The Double Helix (Book 3) Read online

  Cruz squinted. A few yards off, Zane was pounding the ground with the blunt end of his square shovel.

  Aunt Marisol ran toward him. “Zane, careful there, we’re not chopping wood…”

  Cruz went back to work.

  Dig, scoop, drop.

  Dig, scoop, drop.

  “Speaking of adventure,” came the whisper in his ear. Cruz turned to look up at Professor Luben, who was also looking up. “Interesting outcrop, don’t you think?”

  Was it? Cruz followed his gaze up to the craggy gray rock at the top of the hill.

  “It’s the only rock shelter around for miles.” With a wink, his teacher picked a shovel off the pile, spun it to lay it against his shoulder, and headed across the field toward Team Earhart.

  Cruz kept staring up at the slope. He knew what Professor Luben was getting at. A natural shelter would be a good place for people to take refuge—ancient people. It could be fun to explore. Cruz looked at the hole at his feet. He sure wasn’t having much luck here. He’d take a quick break and be back before anyone knew he was gone.

  Adding a PANDA unit and a small trowel to his backpack, Cruz headed up the slope. As he hiked, the terrain became rockier. It took him a few tries to find a path between the tightly packed boulders. The hollow outcrop at the top of the hill wasn’t large, maybe 15 feet deep by 25 feet long by 5 feet high. The branches of overgrown bushes brushed the top of his head as he slipped under the flat rock of the roof. The opening of the shelter faced north, and since it was late afternoon, it was pretty dark inside. Tapping the shadow badge on his uniform, Cruz closed his eyes. He pictured a bioluminescent jellyfish pulsing through the ocean. When he opened his eyes again, his uniform was glowing. Yep. Better than any flashlight! And it was all thanks to Lumagine, Emmett’s mind-control fabric, and Fanchon’s skill at adapting the technology to their uniforms.

  It smelled like wet, warm dirt. Cruz crept to the back wall of the cave. He ran his hands along the cold, nubby surface. Cruz saw a pair of horizontal, dark red squiggles. Beside them was a crude stick figure drawn in the same red ocher. An ancient cave painting! They had just been reading about parietal art in anthropology class, too. Professor Luben and Aunt Marisol would love this! Cruz kept inching along, carefully following the massive stone wall from one corner to the other. Then he saw the handprint. They had learned about these types of prints in class. It looked to be a stenciled silhouette; that’s where a hand was placed on the wall and pigment was either dabbed along the edges or blown through a tube around the fingers, leaving behind a silhouette on the rock. Cruz wondered how old it was. Five thousand years? Ten? His PANDA unit would tell him.

  But first…

  Cruz couldn’t resist putting his palm on the ancient handprint. It was almost a perfect match. He was about to reach into his backpack for the PANDA when he felt a tremor. The rock was moving! It slid backward a few feet, then stopped. A space had opened up. The crevice was barely big enough for Cruz to squish a shoulder into. However, before he did, Cruz planted his feet. He didn’t want the dirt under him giving way. With his feet solid, his hands clamped firmly on to the cave wall, he leaned in. Cruz tipped his chin down. He saw only darkness.

  “Hello?” he called.

  His voice echoed back to him. “Helloooooooo?”

  A secret chamber! Cool! Cruz would have to get a photo before he headed back to tell—

  He felt a jolt, and suddenly, Cruz was falling…

  Skin was scraping rock.

  Falling…

  A point punctured his spine.

  Falling…

  End over end over end over end over end.

  Cruz hit the unforgiving ground with a bone-crunching thud. Pain shot through his shoulder. All the air knocked from his chest, he gasped for life. Cruz took several minutes to catch his breath. With a groan, he rolled up on his side, and came face-to-face with a skull.

  “Argggggh!” he cried, scooting backward until his spine smashed into stone.

  Heart thumping, lungs wheezing, Cruz wrapped his arms around his knees and pulled them into his chest. “Okay, don’t panic…Get a grip, Cruz.”

  By the glow of his uniform, Cruz saw that he was at the bottom of a stone cavern. Alone. Well, not completely alone. There was the skull. And, as he looked around, dozens more.

  He tipped his head back. He could not see daylight. Using the wall for balance, Cruz got to his feet. His body felt battered and beaten, as if he’d wiped out on the biggest, ugliest wave ever. Cruz limped around the perimeter of the wall, feeling for an opening, inlet, or tunnel that might lead out of this place.

  Nothing.

  Cruz touched his shoulder. His pack was gone! He searched the ground. It wasn’t there. It must have gotten snagged on a rock on the way down. Or maybe he had left it at the surface. He couldn’t remember. His phone and tablet were inside, so he couldn’t make a call out. Mell couldn’t help him, either. She was back on Orion getting a software upgrade. Cruz tapped his comm pin. “Cruz Coronado to Marisol Coronado.”

  No response.

  “Cruz Coronado to Emmett Lu.”

  Again, nothing.

  He tried every explorer, then Fanchon and Taryn, but it was no use. He had a feeling the signal wasn’t getting out.

  Cruz could hear water dripping. His shoulder throbbed. His head, too.

  He sagged against the wall. There was nothing to do now but wait for help to arrive. If it ever did. Cruz drifted off into a fitful sleep. He had a dream that someone pushed him and he was falling and falling and falling…

  Cruz woke up with a start. For one brief minute he thought he had dreamed everything, but he soon realized he was still at the bottom of the cavern. The cool dampness sent a chill through him. His stomach gurgled. His head felt foggy. His OS band indicated he had a concussion, along with a bruised shoulder, a broken right big toe, and a fever of 100.1. The glow from his bioluminescent uniform was beginning to fade. How long had he been here anyway?

  Cruz glanced at his OS band. It read 11/29, 12:09 a.m.

  Eight hours.

  Were they looking for him? Would they even know where to look?

  November 29. His birthday. Some present, huh?

  Cruz let out a tortured laugh. “Ha-ha!”

  It echoed back, taunting him. “Ha-haaaaa!”

  Stuck at the bottom of a shaft certainly wasn’t how Cruz had expected to spend his birthday. But he was alive. That was something worth celebrating, wasn’t it? Nebula had vowed to get rid of him before he turned 13. They had failed. Cruz looked around his dark prison of stone.

  Or had they?

  THE TRUTH BEHIND THE FICTION

  Explorers and archaeologists are history detectives, using clues left behind from ancient animals or civilizations to determine what our world was like thousands or even millions of years ago. Over time they have uncovered ruins of buildings, shards of pottery, fragments of bone, and fossils of extinct animals using simple tools and even their bare hands. Recent developments in technology have led to supercool advancements in archaeological research to allow finding often hidden or hard-to-reach spaces just waiting to be explored. What secrets are waiting to be uncovered? Check out these National Geographic explorers on the forefront of discovery.

  BETH SHAPIRO

  Evolutionary biologist Beth Shapiro may not have a fictional PANDA unit at her fingertips to be able to identify the origin, type, and age of human remains, fossils, and artifacts, but studying DNA has given her a remarkable window into the past. By retrieving DNA from ancient plants and animals, Shapiro is able to trace changes in diversity and populations over time. Science has typically explained the mass extinction of mammoths, mastodons, and saber-toothed cats 10,000 years ago as due to human overhunting or major changes in climate and vegetation. However, new studies of ancient DNA have shown that the true beginning of this huge extinction dates back tens of thousands of years to before the arrival of humans or the peak of the last ice age. The PANDA unit featured in The Double
Helix was inspired by Shapiro’s research. Imagine a world where you can scan any artifact for ancient DNA and pull up a realistic hologram of the source it came from!

  SARAH PARCAK

  How can satellites in outer space help us sleuth for civilizations far beneath Earth’s soil? As real-life pioneering space archaeologist Sarah Parcak could tell you, archaeologists can search for unknown sites all around the world by using high-tech images from space satellites. Experts can pinpoint potential dig locations that are covered by cities, forests, or layers of soil, bringing to the surface everything from pyramids to temples, from homes to entire cities, all from the comfort of their computer desk. While the human eye can only see light on the visible spectrum, satellites use different kinds of sensors to see infrared light, UV light, and microwaves. Microwaves are what allow scientists to see objects underground. This groundbreaking technology is being utilized not only to uncover important sites, but also to help combat looting. Cruz and his classmates examine several satellite maps and identify pits where someone may have stolen precious archaeological treasures. But you don’t have to be a student at Explorer Academy or an expert space archaeologist like Parcak to help. Parcak created GlobalXplorer°, an online tool that allows volunteers to see space satellite images, look for looting holes, and potentially find more incredible discoveries of their own!

  NORA SHAWKI

  Dr. Luben asks the explorers to analyze an Egyptian coffin and tell him what they can discover about the person who rested inside. By investigating the symbols on the coffin, they realize that Shesep​amunt​ayesher was a lady of the house. Without the coffin, the students wouldn’t be able to learn about her life. It’s up to archaeologists like Nora Shawki to help bring such incredible relics back from the past. Shawki has helped to excavate on dig sites all over Egypt, focusing currently on the Nile Delta. Here, she uses geophysical surveying, essentially taking a giant x-ray scan of a location, in order to understand where and how to dig. She says the Nile Delta “won’t exist in the next forty years,” because so many people are encroaching on the area, making it all the more urgent to locate settlements now. She believes that archaeology isn’t just about digging up golden sarcophagi and fancy jewelry of royals—it’s about learning what everyday people’s lives were like back in the day. “In history, anything is something,” Shawki says. “It’s like we are holding it between our hands, and we are the ones contributing to its interpretation.”

  MARINA ELLIOTT

  When Cruz gets separated from his group, he winds up with some newfound company: dozens of skulls! For many people this would be a terrifying discovery, but for biological anthropologist Marina Elliott, finding and investigating human remains is the rush of a lifetime. In 2013, famed paleoan​thropolo​gist Lee Berger asked Elliott and five other female scientists to join him in excavating Rising Star, a cave in South Africa. The “Underground Astronauts,” as they’d come to be nicknamed, had to venture through exceptionally tight passages, sometimes only eight inches wide, navigate through the dark, avoid a deadly ridge called Dragon’s Back, and slide down a 39-foot chute before they came to the resting place of one of the most astonishing discoveries in recent years: Homo naledi, a new species of human relative. And with a massive archaeology find under her belt, Elliott believes that “it’s just exciting to realize that the great age of exploration isn’t over with—that there still are places to explore and there are things to find.”

  LEE BERGER

  Lee Berger, lead paleoan​thropolog​ist of the team that discovered Homo naledi, has been digging into human origins in Africa for the past 30 years. The Homo naledi find was puzzling because of the mysterious way that the creatures appeared to be buried. There were no teeth marks on the bones to indicate that a predator dragged them deep into the cave. There were no other animal remains in the cave, so the entrance was probably sealed off. Moreover, some of the remains appeared to have had flesh on them when they were deposited in the cave. These clues suggested that the creatures were purposefully buried there. Scientists have long known that animals react to the death of their companions. Elephants, great apes, dolphins, horses, rabbits, cats, dogs, and some birds have all shown signs of grieving their lost loved ones. But ritual, purposeful burial is different, and was thought to be a humans-only activity. “We actually don’t have the whole story of human evolution. These discoveries are telling us that there’s a lot out there to be found,” Berger says. And indeed, this revolutionary find makes us question what we thought we knew about evolution and rethink our connection to our animal ancestors.

  To learn more about these topics and the passionate explorers who study them, check them out at the Explorer Academy website!

  exploreracademy.com

  Getting on all fours, Cruz began to crawl around the perimeter of the cave. There had to be a way out.

  “Or not.” He grimaced, gently rolling a skull out of his path.

  Ten minutes later, Cruz was huffing and about to take a break, when he realized his shoes were wet. If water was getting in, it had to come from somewhere. This could be a way out!

  The grotto was quickly beginning to fill. Cruz had to get to higher ground.

  Fortunately, Orion’s science tech lab chief, Fanchon Quills, had designed their uniforms to be waterproof, but Cruz had a feeling Fanchon hadn’t expected he would have to swim in the thing. In another few minutes, however, that’s exactly what he was going to have to do.

  Closing the collar of his uniform, Cruz felt something scrape the back of his neck. He reached behind him, his fingers closing around a metal tab. That’s right! Every explorer’s jacket was equipped with two critical survival items: a parachute, which wouldn’t help him here, and a flotation device, which most definitely would! Except Cruz wasn’t sure how to inflate the thing. He could almost hear his adviser, Taryn Secliff, say, You’d know what to do if you hadn’t glossed over the uniform instruction manual.

  “I know, Taryn, I know…” Cruz yanked open his belt and unzipped his jacket. Wrestling free of the sleeves, he whipped the coat inside out. He found a small plastic tab near the collar. It was engraved with a P—for “parachute,” no doubt. Okay, so where was the one to the float? Frantically, he went down the lining, searching for an F tab. He didn’t find one. Cruz moaned. “How in the world am I supposed to activate this dumb flotation device?”

  “Personal flotation device deployment confirmed.” The calm female voice startled him. It was Fanchon!

  “Cruz Coronado, please prepare for PFD deployment,” said Fanchon. Her instructions were coming from his OS band! Smart. He should have known that when all else failed, he could count on his OS band for help.

  Read a longer excerpt from The Star Dunes at exploreracademy.com.

  ACKNOWLEDGMENTS

  If you want to explore the world, read a book. If you want to explore yourself, write one. I’ve been extraordinarily fortunate to have some incredible people supporting my long journey of self-discovery: first and foremost, my parents, Dean and Shirley Strain, who saw that spark in me when I wrote my first ghost story as a kid and stoked the fire; my husband, Bill, who’s read every book I’ve ever written (even the ones about middle school girl power); my sister of the heart, Debbie Thoma, who has known me forever and loves me anyway; and my family, Jacques, Jennie, Lori Dru, Dean, Tammy, Austin, Trina, Bailey, and Carter. I am also lucky to have the most amazing team ever assembled in publishing: Becky Baines, Jennifer Rees, Jennifer Emmett, Erica Green, Eva Absher-Schantz, Scott Plumbe, Gareth Moore, Ruth Chamblee, Caitlin Holbrook, Holly Saunders, Ann Day, and so many others who helped breathe life into this project. This series would not have been possible without the real explorers of National Geographic. Thanks to Gemina Garland-Lewis, Nizar Ibrahim, Zoltan Takacs, Sarah Parcak, and all of the explorers who every day enlighten, inspire, and challenge us to follow their lead and make the world a better place. I’m grateful to PR gurus Karen Wadsworth and Tracey Mason Daniels of Media Masters and Virginia Anagno
s and her team at Goodman Media for their diligent efforts in spreading the word. Finally, thanks to my agent, Rosemary Stimola, who has so deftly steered me through the often treacherous waters of publishing for more than 15 years. She is a beacon of wisdom and kindness. Every writer should be so lucky.

  Cover illustration by Antonio Javier Caparo. Interior illustrations by Scott Plumbe unless otherwise noted below. All maps by National Geographic Maps.

  1: Antonio Javier Caparo; (double helix strands), Scott Plumbe; (watercolor), happykanppy/Shutterstock; (abstract techy curve background), Digital_Art/Shutterstock; (abstract techy round background), sadsadang/Shutterstock; 2, Babak Tafreshi/National Geographic Image Collection; 3, Hemis/Alamy Stock Photo; 4, Science History Images/Alamy Stock Photo; 5 (background photo), Anton Petrus/Shutterstock; 6, Ramillah/Shutterstock; 7 (background photo), Monik-a/Shutterstock; 8 (background photo), Truba7113/Shutterstock; 9, Chris Cook/Science Source; 10, Repina Valeriya/Shutterstock; 11, Mark Thiessen/National Geographic Image Collection; 12, Mathias Stiller/National Geographic Image Collection; 13 (inset), Beth Shapiro/National Geographic Image Collection; 14 (UP), Mark Thiessen/National Geographic Image Collection; 15 (LO), Sarah Parcak/National Geographic Image Collection; 16 (UP), Nora Shawki; 17 (LO), Mark Thiessen/National Geographic Image Collection; 18 (UP), Robert Clark/National Geographic Image Collection; 19 (LO), Robert Clark/National Geographic Image Collection; 20, Robert Clark/National Geographic Image Collection