From: Eugene Leitl (eugene.leitl@lrz.uni-muenchen.de)
Date: Wed Aug 04 1999 - 16:56:29 MDT
Jeff Fabijanic writes:
> I consider that 'frozen',
> whether or not all the liquid in their bodies was crystalized or simply in
> a colloid 'slush'. I have had people question whether Lucky-fish too, was
Sorry, commonly the word frozen is used to denote a liquid system
totally undergone phase transition. I may partly freeze an alcohol or
salt solution into a sludge (=water ice crystals in unfrozen
solution), but this is not homogenous ice. (The process of
supercooling a liquid until it turns into a (meta)stable glass is
called vitrification, btw).
Neither occurs with freeze-hardy higher animals. They all die if
cooled deep enough for the residual liquid to freeze. Suda's
experiment won't work if you try it with liquid nitrogen.
> simply quiescent in the unfrozen muddy silt at the bottom of my pond. Let
> me assure you, on my very exposed deck, up here in New England, the fish
> pond (which is a 40gal tub supported on blocks with no insulating material
> under it), with only several gallons of water in it (ie <2 inch layer),
> freezes completely after a few days of <10°F weather. After 60 days of
> continuous frost, it is *rock* solid frozen. And that little fish, maybe
^^^^^^^^^^^^^^^^^^^
That's how it appears superficially. ~260 K is not cold enough by far
for that. Try dry ice or nitrogen, and then rewarm the fish. Surprise!
> 2-3 oz at the time (much larger now), was assuredly frozen solid as well.
> There was even a fishy-shaped cavity on a couple pieces of the ice slab
> that I removed.
All this has very little to do with the internal state of the
organism. I may freeze an animal heart "rock solid" by briefly
submerging it into liquid nitrogen. It will even resume beating if
rewarmed. Unfortunately, "rock solid" only refers to the outer shell.
> It may say in cryo textbooks that higher animals don't freeze, but having a
> brother who personally discovered several new species of insect in NJ in
> the 1980s, I have a good appreciation for the incompleteness of our
> official understanding of the natural world.
Cryobiology might be incomplete, but it is not *that* incomplete.
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