Chapter 1

    FIRST ITERATION

    [picture]

    "At the earliest drawings of the fractal curve, few clues to the underlying mathematical structre will be seen."

    IAN MALCOLM

    Almost Paradise

    Mike Bowman whistled cheerfully as he drove the Land Rover through the Cabo Blanco Biological Reserve, on the west coast of Costa Rica. It was a beautiful morning in July, and the road before him was spectacular: hugging the edge of a cliff, overlooking the jungle and the blue Pacific. According to the guidebooks, Cabo Blanco was unspoiled wilderness, almost a paradise. Seeing it now made Bowman feel as if the vacation was back on track.

    Bowman, a thirty-six-year-old real estate developer from Dallas, had come to Costa Rica with his wife and daughter for a two-week holiday. The trip had actually been his wife's idea; for weeks Ellen had filled his ear about the wonderful national parks of Costa Rica, and how good it would be for Tina to see them. Then, when they arrived, it turned out Ellen had an appointment to see a plastic surgeon in San Jose. That was the first Mike Bowman had heard about the excellent and inexpensive plastic surgery available in Costa Rica, and all the luxurious private clinics in San Jose.

    Of course they'd had a huge fight, Mike felt she'd lied to him, and she had. And he put his foot down about this plastic surgery business. Anyway, it was ridiculous, Ellen was only thirty, and she was a beautiful woman. Hell, she'd been Homecoming Queen her senior year at Rice, and that was not even ten years earlier. But Ellen tended to be insecure, and worried. And it seemed as if in recent years she had mostly worried about losing her looks.

    That, and everything else.

    The Land Rover bounced in a pothole, splashing mud. Seated beside him, Ellen said, "Mike, are you sure this is the right road? We haven't seen any other people for hours."

    "There was another car fifteen minutes ago," he reminded her. "Remember, the blue one?"

    "Going the other way . . ."

    "Darling, you wanted a deserted beach," he said, "and that's what you're going to get."

    Ellen shook her head doubtfully. "I hope you're right."

    "Yeah, Dad, I hope you're right," said Christina, from the back seat. She was eight years old.

    "Trust me, I'm right." He drove in silence a moment. "It's beautiful, isn't it? Look at that view. It's beautiful."

    "It's okay," Tina said.

    Ellen got out a compact and looked at herself in the mirror, pressing under her eyes. She sighed, and put the compact away.    The road began to descend, and Mike Bowman concentrated on driving. Suddenly a small black shape flashed across the road and Tina shrieked, "Look! Look!" Then it was gone, into the jungle.

    "What was it?" Ellen asked. "A monkey7"

    "Maybe a squirrel monkey," Bowman said.

    "Can I count it?" Tina said, taking her pencil out, She was keeping a list of all the animals she had seen on her trip, as a project for school.

    "I don't know," Mike said doubtfully.

    Tina consulted the pictures in the guidebook. "I don't think it was a squirrel monkey," she said. "I think it was just another howler." They had seen several howler monkeys already on their trip,

    "Hey," she said, more brightly. "According to this book, 'the beaches of Cabo Blanco are frequented by a variety of wildlife, including howler and white-faced monkeys, three-toed sloths, and coatimundis.' You think we'll see a three-toed sloth, Dad?"

    "I bet we do."

    "Really?"

    "Just look in the mirror."

    "Very funny, Dad."

    The road sloped downward through the jungle, toward the ocean.

    Mike Bowman felt like a hero when they finally reached the beach: a two-mile crescent of white sand, utterly deserted. He parked the Land Rover in the shade of the palm trees that fringed the beach, and got out the box lunches. Ellen changed into her bathing suit, saying, "Honestly, I don't know how I'm going to get this weight off."

    "You look great, hon." Actually, he felt that she was too thin, but he had learned not to mention that.

    Tina was already running down the beach.

    "Don't forget you need your sunscreen," Ellen called.

    "Later," Tina shouted, over her shoulder. "I'm going to see if there's a sloth.

    Ellen Bowman looked around at the beach, and the trees. "You think she's all right?"

    "Honey, there's nobody here for miles," Mike said.

    "What about snakes?"

    "Oh, for God's sake," Mike Bowman said. "There's no snakes on a beach."

    "Well, there might be. . . ."

    "Honey," he said firmly. "Snakes are cold-blooded. They're reptiles. They can't control their body temperature. It's ninety degrees on that sand. If a snake came out, it'd be cooked. Believe me. There's no snakes on the beach." He watched his daughter scampering down the beach, a dark spot on the white sand. "Let her go. Let her have a good time."

    He put his arm around his wife's waist.

    Tina ran until she was exhausted, and then she threw herself down on the sand and gleefully rolled to the water's edge. The ocean was warm, and there was hardly any surf at all. She sat for a while, catching her breath, and then she looked back toward her parents and the car, to see how far she had come.

    Her mother waved, beckoning her to return. Tina waved back cheerfully, pretending she didn't understand. Tina didn't want to put sunscreen on. And she didn't want to go back and hear her mother talk about losing weight. She wanted to stay right here, and maybe see a sloth.

    Tina had seen a sloth two days earlier at the zoo in San Jose. It looked like a Muppets character, and it seemed harmless. In any case, it couldn't move fast; she could easily outrun it.

    Now her mother was calling to her, and Tina decided to move out of the sun, back from the water, to the shade of the palm trees. In this part of the beach, the palm trees overhung a gnarled tangle of mangrove roots, which blocked any attempt to penetrate inland. Tina sat in the sand and kicked the dried mangrove leaves. She noticed many bird tracks in the sand. Costa Rica was famous for its birds. The guidebooks said there were three times as many birds in Costa Rica as in all of America and Canada.

    In the sand, some of the three-toed bird tracks were small, and so faint they could hardly be seen. Other tracks were large, and cut deeper in the sand. Tina was looking idly at the tracks when she heard a chirping, followed by a rustling in the mangrove thicket.

    Did sloths make a chirping sound? Tina didn't think so, but she wasn't sure. The chirping was probably some ocean bird. She waited quietly, not moving, hearing the rustling again, and finally she saw the source of the sounds, A few yards away, a lizard emerged from the mangrove roots and peered at her.

    Tina held her breath. A new animal for her list! The lizard stood up on its hind legs, balancing on its thick tail, and stared at her. Standing like that, it was almost a foot tall, dark green with brown stripes along its back. Its tiny front legs ended in little lizard fingers that wiggled in the air. The lizard cocked its head as it looked at her.

    Tina thought it was cute. Sort of like a big salamander. She raised her hand and wiggled her fingers back.

    The lizard wasn't frightened. It came toward her, walking upright on its hind legs. It was hardly bigger than a chicken, and like a chicken it bobbed its head as it walked. Tina thought it would make a wonderful pet.

    She noticed that the lizard left three-toed tracks that looked exactly like bird tracks. The lizard came closer to Tina. She kept her body still, not wanting to frighten the little animal. She was amazed that it would come so close, but she remembered that this was a national park. All the animals in the park would know that they were protected. This lizard was probably tame. Maybe it even expected her to give it some food. Unfortunately she didn't have any. Slowly, Tina extended her hand, palm open, to show she didn't have any food.

    The lizard paused, cocked his head, and chirped.

    "Sorry," Tina said. "I just don't have anything."

    And then, without warning, the lizard jumped up onto her outstretched hand. Tina could feel its little toes pinching the skin of her palm, and she felt the surprising weight of the animal's body pressing her arm down.

    And then the lizard scrambled up her arm, toward her face.

    "I just wish I could see her," Ellen Bowman said, squinting in the sunlight. "That's all. Just see her."

    "I'm sure she's fine," Mike said, picking through the box lunch packed by the hotel. There was unappetizing grilled chicken, and some kind of a meat-filled pastry. Not that Ellen would cat any of it.

    "You don't think she'd leave the beach?" Ellen said.

    "No, hon, I don't."

    "I feel so isolated here," Ellen said.

    "I thought that's what you wanted," Mike Bowman said.

    "I did."

    "Well, then, what's the problem?"

    "I just wish I could see her, is all," Ellen said.

    Then, from down the beach, carried by the wind, they heard their daughter's voice. She was screaming.

    Puntarenas

    "I think she is quite comfortable now," Dr. Cruz said, lowering the plastic flap of the oxygen tent around Tina as she slept. Mike Bowman sat beside the bed, close to his daughter. Mike thought Dr. Cruz was probably pretty capable; he spoke excellent English, the result of training at medical centers In London and Baltimore. Dr. Cruz radiated competence, and the Cl��nica Santa Mar��a, the modern hospital in Puntarenas, was spotless and efficient.

    But, even so, Mike Bowman felt nervous. There was no getting around the fact that his only daughter was desperately ill, and they were far from home.

    When Mike had first reached Tina, she was screaming hysterically. Her whole left arm was bloody, covered with a profusion of small bites, each the size of a thumbprint. And there were flecks of sticky foam on her arm, like a foamy saliva.

    He carried her back down the beach. Almost immediately her arm began to redden and swell. Mike would not soon forget the frantic drive back to civilization, the four-wheel-drive Land Rover slipping and sliding up the muddy track into the hills, while his daughter screamed in fear and pain, and her arm grew more bloated and red. Long before they reached the park boundaries, the swelling had spread to her neck, and then Tina began to have trouble breathing. . . .

    "She'll be all right now?" Ellen said, staring through the plastic oxygen tent.

    "I believe so," Dr. Cruz said. "I have given her another dose of steroids, and her breathing is much easier. And you can see the edema in her arm is greatly reduced."

    Mike Bowman said, "About those bites. . ."

    "We have no identification yet," the doctor said. "I myself haven't seen bites like that before. But you'll notice they are disappearing. It's already quite difficult to make them out. Fortunately I have taken photographs for reference. And I have washed her arm to collect some samples of the sticky saliva-one for analysis here, a second to send to the labs in San Jose, and the third we will keep frozen in case it is needed. Do you have the picture she made?"

    "Yes," Mike Bowman said. He handed the doctor the sketch that Tina had drawn, in response to questions from the admitting officials.

    "This is the animal that bit her?" Dr. Cruz said, looking at the picture.

    "Yes," Mike Bowman said. "She said it was a green lizard, the size of a chicken or a crow."

    "I don't know of such a lizard," the doctor said. "She has drawn it standing on its hind legs. . . ."

    "That's right," Mike Bowman said. "She said it walked on its hind legs."

    Dr. Cruz frowned. He stared at the picture a while longer. "I am not an expert. I've asked for Dr. Guitierrez to visit us here. He is a senior researcher at the Reserva Biol��gica de Carara, which is across the bay. Perhaps he can identify the animal for us."

    "Isn't there someone from Cabo Blanco?" Bowman asked. "That's where she was bitten."

    "Unfortunately not," Dr. Cruz said. "Cabo Blanco has no permanent staff, and no researcher has worked there for some time. You were probably the first people to walk on that beach in several months. But I am sure you will find Dr. Guitierrez to be knowledgeable."

    Dr. Guitierrez turned out to be a bearded man wearing khaki shorts and shirt. The surprise was that he was American. He was introduced to the Bowmans, saying in a soft Southern accent, "Mr. and Mrs. Bowman, how you doing, nice to meet you," and then explaining that he was a field biologist from Yale who had worked in Costa Rica for the last five years. Marty Guitierrez examined Tina thoroughly, lifting her arm gently, peering closely at each of the bites with a penlight, then measuring them with a small pocket ruler. After a while, Guitierrez stepped away, nodding to himself as if he had understood something. He then inspected the Polaroids, and asked several questions about the saliva, which Cruz told him was still being tested in the lab.

    Finally he turned to Mike Bowman and his wife, waiting tensely. "I think Tina's going to be fine. I just want to be clear about a few details," he said, making notes in a precise band. "Your daughter says she was bitten by a green lizard, approximately one foot high, which walked upright onto the beach from the mangrove swamp?"

    "That's right, yes."

    "And the lizard made some kind of a vocalization?"

    "Tina said it chirped, or squeaked."

    "Like a mouse, would you say?"

    "Yes."

    "Well, then," Dr. Guitierrez said, "I know this lizard." He explained that, of the six thousand species of lizards in the world, no more than a dozen species walked upright. Of those species, only four were found in Latin America. And judging by the coloration, the lizard could be only one of the four. "I am sure this lizard was a Basiliscus amoratus, a striped basilisk lizard, found here in Costa Rica and also in Honduras. Standing on their hind legs, they are sometimes as tall as a foot."

    "Are they poisonous?"

    "No, Mrs. Bowman. Not at all." Guitierrez explained that the swelling in Tina's arm was an allergic reaction. "According to the literature, fourteen percent of people are strongly allergic to reptiles," he said, "and your daughter seems to be one of them."

    "She was screaming, she said it was so painful."

    "Probably it was," Guitierrez said. "Reptile saliva contains serotonin, which causes tremendous pain." He turned to Cruz. "Her blood pressure came down with antihistamines?"

    "Yes," Cruz said. "Promptly."

    "Serotonin," Guitierrez said. "No question."

    Still, Ellen Bowman remained uneasy. "But why would a lizard bite her in the first place?"

    "Lizard bites are very common," Guitierrez said. "Animal handlers in zoos get bitten all the time. And just the other day I heard that a lizard had bitten an infant in her Crib in Amaloya, about sixty miles from where you were. So bites do occur. I'm not sure why your daughter had so many bites. What was she doing at the time?"

    "Nothing. She said she was sitting pretty still, because she didn't want to frighten it away."

    "Sitting pretty still," Guitierrez said, frowning. He shook his head. "Well. I don't think we can say exactly what happened. Wild animals are unpredictable."

    "And what about the foamy saliva on her arm?" Ellen said. "I keep thinking about rabies. . . ."

    "No, no," Dr. Guitierrez said. "A reptile can't carry rabies, Mrs. Bowman. Your daughter has suffered an allergic reaction to the bite of a basilisk lizard. Nothing more serious."

    Mike Bowman then showed Guitierrez the picture that Tina had drawn. Guitierrez nodded. "I would accept this as a picture of a basillsk lizard," he said. "A few details are wrong, of course. The neck is much too long, and she has drawn the hind legs with only three toes instead of five. The tall is too thick, and raised too high. But otherwise this is a perfectly serviceable lizard of the kind we are talking about."

    "But Tina specifically said the neck was long," Ellen Bowman insisted. "And she said there were three toes on the foot."

    "Tina's pretty observant," Mike Bowman said.

    "I'm sure she is," Guitierrez said, smiling. "But I still think your daughter was bitten by a common basilisk amoratus, and had a severe herpetological reaction. Normal time course with medication is twelve hours. She should be just fine in the morning."

    In the modern laboratory in the basement of the Cl��nica Santa Maria, word was received that Dr. Guitierrez had identified the animal that had bitten the American child as a harmless basilisk lizard. Immediately the analysis of the saliva was halted, even though a preliminary fractionation showed several extremely high molecular weight proteins of unknown biological activity. But the night technician was busy, and he placed the saliva samples on the holding shelf of the refrigerator.

    The next morning, the day clerk checked the holding shelf against the names of discharged patients. Seeing that BOWMAN, CHRISTINA L. was scheduled for discharge that morning, the clerk threw out the saliva samples. At the last moment, he noticed that one sample had the red tag which meant that it was to be forwarded to the university lab in San Jose. He retrieved the test tube from the wastebasket, and sent it on its way.

    "Go on. Say thank you to Dr. Cruz," Ellen Bowman said, and pushed Tina forward.

    "Thank you, Dr. Cruz," Tina said. "I feel much better now." She reached up and shook the doctor's band. Then she said, "You have a different shirt."

    For a moment Dr. Cruz looked perplexed; then he smiled. "That's right, Tina. When I work all night at the hospital, in the morning I change my shirt."

    "But not your tie?"

    "No. Just my shirt."

    Ellen Bowman said, "Mike told you she's observant."

    "She certainly is." Dr. Cruz smiled and shook the little girl's band gravely. "Enjoy the rest of your holiday in Costa Rica, Tina."

    "I will."

    The Bowman family had started to leave when Dr. Cruz said, "Ob, Tina, do you remember the lizard that bit you?"

    "Uh-huh."

    "You remember its feet?"

    "Uh-huh."

    "Did it have any toes?"

    "Yes."

    "How many toes did it have?"

    "Three," she said.

    "How do you know that?"

    "Because I looked," she said. "Anyway, all the birds on the beach made marks in the sand with three toes, like this." She held up her hand, middle three fingers spread wide. "And the lizard made those kind of marks in the sand, too."

    "The lizard made marks like a bird?"

    "Uh-huh," Tina said. "He walked like a bird, too. He jerked his head like this, up and down." She took a few steps, bobbing her head.

    After the Bowmans had departed, Dr. Cruz decided to report this conversation to Guitierrez, at the biological station.

    "I must admit the girl's story is puzzling," Guitierrez said. "I have been doing some checking myself. I am no longer certain she was bitten by a basilisk. Not certain at all."

    "Then what could it be?"

    "Well," Guitierrez said, "let's not speculate prematurely. By the way, have you heard of any other lizard bites at the hospital?"

    "No, why?"

    "Let me know, my friend, if you do."

    The Beach

    Marty Guitierrez sat on the beach and watched the afternoon sun fall lower in the sky, until it sparkled harshly on the water of the bay, and its rays reached beneath the palm trees, to where he sat among the mangroves, on the beach of Cabo Blanco. As best he could determine, he was sitting near the spot where the American girl had been, two days before.

    Although it was true enough, as he had told the Bowmans, that lizard bites were common, Guitierrez had never heard of a basilisk lizard biting anyone. And he had certainly never heard of anyone being hospitalized for a lizard bite. Then, too, the bite radius on Tina's arm appeared slightly too large for a basilisk. When he got back to the Carara station, he had checked the small research library there, but found no reference to basilisk lizard bites. Next he checked International BioSciences Services, a computer database in America, But he found no references to basilisk bites, or hospitalization for lizard bites.

    He then called the medical officer in Amaloya, who confirmed that a nine-day-old infant, sleeping in its crib, had been bitten on the foot by an animal the grandmother-the only person actually to see it-claimed was a lizard. Subsequently the foot had become swollen and the infant had nearly died. The grandmother described the lizard as green with brown stripes. It had bitten the child several times before the woman frightened it away.

    "Strange," Guitierrez had said.

    "No, like all the others," the medical officer replied, adding that he had heard of other biting incidents: A child in V��squez, the next village up the coast, had been bitten while sleeping. And another in Puerta Sotrero. All these incidents had occurred in the last two months. All had involved sleeping children and infants.

    Such a new and distinctive pattern led Guitierrez to suspect the presence of a previously unknown species of lizard. This was particularly likely to happen in Costa Rica. Only seventy-five miles wide at its narrowest point, the country was smaller than the state of Maine. Yet, within its limited space, Costa Rica had a remarkable diversity of biological habitats: seacoasts on both the Atlantic and the Pacific; four separate mountain ranges, including twelve-thousand-foot peaks and active volcanoes; rain forests, cloud forests, temperate zones, swampy marshes, and arid deserts. Such ecological diversity sustained an astonishing diversity of plant and animal life. Costa Rica had three times as many species of birds as all of North America. More than a thousand species of orchids. More than five thousand species of insects.

    New species were being discovered all the time at a pace that had increased in recent years, for a sad reason. Costa Rica was becoming deforested, and as jungle species lost their habitats, they moved to other areas, and sometimes changed behavior as well.

    So a new species was perfectly possible. But along with the excitement of a new species was the worrisome possibility of new diseases. Lizards carried viral diseases, including several that could be transmitted to man. The most serious was central saurian encephalitis, or CSE, which caused a form of sleeping sickness in human beings and horses. Guitierrez felt it was important to find this new lizard, if only to test it for disease.

    Sitting on the beach, he watched the sun drop lower, and sighed. Perhaps Tina Bowman had seen a new animal, and perhaps not. Certainly Guitierrez had not. Earlier that morning, he had taken the air pistol, loaded the clip with ligamine darts, and set out for the beach with high hopes. But the day was wasted. Soon he would have to begin the drive back up the hill from the beach; he did not want to drive that road in darkness.

    Guitierrez got to his feet and started back up the beach. Farther along, he saw the dark shape of a howler monkey, ambling along the edge of the mangrove swamp. Guitierrez moved away, stepping out toward the water. If there was one howler, there would probably be others in the trees overhead, arid howlers tended to urinate on intruders.

    But this particular howler monkey seemed to be alone, and walking slowly, and pausing frequently to sit on its haunches. The monkey had something in its mouth. As Guitierrez came closer, he saw it was eating a lizard. The tail and the hind legs drooped from the monkey's jaws. Even from a distance, Guitierrez could see the brown stripes against the green.

    Guitierrez dropped to the ground and aimed the pistol. The howler monkey, accustomed to living in a protected reserve, stared curiously. He did not run away, even when the first dart whined harmlessly past him. When the second dart struck deep in the thigh, the howler shrieked in anger and surprise, dropping the remains of its meal as it fled into the jungle.

    Guitierrez got to his feet and walked forward. He wasn't worried about the monkey; the tranquilizer dose was too small to give it anything but a few minutes of dizziness. Already he was thinking of what to do with his new find. Guitierrez himself would write the preliminary report, but the remains would have to be sent back to the United States for final positive identification, of course. To whom should he send it? The acknowledged expert was Edward H. Simpson, emeritus professor of zoology at Columbia University, in New York. An elegant older man with swept-back white hair, Simpson was the world's leading authority on lizard taxonomy. Probably, Marty thought, he would send his lizard to Dr. Simpson.

    New York

    Dr. Richard Stone, head of the Tropical Diseases Laboratory of Columbia University Medical Center, often remarked that the name conjured up a grander place than it actually was. In the early twentieth century, when the laboratory occupied the entire fourth floor of the Biomedical Research Building, crews of technicians worked to eliminate the scourges of yellow fever, malaria, and cholera. But medical successes-and research laboratories in Nairobi and S?o Paulo-had left the TDL a much less important place than it once was. Now a fraction of its former size, it employed only two full-time technicians, and they were primarily concerned with diagnosing illnesses of New Yorkers who had traveled abroad. The lab's comfortable routine was unprepared for what it received that morning.

    "Oh, very nice," the technician in the Tropical Diseases Laboratory said, as she read the customs label. "Partially masticated fragment of unidentified Costa Rican lizard." She wrinkled her nose. "This one's all yours, Dr. Stone."

    Richard Stone crossed the lab to inspect the new arrival. "Is this the material from Ed Simpson's lab?"

    "Yes," she said. "But I don't know why they'd send a lizard to us.

    "His secretary called," Stone said. "Simpson's on a field trip in Borneo for the summer, and because there's a question of communicable disease with this lizard, she asked our lab to take a took at it. Let's see what we've got."

    The white plastic cylinder was the size of a half-gallon milk container, it had locking metal latches and a screw top. It was labeled "International Biological Specimen Container" and plastered with stickers and warnings in four languages. The warnings were intended to keep the cylinder from being opened by suspicious customs officials.

    Apparently the warnings had worked; as Richard Stone swung the big light over, he could see the seals were still intact. Stone turned on the air handlers and pulled on plastic gloves and a face mask. After all, the lab had recently identified specimens contaminated with Venezuelan equine fever, Japanese B encephalitis, Kyasanur Forest virus, Langat virus, and Mayaro. Then he unscrewed the top.

    There was the hiss of escaping gas, and white smoke boiled out. The cylinder turned frosty cold. Inside he found a plastic zip-lock sandwich bag, containing something green. Stone spread a surgical drape on the table and shook out the contents of the bag. A piece of frozen flesh struck the table with a dull thud.

    "Huh," the technician said. "Looks eaten."

    "Yes, it does," Stone said. "What do they want with us?"

    The technician consulted the enclosed documents. "Lizard is biting local children. They have a question about identification of the species, and a concern about diseases transmitted from the bite." She produced a child's picture of a lizard, signed TINA at the top. "One of the kids drew a picture of the lizard."

    Stone glanced at the picture. "Obviously we can't verify the species," Stone said. "But we can check diseases easily enough, if we can get any blood out of this fragment. What are they calling this animal?"

    " 'Basiliscus amoratus with three-toed genetic anomaly,' " she said, reading.

    "Okay," Stone said. "Let's get started. While you're waiting for it to thaw, do an X-ray and take Polaroids for the record. Once we have blood, start running antibody sets until we get some matches. Let me know if there's a problem."

    Before lunchtime, the lab had its answer: the lizard blood showed no significant reactivity to any viral or bacterial antigen. They had run toxicity profiles as well, and they had found only one positive match: the blood was mildly reactive to the venom of the Indian king cobra. But such cross-reactivity was common among reptile species, and Dr. Stone did not think it noteworthy to include in the fax his technician sent to Dr. Martin Guitierrez that same evening.

    There was never any question about identifying the lizard; that would await the return of Dr. Simpson. He was not due back for several weeks, and his secretary asked if the TDL would please store the lizard fragment in the meantime. Dr. Stone put it back in the zip-lock bag and stuck it in the freezer.

    Martin Guitierrez read the fax from the Columbia Medical Center/Tropical Diseases Laboratory. It was brief: -

    SUBJECT: Basiliscus amoratus with genetic anomaly

          (forwarded from Dr. Simpson's office)

    MATERIALS: posterior segment, ? partially eaten animal

     PROCEDURES PERFORMED. X-ray, Microscopic, immunological RTX

    for viral, parasitic, bacterial disease.

    FINDINGS: No histologic or immunologic evidence for any communicable disease in man in this Basiliscus amoratus sample.

    (signed)

    Richard A. Stone, M.D., director

    Guitierrez made two assumptions based on the memo. First, that his identification of the lizard as a basilisk had been confirmed by scientists at Columbia University. And second, that the absence of communicable disease meant the recent episodes of sporadic lizard bites implied no serious health hazards for Costa Rica. On the contrary, he felt his original views were correct: that a lizard species had been driven from the forest into a new habitat, and was coming into contact with village people. Guitierrez was certain that in a few more weeks the lizards would settle down and the biting episodes won end.

    The tropical rain fell in great drenching sheets, hammering the corrugated roof of the clinic in Bah��a Anasco. It was nearly midnight; power had been lost in the storm, and the midwife Elena Morales was working by flashlight when she heard a squeaking, chirping sound. Thinking that it was a rat, she quickly put a compress on the forehead of the mother and went into the next room to check on the newborn baby. As her hand touched the doorknob, she heard the chirping again, and she relaxed. Evidently it was just a bird, flying in the window to get out of the rain. Costa Ricans said that when a bird came to visit a newborn child, it brought good luck.

    Elena opened the door. The infant lay in a wicker bassinet, swaddled in a light blanket, only its face exposed. Around the rim of the bassinet, three dark-green lizards crouched like gargoyles. When they saw Elena, they cocked their heads and stared curiously at her, but did not flee. In the light of her flashlight Elena saw the blood dripping from their snouts. Softly chirping, one lizard bent down and, with a quick shake of its head, tore a ragged chunk of flesh from the baby.

    Elena rushed forward, screaming, and the lizards fled into the darkness. But long before she reached the bassinet, she could see what had happened to the infant's face, and she knew the child must be dead. The lizards scattered into the rainy night, chirping and squealing, leaving behind only bloody three-toed tracks, like birds.

    The Shape of the Data

    Later, when she was calmer, Elena Morales decided not to report the lizard attack. Despite the horror she had seen, she began to worry that she might be criticized for leaving the baby unguarded. So she told the mother that the baby had asphyxiated, and she reported the death on the forms she sent to San Jose as SIDS: sudden infant death syndrome. This was a syndrome of unexplained death among very young children; it was unremarkable, and her report went unchallenged.

    The university lab in San Jose that analyzed the saliva sample from Tina Bowman's arm made several remarkable discoveries. There was, as expected, a great deal of serotonin. But among the salivary proteins was a real monster: molecular mass of 1,980, one of the largest proteins known. Biological activity was still under study, but it seemed to be a neurotoxic poison related to cobra venom, although more primitive in structure.

    The lab also detected trace quantities of the gamma-amino metbionine hydrolase. Because this enzyme was a marker for genetic engineering, and not found in wild animals, technicians assumed it was a lab contaminant and did not report it when they called Dr, Cruz, the referring physician in Puntarenas.

    The lizard fragment rested in the freezer at Columbia University, awaiting the return of Dr. Simpson, who was not expected for at least a month. And so things might have remained, had not a technician named Alice Levin walked into the Tropical Diseases Laboratory, seen Tina Bowman's picture, and said, "Oh, whose kid drew the dinosaur?"

    "What?" Richard Stone said, turning slowly toward her.

    "The dinosaur. Isn't that what it is? My kid draws them all the time."

    "This is a lizard," Stone said. "From Costa Rica. Some girl down there drew a picture of it."

    "No," Alice Levin said, shaking her head. "Look at it. It's very clear. Big head, long neck, stands on its hind legs, thick tail. It's a dinosaur."

    "It can't be. It was only a foot tall."

    "So? There were little dinosaurs back then," Alice said. "Believe me, I know. I have two boys, I'm an expert. The smallest dinosaurs were under a foot. Teenysaurus or something, I don't know. Those names are impossible. You'll never learn those names if you're over the age of ten."

    "You don't understand," Richard Stone said. "This is a picture of a contemporary animal. They sent us a fragment of the animal. It's in the freezer now." Stone went and got it, and shook it out of the baggie.

    Alice Levin looked at the frozen piece of leg and tail, and shrugged. She didn't touch it. "I don't know," she said. "But that looks like a dinosaur to me."

    Stone shook his head. "Impossible."

    "Why?" Alice Levin said. "It could be a leftover or a remnant or whatever they call them."

    Stone continued to shake his head. Alice was uninformed; she was just a technician who worked in the bacteriology lab down the hall. And she had an active imagination. Stone remembered the time when she thought she was being followed by one of the surgical orderlies. . . .

    "You know," Alice Levin said, "if this is a dinosaur, Richard, it could be a big deal."

    "It's not a dinosaur."

    "Has anybody checked it.

    "No," Stone said.

    "Well, take it to the Museum of Natural History or something," Alice Levin said. "You really should."

    "I'd be embarrassed."

    "You want me to do it for you?" she said.

    "No," Richard Stone said. "I don't."

    "You're not going to do anything?"

    "Nothing at all." He put the baggie back in the freezer and slammed the door. "It's not a dinosaur, it's a lizard. And whatever it is, it can wait until Dr. Simpson gets back from Borneo to identify it. That's final, Alice. This lizard's not going anywhere."