferent; the adults nearest the water actually turned their backs to the approaching raptor.

"Don't they care?" Arby said. "They're not even looking at him,"

"Don't be fooled," Levine said, "the apatosaurs care very much. They may look like gigantic cows, but they're nothing of the sort. Those whiptails are thirty or forty feet long, and weigh several tons. Notice how fast they can swing them. One smack from those tails would snap an attacker's back."

"So turning away is part of their defense?"

"Unquestionably, yes. And you can see now how the long necks balance their tails."

The tails of the adults were so long, they reached entirely across the river, to the other shore. As they swung back and forth, and the parasaurs cried out, the lead raptor turned away. Moments later, the entire pack began to slink off, following the edge of the trees, heading up into the hills.

"Looks like you're right," Thorne said. "The tails scared them off."

"How many do you count?" Levine said.

"I don't know. Ten. No, wait - fourteen. Maybe more. I might have missed a few."

"Fourteen." Malcolm scribbled in his notebook.

"You want to follow them?" Levine said.

"Not now."

"We could take the Explorer."

"Maybe later," Malcolm said.

"I think we need to know where their nest is," Levine said. "It's essential, Ian, if we're going to settle predator-prey relationships. Nothing is more important than that. And this is a perfect opportunity to follow - "

"Maybe later," Malcolm said. He checked his watch again.

"That's the hundredth time you've checked your watch today," Thorne said.

Malcolm shrugged. "Getting to be lunchtime," he said. "By the way, what about Sarah? Shouldn't she be arriving soon?"

"Yes. I imagine she'll show up any time now," Thorne said.

Malcolm wiped his forehead. "It's hot up here."

"Yes, it's hot."

They listened to the buzzing of insects in the midday sun, and watched the raptors retreat.

"You know, I'm thinking," Malcolm said. "Maybe we ought to go back."

"Go back?" Levine said. "Now? What about our observations? What about the other cameras we want to place and - "

"I don't know, maybe it'd be good to take a break."

Levine stared at him in disbelief. He said nothing.

Thorne and the kids looked at Malcolm silently.

"Well, it seems to me," Malcolm said, "that if Sarah's coming all the way from Africa, we should be there to greet her." He shrugged. "I think it's simple politeness."

Thorne said, "I didn't realize that, uh..."

"No, no," Malcolm said quickly. "It's nothing like that. I just, uh...You know, maybe she's not even coming." He looked suddenly uncertain. "Did she say she was coming?"

"She said she'd think about it."

Malcolm frowned. "Then she's coming. If Sarah said that she's corning. I know her. So. What do you say, want to go back?"

"Certainly not," Levine said, peering through binoculars. "I wouldn't dream of leaving here now."

Malcolm turned. "Doc? Want to go back?"

"Sure," Thorne said, wiping his forehead. "It's hot."

"If I know Sarah," Malcolm said, climbing down the scaffolding, she's going to show up on this island just looking great."

Cave

She struggled upward, and her head broke the surface, but she saw only water - great swells rising fifteen feet above her, on all sides. The power of the ocean was immense. The surge dragged her forward, then back, and she was helpless to resist. She could not see the boat anywhere, only foaming sea, on all sides. She could not see the island, only water. Only water. She fought a sense of overwhelming panic.

She tried to kick against the current, but her boots were leaden. She sank down again, and struggled back, gasping for air. She had to get her boots off, somehow. She gulped a breath and ducked her head under the water, and tried to unlace the boots. Her lungs burned as she fumbled with the knots. The ocean swept her back and forth, ceaselessly

She got one boot off, gulped air, and ducked down again. Her fingers were stiff with cold and fright, as she worked on the other boot. It seemed to take hours. Finally her legs were free, light, and she dogpaddled, catching her breath. The surge lifted her high, dropped her again. She could not see the island. She felt panic again. She turned, and felt the surge lift once more. And then she saw the island

The sheer cliffs were close, frighteningly close. The waves boomed as they smashed against the rocks. She was no more than fifty yards offshore, being swept inexorably toward the crashing surf On the next crest, she saw the cave, a hundred yards to her right. She tried to swim toward it, but it was hopeless. She had no power at all to move in this gigantic surf. She felt only the strength of the sea, sweeping her to the Cliffs.

Panic made her heart race. She knew she would be instantly killed. A wave crested over her; she gulped sea water, and coughed. Her eyes blurred. She felt nausea and deep, deep terror.

She put her head down and began to swim, arm over arm, kicking as hard as she could. She had no sense of movement, only the sideways pull of the surge. She dared not look up. She kicked harder. When she raised her head for another breath, she saw she had moved a little - not much, but a little - to the north. She was a little nearer to the cave.

She was encouraged, but she was terrified. She had so little strength! Her arms and legs ached with her effort. Her lungs burned. Her breath came in short ragged heaving gasps. She coughed again, grabbed another breath, put her head down and kicked onward.

Even with her head in the water, she heard the deep boom of the surf against the cliffs. She kicked with all her might. The currents and surge moved her left and right, forward and back. It was hopeless. But still she tried.

Gradually, the ache in her muscles became a steady drill pain. She felt she had lived with this pain all her life. She did not notice it any more. She kicked on, oblivious.

When she felt the surge lift her up again, she raised her head for a breath. She was startled to see that the cave was very close. A few more strokes and she would be swept inside it. She had thought the current might be less severe around the cave. But it wasn't; on either side of the opening, the waves crashed high, climbing the cliff walls, and then falling back. The boat was nowhere in sight.

She ducked her head down again, kicked forward, using the last of her strength. She could feel her entire body weakening. She could not last much longer. She knew she was being carried toward the cliffs. She heard the boom of the surf louder now, and she kicked again, and suddenly a huge swell swept her up, lifting her, carrying her toward the cliffs. She was powerless to resist it. She raised her head to look, and saw darkness, inky darkness.

In her exhaustion and pain, she realized that she was inside the cave. She had been swept into the cave! The booming sound was hollow, reverberating. It was too dark to see the walls on either side. The current was intense, sweeping her ever deeper. She gasped for breath and paddled ineffectually. Her body scraped against rock; she felt a moment of searing pain, and then she was swept farther into the depths of the cave. But now there was a difference. She saw faint light on the ceiling, and the water around her seemed to glow. The surge lessened. She found it easier to keep her head above water. She saw hot light ahead, brilliantly hot - the end of the cave.

And suddenly, astonishingly, she was carried through, and burst into sunlight and open air. She found herself in the middle of a broad muddy river, surrounded by dense green foliage. The air was hot and still; she heard the distant cries of jungle birds.

Up ahead, around a bend in the river, she saw the stern of Dodgson's boat, already tied up to the shore. She could not see any of the people, and she didn't want to see them.

Summoning her remaining strength, she kicked toward shore, and clutched at a stand of mangroves, growing thickly along the water's edge. Too weak to hold on, she hooked her arm around a root, and lay on her back in the gentle current, looking up at the sky, gasping for breath. She did not know how much time passed, but finally she felt strong enough to haul herself arm over arm along the mangrove roots at the water's edge, until she came to a narrow break in the foliage, leading to a patch of muddy shore beyond. As she dragged herself out of the water, and up on the slippery bank, she noticed several rather large animal footprints in the mud. They were curious, three-toed footprints, with each toe ending in a large claw...

She bent to examine them more closely, and then she felt the earth vibrating, trembling beneath her hands. A large shadow fell over her and she looked up in astonishment at the leathery, pale underbelly of an enormous animal. She was too weak to react, even to raise her head.

The last thing she saw was a huge leathery foot landing beside her, shushing in the mud, and a soft snorting sound. And then suddenly, abruptly, exhaustion overtook her, and Sarah Harding collapsed, and fell onto her back. Her eyes rolled up into her head, and she lost consciousness.

Dodgson

A few yards up from the shore of the river, Lewis Dodgson climbed into the custom-made jeep Wrangler and slammed the door shut. Beside him in the passenger seat, Howard King was wringing his hands. He said, "How could you have done that to her?"

"Done what?" George Baselton said, from the back seat.

Dodgson did not reply. He turned the key in the ignition. The engine rumbled to life. He popped the four-wheel drive into gear and headed up the hill into the jungle, away from the boat at the shore.

"How could you?" King said again, agitated. "I mean, Jesus."

"What happened was an accident," Dodgson said.

"An accident? An accident?"

"That's right, an accident," Dodgson said calmly. "She fell overboard."

"I didn't see anything," Baselton said.

King was shaking his head. "Jesus, what if somebody comes to investigate and - "

"What if they do?" Dodgson said, interrupting him. "We were in rough seas, she was standing at the bow, a big wave hit us and she was washed overboard. She couldn't swim very well. We circled and looked for her, but there was no hope. A very unfortunate accident. So what are you concerned about?"

"What am I concerned about?"

"Yes, Howard. Exactly what the fuck are you concerned about?"

"I saw it, for Christ's sake - "

"No, you didn't," Dodgson said.

"I didn't see anything," Baselton said. "I was down below, the whole time."

"That's fine for you," Howard King said. "But what if there's an investigation?"

The Jeep bounced up the dirt track, moving deeper into the jungle. "There won't be," Dodgson said. "She left Africa in a hurry, and she didn't tell anybody where she was going."

"How do you know?" King whined.

"Because she told me, Howard. That's how I know. Now get the map out and stop moaning. You knew the deal when you joined me."

"I didn't know you were going to kill somebody, for Christ's sake."

"Howard," Dodgson said, with a sigh. "Nothing's going to happen. Get the map out."

"How do you know?" King said.

"Because I know what I'm doing," Dodgson said. "That's why. Unlike Malcolm and Thorne, who are somewhere on this island, screwing around, doing fuck knows what in this damned jungle."

Mention of the others caused a new worry. Fretting, King said, "Maybe we'll run into them...."

"No, Howard, we won't. They'll never even know we're here. We're only going to be on this island for four hours, remember? Land at one. Back on the boat by five. Back at the port by seven. Back in San Francisco by midnight. Bang. Done. Finito. And finally, after all these years, I'll have what I should have had long ago."

"Dinosaur embryos," Baselton said.

"Embryos?" King asked, surprised.

"Oh, I'm not interested in embryos any more," Dodgson said. "Years ago, I tried to get frozen embryos, but there's no reason to bother with embryos now. I want fertilized eggs. And in four hours, I'll have them from every species on this island."

"How can you do that in four hours?"

"Because I already know the precise location of every dinosaur breeding site on the island. The map, Howard."

King opened the map. It was a large topographical chart of the island, two feet by three feet, showing terrain elevations in blue contours. At several places in lowland valleys, there were dense red concentric circles. In some places, clusters of circles. "What's this?" King said.

"Why don't you read what it says," Dodgson said.

King turned the map, and looked at the legend. "'Sigma data Landsat/Nordstat mixed spectra VSFR/FASLR/IFFVR.' And then a bunch of numbers. No, wait. Dates."

"Correct," Dodgson said. "Dates."

"Pass dates? This is a summary chart, combining data from several satellite passes?"

"Correct."

King frowned. "And it looks like...visible spectrum, and false aparture radar, and...what?"

"Infrared. Broadband thermal VR." Dodgson smiled. "I did all this in about two hours. Downloaded all the satellite data summarized it, and had the answers I wanted."

"I get it," King said. "These red circles are infrared signatures!"

"Yes," Dodgson said. "Big animals leave big signatures. I got all the satellite flybys over this island for the last few years, and mapped the location of heat sources. And the locations overlapped from pass to pass, which is what makes these red concentric marks. Meaning that the animals tend to be located in these particular places. Why?" He turned to King. "Because these are the nesting sites."

"Yes. They must be," Baselton said.

"Maybe that's where they eat," King said.

Dodgson shook his head irritably. "Obviously, those circles can't be feeding sites."

"Why not?"

"Because these animals average twenty tons apiece, that's why. You get a herd of twenty-ton dinos, and you're talking a combined biomass of more than half a million pounds moving through the forest. That many big animals are going to eat a lot of plant matter in the course of a day. And the only way they can do that is by moving. Right?"

"I guess..."

"You guess? Look around you, Howard. Do you see any denuded sections of forest? No, you don't. They eat a few leaves from the trees, and move on. Trust me, these animals have to move to eat. But what they don't move is their nesting sites. So these red circles must be nesting sites." He glanced at the map. "And unless I'm wrong, the first of the nests is just over this rise, and down the hill on the other side."

The Jeep fishtailed in a patch of mud, and ground forward, lurching up the hill.

Mating Calls

Richard Levine stood in the high hide, staring at the herds through binoculars. Malcolm had gone back to the trailer with the others, leaving Levine alone. In fact, Levine was relieved to have him gone. Levine was quite content to make observations on these extraordinary animals, and he was aware that Malcolm did not share his boundless enthusiasm. Indeed, Malcolm always seemed to have other considerations on his mind. And Malcolm was notably impatient with the act of observation - he wanted to analyze the data, but he did not want to collect it.

Of course, among scientists, that represented a well-known difference in personality. Physics was a perfect example. The experimentalists and the theorists lived in utterly different worlds, passing papers back and forth but sharing little else in common. It was almost as if they were in different disciplines.

And for Levine and Malcolm, the difference in their approach had surfaced early, back in the Santa Fe days. Both men were interested in extinction, but Malcolm approached the subject broadly, from a purely mathematical standpoint. His detachment, his inexorable formulas, had fascinated Levine, and the two men began an informal exchange over frequent lunches: Levine taught Malcolm paleontology; Malcolm taught Levine nonlinear mathematics. They began to draw some tentative conclusions which both found exciting. But they also began to disagree. More than once they were asked to leave the restaurant; then they would go out into the heat of Guadelupe Street, and walk back toward the river, still shouting at each other, while approaching tourists hurried to the other side of the street.

In the end, their differences came down to personalities. Malcolm considered Levine pedantic and fussy, preoccupied with petty details. Levine never saw the big picture. He never looked at the consequences of his actions. For his own part, Levine did not hesitate to call Malcolm imperious and detached, indifferent to details.

"God is in the details," Levine once reminded him.

"Maybe your God," Malcolm shot back. "Not mine. Mine is in the process."

Standing in the high hide, Levine thought that answer was exactly what you would expect from a mathematician. Levine was quite satisfied that details were everything, at least in biology, and that the most common failing of his biological colleagues was insufficient attention to detail.

For himself, Levine lived for the details, and he could not ever let them go. Like the animal that had attacked him with Diego. Levine thought of it often, turning it over and over again, reliving the events. Because there was something troubling, some impression that he could not get right.

The animal had attacked quickly, and he had sensed it was a basic theropod form-hind legs, stiff tail, large skull, the usual-but in the brief flash in which he had seen the creature, there seemed to be a peculiarity around the orbits, which made him think of Carnotaurus sastrei. From the Gorro Frigo formation in Argentina. And in addition, the skin was extremely unusual, it seemed to be a sort of bright mottled green, but there was something about it...

He shrugged. The troubling idea hung in the back of his mind, but he couldn't get to it. He 'ust couldn't get it.

Reluctantly, Levine turned his attention to the parasaur herd, browsing by the river, alongside the apatosaurs. He listened as the parasaurs made their distinctive, low trumpeting sounds. Levine noticed that most often the parasaurs made a sound of short duration, a kind of rumbling honk. Sometimes, several animals made this sound at once, or very nearly overlapping; so it seemed to be an audible way of indicating to the herd where all the members were. Then there was a much longer, more dramatic trumpeting call. This sound was made infrequently, and only by the two largest animals in the herd, which raised their heads and trumpeted loud and long. But what did the sound mean?

Standing there in the hot sun, Levine decided to perform a little experiment. He cupped his hands around his mouth, and imitated the parasaur's trumpeting cry. It wasn't a very good imitation, but immediately the lead parasaur looked up, turning its head this way and that. And it gave a low cry, answering Levine.

Levine gave a second call.

Again, the parasaur answered.

Levine was pleased by this response, and made an entry in his notebook. But when he looked up again, he was surprised to see that the parasaur herd was drifting away from the apatosaurs. They collected together, formed a single line, and began to walk directly toward the high hide.

Levine started to sweat.

What had he done? In some bizarre corner of his mind, he wondered if he had imitated a mating cry. That was all he needed, to attract a randy dinosaur. Who knew how these animals behaved in mating? With growing anxiety, he watched them march forward. Probably, he should call Malcolm, and ask his advice. But as he thought about it, he realized that by imitating that cry he had interfered with the environment, introduced a new variable. He had done exactly what he had told Thorne he did not intend to do. It was thoughtless, of course. And surely not very important in the scheme of things. But Malcolm was certain to give him hell about it.

Levine lowered his binoculars and stared. A deep trumpeting sound reverberated through the air, so loud it hurt his ears. The ground began to shake, making the high hide sway back and forth precariously.

My God, he thought. They're coming right for me. He bent over, and with fumbling fingers, searched his backpack for the radio.

Problems of Evolution

In the trailer, Thorne took the rehydrated meals out of the microwave, and passed the plates around the little table. Everyone unwrapped them, and began to cat. Malcolm poked his fork into the food. "What is this stuff?"

"Herb-baked chicken breast," Thorne said.

Malcolm took a bite, and shook his head. "Isn't technology wonderful?" he said. "They manage to make it taste just like cardboard."

Malcolm looked at the two kids seated opposite him, who were eating energetically. Kelly glanced up at him, and gestured with her fork at the books strapped into a shelf beside the table. "One thing I don't understand."

"Only one?" Malcolm said.

"All this business about evolution," she said. "Darwin wrote his book a long time ago, right?"

"Darwin published the Origin of Species in 1859," Malcolm said.

"And by now, everybody believes it, isn't that right?"

"I think it's fair to say that every scientist in the world agrees that evolution is a feature of life on earth," Malcolm said. "And that we are descended from animal ancestors. Yes."

"Okay," Kelly said. "So, what's the big deal now?"

Malcolm smiled. "The big deal," he said, "is that everybody agrees evolution occurs, but nobody understands how it works. There are big problems with the theory. And more and more scientists are admitting it."

Malcolm pushed his plate away. "You have to track the theory," he said, "over a couple of hundred years. Start with Baron Georges Cuvier: the most famous anatomist in the world in his day, living in the intellectual center of the world, Paris. Around 1800, people began digging up old bones, and Cuvier realized that they belonged to animals no longer found on earth. That was a problem, because back in 1800, everybody believed that all the animal species ever created were still alive. The idea seemed reasonable because the earth was thought to be only a few thousand years old. And because God, who had created all the animals, would never let any of his creations become extinct. So extinction was agreed to be impossible. Cuvier agonized over these dug-up bones, but he finally concluded that God or no God, many animals had become extinct - as a result, he thought, of worldwide catastrophes, like Noah's flood."

"Okay..."

"So Cuvier reluctantly came to believe in extinction," Malcolm said, "but he never accepted evolution. In Cuvier's mind, evolution didn't occur. Some animals died and some survived, but none evolved. In his view, animals didn't change. Then along came Darwin, who said that animals did evolve, and that the dug-up bones were actually the extinct predecessors of living animals. The implications of Darwin's idea upset lots of people. They didn't like to think of God's creations changing, and they didn't like to think of monkeys in their family trees. It was embarrassing and offensive. The debate was fierce. But Darwin amassed a tremendous amount of factual data - he had made an overwhelming case. So gradually his idea of evolution was accepted by scientists, and by the world at large. But the question remained: how does evolution happen? For that, Darwin didn't have a good answer."

" Natural selection," Arby said.

"Yes, that was Darwin's explanation. The environment exerts pressure which favors certain animals, and they breed more often in subsequent generations, and that's how evolution occurs. But as many people realized, natural selection isn't really an explanation. It's just a definition: if an animal succeeds, it must have been selected for. But what in the animal is favored? And how does natural selection actually operate? Darwin had no idea. And neither did anybody else for another fifty years."

"But it's genes," Kelly said.

"Okay," Malcolm said. "Fine. We come to the twentieth century. Mendel's work with plants is rediscovered. Fischer and Wright do population studies. Pretty soon we know genes control heredity-whatever genes are. Remember, through the first half of the century, all during World War I and World War II, nobody had any idea what a gene was. After Watson and Crick in 1953, we knew that genes were nucleotides arranged in a double helix. Great. And we knew about mutation. So by the late twentieth century, we have a theory of natural selection which says that mutations arise spontaneously in genes, that the environment favors the mutations that are beneficial, and out of this selection process evolution occurs. It's simple and straightforward. God is not at work. No higher organizing principle involved. In the end, evolution is just the result of a bunch of mutations that either Survive or die. Right?"

"Right," Arby said.

"But there are problems with that idea," Malcolm said. "First of all, there's a time problem. A single bacterium - the earliest form of life has two thousand enzymes. Scientists have estimated how long it would take to randomly assemble those enzymes from a primordial soup. Estimates run from forty billion years to one hundred billion years. But the earth is only four billion years old. So, chance alone seems too slow. Particularly since we know bacteria actually appeared only four hundred million years after the earth began. Life appeared very fast - which is why some scientists have decided life on earth must be of extraterrestrial origin. Although I think that's just evading the issue."

"Okay..."

"Second, there's the coordination problem. If you believe the current theory, then all the wonderful complexity of life is nothing but the accumulation of chance events - a bunch of genetic accidents strung together. Yet when we look closely at animals, it appears as if many elements must have evolved simultaneously. Take bats, which have echolocation-they navigate by sound. To do that, many things must evolve. Bats need a specialized apparatus to make sounds, they need specialized ears to hear echoes, they need specialized brains to interpret the sounds, and they need specialized bodies to dive and swoop and catch insects. If all these things don't evolve simultaneously, there's no advantage. And to imagine all these things happen purely by chance is like imagining that a tornado can hit a junkyard and assemble the Parts into a working 747 airplane. It's very hard to believe."

"Okay," Thorne said. "I agree."

"Next problem. Evolution doesn't always act like a blind force should. Certain environmental niches don't get filled. Certain plants don't get eaten. And certain animals don't evolve much. Sharks haven't changed for a hundred and sixty million years. Opossums haven't changed since dinosaurs became extinct, sixty-five million years ago. The environments for these animals have changed dramatically, but the animals have remained almost the same. Not exactly the same, but almost. In other words, it appears they haven't responded to their environment."

"Maybe they're still well adapted," Arby said.

"Maybe. Or maybe there's something else going on that we don't understand."

" Like what?"

"Like other rules that influence the outcome."

Thorne said, "Are you saying evolution is directed?"

"No," Malcolm said. "That's Creationism and it's wrong. Just plain wrong. But I am saying that natural selection acting on genes is probably not the whole story. It's too simple. Other forces are also at work. The hemoglobin molecule is a protein that is folded like a sandwich around a central iron atom that binds oxygen. Hemoglobin expands and contracts when it takes on and gives up oxygen-like a tiny molecular lung. Now, we know the sequence of amino acids that make up hemoglobin. But we don't know how to fold it. Fortunately, we don't need to know that, because if you make the molecule, it folds all by itself. It organizes itself. And it turns out, again and again, that living things seem to have a self-organizing quality. Proteins fold. Enzymes interact. Cells arrange themselves to form organs and the organs arrange themselves to form a coherent individual. Individuals organize themselves to make a population. And populations organize themselves to make a coherent biosphere. From complexity theory, we're starting to have a sense of how this self-organization may happen, and what it means. And it implies a major change in how we view evolution."

"But," Arby said, "in the end, evolution still must be the result of the environment acting on genes."

"I don't think it's enough, Arb," Malcolm said. "I think more is involved - I think there has to be more, even to explain how our own species arose."

"About three million years ago," Malcolm said, "some African apes that had been living in trees came down to the ground. There was nothing special about these apes. Their brains were small and they weren't especially smart. They didn't have claws or sharp teeth for weapons. They weren't particularly strong, or fast. They were certainly no match for a leopard. But because they were short, they started standing upright on their hind legs, to see over the tall African grass. That's how it began. just some ordinary apes, looking out over the grass.

"As time went on, the apes stood upright more and more of the time. That left their hands free to do things. Like all apes, they were tool-users. Chimps, for example, use twigs to fish for termites. That sort of thing. As time went on, our ape ancestors developed more complex tools. That stimulated their brains to grow in size and complexity. It began a spiral: more complex tools provoked more complex brains which provoked more complex tools. And our brains literally exploded, in evolutionary terms. Our brains more than doubled in size in about a million years. And that caused problems for us."

"Like what?"

"Like getting born, for one thing. Big brains can't pass through the birth canal - which means that both mother and child die in childbirth. That's no good. What's the evolutionary response? To make human infants born very early in development, when their brains are still small enough to pass through the pelvis. It's the marsupial solution - most of the growth occurs outside the mother's body. A human child's brain doubles during the first year of life. That's a good solution to the problem of birth, but it creates other problems. It means that human children will be helpless long after birth. The infants of many mammals can walk minutes after they're born. Others walk in a few days, or weeks. But human infants can't walk for a full year. They can't feed themselves for even longer. So one price of big brains was that our ancestors had to evolve new, stable social organizations to permit long-term child care, lasting many years, These big-brained, totally helpless children changed society. But that's not the most important consequence."

"No?"

"No. Being born in an immature state means that human infants have unformed brains. They don't arrive with a lot of built-in, instinctive behavior. Instinctively, a newborn infant can suck and grasp, but that's about all. Complex human behavior is not instinctive at all. So human societies had to develop education to train the brains of their children. To teach them how to act. Every human society expends tremendous time and energy teaching its children the right way to behave. You look at a simpler society, in the rain forest somewhere, and you find that every child is born into a network of adults responsible for helping to raise the child. Not only parents, but aunts and uncles and grandparents and tribal elders. Some teach the child to hunt or gather food or weave; some teach them about sex or war. But the responsibilities are clearly defined, and if a child does not have, say, a mother's brother's sister to do a specific teaching job, the people get together and appoint a substitute. Because raising children is, in a sense, the reason the society exists in the first place. It's the most important thing that happens, and it's the culmination of all the tools and language and social structure that has evolved. And eventually, a few million years later, we have kids using computers.

"Now, if this picture makes sense, where does natural selection act? Does it act on the body, enlarging the brain? Does it act on the developmental sequence, pushing the kids out early? Does it act on social behavior, provoking cooperation and child-caring? Or does it act everywhere all at once - on bodies, on development, and on social behavior?"

"Everywhere at once," Arby said.

"I think so," Malcolm said. "But there may also be parts of this story that happen automatically, the result of self-organization. For example, infants of all species have a characteristic appearance. Big eyes, big heads, small faces, uncoordinated movements. That's true of kids and puppies and baby birds. And it seems to provoke adults of all species to act tenderly toward them. In a sense, you might say infant appearance seems to self-organize adult behavior. And in our case, a good thing, too."

Thorne said, "What does that have to do with dinosaur extinction?"

"Self-organizing principles can act for better or worse. Just as self-organization can coordinate change, it can also lead a population into decline, and cause it to lose its edge. On this island, my hope is we'll see self-organizing adaptations in the behavior of real dinosaurs - and it'll tell us why they became extinct. In fact, I'm pretty sure we already know why the dinosaurs became extinct."

The radio clicked. "Bravo," Levine said, over the intercom. "I couldn't have put it better myself. But perhaps you better see what is happening out here. The parasaurs are doing something very interesting, Ian."

"What's that?"

"Come and look."

"Kids," Malcolm said, "you stay here and watch the monitors." He pressed the radio button. "Richard? We're on our way."

Parasaurs

Richard Levine gripped the railing of the high hide, and watched tensely. Directly ahead, coming into view over a low rise, he saw the magnificent head of a Parasaurolophus walkeri. The duck-billed hadrosaur's skull was three feet long, but it was made larger by a long horned crest that extended backward high in the air.

As the animal approached, Levine could see the green mottling on the head. He saw the long powerful neck, the heavy body with its light green underbelly. The parasaurolophus was twelve feet tall, and roughly the size of a large elephant. Its head was almost as high as the floor of the high hide. The animal moved steadily toward him, its footsteps thumping on the ground. Moments later, he saw a second head appear over the rise-then a third, and a fourth. The animals trumpeted, and walked in single file directly toward him.

Within moments, the lead animal was abreast of the hide. Levine held his breath as it passed. The animal stared at him, its large brown eye rolling to watch him. It licked its lips with a dark-purple tongue. The hide shook with its footsteps. And then it had passed, continuing on toward the jungle behind. Soon after, the second animal passed.

The third animal brushed against the structure, rocking it slightly. But the dinosaur did not seem to notice; it continued steadily on. So did the others. One by one, they disappeared, into the dense foliage behind the high hide. The earth ceased to vibrate. It was then that he saw the game trail, running past the high hide and into the jungle.

Levine sighed.

His body relaxed slowly. He picked up his binoculars and took a deep breath, calming himself His panic faded. He began to feel better.

And then he thought: What are they doing? Where are they going? Because, as he considered it, the behavior of the parasaurs seemed extremely strange. They had been in a defensive cluster while they fed, but in movement they had shifted to single file which broke the usual clumped herd pattern, and made every animal vulnerable to predation. Yet the behavior was clearly organized. Moving in single file must serve some purpose.

But what?

Now that they were within the jungle, the animals had begun making low trumpeting sounds of short duration. Again, he had the sense that this was some sort of vocalization to convey position. Perhaps for members to keep track of each other while they moved through the jungle, while they changed locations.

But why were they changing locations?

Where were they going? What were they doing?

He certainly couldn't tell here, standing up in the high hide. He hesitated, listening to them. Then, in a decisive moment, he swung his leg over the railing and climbed quickly down the scaffolding.

Heat

She felt heat, and wet. Something rough scraped along her face, like sandpaper. It happened again, this roughness on her cheek. Sarah Harding coughed. Something dripped on her neck. She smelled an odd, sweetish odor, like fermenting African beer. There was a deep hissing sound. Then the rough scraping again, starting at her neck, moving up her cheek.

Slowly, she opened her eyes and stared up into the face of a horse. The big, dull eye of the horse peered down at her, with soft eyelashes. The horse was licking her with its tongue. It was almost pleasant, she thought, almost reassuring. Lying on her back in the mud, with a horse -

It wasn't a horse.

The head was too narrow, she suddenly saw, the snout too tapered, the proportions all wrong. She turned to look and saw that it was a small head, leading to a surprisingly thick neck, and a heavy body -

She jumped up, scrambling to her knees. "Oh my God!"

Her sudden movement startled the big animal, which snorted in alarm, and moved slowly away. It walked a few steps down the muddy shore and then turned back, looking at her reproachfully.

But she could see it now: small head, thick neck, huge lumbering body, with a double row of pentagonal plates running along the crest of the back. A dragging tail, with spikes in it.

Harding blinked.

It couldn't be.

Confused and dazed, her brain fumbled for the name of this creature, and it came back to her, all the way from childhood.

Stegosaurus.

It was a God damn stegosaurus.

In her astonishment, her mind went back to the glaring white hospital room, when she had visited Ian Malcolm in his delirium, when he mumbled the names of several dinosaurs. She had always had her suspicions. But even now, confronted by a living stegosaur, her immediate reaction was that it must be some kind of a trick. Sarah squinted at the animal, looking for the seam in the costume, the mechanical joints beneath the skin. But the skin was seamless, and the animal moved in an integrated, organic way. The eyes blinked again, slowly. Then the stegosaurus turned away from her, moved to the water's edge, and lapped it with its large rough tongue.

The tongue was dark blue.

How could that be? Dark blue from venous blood? Was it coldblooded? No. This animal moved much too smoothly; it had the assurance - and indifference - of a warm-blooded creature. Lizards and reptiles always seemed to be paying attention to the temperature of their surroundings. This creature didn't behave that way at all. It stood in the shade, and lapped up the cold water, indifferent to it all.

She looked down at her shirt, saw the foamy spittle running down from her neck. It had drooled on her. She touched it with her fingers. It was warm.

It was warm-blooded, all right.

A stegosaurus.

She stared.

The stegosaurus's skin had a pebbled texture, but it was not scaly, like a reptile's. It was more like the skin of a rhino, she thought. Or of a warthog. Except it was entirely hairless, without the bristles of a pig.

The stegosaurus moved slowly. It had a peaceful, rather stupid air. And it probably was stupid, she thought, looking again at the head. The braincase was much smaller than that of a horse. Very small for the body weight.

She got to her feet, and groaned. Her body ached. Every limb and muscle was sore. Her legs trembled. She took a breath.