Re: Lichens implausible.
Note I said IF there are microbes on Mars then lichens could plausibly also exist.
The question of organics on the surface of Mars is still not definitively settled:
Vikings would have missed life on Mars
Early Mars lander missions lacked the acuity to sniff out life.
13 February 2001
PHILIP BALL
http://www.nature.com/nsu/010215/010215-11.html
Bob C.
