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The sterile smell of bleach stung Lightbulb’s nose as she descended the slide to Test Tube’s new lab. Even stranger, the smell mixed with buttery, fresh-popped popcorn and stinging brass. Over the past few weeks, Test Tube had wasted no time drafting and building a new lab from scratch.
Despite that humongous workload, she still had time to mess with science and clone Cobs’ corpse. Go figure.
“Heyya Tubbette!” She called, cradling Baxter as she hit the floor. The crab shivered, and she placed him on her head and got to her feet. “Baxter’s here with me as his plus-one.”
“Oh! You’re early. Perfect, perfect.” She dissolved into muttering, and put down a bottle of… detergent?
“So what did you need him for?”
“I… actually just finished my genetic analyzer, and I needed to test it!” Walking across the lab, she stopped next to a microwave embedded in the wall, and gestured to a retro looking, frutiger aero-style computer. “Also, it’s been in the back of my mind for a while, nyeheh…”
“Genetics? Hold on,” Lightbulb placed Baxter on the counter and put her hands on her hips, “you’re not gonna like… mutate him with a spider or try to give him radioactive powers, are you?”
“Heh, hardly.” She snorted, “No, the radiation is kept securely downstairs. Rather than piercing his DNA with charged particles, I wanted to… well not destroy his genetic makeup, but instead analyze it!”
“Layman’s terms, Tubbette.”
She deadpanned, “I’m gonna do a DNA test.”
“Like… who’s the father?”
“Eh,” Making a so-so gesture, Test Tube reached for a remote on her desk and clicked it. A projector overhead turned on, showing a bunch of lines branching off and dividing to point at different shrimp, crabs, and lobsters. “More like who’s the father’s father’s father twenty million years ago. Really, I just want to see what kind of crab Baxter is.”
“Well no matter what kind he is, he knows he belongs.”
“Sure.”
They stood in awkward silence. Test Tube’s shoulders hitched.
“So…” Test Tube coughed, “Can I get that sample?”
“Hmmm… depends.” She scooped up Baxter and held him like a baby, “How invasive is this process.”
“I just need to nick the side of his claw.” Leaning forward, she tapped the small ridges jutting from Baxter’s shell.
Before Lightbulb could react, Test Tube whipped out a scalpel and flicked her wrist, slicing a bit off.
“Whoa, hey now!” She pulled Baxter away.
“Relax, it’s not painful.” Holding the tiny spine up to the light, Test Tube continued on without a second glance, flitting about the lab.
Near the bottle of detergent, a scale and a tidy row of bottles sat in a holder. Test Tube dropped the sample on the scale, and said aloud as she wrote, “zero point-two grams…”
Afterwards, she plopped it in one of the bottles, yoinking the detergent and measuring out a very specific amount.
Lightbulb drew closer to the counter and squinted her eyes to read the tiny numbers on the bottles. “What are you doing?”
“I’m destroying the cells.” Without missing a beat, she mixed something in with the detergent, then poured the mixture into the bottle.
“Why?”
“To…” She looked up, momentarily perplexed before falling back into her rhythm, “To get the DNA? Obviously. I can’t analyze the DNA if it’s all trapped in the nuclei.”
“That’s so sad.” Lightbulb rested her head in her arms, leaning fully on the counter. “You’re killing them.”
“It’s the small price to pay for science.” She muttered absently as she capped the bottle and shook it. After thirty seconds of shaking, Test Tube submerged it in a larger bottle of liquid, spun on her heel and shoved the sample into a little fridge, the door rattling as she slammed it.
“Since Baxter isn’t a part of MeLife,” Test Tube continued, “and has… earthly DNA, I’m really curious how he ended up in MePhone’s ecosystem. I hypothesize that his species might have influenced that.”
“It’s because he’s built different.” Lightbulb said, “The other crabs just couldn’t keep up.”
“Riiight.” Test Tube said dryly. “Or, you know, the artificial ecosystem could be more natural than we thought.”
She rapped her fingers along the mini-fridge, "aAong with Baxter’s DNA, I’ve gone and… acquired… some from other crabs in the area, excluding those that matched light shimmer DNA.”
“Light shimmer?” Lightbulb perked up, “Isn’t that the little egg guy you had?”
“Yes.”
Test Tube didn’t elaborate. After a few seconds, she patted the frutiger aero computer and continued like nothing happened, “So! After I sequence Baxter’s DNA, I’ll compare specific genes to see which crab or crab-like species he belongs to.”
“What are you implying there?” Her eyes narrowed, and Lightbulb slowly reached forward to grab Baxter.
“What?” She snapped, pulled from her explanation. “What do you mean?”
“‘Crab-like.’” Lightbulb guided Baxter’s claws to make it look like he was surrounding the word in air-quotes.
“Oh, like carcinization.”
“What?” She slammed her hands on the counter, “He has cancer!”
Test Tube paused. Her eyes traced Lightbulb’s form up and down, Baxter sitting in front of her. For a long, exasperated moment, Test Tube’s hand itched like she wanted to facepalm. Then a small reluctant smile sprung on her lips.
“No, that’s carcinogenesis. Carcinization is actually really cool. Basically, evolution leads to populations diverging from each other and growing so different that they become separate species. However!—The ‘crab’ build is just so good, that natural selection evolved species into crabs over five times. So Baxter might not even be an original true crab.”
“The stats are cracked—waitaminute.” Lightbulb lifted her head off the counter and covered Baxter’s ears, “You don’t say that in front of him! You’ll ruin his self-confidence.”
The remark bounced off Test Tube without affecting her this time, “Either way, sequencing Baxter’s DNA is a good record to have, and knowing what species he is will help us know how to treat him if he ever gets sick or hurt.”
“Okay—that’s something I can agree on.” She relented, letting go of Baxter.
A timer on the mini-fridge went off, and Test Tube spun to open it. She retrieved the bottle and held it up. Drifting dreamily to the top of the mixture was a thin mass of stringy white stuff, like millions of tiny, semi-translucent threads bunched together.
As Test Tube poured in a vial of clear liquid and left it alone, moving to turn on the sink and fill a tub with water, Lightbulb asked, “So… natural selection decided Baxter’s body is perfect for survival? Figures. They know good looks and personality when they see it.”
“Ehh… Natural selection is iffy phrasing at its best.” She shrugged, “It tricks our brains into thinking of natural selection as this… this…” Trailing off, she made vague gestures with her hands, “This invisible force. In reality, it doesn’t decide anything. It’s something that happens: Randomness and chance. Water doesn’t choose to evaporate. Atoms don’t want to have a full valence electron shell.”
Test Tube leaned over the sink and booped Baxter, “Nature doesn’t favor one species over another like two brands at the grocery, it just so happened that Baxter’s parents had traits that let them survive long enough to lay an egg.”
She turned off the tap and set a timer, scooping ice from the fridge into the bucket of water as Lightbulb stewed.
Instead of saying something profound, Lightbulb blurted, “That’s so… anticlimactic? Would make a horrible plot if you ask me. Way more boring than finding out a phone with alien energy designed every part of you and your personality.”
Test Tube froze like she had said something deeply thought-provoking, then shook her head. “If that’s how you wanna see it.”
The timer went off, and Test Tube plunged the DNA sample into the ice bath.
As she counted the seconds under her breath, Lightbulb said, “So if nature doesn't ‘decide’ anything, how does Baxter even exist? If nobody decides anything—like what to eat, then dinner never happens..”
“Oh, I see you.” A slightly deranged smile broke across Test Tube’s face, and she withdrew the bottle. Her hands dripping everywhere, she spun to stick it in a little rectangular machine-box. “There are five principles of natural selection. They’re basically how things happen. Randomness reigns supreme, but they abide by the rules of VISTA.”
After inputting a setting on the machine-box, Test Tube jabbed the whiteboard of the back wall, and scribbled the letters ‘V,’ ‘I,’ ‘S,’ ‘T,’ ‘A,’ in red expo marker.
“Vista?” Lightbulb repeated, “Like, the Spanish word? Hasta la vista?”
“Nnnope.” She popped. “It’s an acronym. The first letter stands for…” Getting on her tippy toes, she wrote after the ‘V,’ as she spoke, “V…ariation of genes. In Baxter’s case, the group of his crustacean species has a bunch of little differences. His friend from—from…”
“Crab college.” Lightbulb nodded sagely.
“Sure. Crab college. This friend might’ve had longer eye stalks than Baxter. Or another friend was more orange. These small variations are the fundamental base of evolution. The second letter stands for,” Test Tube finished the word, stepping down to check the DNA sample, “inheritance of genes. To oversimplify it, that oranger crab? He probably got it from one of his parents, who might’ve mutated that orangeness gene by accident.”
“Because kids look like their parents?”
“Exactly!” Test Tube removed the sample from the machine and re-submurged it in the ice bath, “Well, more like a combination of randomly assorted genes from all of their parents’ ancestors.”
Lightbulb frowned and pat Baxter’s head, “I hope the other crabs didn’t bully them for being orange.”
“If they did, their karma was probably death.”
“What?”
“Yeah!” Test Tube nodded, moving over to the whiteboard, “Because the third letter stands for selection. Or as I like to call it, survival of the fittest. What if this hypothetical college crab friend ends up being able to camouflage in red seaweed better? Its color fits the environment better, so it has a higher chance of surviving!”
Another timer went off, and Test Tube pulled the bottle from the ice bath. The lid came off with a pop, and she spread the liquid DNA on a plate. “Over time—the fourth letter—since this orange crab was so good at surviving, all his genes will be passed down to his kids, who will survive better and have more kids!”
“That’s a lot of kids.’ Lightbulb said, “If that’s what surviving is, Baxter is surviving—he’s thriving! So where are his kids? I could do with being an auntie.”
“Survival isn’t all there is to it. On top of natural selection, there’s also sexual selection.”
“Blegh.”
Test Tube inserted the plate into the frutiger aero machine, and turned it on, “You see this in animals like pewfowl and deer, and often leads to sexual dimorphism. I bet you didn’t know only the male peafowl have those pretty feathers to attract a mate, while the females are all brown.”
“The girlies have self-confidence and know their worth, and let the guys fight over them. Mad respect.”
“Depending on Baxter’s species, he could be outcompeted by a male with larger, more impressive claws.”
“I retract my respect! Why are they so vain?” Lightbulb lamented with perhaps a bit too much dramaticism.
“All is not lost for our involuntary celibate friend.”
“Don’t call him that.”
“This sounds horrible to say—uh,” She rubbed the back of her neck, “but if suddenly… I don’t know, a storm or earthquake kills a bunch of Baxter’s brethren, he’ll have less competition and the quote, unquote, ‘girlies,’ will lower their standards. That’s the beauty of the bottleneck effect, I guess.”
Lightbulb turned away, rubbing her hands together and thinking. Before any crazy conclusion sprung to mind, Test Tube commandeered a laptop on the counter, and clicked through results.
Baxter scuttled over, and Lightbulb craned her neck to see over Test Tube’s shoulder. “So what’s the prognosis, doc?”
The screen displayed four rows of letters that made no words, along with some gaps inserted between segments. Lightbulb squinted and read, “Atg? What the beans does that mean?”
“ATG.” Test Tube corrected, pointing to a different line that started with the same three letters, “It’s the start codon for the genes I amplified.”
“I have no idea what that means, just—tell me what species Baxter is.”
“I’m looking.” She replied through gritted teeth, scrolling through the lines of letters. Every so often, a trio of identical letters would be highlighted across different lines in bright purple. “I built this program myself, so it’s still a work in progress, and I haven’t finished the UI, buuut…”
Lightbulb huffed and leaned back. After a couple of minutes, Test Tube got a result.
“Okay—okay, as I expected, Baxter does not belong to the brachyura order.”
“English, Tubbette.”
“Baxter’s closest living relatives are lobsters and hermit crabs. He’s… not a true crab.”