Bones of the Earth

14. Intraspecific Communication

Lost Expedition Foothills: Mesozoic era. Cretaceous period. Senonian epoch. Maastrichtian age. 65 My B.C.E.

With dreamlike slowness, the great beasts browsed in the moonlight.

Oneirosaurus was the last and largest of the supersauropods. It was a late, final flowering of the Titanosaurinae, rare as rare, and a creature that all logic said properly belonged not in the late Cretaceous, but in the Jurassic, when giant sauropods were common. To see one was to refuse to believe it existed. To see five scattered across the river valley, as now, eating the jungle down to stubble, was a privilege Leyster knew he would cherish for the rest of his life.

Alone of all the creatures in the valley, Oneirosaurus never slept. It couldn’t afford to. It had to keep eating, moving its little head steadily, monotonously, from side to side until all the vegetation within reach was gone, and then taking a ponderous step or two forward to repeat the process. All day and all night it did this, just to keep alive.

It was not much of a life, but one they seemed dimly to enjoy. And it was one that could last for centuries. Leyster had heard rumors that individuals had been identified as being over five hundred years old.

Wonderful as those giant gray shadow-beasts were to look at, though, he knew that Lai-tsz hadn’t brought him out here for esthetic reasons. She was a pragmatist. Her mind just didn’t work that way.

“So what is it that you wanted me to see?” he asked.

“Not to see. To hear. To feel.”

“Then what—?”

“Shhh. Wait.”

She wrapped her arms protectively around her swollen belly, and stared out over the land. Prospect Bluff had a view second only to Barren Ridge—and no carnivores nested here. A touch of wind blew her hair forward, and she raised her chin slightly, as if to meet it.

Leyster found himself wishing he had the skill to paint in oils, so he could capture her as she was then, with the land a symphony of grays behind her, and the River Styx a gleam of silver meandering through it. There was something heroic about a pregnant woman. She carried all the hopes and fears of a new life within her body. Nobody could deny that she was engaged in serious business.

After a while, Lai-tsz made a face and said, “Little Turok is active tonight.”

“Have you decided on a name yet?”

“For the English name, I’m leaning toward Emily if it’s a girl, and Nathaniel if it’s a boy. For the Chinese—there! Listen!”

At first, Leyster heard nothing. He turned to Lai-tsz to say so, but something about her stance, the way she held her head, told him that she, at least could hear something. Whatever it was, though, had to be subtle and extremely easy to miss.

He willed himself perfectly still. He quieted all conscious thought.

He waited.

Slowly he became aware of a low, pervasive rumbling, like the inaudible undertones produced by the deepest pipes of a church organ. He felt more than heard it, in his chest and the pit of his stomach, a sound so deep into the bass that he had to wonder if he were fantasizing it.

“I…hear it, I think. Something. But what is it?”

Lai-tsz shivered in a kind of ecstasy. “Infrasound.”

“What?”

“I didn’t want to say anything before I got independent confirmation that there really is something there. They’re speaking to each other infrasonically—with sound waves of such low frequency that you and I can’t actually hear them.”

“My God,” Leyster said. “You mean they’re communicating with each other?”

“With each other, with oneirosaurs outside the valley—who knows? Infrasound can travel for miles. They could be speaking with kin beyond the horizon. Elephants use infrasound to communicate with each other over huge distances.”

“How did you discover this?”

“It’s Turok’s discovery, actually. The little floater grows very still whenever the oneirosaurs speak. Child-to-be would be bouncing around actively, and then suddenly stop, listening. After a while, I made the connection. Whenever Turok got still like that, there’d be an oneirosaur in sight. Either that, or else a tyrannosaur.”

“Tyrannosaurs, too?”

“Yes, I really do think so.”

Leyster laughed from sheer joy. “This is wonderful! You’ve made an incredible discovery.” He seized her hand and kissed it fervently. If it hadn’t been for young Turok, he would have picked her up and whirled her around in the air. “This is… it’s important!”

“Yes. I know,” Lai-tsz said complacently. Leyster understood that she was every bit as pleased as he was. She just didn’t like to show it.

For a time, they stared after the oneirosaurs determinedly eating their way up the valley, sharing the moment without speaking. The moon shone down hazily through a sky strewn with wisps of cloud. There would be rain in the morning, and re-growth would begin. When the lesser herbivores returned, there would be new food in plenty for them.

“It’s really quite marvelous,” Leyster said at last, “how everything fits together. The oneirosaurs level and fertilize the valley just at the right time to maximize growth. And then they move on, rather than staying and monopolizing the limited resources.”

“The herds should be returning soon.”

“Yes.”

“It’s funny, though, how the first animals to return from the migrations were the tyrannosaurs. Followed so closely by the oneirosaurs. It’s almost as if the one were leading the other.”

Leyster was silent for a moment. Then he said, “You don’t really believe that, though.”

“I don’t know. They both employ infrasound. It’s quite possible there’s interspecific as well as intraspecific communication going on. It’s something we really ought to look into.”

“How could we check? Could you build a device of some kind?”

“Oh, yeah, easily. We’ve got a couple of recorders, and all I’d have to do is speed up the playback to bring the ultrasonics up into audibility.”

“You’d have to take time away from trying to repair the time beacon, though.”

She threw him an odd look. “Oh, Richard,” she said, as if it were a negligible thing. “I thought you knew. I gave up on that a long time ago.”

To his amazement, he discovered that she was right. He knew she’d given up on their ever returning to their own time. He’d known it for months.

Finally, though, it was time to go home. They picked their way gingerly downslope and through the woods, guided by the fitful glimmer of one of their two remaining flashlights. Since Chuck had lost the third, two weeks ago, the flashlights had been put on the proscribed list of equipment that was never to leave the camp. But Lai-tsz’s condition superceded all rules. Leyster held the flashlight for her, walking half a step ahead and to the side, to make sure the way was safe.

“I miss Daljit and Jamal,” Lai-tsz said.

“They call every day.”

“It’s not the same.”

For the end of the rainy season, Daljit and Jamal had determined to go inland to meet the migrating herds partway home, make a count of their numbers, and possibly gain some insight into their behavior. They would have liked to follow the migrating herds out at the beginning of the season and back again in the spring, but everybody agreed there simply weren’t the resources yet to make that plan practical. So they’d compromised.

The Styx was tributary to the Eden River, which flowed through the Faraways (hardly mountains, but more than hills) at Water Gap. There, on an elevated spot above the migration trails Jamal and Daljit had set up their camp.

Two weeks they’d been waiting, while the herds didn’t come. There had been a flurry of excitement as the oneirosaurs passed through—fifty of them; they’d broken into smaller groups since—preceded by swift waves of tyrannosaurs. But since then, nothing.

The trees opened up onto Smoke Hollow. “Odd,” Leyster said. There was a light on in the long house. “People are still up?” They’d slipped away at sundown, explaining only that they’d be back late.

“Daljit and Jamal, remember? The evening satellite window opens late tonight. If they came up with something interesting this afternoon, this would be their first chance to share it.”

“You know, that satellite would be a lot more useful if it weren’t out of range so often. Why isn’t it in a geosynchrous orbit?”

“Well, two reasons, offhand. First, because it would take a lot more fuel to raise it to such a high orbit. Second, because a geosynchrous orbit is a lousy position for a mapping satellite.”

“There’s another thing. Why is a geosynchrous orbit so high? It would be a lot more convenient if it were lower.”

“Because it—oh, you’re teasing me!”

“It took you this long to figure that out?”

Mock-bickering, they entered the long house. Everyone squatted in a circle around Chuck, who was speaking on the phone.

Chuck looked up. His expression was uncharacteristically tense. “It’s Daljit,” he said. “Jamal’s been hurt.”

Luckily, Jamal’s injury was nothing worse than a broken leg. Unluckily, it left Daljit and him in no condition to return home without help. This at a time when their food supplies were running low and the migrating dinosaurs had flushed most of the small game from their immediate neighborhood.

After much discussion, it was decided that the largest rescue party they could manage was three people. After more discussion, it was agreed that those three should be Leyster, for his orienteering skill, Tamara, because she was the best hunter, and Chuck, because the other two wanted him.

“Why me?” Chuck asked cautiously. He’d been feeling a little insecure of late. Losing the flashlight had hit his self-esteem hard.

“Because you’ll keep our spirits up,” Tamara said. Leyster nodded gravely.

A small flush of pleasure spread over Chuck’s face.

In the morning, they packed their knapsacks, evenly dividing among them one poptent and three sleeping blankets, a coil of rope, knives, an axe, crocodile jerky and hadrosaur pemmican for food, a medicine kit, homebrew sun block and insect repellant, a Leica 8X20, a cell phone with solar recharger, map and compass, a friction lighter for starting fires, hooks and fishing line, a coil of snare wire, the butt end of a roll of duct tape in case anybody’s shoes started falling apart, sunglasses, rain gear and a change of clothing apiece, toothbrushes, a towel, two pens and a notebook, a pot for boiling water, and three water bottles. They went over the list three times to make sure they hadn’t left anything out, and then unfolded the map to plan their route.

“Originally, Daljit and Jamal traveled down to the mouth of the Styx, and then up the Eden River Valley,” Gillian said. “With the herds coming down the valley right now, that’s not advisable. You’re going to have cut cross-country.” She drew a straight line from Smoke Hollow to Water Gap with her finger. “That’s about twenty-five miles.”

“Piece of cake,” Chuck said.

“We ought to be able to do that,” Tamara said judiciously.

Leyster agreed. “How hard can it be?”

“It’s all up-and-down terrain, low hills, a few ridges. There ought to be streams, but since it’s mostly forested, the surveillance map doesn’t show them. The phone has a built-in positional system, so anytime the satellite’s above the horizon, you can locate yourself on the map.”

“Nobody here’s had a lot of experience in forested environments,” Nils said. “We’ve spent so much time in the river valley, we’ve gotten used to its ways. But the gods of the hills are not the gods of the valley. Keep that in mind, okay, guys?”

“No fear,” Leyster said. “Let’s go.”

Leyster took a compass reading from the top of Barren Ridge, and they started west-southwest. Each carried a spear in one hand and another tied to the back of their packs, all of them (except for Tamara’s Folly) with points of sharpened tyrannosaur ivory. In addition, Leyster carried the axe in a holster on his left hip. He was careful to keep the compass away from it.

The forest closed around them, and the shouted farewells of their friends faded away.

They walked.

For the first few hours they didn’t talk much, concentrating instead on making a good start. But the longer the silence lasted, the more time Leyster had to think. And the more he thought, the more he came up with speculations he wanted to know if the others shared.

Finally he said, “If tyrannosaurs and anatotitans do communicate with each other—and I’m not saying they do—what would they have to say to each other?”

“ ‘Surrender, Dorothy,’ ” Chuck said in a deep, rex-ish sort of voice. “ ‘I’ll get you and your little dog, too.’ ”

Tamara tried to choke back her laughter, and snorted instead. Then she said, “You remember last year, after the titanosaurs had eaten their way through the valley and were gone, how the Lord of the Valley stalked around the perimeter? And then, a couple of days later, the herds came pouring in?”

“Yeah?”

“Suppose he was staking out his territory, the way hawks do. He makes his claim to the valley and everything in it. Then maybe he’s actually calling the herds in. Telling them that the territory’s ready.”

“Why would they come, though?” asked Leyster, who’d been thinking along the same lines himself. “What’s in it for them?”

“A nice lush valley with plenty to eat, and a promise that if any other tyrannosaurs try to move in on them, the Lord will kick their butts. We’ve seen him drive away several bachelor rexes over the past year.”

“You’ve got to admit,” Chuck said. “It makes for an attractive package. Good food, good company, an absolute minimum of predation. If I were a hadro, I’d go for it in an instant.”

They were walking through a stretch of old-growth forest. The tree trunks were far apart from each other, and the floor was a soft and silent carpet of pine needles. They could talk quietly here, and without fear.

“As long as we’re speculating,” Tamara said, laying emphasis on that last word, “there could be any number of interspecific communication loops. Say the herds got too large for the carrying capacity of the valley, the rexes could split off smaller fragments of the herds and drive them away. We’ve seen behavior that looks very much like that.”

“How would they know to do that?” Leyster asked quickly.

“Infrasound again,” Tamara said. “If there’s too much of it around, too many trikes and titans gossiping back and forth, the rexes get irritable.”

“Only one thing can cure this headache,” Chuck said. “Scaring the crap out of a few herbivores.”

“Don’t forget,” Tamara said, “the behavior doesn’t have to be intentionally mediated. Ants engage in complex social behavior, and their brains are negligible, even by dinosaur standards.”

“Okay, but what’s in it for the tyrannosaur?”

“Easy prey. The herds are too large to keep together in tight, compact groups. They have to spread out to forage. Old Rexie can step in and bag one at his convenience.”

They were coming to the end of the old-growth forest. Ahead in the distance, the unvarying gloom brightened slightly, the diffuse effect of small shafts of light reaching through the canopy to the ground.

Leyster nodded. “I remember Dr. Salley gave a talk once in which she said that tyrannosaurs were farmers. I wonder if this is what she was talking about.”

“I was there too!” Chuck said. “You remember she said that mountains danced to the music of sauropods? I bet she was right about that one too.”

“Okay, now you’ve lost me.”

“Me too.”

“Hear me out. You know that continental drift isn’t silent, right? Those huge tectonic plates moving a couple of inches a year put out long, slow sound waves—infrasound. Now, if two oneirosaurs can hear each other a hundred miles apart, why can’t they hear the sound of the mountains moving and the plates shifting? And if they do, then there’s a mechanism for their migration. They can use those sounds to guide themselves into the interior and back again every year.

“But that’s not all! It would explain why all the non-avian dinosaurs died out at the K-T. There have been studies modeling the effects of the Chicxulub impactor and it would have struck the Earth like a gong! The infrasonic reverberations would have echoed back and forth for years.”

“So?” Tamara asked.

“So, during a time of enormous environmental stress, the major dinosaurs would have been deaf. Unable to migrate. Unable to communicate with each other. They, and everything reliant upon them, would have been at an incredible disadvantage. Imagine if ants suddenly lost the ability to cooperate socially! That’s where the dinosaurs would be.”

There was a moment’s silence. Then Tamara said, “Chuck, you’ve outdone yourself.”

“It’s inspired lunacy,” Leyster agreed. Chuck looked crestfallen. “Right up there with continental drift, or the notion that birds might be descended from dinosaurs.” Chuck brightened. “But it’s also right up there with Eric Van Danniken and Lamarckian genetics. Until we’ve tested it out, it’s just a nifty hypothesis, no more.”

“So let’s test it!”

“From here? I don’t see how. It hasn’t even happened yet. What kind of experiment could you…?” He lapsed into silence, considering the problem. If they could somehow jam the natural infrasonic emissions of the Earth, and then transmit a false signal, it would be possible to see if the migrating dinosaurs then went astray. But that would require equipment well beyond anything Lai-tsz could donkey together out of instrument chips and bailing wire. If they knew what part of the brain processed the infrasonics and then isolated it surgically—but that was as much a fantasy as the first notion. If they…

Leyster walked mechanically forward, spinning off idea after idea, until finally he came to the conclusion that the notion was untestable with the resources at hand. It was a problem they’d never be able to tackle, unless they were someday, against all odds, rescued.

He wondered if it was possible that they someday would go home again. It seemed unlikely. But not impossible. In which case, at that long-ago orientation lecture, Salley would have been simply feeding them their own speculations, repackaged as hers. He smiled sadly. That would be typical of her.

He looked up and saw that Tamara was staring at him. Chuck had taken over the lead, and was some twenty paces ahead of them. “I was just thinking about that lecture Dr. Salley gave,” he said.

“You’ve still got it for her, then?” she said quietly, so Chuck wouldn’t hear. He was not at all surprised by the ease with which she read deeper into his private thoughts than he himself had. She was a perceptive woman, and they, none of them, had a lot of secrets from one another anymore.

“No, that was just a notion I had once. I got over that one a long time ago.”

“Sure you did,” Tamara said. But affectionately. There was no sting in her words.

“Hey, look!” Chuck called. “There’s light ahead. A clearing!”

The clearing was filled with flowers, knee-high bushes, and a few musty-smelling sumacs. They were halfway across when they came too close to a toothbird nest. Chuck was in the lead, lustily singing “Waltzing Mathilda.” Leyster came second, and Tamara brought up the rear, spear in one hand and compass in the other.

Two birds burst out of the undergrowth.

Screaming, the male—they could tell by the bright orange slashes on its wings—dove at Tamara’s head. She flinched away, futilely slashing her spear in the air. It banked tightly, and dove at Chuck.

Meanwhile, the female ran straight at Leyster, wings out and claws extended. It climbed right up his pants and shirt. It happened so fast that the bird’s sharp-toothed beak was snapping at his face before he had time to react.

“Geddoff!” he yelled.

Toothbirds were enantiornithiforms the size of crows. Having an angry one on his chest was terrifying.

He swatted at the little horror, and it dug in its claws and jabbed at him with its beak.

“Get it off of me! Get it off!”

He was running, blindly, not caring where.

Chuck was running too, and stumbling, using his hat to try to ward off the creature. It flew in tight angry loops between him and Tamara, aiming always at their heads, their eyes. She plunged ignominiously through the bushes at the edge of the clearing, and disappeared.

Then Leyster too found himself immersed in the gloom of the deep woods. The archaeopterygian launched itself into the air. It flew angrily back to its young, screeching threats over its shoulder.

Leyster straightened warily. He looked around, and saw his friends shamefacedly approaching. Chuck shrugged, and grinned sheepishly.

“Well,” Tamara said. “We didn’t exactly cover ourselves with glory this time.”

“This one definitely doesn’t go in the autobiography,” Chuck agreed. “You okay?”

“Yeah, fine.” He’d been bitten on both of his hands and on one cheek. The bites ached like blazes. “Only, I think maybe we should go around this particular clearing.”

Toothbirds rarely nested alone. There might be dozens of nesting pairs further in.

“Let’s get those wounds bandaged up,” Tamara said, digging out her water bottle and eying a nasty-looking gash on Chuck’s forehead. “Before the smell of blood draws something really mean.”

Leyster nodded. From where they stood, they could still see the meadow, bright in the sun and framed by shadows, like a Victorian oil painting of the Garden of Eden, and like the Garden of Eden a place to which they could not return. How much did a toothbird weigh? Maybe nine ounces? It was a sobering thing to contemplate in a world containing predators weighing eight tons and more.

Though he said nothing, he was beginning to wonder if maybe this trek wasn’t going to be quite as easy as they had all confidently predicted.