[TML] Alien ecologies

[shadow at shadowgard.com]

On 20 Aug 2008 at 22:46, Jerry W Barrington wrote:

> Purple thing are reflecting both blue and red and absorbing the colors
> between.  This is exactly opposite of chlorophyll.  (They may also absorb or
> reflect IR or UV, but our eyes don't see that.)  Also, note that human
> vision is most sensitive in the green, and that is also where the Sun's peak
> emission is.  Actually makes it kind of odd that plants *aren't* purple, as
> green is where the most energy is.  Although, they tend to be a *dark*
> green, so apparently they still absorb a lot of the green.

The oddity is yet another proof that evolution tends to find *local* 
maxima in efficiency.

Cholorophyll evolved early and is "better" than the other such 
chemicals that had evolved. There may be better possibilities, but 
you can't get there from any of the alreadsy evolved pigments without 
going thru intermediates that don't work worth a damn.
 

--
Leonard Erickson (aka shadow)
shadow at shadowgard dot com