Don’t wait for clanking robots on Mars to do what flesh-and-blood humans do better. The opportunity is now for a new branch of civilization to claim the fourth planet from the sun. That’s the opening call from a “Red Planet platoon” from more than 700 people gathered here for the Third International Mars Society Convention, running through Sunday at Ryerson Polytechnic University. “From a technological point of view,” said Mars Society President Robert Zubrin, “we are much better prepared today to send humans to Mars than we were to send people to the moon in 1961 when John F. Kennedy started the program.”