Here are a few things I learned while sketching a flying fox. “Megachiroptera” means “Giant Hand-Wing.” With a four to five foot wingspan, it’s one of the biggest bats on the planet, and perhaps the best living inspiration for dragon wings.
The wing is supported with thin arm bones and finger bones that match up with our finger bones, including the knuckle joints. The clawed “thumb” sticks forward of the wing. For a vampire bat, it’s useful for holding onto the host animal when it is sucking blood. The other fingers spread out to support the membrane, with the fifth finger pointing back to support the trailing edge.
The bones in bats’ fingers have less calcium than our bones, and they’re flattened a bit, so they can bend without breaking. The skin is stretchy, thin, and delicate. But if it rips, it can regrow.
As with birds and pterosaurs, there is a bit of membrane forward of the elbow. The membranes have muscles and blood vessels in them, and they’re covered with some fine hairs. They also have receptor cells that can feel how much the skin is stretched.
When I drew this specimen, which hangs in Harvard’s Museum of Comparative Zoology, I wasn’t sure what causes those yellow-brown bands in the wing. Maybe one of you is a bat expert and can explain.
More on bat wings at Animal Diversity
