On the Womb Nest and Kit Developmemnt
Oviposition in yinrih is a voluntary process. In tree dwellers and presapient yinrih it’s triggered by geophagy (eating soil) which sets of a cascade of metabolic processes that results in egg formation. In modern yinrih, eating dirt is replaced by clean sanitary over the counter pills.
Yinrih egg-laying is a much more arduous process compared to oviparous Earth animals. Both males and females lay very large eggs, since the yolk needs to help grow not only the kits, but also the womb nest that forms around them. The laying process looks much more like a human giving live birth. It’s painful and may last for hours. The ovary is destroyed in the process of oviposition and does not regrow. Yinrih musk (both ambient and ink) changes noticeably after the egg is laid, and different terms of address are used for pre- and post-egg males and females.
Modern yinrih place their eggs in an incubator. Incubators are famously sturdy. They’re connected to a uninterruptable power supply, provide clean and filtered air to the womb nest within, contain a suite of sensors and monitors, are fireproof and submersible in up to 12 tailslengths of water, and can even withstand small arms fire. Overkill? Almost certainly. But that’s what happens when you have two to six anxious fathers in charge of protecting the nest. Traditional yinrih gender roles put the sires on point for making sure the kits are yeaned healthy, and the modern incubator is the result of dozens of millennia of paternal instinct-driven technological advancement.
So-called “natural brooders” think incubation is excessive to the point of being harmful to the kits, and choose instead to keep the womb nest exposed to air in a cool dry place. Natural brooding is a very controversial movement akin to Terran antivaxxers. (The two ideas overlap significantly, as many cynoid vaccines are delivered in utero by the incubator automatically at specific points in the kits’ development.)
The womb nest itself contains a simple heart and circulatory system, with a heavily vascularized dermal layer for gas exchange. A fair bit of kits’ weight actually comes from absorbed gasses and not just the yolk.
The heart is located at the posterior end of the womb nest, and a large umbilical cord runs along the ventral interior carrying blood from the heart, with smaller cords branching off of it in a bus configuration to supply each kit individually. Each kit is incapsulated in an amniotic sac, with these sacs lining the walls on either side of the umbilical cord. This arrangement, with amnions along the walls and the “plumbing” running down the center, is what gives missionary womb ships their name.
In very large litters, the kit furthest from the heart receives fewer nutrients than closer kits, and becomes a runt. The kit closest to the heart gets well-fed, and grows very large. This is what happened to Iris and Lodestar. Iris was the furthest kit in the nest, while Lodestar was closest to the heart.
It takes about 144 Yih days for kits to fully develop. The process of emerging from the womb nest is called “yeaning” in English. The word is also used for missionaries (or gel-heads) coming out of metabolic suspension.
The kits come out of the womb nest blind and immobile. Their eyes open and they start moving on their own after a few weeks. The dams take over once the kits emerge. Each dam carries a kit or two on her back, and lets them lap milk from her paws when they get hungry. Kits start eating solid food after about two years, at which point they are called “pups”. Dams will continue carrying younger pups on their backs for a year or two longer.
Once the pups are weaned, parental responsibility becomes much more evenly divided between the two genders, with both sires and dams taking turns looking after pups. The exact form this takes can vary widely by culture and time period. Some communities have childermoot and litter living under one roof, while others have parents living singly, with pups rotating between households.
Both speaking and writing develop in tandem, with language progressing much like it does in humans. Kits start “scribbling” with their writing claw on any available surface, mimicking written marks made by their parents.