#evolutionarily

[runawaymarbles]

actually i think being fascinated by the process of lighting things on fire is what makes us human

[planariaareneat]

How The Nocturnal Bottleneck and Nipples Make Us Human

Almost every post here considers what humans do have, really. It’s a little tiring; realistically every world has its harsh environments and vicious species and a sophont to match. We probably wouldn’t be unique for our adaptability or our persistence or even adrenaline

But our evolution is fucked up as hell, to put it lightly.

Mammals went through what’s been dubbed the nocturnal bottleneck essentially since the start of the mesozoic right up until the Cretaceous ended the archosaur’s exclusive hold over the daylight. We lost a lot of things from every mammal spending most of its time in either a cramped, suffocating burrow or scrounging around in the faint hours of nighttime. Our blood cells lost their nuclei to hold more oxygen while we spent time deep underground, we lost protections against ultraviolet rays in our skin and eyes, we can’t even repair our own DNA using the light of the sun. Most aliens probably wouldn’t have such traits unless their evolution followed a very similar path to ours. They’d be able to see ultraviolet and wouldn’t have to worry about sunburn and all the wonderful privileges essentially all fish, birds, amphibians, and reptiles enjoy as we speak. 

There’s also what we gained from spending so much time in the dark.

Brown fat is only found in mammals, it’s a special type of fat which bear cells with several oil droplets and are utterly jammed with mitochondria. This lets it make heat, a lot of it, fast. We don’t even need to shiver to induce this heat generation from brown adipose tissue - factor in our downright hyperactive mitochondria, and we can warm up quickly. Sure, it doesn’t have too much use in adult humans, but it keeps our infants warm and still provides a little boost the whole run we have in this universe.

Unless aliens also went through a time where their small ancestors had to face cold nights, they’d have to produce heat the old fashioned way when chilled. Aliens might have to shiver the whole time they’re in a cold room while the human watches in confusion, quite literally unshaken, and wonders if the room is a lot colder than the thermostat set to 60 says. The aliens stare at their companion in confusion, it’s just a normal temperature to shiver at after all, how is the human sitting so still?

Our small ancestors spending all their time out foraging at night is also why we have such a good sense of touch, smell, and hearing. They were more important senses than vision (we’re lucky to have even redeveloped basic color vision, frankly) at the time and place and simply ended up continuing to serve us well. Birds and reptiles rarely have acute senses of smell and the latter especially are lucky to have acute hearing, and birds rarely have impeccable hearing themselves either. Our skin is free of scales and honed to sensitivity, and our external ears and complicated ear bones provide an immense range of hearing (from 20 all the way to 17,000 hertz!).

Aliens might not be able to pin down the chirp of a cricket or the light click of a lock being picked. The human might be the only one on board a ship that can pick out the finer sounds of the engine’s constant thrum and know the critical difference between when everything is fine and when something is wrong. The human could probably pick out the sounds of an approaching enemy’s careless footsteps - they’re only as light enough for *them* to stop hearing them, after all - and be the one to see the horrified expression (well, more on that later) on their face when we get the drop on them in spite of their perceived stealth. 

But perhaps the most versatile, convoluted, amazing, and utterly unique trait we have is right on your face this instant. Lips.

Lips in most animals are a simple seal to hold in the mouth’s moisture and protect the teeth, even if they’re supple they’re NEVER muscular except in mammals, and we have only one thing to thank for it; milk and nipples. Lips evolved exclusively to allow babies to suckle, it required a vacuum to be created in the mouth, and with no other animal having anything like a nipple it never happened in other animals. Many animals make milk, to be frank, but no other animal has nipples.

Your cheeks and lips are a marvel among tetrapods, no other animal can suck like mammals can. Aliens wouldn’t have straws or even be able to sip from the edge of a glass, they’d have to have a proboscis or simply tilt the whole thing back. Aliens likely won’t have woodwind instruments or balloons you can blow into. We take so much about our lips for granted. Hell, our muscular faces are vital for expressions, we’re probably absolute facial contortionists among a cast of creatures with mandibles and beaks and expressionless scaly maws. Aliens might find us ridiculously easy to read, if anything, compared to their own kind (all the better to deceive them) - or perhaps they’d find us hard to decipher anyways, with our lack of color-changing skin or erectable crests of bright feathers. Baring teeth might not be seen as a sign of aggression in most of the universe, smiling would be all too distinctly human. 

Perhaps with how infectious we are sometimes, that’s what we’d contribute to the universe; others might have to make do with opening their mouths just enough to show their teeth or splaying their innumerable mouthparts with just the right curve, but perhaps we’d teach the galaxy to smile, one ally at a time. 

Wouldn’t that be amazing?

[enigmaticpink]

On the topic of not assigning human morals to animals, I think we need to talk about how people talk about cuckoo birds is really anthropomorphizing

That's not an evil soulless creatin, that's a baby bird surviving the way it has evolved to. It's not up to you to decide that actually this baby bird deserves to survive and this one doesn't. This is simply how nature is and we should not be assigning our own morality to it.

[uter-us]

radfem question!!

i'm having a conversation with someone about female only spaces (this specifically pertains to bathrooms) and they said that the rule of having female-only bathrooms would "act more like an enforcement of femininity more than anything else."

I think their point is about butch lesbians and/or women who present "masculinely," and so because there is ofc no female identification at the door, and policy would likely just make it more acceptable for women and girls to report if there was a male in the bathroom (without having to determine if the male identifies as a woman), this could end up hurting "masculine"-presenting women (implying that they could be mistaken as male), and in turn just reinforce femininity. Thoughts? (mine are in tags)

[clodiuspulcher]

today im thinking about malaria in ancient rome.

about the fact that P. falciparum (the most dangerous kind of malaria) was likely endemic at least from the 2nd century BC onward that Galen said semitertian fevers (P. falciparum infections) were more common in Rome than anywhere else in the Roman Empire that the most severe manifestations of P. falciparum (quotidian fevers + cerebral malaria) were most common in babies and young children, an epidemiological observation that indicates the transmission rate of P. falciparum was extremely high in Rome that Quintus Serenus said there was no Latin word for semitertian fevers (they used a transliteration of the Greek, 'hemitritaeos') because "no one, i think, could have named it in our language and mothers would not have wanted to"

[specialagentartemis]

Wait if the human body needs fats for protein absorption, do you have any idea what someone who can't process fat at all is supposed to do? I'm currently being evaluated for all kinds of possible diagnoses but so far my physician isn't sure what's wrong with me and if it's curable, but the gist is that I literally can't eat anything even slightly fatty without becoming severely sick and immediately having to run to the bathroom. So I can't eat any meat that isn't lean, I can't eat cheese, can't drink milk, I can't eat yoghurt that isn't advertised as 0 fat, and I can't use oils at all either.

From what you're saying about fats, that sounds...less than ideal. Considering I don't know for how long I'll be forced to live this way or if there's anything that can fix it at all, do you know if there's anything I can do to prevent the rabbit starvation you speak of?

(referring to this post) Oh, wow! I’m sorry, that sounds frustrating and stressful.

I want to be clear: I’m an archaeologist, and my primary understanding of this comes from an archaeological and evolutionarily perspective, not a modern nutritional one. Your doctor and your nutritionist will know a lot more about your case than I do.

That said, rabbit starvation/protein poisoning is only really a concern when lean meat makes up the majority of your diet. Not the majority of the meat in your diet, the majority of your diet, period. It’s a topic of interest among archaeologists in particular because it would have been a perennial concern in the winters during the Ice Age: when hunting animals with lean meats would have made up a large portion of early humans’ and Neanderthals’ diets during a Paleolithic winter. Historically, this tends to happen only in the winter in tundra and subarctic regions when grains, fruits, vegetables, nuts, and fish aren’t available. There’s a reason it’s also called mal de caribou.

Carbohydrates, sugars, fruit, and vegetables give you a much more balanced diet and help make up for deficiencies in other areas. And modern nutritional supplements, fortified foods, and multivitamins also help stave off many historical areas of malnutrition. If you are eating a modern spread of foods, even without fat, you are very unlikely to get protein poisoning. You might get constipated when you eat the meat, though.

My understanding is: proteins get digested faster than fats. So if you eat high-protein lean meats, they can move through your system quickly, without your body having time to extract all the amino acids and all the nutrients from them. And then the undigested bits can build up in your colon and make you feel constipated. Fat is digested more slowly, and when eaten with protein, allows your body more time to extract more and fuller suite of nutrients from the protein. Possibly there is also an emulsification aspect going on as well, I’m not positive and it’s hard to find good explanations that aren’t diet-culture-focused. (Fat also does other important things in your body with providing long-term slow-burning energy, padding your organs so they don’t impact against other parts of your body, and absorbing fat-soluble vitamins and such; again, I’m not a nutritionist, and I don’t super understand the details.)

But dietary fiber can also slow down digestion, and can help give some of those same digestive effects. (Nixtamalized) corn+beans+squash is a very traditional diet of the Americas because it gives the whole suite of necessary amino acids without requiring a whole lot of external additions. Also, I get the sense that fish like salmon work differently because of omega-3 fatty acids? So there are for sure things you can supplement with.

My post wasn’t intended to make people worry; modern nutrition and food availability means that there is a lot of flexibility you can have in your diet if you’re allergic to one aspect of it. It was meant to say, even “unhealthy” fats have an important place in a balanced diet, and can do good things for you besides just tasting good, and that craving it may well mean there’s something in there that your body wants. But if fat genuinely isn’t good for you for medical reasons, there are absolutely ways of dealing with that. Ultimately, variety is the most important part.

[fisheito]

Lol angst ? about nukani , my super unserious gayporngacha game? Can't be that bad

(10k words later into a fic) Ooohh.ohhh it was a mistake. I should not have read this hahahahahahahgyrk *choking sounds*

[defectivegembrain]

I am putting "aspie supremacy" on the high shelf that term is very specific and does not describe every single instance of an autistic person thinking they're better than others for experiencing something more mildly. For example, the concept of "Asperger's" never ever indicated that a person had less intense special interests. The people who called themselves aspies were, in my experience without exception, very proudly obsessive. The people saying you should just be able to stop having a certain special interest are not aspie supremacists, they are wrong and ableist for different reasons.

[unprotectedmechs]

how about traumatic insemination. how do we feel about traumatic insemination

[coinfl1p]

this is why i should just kill myself i say some stupid shit and then she probably wants to leave me which is the correct and good option for this scenario but i shouldnt say stuff bad enough to make someone wanna leave in the first place

[quantumshade]

job interviews are so fucking evil i'm so stressed for literally no reason

[clockworkflicker]

okay so sirens, mermaids, etc, right? imagine a variety of aquatic humanoid that bioluminesces when sick. their speckled cheeks literally glow with fever, and their irritated nose and gills can be spotted at a distance even in the murky depths.

bonus points for messfuckers if their mucus also luminesces

[dibatag]

Kinda hard to read, but basically ceratis are more closely related to wet nosed primates such as lemurs, than they are to us, despite the similar looking faces

[oceancoresunset]

Unfortunately for some reason crabs trigger my arachnophobia (I think it’s the legs) but I am forcing myself not to be scared of them because they are just little guys

[royalreef]

POINT AND LAUGH AT THE LANDFOLK GETTING STUNG BY JELLYFISH. SUCKS TO BE YOU.

[monstermoviedean]

i mean just think about talking to an ancestor who lived a thousand years ago and saying i have a magic tool that lets me talk to people halfway around the world even if we don't speak the same language. and i use this incredible tool to be rude to strangers.