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Howto - Flying Snakes
Ant writes "Wired News' Furthermore mentions a University of Chicago researcher finally figured out exactly how the limbless reptiles pull off their amazingly effective bird imitations. 'Despite their lack of winglike appendages, flying snakes are skilled aerial locomotors,' said biologist Jake Socha. Here's how: First, they flatten their bodies from head to tail, making themselves 'Frisbee-like in form,' Socha said. Then, as the snake drops (or leaps!) from a tree branch, it sends S-shaped waves through its body, steadying itself as it glides through the air. One species can even turn mid-flight. There is more information, photographs, and even short QuickTime video clips on Jake's Flying Snakes Home Page."
Mirror of the flying snake "takeoff" and "gliding" videos.
(The author has also stated "You may use this video footage for non-publishing purposes without permission" on his web page. Not sure how much load it can handle, so I figured I'd mirror it. The author's page has more information and commentary; these are just the raw videos. They're very small, so there's a good chance his server could have handled it just fine.)
Cool... Google is your friend:
g dom/wildkingdom.htm
http://www.museum.tv/archives/etv/W/htmlW/wildkin
From the link:
Unlike Zoo Parade, Wild Kingdom was shot on film almost entirely in the field, and featured encounters with wildlife in their natural habitat. Indeed, one of the program's signature features was the footage of Marlin Perkins, or his assistants Jim Fowler and later Stan Brock, pursuing and at times physically engaging with the wildlife-of-the-week, whether that meant mud-wrestling with alligators, struggling to get free from the vice-like grip of a massive water snake, running from unexpectedly awakened elephants or seemingly angered sea lions, or jumping from a helicopter onto the back of an elk in the snows of Montana.
$0.02 (CDN)
Flying snakes, however, differ from all of these in one rather interesting way: they will actually move the airfoil while airborne, and appear to be swimming through the air. What's interesting is that the glide angle gets shallower when they do this. This suggests three possibilities: (1) this behavior reduces drag, (2) this behavior increases lift, or (3) this behavior produces thrust.
The last would be really interesting: if flying snakes can actually produce thrust while airborne (even if they can't develop enough thrust for horizontal flight), then they would be only the fifth animal group (alongside insects, pterosaurs, bats, and birds) to evolve true powered flight.
but in a more reserved, 70's, quiet manner.
You must have been born after the 70's if you apply terms such as "reserved" and "quiet" to its manner.
"You will know when it's time to turn the page when you hear the calliopie (sp) play like this. Let's begin now."
It certainly was from Dumbo (I had the book & record version). The three crows that feature throughout the story sang that song.
Of course, Shrek was NOT done by Disney - in fact, it was full of thinly veiled barbs AT Disney...
A critical part that your explanation is missing is that the difference between a potential flying snake and its children would be very, very small. Some snakes would have bodies in a slightly different shape than others, so they would be slightly more successful at making jumps to capture tree lizards and therefore would be on average slightly more well-fed and slightly less likely to die before reproducing. Over thousands of years, this disparity creates a trend that results in more and more of the snake population being better and better at gliding. Dawkins explains it much better than I can.
Also, in response to the other subthread here, small animals can survive falls from far greater heights than humans can. If they're robust enough to survive impact at their own terminal velocity, then they *can't* die from falls (unless they land at a funny angle or on something very bad). Cats can survive falling off a 10-story building because they reflexively spread out, increase drag, and hit the ground at a lower velocity. A snake that's good at jumping and gliding would have no problem falling out of a tree.
A few random comments about these postings:
o ns.html -- there are many more details about the snakes' trajectories, particularly in the latest papers (2005).
Regarding the mirror of my site--thanks. The was so much traffic this weekend that the server was brought down. When I called the company, they said, "So YOU'RE the problem here..."
Gliding is a form of flight in which the flier can only move downward. Thrust is required to move upward. As was suggested, it would be very interesting to learn if a flying snake generates thrust (though not enough to overcome its weight).
I actually tried to use a contrasting sheet on the ground to improve the visuals, but the snakes would have none of it--they would glide anywhere but there. They have good vision, and seemed to prefer natural settings. I spent countless hours squinting while analyzing video, trying to make out white spots on a green and black snake against the green grass.
"Ultra light bones" The paradise tree snake is better gliders than its cousin the golden tree snake, and the paradise tree snake on the whole is less robust. I would like to test the idea that its bone structure is different (particularly, thinner-walled), but I haven't gotten to that yet. Similarly to many scientists, I have a long list of things I'd like to work on...
Regarding the "does it really" line of questioning: all gliders take a curved trajectory. At the end of the trajectory, the glider is moving at a shallower angle than at the beginning. For some of my snakes, they reached a glide angle of 13 degrees from the horizon. Not anywhere as good as a bird (2-4 degrees) or a man-made glider (even better), but impressive for an animal that in reality is a cylinder. I also suggest you look at some of the publications at http://www.flyingsnake.org/publications/publicati
-Jake Socha