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A Unified Theory of Animal Locomotion
Roland Piquepaille writes "You probably already know that there is a master equation for all life processes based on metabolism. Now, physicists from Duke University have applied the so-called 'constructal theory' to explain how running, flying and swimming modes of locomotion are similar even if they're apparently unrelated. This single unifying physics theory explains how fast animals get from one place to another and how rapidly and forcefully they step, flap or paddle in relation to their mass. In other words, these scientists argue that the characteristics of animal shape and locomotion are predictable from physics."
As far as I'm aware, fish have gills and lay squishy (scientific term) eggs, while birds lay solid eggs and have lungs. Birds also have feathers, and I'm not aware of any feathered fish.
And heck, if you're going to define our atmosphere and our ocean as a fluid medium, then you're saying that ALL animals are the same - name a single animal that travels through a completely SOLID medium.
http://www.TheGamerNation.com/Forums
Apprently you didn't look very well. Two links go straight to his blog.
"Or maybe a fish shaped like a donut?"
I hate to break this to you but most animals (including fish and humans) are shaped like donuts (tube surrounded by the organisim). This is not the only "body plan", there are ~30 others still around today, (eg: Jellyfish have only one orifice). All body plans that have ever existed hail back to (or before) the Cambrian explosion
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
As another poster pointed out, fish are boyant in water. They take advantage of this through an organ designed to control positive and negative boyancy (gas bladder). They use it to ascend and descend in depth without swiming. That's quite a major part of how fish move in water that's vastly different from how birds fly.
That's not to say that fish and birds aren't similar in how they move through fluids, but to say they're the same is a vast misunderstanding of fish and birds.
AccountKiller
Penguin FAQ
"Penguin feathers are short, overlapping and densely packed. The outer part of the feather is waterproof while the inner down section traps an insulating layer of air, keeping the penguin warm in the sometimes freezing water."
"the laws of physics dictate that a Bumble-Bee can't possibly fly,"
really should have been explained with the qualifier that (at the time) scientists' understanding of the Bumble-Bee's flight mechanics were not complete.
Time passed and someone sat down with a highspeed camera + some smoke and figured things out. I can't find a link to the explanation, but it has to do with vortices.
[Fuck Beta]
o0t!
[Ahem]
I have to type in some non cap letters here, otherwise the server won't let my quote pass. It is not my fault it's all in caps. That's the way it was written the first time!
So, without further ado, the quote, courtesy of that haven of IRC gems, bash.org:
YES IS NOT AN ANSWER TO "A OR B?"
Have you seen images of submarines where they still cause a bit of a bow wave when slightly submerged? Pushing against the water in front creates a bit of a ripple, and even though the total volume of the water is the same, part of it is at a raised height. Due to gravity, this ripple requires some energy that has to be exerted - just like the bounce in running.
But that's not the definition of buoyant, so quit being "clever":Birds are not buoyant in air. Not even one little bit. It's an absolute definition: "remain afloat", "upward force