Chapter Text
Dr. Ryland Grace settled down at his Eridian organ, cracking his knuckles like a pianist about to begin a symphony. As he sat, he heard his students quiet down to hushed murmurs.
♫Good morning, class. Did everyone do their homework?♫ He keyed out. Their homework had been to write a very basic report on any Eridian microorganism. He would collect their writing tablets after class was dismissed.
♪Yeah, it was gross. Do we have to learn about germs, question?♪
Grace sighed. This was almost as bad as when he covered human culinary culture. How could he expect the unit on pathogens to be any different? ♫Yes, Malachite. I will not belabor the point, but it is important to study bacteria and other microorganisms. Though maybe I am biased.♫
He got a chuckle from the class for that one.
♫Okay, okay. I think you guys will like this one, though. Today, we are covering♫ “viruses” ♫which is probably best translated as…♫ His fingers hovered over the keys, eyebrows knitting together with concentration. Translated as… little pathogens? Cell-invaders? Yeah, okay, I like that.
♫We can call them cell-invaders, because that’s exactly what they do. They breed by invading— Hold on, I need my board for this.♫
He stood and began drawing on his whiteboard. It had a magnetic backing that allowed the ferrofluid-based ink of his marker to cling to the board at enough of a thickness for his students to detect it. He drew a very basic diagram of an animal cell and a bacteriophage-like virus.
“This—“ He pointed to the cell, “is our animal cell. Or body cell. Or bacterium or whatever. It’s just minding its own business when a virus comes along. Viruses are bundles of proteins that contain RNA and… that’s about it. Back when I was on Earth, we still weren’t sure if they counted as alive or not. They don’t really... think. They just float around in a medium until they touch a target cell.”
He took a breath.
“Sorry, I’m getting ahead of myself. Let’s start from the very beginning. Regular cells have to take in food to survive. Think… taumoeba eating astrophage. Viruses don’t eat. The whole purpose of a virus is to multiply. They do this by making contact with a target cell and either fusing with it or otherwise injecting it with its own genetic material. The internal ‘machinery’ of the cell then reads the RNA of the hijacking virus and produces the proteins instructed by the RNA. This is pretty much always more viruses. Eventually, there are physically too many viruses inside the cell and it bursts, spreading the new viruses out to infect more cells.”
There was a cacophony of shudders and frightened thrills echoing across the room. Many students even hunkered down in their spots.
Grace sighed. “Don’t worry. It is very, very rare for an Eridian to get a virus. I didn’t even know you guys had viruses on this planet until, like, last week. I can count the number of confirmed infections in your entire history on one hand.” He held up his hand for emphasis.
Pyrite raised a claw.
Grace wasn’t the most creative namer, this was well-known, so his students had been happy for him to give them English names based on the minerals they most resembled. Except for one kid who had become absolutely obsessed with Elvis and demanded Grace call him that. Kids, man.
“Yes, Pyrite?” He tried to offer her an encouraging smile.
Each new class roster chose a name and pronoun during orientation. They mostly picked their pronouns based on vibes, or asked Grace to pick if they couldn’t decide. He usually had an even spread of hes and shes, with a few theys and maybe one or two its per class. The Eridian language had no gendered pronuns, of course. “Pronouns” were actually a very shorthand version of someone’s name with tonal flourishes denoting relationship to the speaker. There was also a pronoun for those whose name you didn’t know yet. Grace’s public pronoun was something akin to “GraceHuman-Teacher-Savior”.
♪Do humans get viruses, question?♪
“Oh, all the time. There’s one we call ‘rhinovirus’, basically nose-virus, that we get so often we call it the common cold. Cold being the name for the syndrome, not having any reference to temperature. It’s so minor for most people we haven’t bothered to try and cure it. Well, I guess we’ve tried but not with much gusto. We’re very used to getting random viruses at least a few times over the course of our life.”
♪So humans do not need to care about viruses, question?♪
“Well… we do need to care a little. Some viruses cause more severe infections than others. Influenza, for example, is pretty inconvenient for most people. It can cause nausea, fever, nose leaking, aches, coughing, and more. It can even be deadly for people with weak immune systems, like children or the very old. We definitely take it seriously when someone vulnerable gets infected. Influenza is one of the diseases we vaccinate for. Who remembers what vaccination is?”
The entire class raised their claws. Grace facepalmed.
“Right, duh. Forget I asked.”
♪Cannot forget.♪ Someone chimed, eliciting several giggling thrills.
“Haha… You guys are just trying to distract me.”
♪Teacher Grace?♪
“Yes, Ametrine?”
♪How come Eridians do not get viruses? We get bacterial infections. What makes viruses different, question?♪
“That is a great question!” He shook his hands at her. “Bacteria attack other cells or produce toxins indiscriminately. Viruses are very selective. Every virus evolves to target one specific type of cell and nothing else. Because Eridians are full of worker cells that are very different from each other genetically, any virus that manages to get inside an Eridian will have a hard time finding a cell it can use to reproduce. The virus is more likely to die before it can reproduce. In humans, we are chock-full of nearly identical cells. Each of our.. muscle cells, for example, are pretty much indistinguishable from any other muscle cell. I could take a muscle cell from my arm and put it in my leg muscle with no problem. My body doesn’t know the difference. If a virus evolves to target my muscle cells, I’m in big trouble.”
He paused to take a sip of coffee from his desk, ignoring the chorus of jokingly disgusted whistles from his students.
♪Teacher Grace is a very bad Eridian! Very rude! Eating in public, grrroooossss!♪ Someone heckled.
“You can’t yell at me *every time* I take a drink.”
♪Yes we can.♪
“Ughh… That’s it! I’m going back! See you at the space elevator, I’m going back to Earth!” He dramatically stomped towards the door leading to the rest of his biodome.
♪Noooo!♪
♪Stay!!♪
♪No! Stay here! Earth is stinky*!♪
*More accurately translated as “bad-sounding”.
Grace chuckled, ignoring the tickle in his nose as his body considered crying. He was so loved. “Alright, I’ll stay!” He conceded, walking back over to the board. “Back to viruses!” He spread his arms emphatically.
The students cheered and trilled.
“Okay, okay. Anyway.” He raised a flattened hand, signaling for them to settle down. He resumed once they were at an acceptable level of quietness. An Eridian classroom was never silent. There would always be some random clicks of echolocation at the very least.
“Most viruses just kinda have their RNA free-floating for the target cell to read, but a few will permanently integrate their genes into the genetic material of the target. These cells are called retroviruses, because their effects can be seen generations after the initial infection. I think. Actually probably not… I’ll get back to you on that. Anyway! Very early on in human evolution, a retrovirus infected the gametes of some of our ancestors and harmlessly altered their DNA. These changes were passed on all the way down to modern humans. It’s estimated that about 8% of the human genome is derived from these ancient viruses. Usually, this doesn’t really affect anything, but occasionally these sections of DNA can be ‘activated’ by other viral infections. With most of those infections, you have much bigger problems to worry about than ancient viral DNA.”
He took another sip of coffee, just daring them to heckle him again. They didn’t, too enraptured by the lecture. Enraptured and slightly horrified.
“Viruses can be pretty cool, though. With the right engineering, you can change their RNA. Instead of telling target cells to make more viruses, you can alter them to instruct cells to make almost any protein you want. For example, there have been cases of people engineering viruses to cure them of their lactose intolerance. Isn’t that neat??”
♪…♪
He blinked, met with confused silence. Pyrite gave him some polite, encouraging jazz hands.
“Right.. I didn’t… Lactose is a type of sugar found in milk. Milk is a special food produced by mammals,” he gestured towards himself, “for our babies. It’s meant to be nutritious and calorie-dense so they can grow well. Baby mammals digest lactose with an enzyme called lactase. The vast majority of mammals stop producing lactase after they wean and start eating regular food. Many human cultures have the practice of drinking the milk of some farmed herbivorous mammals, even as adults. Some humans mutated to produce lactase into adulthood because of this, but some don’t. Those who don’t produce lactase get indigestion when they drink milk, a condition we call lactose intolerance.”
The students responded with subdued, polite notes of understanding. They didn’t want to interrupt him.
“The scientists bio-engineered a special virus that would target specific cells in the digestive tract and instruct them to produce lactase instead of more virus copies. It cured lactose intolerance, but temporarily. They would need to re-administer the virus after a few weeks, since the infected cells had been replaced. They also had to make sure that the virus was designed to not attract attention from the immune system. It was a really cool experiment, but not ready for the public or anything. I wonder if that’s mainstream by now. Maybe. I think I’m gonna end class here today. No homework tonight. Remember to put your tablets in the airlock before you leave so I can grade them.” He reminded them out of habit, though he knew he didn’t need to. “Tomorrow, we’re going into more detail on influenza. I promise, it’ll be worth it.”
He bid them goodbye using special musical jewelry Adrian had made for him. A cuff on his wrist featured ridges akin to those found on Rocky’s arm. He used an accompanying ring on his other hand to run his finger along the ridges and make the typical “see you later” notes.
As the students filed out, chittering amongst themselves, he cycled the airlock. He opened it and brought the pile of writing tablets to his desk. He opened the door to the rest of his beach biodome, then settled at his desk for a nice, relaxing grading session to the sound of the waves.