Now you are just being silly. > > What about Mr and Mrs Slug? Aren't they hermaphrodites?-I know they are h's. I said there were stages of sex development. And I was being a little cute. But I have a real point: how do two lines of organisms accommodate when they must? I've discussed mother and child with enlarging head (different DNA). What of some of the cooperative actions I presented in Nature's IQ? With chance mutation and natural selection,I seriously wonder how it works.