QUESTION: 
Was there ever life on Venus? If so, how did it die out.

ANSWER from Jack Farmer on November 20, 1996:
There is no evidence of an ancient rock record on Venus today. In fact,
the surface is quite young and has been completely resurfaced by volcanic
eruptions. But the atmosphere of Venus bears clues of an earlier
water-rich environment which may have made life possible. The evidence is
in the ratios of hydrogen isotopes (isotopes are different species of the
same element that differ only in the number of neutrons in the nucleus).
This affects the atomic mass. The hydrogen in Venus' atmosphere is
enriched in the heavy isotope of hydrogen. This suggests that a whole lot
of hydrogen and water were lost to space, and further implies there was
once water there!  Since liquid water is the key to life, it is possible
that there was once life on Venus.

If life did develop on Venus it probably died out because of the
increasing temperatures that happened because of the Greenhouse effect on
Venus. The sun was less luminous early in the history of the solar system
and has gradually warmed up. As that happened, Venus became a hot-house
and lost its water and life, if it was ever there.