Re: Colors of alien plants -- Scientific American

Eivind Kjorstad wrote:
> Typical vegetation convert at best 1% of the incoming photons to usable 
> energy. This compares pretty poorly with even todays crude solar-cells 
> which can easily do 10% and we've got designs that in principle should 
> be able to go to 30-50% (depending on your level of optimism)

On the other hand, how easy is it for those solar cells to be 
synthesized by protein-based cellular mechanisms from raw materials that 
are readily present in an aqueous solution? Does the increased energy 
efficiency of the new photosystem make up for the increased energy cost 
of making the new photosystem in the first place? There are always 
additional factors involved in these sorts of evolutionary issues.

For something that evolution's been noodling over for so long and that 
has such a major impact on organism fitness I think it's a good default 
assumption that the current design balances the tradeoffs in a 
near-optimum manner given the environment the organisms are dealing 
with. Green-harvesting pigments exist and plants have been known to swap 
genes around with wild abandon so there's probably a better reason for 
why they're not widespread than "nobody's tried it in the past half 
billion years".