The Evolution of the Monotreme

Zoe has a question about monotremes, the only mammals that lay eggs. Is there any evolutionary advantage to that? We've got Jack from JBRA here with his questions on platypus and a kibna. Dr Carl will be sitting across you for 16 hours during our Q&A session. Does it hurt? Is it painful? Well, I'm tossing up whether or not to get it at this stage. Have you got some little tattoos? I have a couple of little ones, yes.