Unnatural Selection (26 page)

“You didn’t want gloves, did you?” asked Merrill, who was partial to doing his dissecting bare-handed. “When I’m working with tissue, I find the sense of touch in my bare hands extremely sensitive,” he had once told Gideon-who much preferred gloves, and for exactly the same reason.

“Gloves?” Gideon said now, as if they were the furthest thought from his mind. “No, of course not.” With luck, he wouldn’t have to touch anything.

Many pathologists had their dieners do the gross cutting-the Y-incision, and the ear-to-ear over-the-top-of-the-head incision to get at the skull-but not Merrill, of course. He preferred to do it all himself, so once Rajiv had placed a support block under the back of Joey’s head and turned on the hanging microphone to record their observations, the diener stepped away from the table, awaiting further instructions.

“Well, let’s see what we have,” Merrill said happily. Gideon half expected him to rub his hands together, but with his arms remaining folded, he peered long and hard at Joey’s head. “What do you think?”

Until that moment, Gideon hadn’t looked directly at Joey’s face, but now he did. It helped, he found, that Joey didn’t look much like Joey anymore. In addition to the puffiness and distortion that went with death from cranial blunt-force trauma, on his face had blossomed a pair of bilateral periorbital hematomas-spectacular, purplish, shiny black eyes, which were known in the trade as “raccoon eyes,” and for good reason. Huge and round, blackening both his upper and lower eyelids, swelling them closed, and as dark as stage makeup, they made it look as if he were wearing a strange, pale face mask with black holes cut out for the eyes. His hair, so colorless and fine to begin with, had been rinsed by Rajiv under the faucet at one end of the autopsy table and was still damp, so that it seemed limper and sadder than ever. High on the back of his head, about two inches up from the part of the scalp overlying what anthropologists called “lambda”-the Y-shaped juncture where the two parietals meet the occipital bone-a circular area three or four inches in diameter had been shaved, the better to show a gaping, star-shaped laceration where his scalp had split open.

“You’re the pathologist,” Gideon answered. “What do you think?”

“I think we’re looking at a pretty obvious case of blunt-force trauma to the posterior parietal region, which, of course, goes along with the injuries on the radiograph.” He added a few observations for the microphone and pressed gently against Joey’s cheeks and temples. “No indications of superficial damage around the eyes, and the craniofacial skeleton seems undamaged. I expect we’ll find that the orbital hematomas are not distinct injuries, but a result of the parietal trauma, the force having been transmitted by the brain.”

Gideon nodded. “Contrecoup.”

“Contrecoup,” Merrill agreed.

They were talking about one of the most intriguing and least understood aspects of damage to the human skull and brain: the distinction between coup and contrecoup injuries. Generally speaking, when a moving object hit a stationary head-a blow with a hammer, say-the injury to the brain was going to be directly under the impact point. Whack a man hard enough on the occipital bone at the back of the head, and it will almost always be the occipital lobe of the brain that gets pulped. That was a “coup” injury. But when things were reversed, when a moving head hit a stationary object-in a fall, for example-the brain injury was likely to be at the opposite pole of the brain. Let a man fall off a catwalk onto stone paving and land on that same, rearward occipital bone, for example, and it would be the frontal lobe of the brain that got mashed into red jelly: a “contrecoup” injury.

Why this should be had puzzled scientists for centuries. In 1766 the Royal Academy of Surgeons in Paris had offered a prize for a definitive explanation of contrecoup. They didn’t get one then, and they still didn’t have one that satisfied everybody. Gideon, no expert on the brain, was willing to accept the common theory that, in a fall, the skull is traveling faster than the brain that is cradled inside it, so that when the back of the head hits the ground the brain continues to move, subjecting it to a piling-up of impact forces at the front.

Whether that was really the way it worked or not, contrecoup injuries were a fact, and he agreed with Merrill that they were looking at one now.

“Well!” exclaimed Merrill, and now he really did rub his hands together. “Let’s get on with it!” He stuck out a hand, into which Rajiv slapped the scalpel that he had waiting. Gideon moved a discreet step back. Rajiv, who was already wearing surgical gloves, now pulled up the mask that had been loosely tied around his neck.

Merrill, maskless and gloveless-contrary to both forensic and hygienic protocol-was a quick, sure worker, with no wasted movement. One hand, on Joey’s forehead, steadied his head against the block, while the other placed the scalpel blade behind the left ear. A moment’s pause to align the blade to the path that was to be followed, and the scalpel was deftly whipped over the top of the head, well in front of the scalp wound, and around to the back of the other ear: the standard coronal mastoid incision to expose the skull. With Joey dead so long, there was very little blood, but all the same Gideon’s stomach contracted, almost as if he could feel the blade slicing through his own scalp. This was at least the twentieth autopsy at which he’d been present, and before them he’d dissected two corpses in gross anatomy in graduate school, yet it was always the same. Would he never get used to them?

Probably not, but at least he no longer scandalized the autopsy staff by throwing up in the nearest sink, which he’d done the first time, in the San Francisco city morgue, a place he’d never again had the nerve to show his face.

With the cut made, the scalp was now essentially divided into two flaps. The rear one was pulled back and the front one vigorously tugged forward and down over Joey’s face, hair side down, depersonalizing him yet a little more and helping Gideon toward thinking of what he was looking at simply as a cranium, and not as the cranium of the nice kid he’d had dinner with the night before last. The yellowish, blood-flecked skull, its delicate, meandering coronal and sagittal sutures faintly visible, was now exposed from the ears up, and Gideon, took a step toward it for a closer look, interest overcoming aversion.

“Depressed fracture,” he said.

“Yes, that’s a bit of a surprise, isn’t it?”

Gideon agreed that it was.

The thing was, coup and contrecoup injuries weren’t the only way in which stationary heads that got in the way of moving objects usually differed from moving heads that ran into stationary objects. The skull fracture that was most likely to result from a fall was what is known as a linear fracture-or in common parlance, a crack-that might be anything from a single, relatively straight fissure, to a spiral network, to a maze of large and small cracks that broke the skull into a hundred pieces. A depressed fracture, on the other hand, was one in which the bone directly under the impact point was partially or fully separated from the rest of the skull and driven in, toward the brain, much as a hammer, striking a block of foam, wouldn’t crack it in half, but would leave a sunken imprint of itself in the block. And, naturally enough, such “imprints” were most likely to be the result of blows with instruments-hammers, rocks, ash-trays, or anything else that came to hand in a murderous moment. One didn’t often find depressed fractures in falls onto flat surfaces.

One did, however, occasionally find them in falls directly onto edged or pointed objects.

Which is what Merrill concluded had happened. “His head must have struck something when he fell-something in addition to the paving, I mean. Would there have been any relatively small objects lying on the ground that his head might have hit? Rubble, rocks…?”

“I never did see the body in place, so I don’t know exactly where it landed,” Gideon said, “but yes, there was a lot of stuff lying around in the passageway: tools, construction material, pottery shards-”

“Well, there it is, then. It might have been anything: a rock, or

…” He paused, seeing Gideon’s scrutiny growing more intense. “I say! You can probably tell what it was from the shape of the wound, can’t you?” he asked eagerly. Merrill was something of a fan of Gideon’s, and had been from the first, having earlier read several of his papers in the Journal of Forensic Sciences and some of the more sensational articles in the general media about his work with skeletal remains. And so he tended to expect more than Gideon could always deliver.

“Well, sure, sometimes you can,” Gideon said, shaking his head, “but this one? I don’t know, it’s not a very well-defined imprint. Doesn’t look like anything to me at this point. No, I wasn’t looking at the depressed part, I was looking at the fracture pattern around it, trying to make out…”

His voice faded away, as it frequently did when he was studying bones or thinking about them. And there was something about this one that intrigued him. Sometimes the impacting force of whatever had caused the depressed fracture stressed the surrounding bone enough to create a network of radiating cracks around the depression, and that was what had apparently happened with Joey. The depressed fracture itself was an irregular disk of bone, no more than an inch across, and driven only a couple of millimeters below the rest of the skull, but it lay in a spider-web of cracks that ran jaggedly off in every direction, over much of the skullcap; the calvarium, as it was known. But unless he was mistaken…

Merrill had waited politely for a minute while Gideon stood unmoving, then for a second minute, and then exchanged a what-in-the-world-is-the-man-doing look with Rajiv, who shrugged.

Merrill coughed gently. “I say, Gideon, I’d certainly like to see what the situation is inside the braincase. I have to remove the calvarium anyway. Why don’t I just separate it and give it to you to examine at your leisure while I scoop out the brain, don’t you know?”

Pathologists, Gideon had noticed, were often in a hurry to get through the skeletal architecture, feeling that the “real” information was going to come from the internal organs and structures. Anthropologists, naturally enough, saw it the other way around.

In any case, Merrill’s offer suited Gideon just fine, and he was quick to agree. “You’ll make sure you don’t cut through any of the fracture lines, though?”

Merrill sighed and looked at him.

“Sorry, sorry,” Gideon mumbled.

Merrill held out his hand, into which Rajiv plunked most pathologists’ instrument of choice for skullcap removal: the Stryker saw, a vibrating saw with a small, semicircular blade that oscillated in a narrow arc of about twenty degrees. This limited action ensured that the blade would not cut through to any soft tissue, “such as,” Merrill had laughingly told him last time, “the pathologist’s hand.”

Gideon stepped back again, keeping well clear of the mist of bone tissue that the saw threw up as it circled the outside of the brain case, deeply scoring it. Once that was done, the saw was replaced by a small hammer and a narrow chisel, and then by a miniature pry bar, with which the top part of the skull was delicately pried away from the bottom. For the first time, Gideon closed his eyes, preferring not to watch. If he could have gotten away with it, he would have stuck his fingers in his ears as well, to avoid the sucking sound that came when the top of a skull was pulled off.

When he opened them, the rounded calvarium was on the table near Joey’s head, interior side down, and a concerned Merrill was frowning at him.

“Is anything wrong?”

“Uh, wrong? No, I just had something in my eye. It’s okay now.”

“Good. Would you like me to scrape the dura off, so you can have a look at the underside as well?”

The dura-the dura mater-was the outermost layer of the brain coverings-the meninges-and when the brain was removed it remained behind, stuck to the inside of the skull, making it impossible to see the skull’s interior surface.

“No, don’t,” Gideon said. “The calvarium’s really fragmented. I’m afraid the dura is all that’s holding it together. Anyway, it’s the outside I’m interested in.”

“Yes,” said Merrill, “mm, ha, look at that. Well, now. My word.” He was now as absorbed by Joey’s naked, glistening brain as Gideon had been by the skull, and why not, Gideon thought. Who was he to shake his head in amazement at someone who got enthusiastic about prodding with a finger-an ungloved finger-into a bloody brain? There were plenty of people who had a hard time seeing what it was about bones that so fascinated him.

“Wilson?” Gideon said. “Would there be someplace I could go with this?”

The question was met with raised eyebrows. “You don’t want to stay on for the rest of the autopsy? But we’ve hardly begun.”

“Oh, well, yes of course I do, I’d love to, but I only have a limited time, unfortunately. I do need to get back, so I’d better get on with looking over these fractures. And, really, I’m afraid I’ll be underfoot here. You don’t have that much room. And it would be better if I could examine it someplace quiet, maybe sitting down somewhere.”

It was overkill for a simple request, and Gideon feared that Merrill might read it for what it was-a lame attempt to get the hell out of the autopsy room-but all he could make out on the pathologist’s face were disappointment and surprise, both of which were manfully overcome.

“Certainly,” he said. “Rajiv, take Dr. Oliver to the specimen room. He can use the table there.”

Placing the calvarium on a towel, Rajiv led Gideon a couple of doors down the hall to a tiny room that stank even more of formaldehyde, and with good reason. The shelves that ran around three of the walls were loaded with specimen jars filled with various organs in cloudy formalin, some floating, some sunk to the bottom, some hanging on strings. But specimens in jars, well-separated as they were from their owners’ bodies, didn’t bother Gideon, and he had no trouble concentrating on the cracked, ivory-colored dome in front of him.