by Eric Flint
"So what do you use? GPR? Seismics?"
"The short answer is yes." A.J. grinned. "Ground Penetrating Radar is just fine, for some things. But for others, some acoustic signals are good. Seismic shock is related to acoustics, of course, but I can induce different signal characteristics with acoustics than with a simple seismic signal. I can also sometimes get results with powerful magnetic fields. They react with the metals in the ground and bones, and bones are often packed with metal compared to their surroundings. I also use radiation detection-as I'm sure you know, sometimes fossils accumulate significant radioactives."
Helen nodded.
"There have been times I've used radiation directly in imaging, but that's not really practical in this setting, so I'll have to settle for whatever I get on the passives. Straight centimeter-scale radio waves on as high power as I can manage is another thing I'm going to try. While that wouldn't normally penetrate very far, a lot of your fossils here aren't all that far below the surface. I also try to use digital pulses where possible."
"Does that make them penetrate farther?" Helen asked. It didn't seem likely to her.
A.J. shook his head, smiling in acknowledgement of her doubtful tone. "Not directly, no. But what it does do is make it much, much easier for me to pick up the return signal from the noise, because I can listen for a specific pattern. I know what I'm looking for, in essence, and that really increases the chances of picking it up. Where the motes come in is in registering the returns from all different modes in thousands of closely related vectors, which the sensor net can coordinate and extract as precise survey points in spacetime. The motes construct their own ad hoc network and then derive their own relative positions with very high accuracy. Between time-of-flight, multiple triangulation, and a few other tricks like performing interference patterns, the network characterizes itself to within very small fractions of an inch. This means that the combined received signals are known to an extremely high degree of accuracy. That takes some processing time-that's what it's doing now, since I've stopped playing Tinkerbell.
"So once the network's fully characterized, I start setting off the signal pulses. I let the network know"-he tapped his glasses and the virtual control interface that only he could see-"exactly what signal I'm about to send, then trigger it. The net records all the responses it can, I hit it with another pulse; maybe change modes, it starts building up a rough picture. I examine it, see if I've got something coming up. Maybe I go back, do a few more GPR or radio shots, or try another acoustic signal, or shift frequencies. Eventually, I've got all the data I think will be useful. Then I can really go to town on this stuff; sensor fusion, bandpass filtering, synthetic aperture, Kalman and Weiner filters, all that kind of thing, plus some tricks of my own.
"With a handful of these motes and no special signal generators, I can use the ambient sound to locate and determine the number, direction, and general composition of your tents-without any of my dust motes actually touching the tents. Heck, with equipment twenty years older, I could send any two of you off to have a conversation, and not only locate you, but pick out your entire conversation, whispered, on the other side of a hill three hundred meters off. These motes have access to my own neural net code, expert systems, fuzzy logic structures, all sorts of stuff in the control unit and local heavy-duty processors, like in the main control unit here."
He patted another simple metallic box on his belt. "Give me powerful signal sources, and I'll guarantee to map out anything you want, above or below ground. And in this case, I'll even guarantee that you'll have enough detail to count teeth in a skull."
"Can you keep a record of how you produce the results?" Helen asked.
"Not only can I," A.J. answered, pacing out the area again as though measuring it, "it's pretty much part and parcel of the process-nice alliteration there, huh? I keep the raw data and track the sequence of filtering and analysis, all the way in. I have to-sometimes you don't get the best results and you need to experiment by taking out one step, moving it to another point in the sequence, and so on. It can make a big, big difference in the final results whether you filter first and then run an enhancement process, or enhance first and then filter, for instance. Pillage, then burn, so to speak."
He stopped, nodded to himself, then turned back towards the tents. "Well, it's getting pretty dark out here, but rather than waste time, I'll just get started."
Jackie and Helen held the lights as A.J. unpacked a number of devices with thick, rugged power leads.
As he did so, Helen studied him, a bit surreptitiously. Somewhat to her surprise, she was starting to find the man interesting.
In many ways, A.J. Baker was obviously a classic geek. Who else got that enthusiastic about dry-as-dust technical matter? But the muscles visible in his arms when he hefted the first case-the one that had nearly pulled Helen's shoulder out of its socket-made it clear that A.J. was in far better physical condition than the average geek.
On a personal level, the muscles impressed Helen even less than the flamboyantly awkward geeky mannerisms. But she found the combination rather intriguing. It reminded her of…
Well, herself, actually.
Since Helen didn't have that damnable male ego to deal with- the one that crucified every high school geek in existence-her own mannerisms weren't as awkward as A.J.'s. At least, she hoped not. But she could get just as enthusiastic when discussing paleontological issues, which were often literally as dry as dust. And on the few occasions when she ventured into public gymnasiums for a workout, she usually got admiring looks from all the men present and envious ones from the women. Even from women half her age.
From men half her age, she always got admiring looks. Ogles, often enough, to call things by their right name.
The thought of young men rallied her. Stop this, woman. He must be fifteen years younger than you are.
Thus fortified, Helen went back to studying A.J. from the perspective of an expert in one field watching another at his own. She did her best to ignore the treacherous little voice at the back of her mind, as it worked its way through simple mathematics.
Don't be silly. He's not as young as he looks. Can't be, not even in his cutting-edge field. He's got to be at least twenty-five or twenty-six. Maybe twenty-seven. Subtracted from thirty-eight, that is not fifteen years younger. It's only eleven. Maybe even less.
Shut up.
"Okay, here we got your GPR unit." A.J. held up a wide metallic antenna unit, followed by a cylindrical object that looked like a solid rod of metal but probably wasn't. "And this here's the impactor for seismic signals, some electromagnetic pulsers-keep metal and electronics that aren't shielded well away, folks-and my own shriekers. High-power ultrasonic pulsers."
The "shriekers" were strange things, looking a bit like large versions of the paddles found on a defibrillator unit, but ending with quivering blobs that looked like nothing so much as firm blue jello. They were labeled Kaled 1 and Kaled 2.
"What's that stuff?" Jackie asked, pointing to the blue blobs.
"Couplant gel. The attenuation of the signal through air is something fierce, so you try to use couplant to bring it more directly to the target. I wash the area off with a high-pressure water jet, then push the gel up against the rock. That increases the efficiency by many times. Even so, it'd be just plain useless without the Fairy Dust. You can immerse a sample in liquid and get good results, but in the field you just wouldn't get the penetration needed. With the sensor motes properly programmed and all over the place, and digitized pulses for signature return filtering, I can get results out of returns almost a hundred times weaker than I could with normal sensors."
"Anything else we can do to help?" Helen put in, seeing that he was now laying out his devices in a carefully planned order.
"Yeah," A.J. said. "Go away. Meaning no offense, just that once I start taking the readings the more people and objects in the area, the harder it's going to be for me to compensate for the signals. I have to sit dead stil
l while the data's being gathered, and even so I'll probably be having an effect that I'll notice later."
"No problem, we understand." Helen and Jackie started off. "Let us know when you're done."
"Sure thing," A.J. replied absently, already staring at a display on his VRD unit. "Your problems are just about over."
Eric Flint Ryk E. Spoor
Boundary
Chapter 4
"What the hell is that?"
A.J. was taken aback by the vehemence of Helen's question. "Hey, cool down. And why are you asking me? You're the paleontologist. I just image what's there."
Joe shook his head, then bent down to A.J. and spoke quietly. "Look, I don't know what you think you're doing, but cut out the joking and give us the real data."
A.J.'s eyes narrowed. "That is the real data. Top of the line. Imaged in three different spectra, multiple wavelengths, filtered, neural-net-processed, compared with known data for verisimilitude, and data-fused and analyzed out the wazoo. If I wasn't doing this for you and my own entertainment, you'd be paying about a hundred grand for this little job-over and above expenses. That is exactly, precisely, and inarguably what is down there."
"But that's just… impossible," Joe said defensively. He gestured at the projected image before them.
The computer-enhanced graphic showed the entire dig area in three-dimensional, mostly pastel false color. The rock still to be removed was present as an outline, an overlay of faintly gray glass. The fossils of the three raptors were clearly visible, the two newer ones now fully visible in their curved death poses. In addition, two more raptor skeletons were revealed, one on either side of the other three, making a rough three-quarter circle around the perimeter of the dig area. All five skeletons were fully articulated, possibly the finest specimens of Deinonychus ever uncovered- and all of them were sitting on a stippled red and purple layer that was the K-T boundary itself. White dots showed the position of hundreds of the strange pebbles, both around and past the raptor skeletons.
But it was what squatted ominously in the center of the image, in the middle of the rough circle delineated by the fossilized predators, that was the focus of such utter disbelief. It was large-close to four meters long, from end to end-and was as clearly defined as the other skeletons. The problem was…
"That's not even a skeleton," Helen said finally. "I'm not sure what to make of it."
"I thought it was like some kind of squid," A.J. said. "I know there was a lot of squiddage back then. Squids with shells, if I remember right. Ammonites, they were called?"
Joe frowned. "Well, we do have a sort of cephalopodic outline here." He sketched an elongated oval in the air. "Those could be tentacles, sort of. I only see three of them, though. And it looks almost like there are more at the rear."
"A lot shorter, though," Helen pointed out. "And much of the rest looks like it is a skeleton. Well, sort of. Weird though it is, that part here, near the longer, um, tentacles, looks like a skull to me, and it's attached to these other parts. But it's not an ammonite or any kind of shell, that's for damn sure. And what's the segmentation effect we have here? What are those things you're rendering in blue, A.J.? Look like layered armor plates or something."
A.J. shrugged. "Like I said, don't ask me what they are. But I can extract one for you, no problem."
He glanced into his VRD, mumbled some barely audible words, tapped out orders on an imaginary keyboard, and suddenly one of the "plates" glowed and seemed to spiral up and expand, filling a secondary window at the top of the image.
There were immediate startled exclamations from the three others in the tent.
"My god, Jackie. That's your mystery fossil!" Joe almost shouted.
If Helen had had any lingering thoughts that A.J. was playing some kind of practical joke, this eliminated them. None of them had mentioned Jackie's unique find to him, and A.J. certainly had never had a chance to see it.
Yet there was no doubt about it. The "shell" Jackie had found was now revealed to be one of many sequential components in what appeared to be some kind of arm.
"And the… tentacle on the right," Joe said, pointing. "There. It's shorter than the others. I'll bet that it lost part of the arm, maybe in a fight with the raptors, and so that part got weathered out."
"But what was it?" Helen demanded, returning to the main question. "How do those plates come into the picture? They're not armor-the attachment points make that clear. They're internal structures of some kind. But I don't see any ordinary bones or anything, so…"
"Maybe they are bones," Jackie suggested quietly.
Helen stopped short and looked more closely at the image. Her classes in reconstruction stood out more clearly now in her mind than ever before. She visualized the connections, the necessary methods for locomotion, the attachment points as related to the way the- arm plates?-were clearly meant to fit. She could see Joe's face going through the same steps, and that Joe was finding the conclusion hard to believe.
"A.J., can I use your interface?" she asked. "Or can you hook the simulation up to something I can access?"
"Your portable have standard wireless? Sure, hold on." A moment later, he said, "Okay, tell it to access WEIRDSIM. The interface should be pretty straightforward."
Helen saw the interface come up in front of her. Not that different from the one she used at the lab, actually. A.J. clearly understood the totality of his field, including user requirements. For several minutes there was mostly silence as Helen patched in her own reconstruction data, modified it, cursed softly as she realized she needed something unique, queried the Net for a formula that would describe what she wanted, added that in.
"Here goes. Take a look at this."
The general display flickered, and a long, slender window opened across the site display. The plates moved forward and backward in a motion similar to that of a telescope or old-style antenna, the individual parts extending to make a longer unit, then pulling back to retract the tentaclelike arm into a shorter, fatter configuration. It flexed and moved in a manner that was both familiar and subtly, disquietingly wrong. A stick-figure simulation showed the shorter, wider "tentacles" moving in a peculiar rhythm that pushed the weird thing along with surprising speed.
It certainly wasn't impossible, mechanically or biologically speaking. But it was clearly not a method of locomotion used by any form of life that Helen had ever seen or read about.
Joe's head lifted and he stared incredulously at the imaged fossil again. He then turned to Helen. She lifted her head, stared into his eyes, and then nodded slowly.
"My god. Helen, this is it! This is the biggest find in three centuries-in history, dammit!"
"And you and Jackie might want to get very far away before I finish this dig, too," Helen said softly.
"What the-? Oh."
Joe and Jackie looked at each other. Their expressions showed that they understood what Helen was saying.
A.J., however, was obviously in the dark. "Um, what's the problem? One second you're practically ready to start writing your Nobel Prize speeches. The next minute you're acting as if Jack the Ripper just came in."
Joe pointed at the image. "If Helen publishes a full report on that, it'll probably wreck her career."
"Well, not quite that," Helen said, shaking her head. "I've got tenure, after all, so I'd keep collecting a paycheck. But it would most likely get me relegated to the status of a crackpot. At least in the eyes of most of my colleagues."
"So screw 'em," A.J. snorted. "They don't believe you, too bad for them. It's right there in front of 'em!"
"A.J., that may work for you-your imaging work deals with real solid stuff that no one can argue with. But paleontologists are more in the position of detectives trying to figure out what happened with only a handful of clues."
Joe's tone of voice was that of a parent trying to explain the facts of life to a stubborn eight-year-old. Given that A.J. was, in point of fact, not more than a year or two younger than Joe, Helen found
it somewhat amusing.
But she could see that A.J. was beginning to bridle at the tone, so she intervened.
"Look, A.J., it's just a fact that paleontologists tend to be very conservative, in a scientific sense. Nor, by the way, do I say that critically. Joe's right, you know. We do have to work from mostly disconnected facts, just like detectives-and the fossil record is about as far removed as you can get from what anyone in their right mind would call a 'perfect crime scene.' Our data is hundreds of millions of year old, and fragmented to boot. There's so much gray area-so many different ways anything can be interpreted-that members of my profession generally look cross-eyed whenever somebody comes up with a sweeping proposition. Especially one that flies completely in the face of previous findings."
A.J. set his jaw. "So, what are you saying? You want to dump all this data and forget the dig?"
"Hell, no!" Helen said. She glanced at her two co-workers. "They're just worried. Mostly about me, and it's really sweet of you, Joe." Joe blushed.
"No, I just had to make sure they knew what might happen. You, A.J., I'm not worried about. Like Joe said, on your side no one will care what my interpretations of the data are, as long as the data you got is bona fide-and my excavation will prove that beyond any shadow of a doubt. But if I'm going to survive professionally, I'm going to have to be very, very careful about how I report this."
A.J. shrugged. Somehow he managed to make even that gesture a bit theatrical.
"Hey, as long as my pretty pictures don't go to waste, I'm happy. And if you end up in a controversy, it'll be free publicity for me. But it'd be a crying shame for them to be stupid enough to blackball you. I can tell a professional when I work with one."
He stretched. "Well, it's off to bed for me, and then back to the lab tomorrow. Thanks a lot for calling me in-this has been pretty challenging and interesting-and looks like it's going to be fun to watch the fireworks coming up." He grinned and headed off to the tent they'd set up for him.
"So," Joe said finally, after A.J.'s footsteps had faded away. "How are you going to approach it?"
