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NewsHour
Backgrounders
June 10, 1997:
A Gergen dialogue
with William Broad about his book "The Universe Below."
April 10, 1997:
NASA scientists explain the
findings from Europa.
Browse the NewsHour's science
coverage.
Outside
Links
Browse stories from the New York Times by William J. Broad and others on Europa. (note:
free, but registration is required.)
Browse Simon & Schusters' page on "The Universe Below: Discovering the Secrets of the Deep Sea."
|
 And,
finally, The Online NewsHour asks:
In your book you write about fantastic creatures
living on the ocean's floor. Did those creatures evolve from animals
that once survived in a solar, or "sun-based," eco-system or did they come
first and solar-based life evolve from them?
William Broad responds:
Many scientists now believe that the Garden of Eden, so to speak, was
dark as night and that the light eaters came much later. By this view,
many creatures of the ocean's dark ecosystems are descendants of the planet's
first life. Photosynthesis is a very tricky process to perfect, and is
now thought to have arisen fairly late in evolutionary history. Carl R.
Woese of the University of Illinois has compared the genetic makeup of
many plants and animals and found that heat-loving organisms in the hot
vents of the deep sea are members of a class that appear to have undergone
less evolutionary change than any other living species on the planet, implying
that their ancestors were perhaps the original forms of life. He has dubbed
these old microbes Archaea, or ancient ones. The Archaea are seen as a
third major branch of life, alongside bacteria and all higher organisms.
Archaea love hot environments heavy with sulfur, apparently having lived
unchanged in the hot vents of the deep sea for ages. They are the founding
link of the lush ecosystems of the undersea darkness, where tube worms
can grow up to lengths of 14 feet and number in the thousands.
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