For the plumage I wanted to add an element that hinted at the fact that this animal is, ultimately, an alien. For the most part I kept it feathered but, for the head, I added a crest that was comprised of a thin membrane of skin that was stretched between long, stiff quills with a feathered tuft on the end of each one. There are a few bird species that use stretched, colourful skin for display purposes such as the Frigate Bird. However, the skin stretched across quills to form a crest is a feature more strongly associated with the frilled lizard which, in turn, gives Quadornis a subtle alien feel.
A frilled lizard using its frill in a threat display
Frigate bird with an expanded "balloon" of skin which is uses to impress females.