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ahamkara-apologist · 16 days

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Not to be insane in your inbox but I simply MUST hear more of your Uluran specbio headcanons. They keep me sane.

Okay yeah I'm just gonna post this now- been fiddling with it for several weeks and keep getting distracted by cool reproductive biology facts (like the complexities of rhino cervixes and why it makes conservation efforts via artificial insemimation so difficult) so here ya go. Most of this is reproductive biology bc I'm studying to be an evolutionary geneticist for conservation purposes, so be aware of that- all that good stuff is under a readmore

*Note: I started using the terms ‘bulls’ for male Uluru and ‘sows’ for female Uluru midway through this bc I got tired of writing ‘male/female’ over and over again, as this doc also contains Eliksni and Hive biology musings. It helps distinguish the Uluran section from the others a bit. I also use Uluru/Uluran interchangeably, with ‘Uluru’ being the notation for individuals and ‘Uluran’ being the notation for a group/the species as a whole.

General:

-The exposed upper gumline we see in almost all Uluru faces isn't how their lips normally rest; baring the teeth and upper gum is an expression of superiority/confidence in their strength. The reason we almost always see their faces in this position is because the Uluran almost universally view humans as weaker, and even those like Caiatl (who has seen otherwise) does it on instinct because they cannot fathom how much smaller we are

-Which, to be fair, doesn't say a lot; an Uluru with a relaxed mouth typically only occurs in private, when around their mate or equals. When an expression can mean both 'I am greater than you' as well as 'I am confident in myself and my abilities', and the whole society they live in is based around being the best of your class, then it's going to be a very common facial expression

-(On a side note: their growth hormones being triggered by a sense of pride isn't actually all that outlandish. House Sparrows exhibit a similar occurrance in real life, where winning dominance battles against other males increases the size of their bib, a black patch on their chest that indicates where they are placed in their social hierarchy. The more fights they win, the bigger their bib)

-Uluran fat distribution is mostly internal, and is focused around the organs to act as shock barriers when fighting; their muscles typically layer over the fat bands. The one exception to this is around the throat/jowl area, where fat layers over the thick muscle pads to help protect the vulnerable area from being gored by tusks during fighting

-Unlike in human society, hitting on a married individual is not socially unacceptable, especially if the individual doing the flirting believes that the pairing is an unfit match for one another and they can do better. It's considered romantic and marriage-affirming for the partner who's being shamed in this situation to chase the other suitor off. This weighed especially heavily on the sows bc of the vulnerable mate-guarding lactation period post-pregnancy

-(However it should be noted that Uluran gender roles are less restrictive in some ways than humans bc they’re based more on the strength of the individual than their ability to perform preset social rules, and that in modern times this is more for show)

-Historically, reverse-harem groups were a common sign of status, with one particularly fit sow mating with three or four bulls and/or having ‘lesser’ males that she did not mate with (or stole from other sows) nursing her calves. In some extremely traditionalist groups/among gladiators, this still occurs, but most mating groups max out at three individuals because the posturing required to keep people interested is just…a lot. Its a lot of mutual impressing to do

Reproductive biology:

-Much like hyenas, sows have a pseudopenis that is a result of increased androgens, and big pseudopenises on sows are seen as a mark of great status/strength. Tusk size/growth rates is also sometimes correlated with pseudopenis size, since the amount of androgens in the blood stream are correlated with both tusk growth rates and penis size

-Unlike hyena pseudopenises, however, the urinary tract does run through the shaft of the clitorus, while the birth canal essentially opens halfway down the shaft, creating a pouchlike vaginal opening. Arousal is required for this pouch to unfold; if not, penetration cannot occur, and in an unaroused state, it collapses in on itself into the base of the shaft, which then folds into the sheath for total protection. This evolved to keep the genital area clean, but has been co-opted to prevent mating until the female is ready, much like hyenas

-Yes, in less civilized times the pseudopenis was also used for dominance displays. During the breeding season, sows would evert their hemipenes in a half-erect state to essentially show off their fitness, which would greatly influence male mate choice. Tusk size = general status, penis size = reproductive status

-Bulls only receive a spike in androgens after the sows actively courting them go into an estrus cycle, which triggers increased sperm production and makes their testicles swell in size to what would be normal on a mammal (inspired by how bird testicles increase in size during mating season) and skyrockets their seminal viability 200% above average, specifically for the purpose of fertilizing a female in estrus. After fertilization occurs, they have to be around a pregnant sow for an extended period of time to a.) drop them back to a normal, non-breeding state and b.) induce lactation for the arriving calves, which is typically when mate guarding begins to occur in earnest. Both hormone cycle mechanisms are pheromonally regulated, but may have a 'ghost cycle' occurrence where the hormone fluxes occur on a very minor level

-As a consequence: very humanly 'masculine' bulls are typically less traditionally attractive compared to bulls with what we might consider more 'feminine' traits. Bulls with too much testosterone will have tusks on par with sows, larger penises, and testes that are noticeably descended from the abdominal cavity. While they are typically more capable of fertilizing sows, they are incapable of producing milk or are subpar at it, which means they cannot gestate the resulting calves effectively, so that increased fertility is essentially useless

-(However, it is important to note again that Uluran gender roles do not correlate to human ones, and high-testosterone bulls will still be considered very valuable fighters, warriors, and champions. They're just not considered suitable mate material, and are laughed or scoffed at if they ever want to have a family of their own. Ghaul was an example of a high-testosterone bull)

-[OOPS I ACCIDENTALLY WROTE THIS TWICE BUT DONT WANNA DELETE IT] Fertilization is internal and requires cooperation of both parties to occur. The female vaginal opening itself is composed of erectile tissue, and directly connected to the base of the pseudopenis; when aroused, it everts from the body cavity in an unfurling motion (as the outer labia are composed of thick skin that tuck inwards for protection) and sticks out a bit for ease of penetration.

-The male penis does much the same, but is long, thin, and semiprehensile, allowing it to easily curve under the curve of the abdomen and slip into the vagina via touch alone. The head flares after ejaculation to scrape out the sperm of opposing males, but isn’t terribly effective at it, as it is composed of soft, spongy tissue to be able to exit the tighter vaginal opening. Because bulls typically pick only one sow to mate with, the effect is not terribly drastic compared to, say, the Eliksni (who are much more promiscuous)

-Vanilla sex is typically done standing, with abdomens pressed together and reciprocal stimulation occurring in a slow rocking motion until orgasm is obtained. Casually reclining is another option, but the evolutionary default was to mate while standing bc it allowed for quicker reaction timing if a threat approached

-Uluran have 5 nipples, placed under the main abdominal fat pad and covered with their pouch, which is a flap of tough hide with very elastic skin around its edges that can be torn away if a certain pattern of muscle contractions occur (much like lizard caudal autonomy). Both bulls and sows have a pouch that can be opened, but it is vastly reduced to a mere fold of skin on sows. The pouch typically only opens when stimulated by the birth of calves (triggered by the scent of newborn calves), or when stimulated from within. The skin that seals it shut has no pain receptors, and calf ejection has to be voluntarily triggered in order to occur- the default pathway is 'closed'.

-Births are a private affair, limited only to one's mate; a midwife and their apprentice may come stay on the property, but typically only come in if something is wrong. Even though Uluran calves are born underdeveloped, much like marsupials, they also suffer from the same evolutionary blows dealt to humans in that an upright stance and larger brains made birth more difficult. Pair that with the fact that they're coming out of a narrow birth canal, and yeah, first-time births are often quite painful; Uluran culture typically see birth as a battle, and first births (where tearing of the vaginal canal almost always occurs in some capacity) as a blood rite.

-If possible, the calves are born onto the bulls's abdomen as he guards/monitors his mate, which is all the help that they are traditionally allowed to get as they crawl into his pouch and latch onto a tear to complete development. Any that fail to reach the pouch are left to die

-Up to five calves can be born at a time, but 2 is typically much more common. Of a five-calf litter, only four will ever be healthy; the fifth will always be a runt, and almost never survive. Six is practically unheard of, and always leads to the litter dying because all of the other calves are too underdeveloped to have been carried to term

-Calves are roughly palm-sized when born, and are a stoutly compact, rectangular pink blob of flesh. They're essentially fetus potatos, with the only developed part of them being their crawling limbs. Their skin is transparent, thin, and heavily vascularized, especially along their bellies, as the interior of a bull's pouch is also highly vascularized, and oxygen exchange occurs through cross-current exchange across the skin. Once they find and latch to a nipple, the babies will essentially fuse belly-first to their father's pouch + teat, and will stick there until they're developed enough to leave the pouch and start breathing on their own (the thick hide on their bellies is the last thing to develop before leaving the pouch). This also means that calf ejection is almost always fatal, as it involves the tearing of that oxygen-exchange patch

-Uluru milk consists almost entirely of protein, with the remaining content being mostly fats. There's very little sugar in it, and just enough water to give it the consistancy of something slightly thinner than heavy cream. It's basically an antibody-packed protein shake, and allows the calves to grow at tremendous speeds once born. They're capable of tripling their weight in the first week alone

-(Coincidentally, how fat a baby is when they leave the pouch is deemed a way to tell how fit the male is to be a father. The fatter the baby is, the sexier the male, as that means he's fit enough to be producing very high-quality milk at very little cost to himself)

-(Yes this means that Calus was peak dilf material in Uluran terms. Deal with it)

#destiny 2 #speculative biology #alien biology #uluran #uluru #cabal #anon #reply #destiny 2 headcanons #long post #ill draw pentis and vagoo diagram later. for now. potato babies and evolution hcs #(btw i had to stop myself before I made them triploblastic like i nearly did for eliksni dhfhdj)

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