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Author Topic: How do fish defy the laws of physics?  (Read 4008 times)

Offline thedoc

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How do fish defy the laws of physics?
« on: 21/10/2012 20:20:31 »
A group of researchers from Bristol University have discovered that the optical properties of a fish’s skin seem be more reflective than was previously thought possible for a non- metallic object...

Read the whole story on our website by clicking here

  
« Last Edit: 21/10/2012 20:20:31 by _system »


 

Offline Phractality

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Re: How do fish defy the laws of physics?
« Reply #1 on: 21/10/2012 21:49:02 »
Bumble bees fly without defying the laws of physics. We just didn't understand the laws of physics.

Apparently, there's still a lot we don't understand about optics. Perhaps the scales use total internal reflection to turn the light around. We should study the internal structure of individual scales.

Fish scales hold dazzling secret

« Last Edit: 21/10/2012 21:53:04 by Phractality »
 

Offline CliffordK

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Re: How do fish defy the laws of physics?
« Reply #2 on: 22/10/2012 01:04:46 »
Is a reflective fish skin actually a good source of camouflage?  That seems somewhat counter-intuitive, especially when I've seen videos of schools of brightly colored fish.  Perhaps it all depends on the amount of light, depth of water, background, and etc. 

Could nature have evolved highly reflective scales as a form of population control?



 

Offline Phractality

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Re: How do fish defy the laws of physics?
« Reply #3 on: 22/10/2012 02:40:50 »
Is a reflective fish skin actually a good source of camouflage?  That seems somewhat counter-intuitive, especially when I've seen videos of schools of brightly colored fish.  Perhaps it all depends on the amount of light, depth of water, background, and etc. 

Could nature have evolved highly reflective scales as a form of population control?
Most fish are dark on top, so they look like the deep water below, and bright on the bottom, so they look like the sky above. It's difficult to look as bright as the sky when you are illuminate by the dark water below. You have to rely on light from the side and reflect it downward.
 

Offline krool1969

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Re: How do fish defy the laws of physics?
« Reply #4 on: 23/10/2012 02:26:47 »
"Bumble bees fly without defying the laws of physics. We just didn't understand the laws of physics."

There is a myth that states scientists show that bumble bees can't fly. This isn't quite true. If you read the original paper it states bumble bees can't GLIDE. Not quite the same thing. The smaller an animal is, the harder it is for that animal to glide, that is, hold it's wings out and fly without adding thrust.

You can see this with birds. Large birds like eagles and buzzards usually glide. They user thermals as much as possible and flap their wings only when they have too. Small birds link finches never, if ever glide. There is a bird here in the PNW that never glides. He'll flap his wings a few times then fold them and coast a few seconds then flap again before he gets too low.

Bumble bees, being much smaller than even the smallest birds can't glide at all. But they have no trouble at all flying.
 

Offline Phractality

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Re: How do fish defy the laws of physics?
« Reply #5 on: 23/10/2012 17:59:21 »
"Bumble bees fly without defying the laws of physics. We just didn't understand the laws of physics."

There is a myth that states scientists show that bumble bees can't fly. This isn't quite true. If you read the original paper it states bumble bees can't GLIDE. Not quite the same thing. The smaller an animal is, the harder it is for that animal to glide, that is, hold it's wings out and fly without adding thrust.

You can see this with birds. Large birds like eagles and buzzards usually glide. They user thermals as much as possible and flap their wings only when they have too. Small birds link finches never, if ever glide. There is a bird here in the PNW that never glides. He'll flap his wings a few times then fold them and coast a few seconds then flap again before he gets too low.

Bumble bees, being much smaller than even the smallest birds can't glide at all. But they have no trouble at all flying.
StraightDope.com gives a better explanation. Actually, we didn't understand the aerodynamics of bumblebee flight until our computers were able to simulate it. The key is the formation of vortices above the trailing edge of the wing as it swings forward and back. If not for the extra lift generated by the vortices, the bumble would not be able to fly.
 

Offline JP

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Re: How do fish defy the laws of physics?
« Reply #6 on: 23/10/2012 18:05:01 »
"How do fish defy the laws of physics?"

They don't.  :)
 

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Re: How do fish defy the laws of physics?
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