“X bodily fluid is just filtered blood!” buddy I hate to break it to you but ALL of the fluids in your body are filtered blood. Your circulatory system is how water gets around your body. It all comes out of the blood (or lymph, which is just filtered blood).
“Okay but why is it always so chemically roundabout and unnecessarily complicated” well buddy, that’s because your blood is imitation seawater. See? It’s very simple.
Buddy if anything is living in your blood (except for more parts of you) in detectable amounts then you have a serious microbial infection and need to go to the hospital.
Humans are seawater wastelands kept sterile of all but human cells, with microbial mats coating their surfaces.
Thank you that’s…very disturbing
It’s not my fault you’re human.
Ok but “It’s not my fault you’re human.” Is the best comeback ever.
You can use it against anyone except children that you biologically helped to create.
Picture this: you are a Thing That Lives In The Ocean. Some kind of small multicellular animal a long time ago, before proper circulatory systems existed. “Wow,” you think, metaphorically, “it sure is difficult to diffuse chemicals across my whole body. Kinda puts a hard limit on the size and distance of what specialised organs I can have. Good thing I have all this water around me that’s the same salinity as my cells (they have to be that way so I don’t explode or shrivel up) so I can diffuse and filter chemicals with that.”
“Wait a minute,” you say a couple of generations later, because you’re not actually a small animal but an evolutionary process personified and simplified to the point of dangerous inaccuracy for the purposes of a Tumblr post, “instead of losing all these important chemicals to the water around me, how about I put it in tubes? I can keep MY water separate from the rest of the world’s water! Anything I want to keep goes in my water! Anything I don’t, I dump back into the outside water! I’m a genius! An unthinking natural trial-and-error process that’s a GENIUS!”
“Wow,” you think a great many generations later, “being able to have such control over such high concentrations of important chemicals is so great. Look how big I’m getting. I even have a special pump to move my seawater around, and these cool filter systems to keep the chemicals in it right, and that control and chemical concentration has let me grow so many energy-intensive, highly specialised organs! Being big is so hard. I need special cells just to carry my oxygen around now, to make sure my enormous, constantly-operating body has enough of it.”
At this point you are embodying a fish, and eventually, fish start straying into water with different pressures and salinity levels. (I mean, they do that since befor ehty’er fish, but… look, I’m trying to keep things simple here.) “What the FUCK,” you think. “My inside water is at a different salinity and pressure to the outside water?? How am I supposed to deal with that? I can’t have freshwater inside my seawater tubes! My cells have a set salinity and they would explode! I need to start beefing up my regulatory and filter systems so that my inside seawater STAYS SEAWATER OF THE CORRECT SALINITY even if the outside water is different! Fortunately, adding salt to my seawater is a lot easier than removing it, and I want to be saltier than this weird outside water.” At this point you beef up your liver and urinary systems to compensate for different salinities. (Note: the majority of fish, freshwater and saltwater, have a fairly narrow band of salinities they can live in. Every fish doesn’t get to deal with every level of salinity; they are evolved to regulate within specific bands.)
You also, at some point, go out on land. This is new and weird because you have to carry all of your water inside. “It’s a good thing I turned myself into a giant bag of seawater,” you think. “If I wasn’t carrying my seawater inside, how would I transport all these important chemicals between my organs and the environment?” As you specialise to live entirely outside of the water, you realise (once again) that it’s a lot easier to add salt to water than to remove it in great quantities. Drinking seawater in large amounts becomes toxic; your body isn’t specialised for removing that amount of salt. Instead, you drink freshwater, and add salts to that. The majority of your organs are, at this point, specialised for moving your seawater around, protecting it, adding stuff to it, or taking stuff out. You have turned yourself into an intelligent bag for carrying and regulating a small amount of imitation seawater, and its salinity (and your commitment to maintaining that salinity) is based entirely on the seawater that some early animals started to build tubes around a long time ago.
And that’s what a human is!
Well, there’s another few steps, of course.
Because at some point, operating along lines of logic that worked out perfectly so far, you did decide to be a mammal.
A mammal is a machine for adapting to Circumstances. A mammal is a tremendously resilient all-terrain life-support system, with built-in heating, cooling, respiration, and incubators for reproduction. Mammals internalise everything (grudges, eggs) and furthermore are excessively, flamboyantly wet internally. Sure, everyone’s a bag of chemicals; but mammals slosh. Mammals took the concept of an internal ocean and took it in an unnecessarily splashy direction, added aftermarket mods and a climate-control system,
and just to show off, you leaned across the metaphorical gambling table and said: “my internal ocean is so good-“
“Bullshit,” said the shark, keeping it salty (ha)
“My internal ocean is so brilliantly resilient, more so than any of YOURS,” you said, holding their attention with a digit held aloft, “that for my next trick, I shall artistically recreate the ballad of evolution as a performance. I shall craft a complex chemical ballet depicting the origin of multicellular life - using some of my own material, of course-”
“Oh, ANYONE can lay an egg,” yodel the fish, and the ray adds: “ontogeny does NOT recapitulate phylogeny!!”
And you’re like, “yeah no, it’s an artistic rendition, not a literal thing. Basically I’m going to take some cells and brew them up-“
“Like an egg.”
“Like an egg. An egg but internally.”
“Yeah,” said the viviparous reptile, “yeah, like, that can work really well. I’ve always said it’s the highest test of one’s chemical know-how. It’s a lot of work. And forget about support from your family - forget about support from your PHYLUM - all you get is criticism.”
“I’m gonna do it on purpose forever,” you said. “The highest chemical, thermoregulatory, immunological, everything-logical challenge. It’s gonna be my thing.”
“I’m with you,” said a viviparous fish, stoutly. “Representation.”
You kindly don’t point out, once again, that you’re planning to do this outside the ocean, in a range of temperatures; carrying the dividing cells in a perfect 37.5• solution of saline broth in all terrains, breathing oxygen in a complicated matter, you know, bit more difficult; but you need your allies.
“It’s solid,” says the coelacanth.
“But is it metal?” says the deep-vent organism.
“Oh, it’s metal. I will feed the young,” you say, magnificently, “on an echo of the mother ocean. The first rich feast of cellular matter, the first hunt for sustenance, the first bite they sip of our liquid planet-”
Everyone waits.
“Will be a blood byproduct. My own blood byproduct.”
Everyone looks uncomfortable.
“But,” a hagfish says carefully, “don’t you outdoorsy guys still need your blood?”
You cough and explain that if you stay wet enough internally and hydrate frequently, you should be able to produce enough blood byproduct to sustain your hellish new invention until they can eat your peers.
The outrage that follows includes questions like “is this some furry shit?” And: “milk has WATER in it?”
And you won the bet. “My inner ocean is such a perfect homage to the primordial soup that I can personally cook up an entire live hairy mammal in it. And then generate excess blood byproduct from my body and give it to the small mammal until it gets big.”
That is an absolutely bonkers pitch, by the way, and everyone thought you were a showoff, even before the opposable thumbs. When the winter came, and the winter of winters, and the rain was acid and the air was poison on the tender shells of their eggs and choked the children in the shells; when the plants turned to poison, and the ocean turned against you all; when the climate changed, and the world’s children fell to shadow; your internal ocean was it that held true. A bet laid against the changing fates, a bet laid by a small beast against climate and geography and the forces of outer space, that you won. The dinosaurs fell and the pterosaurs fell and the marine reptiles dwindled, and you, furthest-child, least-looked-for, long-range-spaceship, held hope internally at 37.5 degrees. Which is another thing that humans do, sometimes.
