Jim Cooper (jkcoope at students.uiuc.edu) wrote:
: In article <4ch239$n04 at net.bio.net>, Hani Jabr <hani at tartarus.uwa.edu.au> wrote:
: ]) Hello. I've got a question:
: ]) I've heard from a friend that non-carbon based life has been discovered
: ]) near undersea volcanoes. I was wondering if anyone could supply me with
: ]) more information, or an idea of where to look for more information.
: On numerous occasions I've heard of the possibility that conditions near
: undersea vents might be similar on Europa. I'm curious whether anyone
: could offer me information, or a place to look, to help me clarify the
: Jim Cooper
: Dept. of Philosophy - Univeristy of Illinois
I think there is a little confusion here. I am currently reveiwing a book
"The microbiology of hydrothermal vents" edited by David Karl, published
in 1995. It is a collection of some of the foremost workers in this area.
I think the original quetioner meant not "non-carbon based life" but
habits that obtained their primary energy from a source other than
photosyntheticly fixed inorganic carbon. When hydrothermal vents were
first discovered, some 21 years ago the great excitement was that this was
possibly the case - entire communities of bacteria and animals completely
dependant on geothermal energy. This remains a possibility but it also
remains an untested hypothesis - the mechanics and costs of producing
unequivocal data from reseach in this environment make progress slow.
David Karl also outlines three alternative hypotheses, two of which seem
perfectly possible (ultimately using dissolved organic matter or
sedimentary organic matter as a primary energy source - both of which are
photosynthetic in origin), and one which seems less likely
("photosynthetic" bacteria able to use the comparatively very low
wavelengths of heat radiation as an energy source). Of course it may be a
combination of any or all of these.
Basically, it is possible that hydrothermal vent communities may not be as
isolated from the surface biosphere as was once thought to be the case.