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“Right.” Nell nodded.
“The specimen has a pair of large green-red-and-blue eyes with three optical hemispheres,” Otto narrated, and he tested the flexibility of the creature’s eyes with a poking index finger. “The eyes are mounted on short stalks that pivot or swivel inside a socket in its head. They also toggle in a socket at the end of the stalks, apparently, having a very ingenious mechanism.”
“I sure hope that thing’s dead,” Andy said.
Otto ignored him and wiggled the forelegs behind the head to see how they bent. “The large legs behind the head are very muscular and have spines at the end. They are fur-bearing, but the heavy spikelike spines are hairless, hard black exoskeleton or horn, and they seem to have a very sharp edge.”
“They look like praying mantis arms.”
“Yeah, that’s how they fold,” Otto agreed. “They may be able to act as shears or vises, too.”
“Or spears,” Nell suggested, shivering as she thought of what the others must have faced inside the crevasse. “The spigers speared the sand in front of them to back away from the water.”
Otto continued. “These mantislike subchelate arms are articulated to a bony ring under the skin, from which the neck musculature also extends. The next pair of limbs appears to be true legs. They resemble a quadruped’s forelegs…with one extra joint… and they seem to be attached to a broad central ring of bone that can be felt under the dermis and which forms a medial hump on the dorsal surface of the animal.”
“Those are eyes!” Nell exclaimed.
“Huh? Where?” Andy said.
“See, on top of that hump on its back, Otto?”
“Oh,” Andy said.
“There are eyes on the medial hump,” Otto confirmed, rinsing off more blue blood. “Which are similar to the eyes on the head.”
“Do you think it has a second set of optic lobes in its back?” Nell asked. “I mean, look, they’re image-forming eyes, not just light-intensity receptors.”
“Either there’s a brain under there or they have ridiculously long optic nerves,” Andy continued.
Otto continued his description. “There are three eyes on the central hump, reminiscent of the eyes on a jumping spider. One eye looks directly behind and one to each side. They each toggle inside a socket. I think you’re right, Nell. There could be some kind of ganglion structure under this hump. There’s a cranial cap on top of it similar to the one on the head of the animal.” As Andy winced, Otto tapped the brown chitinous cap on the hump between the eyes, testing to see if there was any reflex action left in the animal. There wasn’t.
Otto picked up a pair of dissection scissors and cut carefully along the mid-line of the cranial cap. He pulled each half apart with forceps. “Yep, it’s got a second brain.” He looked up at Nell. “This isn’t just some enlarged ganglion.”
“It’s got eyes in the back of its head,” Quentin said.
“And a head in the back of its eyes,” added Andy.
“See that pair of nerve cords running forward to the head?” Nell pointed at the close-up on the drop-down screen.
“Yeah, and here’s another pair that run toward the posterior of the animal. See there?” Quentin pointed. Two white twines of fine string stretched from the brain to the posterior of the animal like jumper cables.
“It may control the locomotion of its hind legs remotely with the second brain,” Nell theorized.
“I’ve never heard of such a thing,” Otto disagreed. “Not fucking possible!”
“Maybe it has specialized ganglia for speeding up its attack or evasive reflexes, or to help with digestion like some arthropods do,” Andy offered.
“Well, we won’t be able to determine that from a dissection.” Otto frowned. “We would have to do a detailed neurological study of live specimens. But we’ll see if we can follow the nerves later. Moving toward the posterior of the animal we see very powerful, kangaroo-like hind legs, with an extra joint where the tibia would be. These limbs are connected to a wide subcutaneous pelvic girdle that is ring-or tube-shaped like the other rings. The tail—”
“I don’t think that’s a tail,” Quentin said.
“It’s a leg,” Nell said.
Otto scowled.
“Pull it out from under the body,” Nell suggested.
“OK. The tail has a wide base. It is very stiff. It is long and broad, folding more than halfway under the animal to the chest area between the forelegs. The dorsal surface of the tail, which is the bottom when under the animal, is covered with ridged plates and spines in a geometric pattern.”
“Traction pads.” Nell indicated the bottom of the “tail.” “And cleats—like the bottom of a running shoe!”
“Whoa,” Quentin exclaimed. “It must rip that tail backwards under it to get air!”
“The taillike appendage appears to be a sort of ninth leg.” Otto shook his head in amazement. “This leg might be used to propel the animal higher or faster during leaps.”
“It kind of seems like an arthropod that turned into a mammal. Doesn’t it?”
“Yeah,” Andy said. “I was just thinking that. Spiders are furry crabs, or at least chelicerates.”
“This is no arthropod,” Otto scoffed. “With a mouth and jaws like that? And this is fur, not tarantula hair!”
“It’s bleeding again.” Nell pointed.
“The subject is leaking some light blue fluid that may be blood.”
“They must have hemocyanin. Copper-based blood, like marine arthropods. See? You can see it turning bluer as the liquid hits the air.”
“I’m extracting a blood specimen for analysis.” Otto took a hypodermic needle from a dissection kit affixed to the inside wall of the trough.
“Copper-based blood?” Nell looked at Andy.
“Maybe hemoglobin, too,” he said. “Some iron-based blood pigments are purple.”
“That’s blue,” Quentin said. “Are you color-blind?”
“No, I’m not color-blind!” Andy glared at Quentin.
“Could have fooled me.” Quentin was looking at Andy’s pink, yellow, and blue Hawaiian shirt.
Nell patted Quentin on the shoulder. “Let’s get a look inside this thing.”
“I’m now sealing the blood sample,” Otto narrated.
“Cut a little tissue sample, too, Otto,” Quentin told him. “That’ll make it easier to get a nucleic acid sample in case the blood doesn’t have any circulating cells.”
“Yeah, yeah.” Otto expelled the hypo full of blue liquid into a tube and capped it. Then he placed the sample into the specimen cradle, along with a small slice of tissue that he placed in a quarter-sized petri dish. After covering the petri dish, he pushed the cradle into the airlock. “OK, Quentin, let’s get a genetic analysis on this thing.”
Quentin sprayed the outside of the containers with isopropyl alcohol and then flooded the mini-airlock with yellow-green chlorine dioxide gas. When the gas was vacuumed out he retrieved the specimens through the airlock and handed them to the lab technicians, who immediately prepared blood agar cultures. One started grinding tissue samples in what resembled a test tube-sized blender. Attached to a high-speed tissue homogenizer, this glass chamber prevented the dispersal of any potentially harmful aerosol from the specimen into the air of the lab.
“We could be getting parasite DNA in the sample,” Nell told them. “Can you tell the difference?”
“Yep, we can distinguish samples,” one of the technicians answered.
Working in biological safety hoods along the other side of Section One, the technicians processed the samples, pipetting the blood and tissue and homogenizing them, adding reagents, mixing, centrifuging, decanting, heating, cooling, and finally pipetting the processed material onto other plates or into specimen tubes.
“My God, this is heaven, Otto,” Nell said, admiring the array of machines on the other side of the lab. “Do you know how many weeks it would have taken me to do this work as an undergrad at Caltech?”
/> “Yeah, this baby’s got more toys than a lab geek’s wet dream.” Quentin smiled proudly.
“I can still remember when I had to pour my own electrophoretic gels for molecular samples. Now it’s as easy as putting a piece of bread in a toaster.”
“Well, more like making cinnamon toast,” a technician remarked drily.
Nell laughed. “We even had to generate our own taq polymerase.”
“Give me a break,” Andy pleaded.
“I’m with you, Nell,” Quentin said. “You youngsters don’t appreciate how amazing these instruments are. God, Andy, when are you going to learn some molecular biology, dude? You’re more of a dinosaur than I am. PCR didn’t even exist when I was in college, but I saw where things were heading, and learned this stuff before I got left behind.”
“Well, somebody has to keep their feet in the mud,” Andy snapped, defensively.
“Bravo,” Nell said. “We need both right now, Andy—field naturalists and gene jocks. That machine Steve is using—hi, Steve!— is a Bioanalyzer. It will tell us in a few seconds how pure our RNA extractions are and how much RNA we got in each sample. It’s a microscopic electrophoresis unit and gel scanner that examines all the samples on those little chips that look like dominoes.
Each one of those dots is equivalent to a whole electrophoretic gel from the old days, when I was in my teens.” She pointed. “And when an RNA sample is put into the thermocycler right there, it gets reverse transcribed, making our cDNA library, and in the same tube it does the PCR. That amplifies the cDNA into thousands of copies so we can sequence the genes in this auto-sequencer right there, or test it in that micro-array machine over there.”
“You lost me at Parcheesi,” Andy grumbled.
“Dominoes,” Quentin teased.
“It’s actually pretty simple, Andy,” Nell told him. Her eyes glowed with excitement. “All living cells have RNA, which is a message transcribed from the genes in the DNA. So when we run the reactions backwards with an enzyme called reverse transcriptase, we make clones of the DNA—the cDNA—from the RNA! Then, to tell what these critters are related to, we can either run the cDNA on micro-array chips, which is really fast, sequence the DNA, or else isolate, clone, and sequence the actual genes from the cell’s DNA, which takes a little longer. You could do any of this yourself after a couple hours of training, Andy.”
“I learned the theory in my Bio courses,” he said. “I never used all these machines. I didn’t think normal people could work these things.”
“Who said you’re normal?” Quentin taunted.
“Andy,” Nell said, preempting his umbrage, “these guys in the lab coats wouldn’t know an arthropod from an anthropoid unless you handed them a gene sequence. No offense, guys.”
Otto cleared his throat. “Can we get back to the dissection while the gene jocks do their thing?”
“Carve that turkey!” Quentin commanded in agreement.
Nell swiveled on her stool and put her pencil to a fresh page on her sketchpad as Otto turned the animal onto its back and rinsed it again.
“The fur on the ventral surface of the specimen is light tan in color. The specimen appears to have an orifice on the central underbelly, probably for waste excretion, between the central legs.
Between the hind legs there appear to be sexual organs…both a penislike structure and what may be a vaginal opening.”
“Hermaphrodites?” Nell said.
“If so, there goes the arthropod theory,” Otto said. “No arthropods are hermaphroditic—”
“Right,” Quentin interrupted. “But many phyla of animals have at least a few groups that are hermaphrodites. Worms and snails, for example.”
“Barnacles are hermaphrodites,” Andy said. “They’re arthropods.”
“Barnacles are arthropods?” Otto asked.
“Yep.”
“Damn. That’s weird.”
“How do we know how long this ecosystem’s been isolated?” Nell intervened. “It’s at least theoretically possible that it’s had a very long time to evolve. I would say it’s probable, given what we are looking at, guys. I mean, come on.”
“Is this island radioactive?” Andy asked.
“Nope.” Quentin shook his head. “These aren’t just mutants.”
“Something like this must have diverged a long time ago, then,” Otto agreed. “Hell, that’s a given. But not from arthropods.”
“Well, how the hell else do you explain it, then, Otto?” Quentin was scowling again. “You think this thing came from Mars?”
“I don’t know where this thing came from, Quentin!” Otto retorted sharply. “And neither do you right now, OK?”
“Let’s take a look at the internal organs,” Nell interposed gently.
“OK.” Otto looked back up at the screen and lowered his shaking scalpel. “I’m starting the incision from the central orifice and cutting back toward the specimen’s tail.”
“God, I hope it’s dead,” Andy said.
“Stop saying that!” Otto snapped as he sliced through the thin but tough skin and laid open the animal’s belly.
“Hey!” someone shouted.
Everyone jumped and glared at the technician, who was pointing to the bubble window at the end of the lab.
But all they could see was the edge of the forest.
“Sorry! I could swear I just saw something looking at us out there. Big as a man, hanging right on that tree there. Fuck, it must have been a reflection or something. It had lots of arms and it looked like it was spying on us. Sorry. But I swear! It was there. Really.”
“Christ, Todd!” Quentin groaned. “Lay off the caffeine, OK?”
“I said I was sorry! But, Jesus, I saw it plain as day and never took my eyes off it and then it was just gone, man.”
Otto sighed and turned back to his work. “OK. Continuing the incision, there is an outer sheath or integument that is translucent grayish white, tinged blue. Making an incision through this sheath…it seems to be made of micro-hydrostatic tubes that release clear liquid when severed. Under this are distinct muscle bands running to various points throughout the body… they are especially dense at the bases of the appendages. And look at this here…we’ve got branching tracheal tubes extending into all the muscles.” He cleared his throat. “And each of them does connect with the integument.”
“It’s just like the gas exchange system of insects and spiders,” Andy intoned.
Otto nodded. “And, yes… there is a spiracle on the outer body surface for each trachea. The fur must have covered them.”
“Wow, so those trachea deliver the oxygen directly to the muscles from the outside,” Andy said. “If they’re that extensive it may be what allows such big animals to be so active.”
“Look how the spiracles line the sides of the body in neat rows.” Quentin pointed at the close-up on the screen over the specimen chamber. “And those rows extend right up along the legs…”
“Providing oxygen directly to the muscles.” Andy finished his sentence.
Otto cleared his throat again. “And, OK—immediately underneath the layers of muscles and tracheae are two green glands, each with a bladder that is light gray in color—”
“Looks like it has a urethra,” Andy said, thankful to see something familiar.
“Yes. These glands appear to empty at the joint at the base of the legs.” Otto attached retractors to hold open the incision. He suctioned some pooling, syrupy blood.
“Coxal glands, just like king crabs,” Andy sang.
“Spiders have coxal glands, too,” Quentin chimed.
“OK,” Otto said, irritated. “I’m now cutting anteriad from the central orifice. I’m exposing the rest of a wide, thin bone ring or cylinder that has an aperture in the ventral side. The spiked foreleglike appendages are attached to socketlike shoulders in each side of this bony structure.”
“Looks like a segment of a lobster tail.”
“But internal?” Otto scoffed. “An interna
l exoskeleton? It doesn’t make sense…”
“Does anything here make sense?” Nell said. “We’re segmented creatures, too, Otto, just a few steps removed from arthropods. Do we make sense?”
“It’s a lot of steps.” Otto shook his head stubbornly. “How could it molt?”
“Maybe the old shell dissolves or is absorbed internally as the new one hardens,” Nell suggested. “Surgeons use dissolving sutures that melt internally. Maybe they have a similar solution.”
“A lot of marine crustaceans eat their own shed shells to reuse the minerals,” Andy concurred.
“All right, noted,” Otto said. But he still didn’t sound as if he agreed with them. “Continuing the incision down the belly from the mantislike arms and the forelegs. OK, there’s a lot of fluid here! Suctioning that away…we see a series of six branching stomachs filled with what appear to be freshly eaten pieces of prey. Each stomach is segmented by a kind of bony grinding mechanism, like a bird’s gizzard—”
“Or a crustacean’s gastric mill,” Andy said.
“—which must masticate the food into finer consistency as it is passed along. Each of these stomachs is connected to a glandular mass—”
“That looks like a crustacean hepatopancreas,” said Andy.
“—and each also is connected to its own short intestine,” finished Otto.
“If any one of its digestive tracts is damaged it could shut it down and use the other five.” Nell had stopped sketching and was staring in fascination at the creature.
“Yeah, it would seem so.” Otto nodded, skeptically.
“All of the intestines empty into what appears to be a cloaca,” Quentin murmured.
“Crustaceans don’t have cloacae,” Otto said.
“Yeah,” Andy agreed. “Technically.”
“And look, the urethra from each kidney empties into the cloaca, too. And what’s that mass that looks like angel hair pasta there?” Quentin said.
“It looks like Malpighian tubules like insects and spiders have. Look how they all connect to the same region of the cloaca,” said Andy.
“That’s impossible, crustaceans don’t have Malpighian tubules,” said Quentin.
“Exactly,” Otto said.
“Both of you have to start thinking outside your comfort zone,” Nell said as she filled in a sketch. “These creatures would have had to have diverged from other crustaceans hundreds of millions of years ago, remember.”