Re: "The Scarcity of Life Bearing Planets"

On Jan 2, 10:41 am, Chalky <chalkys...@xxxxxxxxxxxxxxxx> wrote:
On Jan 2, 4:15 pm, Chalky <chalkys...@xxxxxxxxxxxxxxxx> wrote:

On Dec 22 2009, 8:23 pm, "Revres" <rev...@xxxxxxxxxxx> wrote:
On the Earth,
life does not seem to prosper above an altitude where the density is half an
atmosphere. At the other end of the scale, the atmosphere must not be too
thick or the wavelengths of radiation needed for photosynthesis not only
will not reach the atmosphere-water interface where life begins,

Not true. There is ample evidence of life supported only via the
emissions of " thermal vents ", and located  more than a mile below
the oceanic surface, hence not subject to photosynthetic
considerations.

However, of maximum importance here is the following fact:
For the earliest anaerobic lifeforms, oxygen was a poison, and so it
was only via the evolution of lifeforms which excreted oxygen (ie
photosynthetic plants), which both benefited their own well being, and
assisted in killing off their competitors, thus giving rise to an
atmospheric situation which encouraged the evolution of animal life.

I dunno why you are even bothering to reply. The author posts the
same junk day in and day out, changing call-signs when he/she/it is
kill-filed by enough users. It, for lack of gender, never bothers to
reply, or acknowledge that there are challenges to its nonsense by us
learned users.

Kill-file it, and move on.
.

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