You mean you don't flip every crab over and check for eggs before releasing them into the aquarium??? Did you point out that the crab "sex" occurred before you put it in his aquarium? How many times have you put a Molly into an aquarium and they have babies (currently on cycle 2 of new molly - 18 babies, ugh!)? It just happens! It means the aquarium is healthy. How many microscopic things are breeding in his aquarium? Or for that matter, how many bacteria are breeding in his office? Let it go, he is being ridiculous.