[TML] Alien ecologies

[Knapp]

On Fri, Aug 29, 2008 at 2:36 PM, Jerry W Barrington
<jerry.barrington at gmail.com> wrote:
> On 8/29/08 3:37 AM, "Knapp" <magick.crow at gmail.com> wrote:
>
>> Also, leaves are not thin for that reason. For example Cactus,
>> Lithops, Jade plants, (ya, all high light level plants BUT orchids,
>> Epiphylllim Both have thick leaves and live in low light. I think
>> leaves being thin is more related to structural needs concerning
>> support. On the other side the chlorophyll is often near the surface
>> but the flesh could still be blocking some wavelengths. Is there some
>> data out there about that? It is not my field.
>
> Well, all those plants are using special water conservation systems, which
> is what overrides the normal tendency to thin leaves.  And in at least a
> couple of cases, it may technically be a leaf, but realistically it *is* the
> structure of the plant.  And as you mention, the chlorophyll (and thus the
> photosynthesizing) is in the skin layer.

I still don't think the thinness comes from the needs of the
chlorophyll to get light down to it. Perhaps from a flat area being
the cheapest structure to get exposure for the chlorophyll when other
things don't override that need. You could study leave structures your
whole life and not know or understand it all. It is a REALLY
interesting subject about evolution, utility and structure. I would
bet changing the sun would change it and or the wind or the weather
(rain) or the gravity or the dirt.

Ah, How about those really thick seaweeds? Sorry, I don't know their
names. They are not after water.



-- 
Douglas E Knapp

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