On Mon, May 12, 2014 at 04:49:27PM -0400, Richard Aiken wrote:
> The supposed advantage is that (at least in the introduction's
> author's view) the silicon-based lifeforms don't need to use water
> nearly so much as carbon lifeform. I'm not sure what is being used
> in *place* of water, but the lack of internal water apparently
> contributes o the increased tolerance.

The proposal was that they use short-chain liquid silicone compounds.

> NOTE: Sounds like Ullerans would make for great spaceship crew
> (particularly at H. Beam Pipers tech level); don't need water and
> can tolerate extreme temp ranges, plus armored skin that would
> likely be proof against brief exposure to vacuum.

Human skin isn't bad at surviving low pressures.  Our most rapidly
fatal problem (and likely also a problem for Ullerans) is that there
is no oxygen, and that has nothing to do with skin.  It's a function
of our respiration and circulatory system, and especially the oxygen
requirements of our brains.

There are plenty of possible adaptations to vacuum conditions, but
there is no reason to expect that Ullerans would fare any better than
ourselves in such conditions.  It's quite as likely that they would
handle it even less well than humans.

- Tim