(urth) Today, a Sea Slug. Tomorrow, ... ?
jerry_friedman at yahoo.com
Thu Jan 28 17:52:02 PST 2010
--- On Thu, 1/28/10, Jeff Wilson <jwilson at io.com> wrote:
> On 1/17/2010 10:14 PM, Jerry Friedman
> > --- On Sun, 1/17/10, Jeff Wilson<jwilson at io.com>
> >>> Severian's friend the Green Man
> >> always seemed quite plausible to me. I
> >>> hadn't realized just how plausible. Apparently
> a sea slug has
> >>> incorporate algae genes into its genome and
> produces and uses
> >>> chlorophyll inside its body:
> >>> http://www.sciencenews.org/view/generic/id/53496/title/Sea_slug_steals_genes_for_greens,_makes_chlorophyll_like_a_plan
> > That's pretty amazing, if it's confirmed.
> Did you see the thing last year? A predator microbe that
> photosynthetic if it eats this other microbe, then fissions
> into the original separate microbes again?
Missed that one.
> >> There's still a question of him being able to
> intercept enough sunlight to
> >> be more active than a slug. A man-sized silhouette
> in Earthly conditions
> >> intercepts less than 100 calories worth of
> sunlight a day.
> > Is that with perfect efficiency? Gosh, are you
> > telling me to do the calculation? Half a square
> meter in
> > sunbathing position, 1 kilowatt, 8 hours, that's
> > kJ or about 3400 big calories. You're assuming
> > like present photosynthetic efficiency.
> He said it was pond scum, so I presume it was something
> vaguely like pond scum.
Sure. I just wanted to know what you were presuming.
> >> From the Green
> >> Man's sunny smile, his people apparently still
> have humanlike teeth, so
> >> presumably they can eat a variety of food to make
> up the deficit, but I'm
> >> not sure if reducing your food needs by 1/30 is
> worth the hassle.
> > The sun could be brighter in his time than ours, and
> > engineering could have improved the efficiency of
> > photosynthesis and that of metabolism.
> maybe, but 30x as efficient?
As you said, he probably still needs to eat. If between
more sunlight and more efficient photosynthesis and
metabolism he gets ten times as much as we would, it
would reduce his need for food by about 1/3, which seems
worth some hassle.
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