Description

The Yuo Yowa are remarkably similar to humans from the waist up. They have a large, muscular tail that they use for gripping and grabbing, as well as for balance and swimming. Due to the tail's weight, they don't walk as upright as humans but can rear up to an almost erect position, which can cause back pain if they do it for too long. They run with their bodies and tail in an almost horizontal position. The position of their body and tail is also important in non-verbal communication. The Yuo Yowa are digitigrade, with both their feet and their hands retaining retractable claws from their ancestors. The first digit on their feet is opposable and used for grabbing branches or gripping larger prey.
Due to pheomelanin being able to manifest in their skin cells just like eumelanin, they can have reddish and yellowish skin tones. When their hair grows, it starts out dark until the production of eumelanin halts, and the hair continues growing lighter or with only pheomelanin present, similar to agouti fur in cats and dogs.

Women in these charts have their hair cut short. Men have them in their natural length and structure.

Phenotype gallery

Biomechanics

Imagine designing a while world with solid mechanics, letting your creative juices flow, and then getting stuck because of a finger pic.twitter.com/71VZM22ooh

— Lizard🪲 (@lizardsaurus) September 23, 2023

↑ A video showing grasping capabilities of Yuo Yowa hands. Note that the pointer finger has no retractable claw. That is not accurate, I merely included it in the animation to directly see the difference from the behavior of other fingers.

Evolution

When their ancestors, the house cats, started exploiting a niche as a small, arboreal predator, one of them had a nanite mutate its forelimb claws in such a way that they were slightly more opposable. This individual passed it down to their offspring, because it happened to be an advantage for climbing and prey capture. As time passed and the ecosystem stabilised more, they began to grow larger as larger prey established their own populations in the rainforests. At this point, their ancestors weighed circa 60 kilograms. Due to their diet shifting to larger-sized prey, they slowly abandoned the tree canopy but still climbed on a daily basis. One branch of these moderately-sized felines slowly became more and more social, using their opposable thumbs for grabbing rather than restraining. They specialised in hunting larger prey in small groups, ambushing it from the treetops, gripping tightly onto it with their claws and beating it with rocks and sticks, which would often be thrown as well. This behaviour later developed into tool-making and more complicated hunting strategies. This lineage then resulted in the Yuo Yowa. What's also interesting is that they are the only sophont in Total Convergence..? that developed menstruation convergently with humans and a few other mammals.

Ontogeny and lifespan

Pregnancy lasts for five months and the babies are born blind, with curled-up ears and dark hair. They begin to open their eyes after a few weeks. The babies also have very short tails that begin to grow when they're around ten months old, and when the tail is proportionally longer than the child's body, it is considered a sign that the child is ready to start learning how to walk.

Diet

The Yuo Yowa are carnivorous, but they like to supplement their meals with spices and especially mushrooms. Their diet has to consist of at least 75% meat. Due to this, they never invented farming and thus never experienced a population explosion as drastic as ours, although some population explosions have occurred, they were never as large in scale as they were in human history. Those minor explosions were mostly caused by the invention of complex fishing, and fish and mussel farming. This also made them very vulnerable in wars and other political conflicts, because it is simply much harder to obtain meat than to obtain a potato when your country's economy is collapsing.

Genetics