Pygs

Pygs (Proboscissus pygmaeus) are a species of Mowboar. They are descended from Siberian subspecies. Pygs are found in the Siberian glowcaves. Pygs first entered the caves when started to become a sandy desert and the heat would kill them. 

Pygs are half the size of a normal mowboar. Their smaller size is a result of needing to fit in the caves. The only part of their body that wasn't shrunken over the generations was the trunk. The Pyg's trunk is highly sensitive to their surroundings in the caves, which makes up for their poor eyesight. Their ears are hypersensitive as well, being able to pick up vibrations. 

Pygs eat mostly fungus, insects, small rodents, and sometimes each other. As a result of the occasional cannibalism, prion diseases induce madness in Pygs. Their tusks shrunk significantly and turned back into normal canine teeth.

The social system for Pygs is the exact opposite of their ancestors, with Pygs being solitary. When mating season comes around Pygs follow pheromone trails through the caves until they eventually find their mates. The pyglets fight each other while nursing in order to get to the more nutritious milk, the weakest of the pyglets rarely survive to adulthood.

Territories are never shared between Pygs. Sows are free to pass through any territory they like, but whenever a boar goes through another boar's territory, a bloody brawl occurs. Pyglets aren't safe to traverse into other territories as well, as their fathers grant them protection and to leave that protection is to be eaten.