Yes, I do sometimes still draw. This is a bit of speculative biology I took up back in August at the behest of Dan Koboldt, who wanted a picture of a dragon. This…isn’t that.
Instead what I did was think about the dragons of Naomi Novic‘s Temeraire series. This…isn’t that either. Clearly, I was wrong, but when I was reading the first book, I had the impression that the dragons’ wings were elongated ribs, like those of living Draco lizards and the diverse (and unrelated) “rib-gliding” reptiles of the Triassic.
I started by illustrating an Icarosaurus, but actually picked a better candidate for dragon-hood: Celurosauravus, whose “wings” were supported not by ribs, but by boney structures growing out of the skin.
How could these structures evolve into a real wing capable of powered flight? Perhaps like a botfly, whose flight biomechanics was so beautifully diagrammed by Walker et al.’s time-resolved microtomography studies. Walker et al. found that the whole thorax of the botfly works like an engine, with three parts pumping against each other as the wings flap. If we imagine something like that evolving from Celurosauravus, we get this.
The flapping wings provide power, but control (and at larger sizes, lift) is provided by the membranes stretched across the hind legs. The clawed forelegs support the animal on the ground.
Dragons (more properly dragonettes) diversified through the Mesozoic and Cenozoic, and today occupy niches from tiny, hovering nectarivores to soaring predators and even large, heavy flightless forms. Although some extinct species achieved leg-spans of four meters, stories of dragonettes large enough for humans to ride can be safely dismissed as myth and wishful thinking.