While yinrih are arboreal, the proportions of their digits and palms are closer to those of humans rather than arboreal apes like orangutans and gibbons. Those animals have long fingers and toes to wrap around large branches. While they do have thumbs, orangutans can't oppose the thumb to the other fingers because the thumb is much shorter than the fingers.

Because of Yih's lower gravity (about 0.88g), the branches of the trees that yinrih dwelt in are proportionally slimmer, meaning yinrih digits need not be so long. Further, when yinrih did encounter larger bows, their claws could dig into the wood to help stabilize them.

Yinrih can also wrap their rear thumbs behind them when squatting on a branch, like the zygodactyl feet of a bird.

The pads of yinrih paws may be covered in tiny keratinized bosses or even barbs like the tongue of a cat. These would be for grip when climbing.