You are applying the numbers Gary used for starting a colony inappropriately to his and mine long term view of a Martian colony. A Mars Colony will not be self sufficient initially, it will just be far more self sufficient than possible anywhere else in the solar system off of Earth and therefore far less expensive.
With careful genetic testing/planning and artificial insemination or changes in social practicies I think a colony could be founded with far less than the traditional limiting population that Gary gave. A 10,000 number is what I've heard is required for a full fledged society. On the other hand a population shortage is sure to spur advances in automation which is intellectual property that could be exported back to Earth (with 0 launch cost) in trade for supplies.
Regards,
Mark
Space/Science » in reply to re: Ditto that
A Slight Misunderstanding