Repetitions

"What do you think life beyond our Earth would look like?" "Considering there are zillions of planets out there, I think there exist mathematical probabilities that there could be repetitions of shapes that occur on our Earth." "I see what you mean: bird-like things, fish-like things, and so on..." "Yeah, they could evolve in parallel, or they could be offshoots of panspermia, but that's another class for you!"