Spectember 2024 #04: Forest Gelada

Someone who identified themself only as Pendrew asked for a “ruminant-like Old World Monkey”:

A shaded sketch of a speculative descendant of geladas. It's a baboon-like quadrupedal monkey with front limbs longer that the hind limbs giving it a sloping back. It has a long almost horse-like snout, small high-set eyes, small ears, a rather long neck for a primate, and a short tufted tail. Its front limbs are digitigrade and have large curved claws, while its back limbs are plantigrade with smaller nail-like claws.

After much of East Africa rifted off into a separate continent, shifting climate turned the alpine grasslands of what was once the Ethiopian Highlands into into warmer subtropical forests – and the highly terrestrial grass-eating geladas that inhabited the region adapted to new sources of food.

Yedenigelada pendrewsii is a large quadrupedal herbivorous monkey, about 1.5m tall at the shoulder (~5′). It has a specialized pseudoruminant digestive system with a three-chambered stomach, similar to that of camelids, and it occupies an ecological niche convergent with the ancient chalicotheres, selectively browsing on trees and shrubs while sitting upright and using its long clawed forelimbs to pull branches within reach. 

Unlike its highly social ancestors this species is mostly solitary, although during the breeding season groups of males come together in leks to compete for female attention. Displays consist of inflating large colorful throat pouches to make loud resonating calls, and flipping upper lips to bare teeth and gums.

A shaded sketch of the head of a speculative descendant of geladas, showing its upper lip flipped up to display its teeth and gums, and an inflated red throat pouch.