Wednesday, May 4, 2011

Bat Wings

I have a feeling that one of you out there right now is designing the wings of a dragon, so this post is for you.


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

14 comments:

Michael Oxley said...

I just about fell out of my chair when I read this post! My sincerest thanks for the information, it will be a tremendous help!

Johnnyburn said...

Although I have no actual idea what the bands in the wing are, I think it would be interesting if they functioned like "battens" in sails -- keeping the curved surface wrinkle-free in the non-stretched direction.

P.T. Waugh said...

I would venture that the bands are thickened areas of skin used to support the shape of the wing (a bit like the wood strips on the Wright or Da Vinci fliers). That or stretch marks.

JonInFrance said...

I did a dragon drawing last week - too late, Jim, drat!

Christian said...

Haha! I'm bound to paint a dragon! ;-) Thank you so much, James!

Jobot said...

Elastin fibers, maybe?
http://www.brown.edu/Departments/EEB/EML/background/wing_anatomy.htm

I'm no bat expert but I do have enough extra time on my hands to search the Interwebs.

Munchanka said...

I think that's my favorite opening to a blog post. I'll be in a dragon gallery later this year, so this is definitely going in my bookmarks.

PAF said...

I think perhaps pterosaurs would be a better model than a modern flying mammal. The pterosaurs had a single elongated finger to support the membranous wing instead of using all the finger bones.

Unless you're working on little tiny bat-sized dragons...

Natalia M. said...

If you go to the zoo on a hot day, they'll hang open in an effort to cool off. I got a lot of great drawings at the Columbus Zoo that help a lot with some dragon reference. (i.e. http://img.photobucket.com/albums/v125/VulpesDragon/jhjkhgkjg.jpg) They might be trying to relax, but it looks like some pretty dramatic poses!

A Ro said...

Guess what, I'm designing a dragon RIGHT NOW and the wings are what I'm struggling with! Thank you for the pointers! :D

Peggy Stermer-Cox said...

Hi, I've been a silent follower for awhile. I'm thinking the bands in the wing could be blood vessels. They do have blood vessels, nerves and elastin in the wing. I studied bats a little bit many years ago in college. The wing is beautiful, soft, pliable. Fun post!

David Glenn said...

I have done some drawings of dragons, but unfortunately I can't get them onto the computer.

dragonladych said...

Having drawn dragons for the past 25 years and working in a bat research center I've spent hours observing bat wings. I always meant to build a wing model to get more convincing positions. But never made one.

It's really hard to properly understand how these wings are used even when you know the anatomy.

Not sure what the brown bands are, might just be wrinkles. I've never seen these big bats alive, but maybe it's also an artefact from the taxidermy.

steve molyneaux said...

hey james. Heres a interesting image showing the network in the wings.

http://3.bp.blogspot.com/_pao3QYgoqp8/TM2BCs8VOsI/AAAAAAAAASI/008bYaK8H5I/s1600/geometric+blog+bat+wings.jpg