No planet is more earth-like than Earth itself, so if life really does pop up readily in earth-like conditions, then surely it should have arisen many times right here on our home planet? And how do we know it didn't? The truth is, nobody has looked.
“You take your life in your own hands, and what happens? A terrible thing: no one to blame.”
“True friends: only a few have 'em, but only a few will admit that they don't.”