Didontornis

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In the horsetail meadows of Ryl Madol, a strange fellow can be encountered, A biped, both feather- and furless. But, contra Plato, it is not man, nor even really mammal. Although now heavily altered and resembling more a naked, flightless bird than anything else, the two small tusks growing behind the beak still give away the true ancestry of this Paleozoic survivor. It is a dicynodont therapsid which has learned to walk on two almost humanoid legs. With these, as well as its horizontal pupils, it is well-equipped to evade the predators which may lurk among the tall seed-fern-flora. Yet, these little herbivores still tend to fall prey to the likes of lycaenoraptors and aistoboids.

Didontornis is a small browser that feeds on horsetails and other shrubby plants. These are cut off with the sharp beak and grinded up in the stomach using gastroliths. Only males have the distinctive tusks, which made classification of this species initially difficult when the first encountered specimens were females. The tusks probably serve as either a weapon or display feature during fights for mating-rights. The arms and legs are short and small and rarely used during foraging. When two didontornes get into a scuffle, they sometimes try to slap each other, which can look adorable.

Didontornis is just one member of a wider group of bipedal dicynodonts, the Diornithodonta, which on Ryl Madol have taken over a similar ecological role as ground birds and fowl would do elsewhere in the world. Their common name is “lystrodos”, a portmanteau of Lystrosaurus and dodo.