re: I don't know who .......
Gee you seem really paranoid over this guy. He's just a college professor not the head of MIB. What could he do to stop you, or are your arguments for Mars so weak they will topple if even one person questions them?
BTW I have read Zubrin's book as well as The Hunt for Life on Mars by Donald Goldsmith which I recommend you read.
Yes it may eventually take humans on Mars to rule life out, however there are a number of experiments robotic landers may do to narrow the field down before hand.
