Mummy-nest Flyer

The Mummy-nest Flyer is a small flying creature native to planet Darwin IV's northern tundra. It has a pair of fast-moving wings, which allow it to hover like a hummingbird; and a long rigid tail which is bent downwards.

The Mummy-nest Flyer is so named because it makes its nest inside the mummified corpse of a much larger creature, dried out by the constant arctic wind. The nest's entrance is located where the corpse's head should be. Near it is a small bioluminescent appendage which likely helps the little flyer to find its way to the mummy-nest. It is later revealed that the nest animal is actually still alive and kept so by the flyer's nurture. Although their relationship is never explained in detail, it seems likely that the flyer brings food to its host, which in turn provides warmth and shelter.

While this could be explained as some strange form of symbiosis, Barlowe also proposes a theory in which the flyer and the mummy-nest were, at one point, part of the same organism. The portion corresponding to the creature's head develops wings and breaks free from the rest of its body, which is then mummified by the wind and becomes the nest.