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Invisible wrote:
> The question is... why are leaves green in the first place? Wouldn't
> they work so much better if they were black??
Leaves are green because water passes green light (to a first approximation).
First plants evolved just below the surface of the water, with purple (red
and blue) color. I.e., the first plants absorbed the abundant green color
while reflecting both the infrared and ultraviolet that was dangerous. You
still see some plants and most photosynthetic anaerobic single-cell
organisms with this coloring. It's also the stuff in your eyes that lets you
see better after 10 minutes in the dark.
Then oxygen-creating photosynthesis evolved in bacteria that lived *under*
the layer of purple algae, which absorbed the purple reflected from that
algae, and hence looks green.
--
Darren New, San Diego CA, USA (PST)
There's no CD like OCD, there's no CD I knoooow!
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Warp wrote:
> No, it's because of the surface temperature of the Sun. Both leaves and
> best vision is at the green amplitude for a common reason.
If green was the best color for light absorbtion, the leaves wouldn't be
*reflecting* green. :-)
--
Darren New, San Diego CA, USA (PST)
There's no CD like OCD, there's no CD I knoooow!
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"scott" <sco### [at] scott com> wrote:
> > Just pondering that evolutionary adaptation is fascinating.
>
> http://www.sciam.com/article.cfm?id=evolution-of-primate-color-vision
>
> Might be of interest...
Cool! Thanks for that. I need to get that issue of SCIENTIFIC AMERICAN; not
only does it discuss this very topic, but also 'dark energy.' Being a closet
cosmologist at heart, the issue should keep me fascinated for weeks!
KW
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I wonder why WE can't see into the ultraviolet (and the infrared?) That
SCIENTIFIC AMERICAN article points out that some existing creatures can see at
least somewhat into the UV spectrum. So their retinas(?) must have developed
some kind of protection that we don't (currently!) have. "Man is the superior
being.": Bah, humbug.
And if we could see into the infrared, then Traci would be looking *oh* so much
nicer. ;-P
KW
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"Kenneth" <kdw### [at] earthlinknet> wrote:
> And if we could see into the infrared, then Traci would be looking *oh* so much
> nicer. ;-P
You might say she'd be looking even hotter.
;-)
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From: Le Forgeron
Subject: Re: Very interesting color resolution examples
Date: 28 Apr 2009 16:29:18
Message: <49f7671e@news.povray.org>
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Le 28/04/2009 18:14, Darren New nous fit lire :
> Warp wrote:
>> No, it's because of the surface temperature of the Sun. Both leaves and
>> best vision is at the green amplitude for a common reason.
>
> If green was the best color for light absorbtion, the leaves wouldn't be
> *reflecting* green. :-)
>
In fact... leaves are not reflecting green... they are reflecting light which YOU
perceive
as green.
Not the same thing.
Take any satellite view in IR or UV, and you will see (in false colors) that all
plants
are not the same "green" (as well as providing information about water-need, it's also
changing from species to species: some smart agency detects drugs-fields that way).
As leaves in autumns show, they have various pigments to react with the light.
Chlorophyll (the whole family) works less with green. Hence the green of leaves.
But in the family, some are more efficient on different red/IR/blue/UV.
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Le_Forgeron wrote:
> In fact... leaves are not reflecting green... they are reflecting light
> which YOU perceive as green.
Well, true. Green, amongst others. :-)
> As leaves in autumns show, they have various pigments to react with the
> light.
Is that really where the colors come from? Other cholorphyll-related chemicals?
--
Darren New, San Diego CA, USA (PST)
There's no CD like OCD, there's no CD I knoooow!
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On 4/28/2009 10:02 AM, Kenneth wrote:
> Being a closet cosmologist at heart, the issue should keep me fascinated for weeks!
Dude, did you just come out of the closet on the POV-Ray newsgroups? :o
:)
--
...Chambers
www.pacificwebguy.com
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Chambers <ben### [at] pacificwebguycom> wrote:
> On 4/28/2009 10:02 AM, Kenneth wrote:
> > Being a closet cosmologist at heart, the issue should keep me fascinated for
weeks!
>
> Dude, did you just come out of the closet on the POV-Ray newsgroups? :o
>
> :)
Yes, it's true, I can finally admit it: I AM a wanna-be cosmologist!!
Ah, that felt good. Now I don't have to hide my true feelings from my friends
any longer.
KW
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From: Mike Raiford
Subject: Re: Very interesting color resolution examples
Date: 30 Apr 2009 13:07:32
Message: <49f9dad4@news.povray.org>
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Kenneth wrote:
> I wonder why WE can't see into the ultraviolet (and the infrared?) That
> SCIENTIFIC AMERICAN article points out that some existing creatures can see at
> least somewhat into the UV spectrum. So their retinas(?) must have developed
> some kind of protection that we don't (currently!) have. "Man is the superior
> being.": Bah, humbug.
Well, they can detect UVA, yes, which is mostly harmless. It's UVB that
causes burns and cancer.
And some people can see just barely into the IR band. I'm one that on
certain IR remotes, I can just barely see the die light up. It's
probably very long wave red that I'm actually seeing, though.
--
~Mike
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