the last set of ideas which i want to discuss, which is not  which are only partly related as a matter of fact to the erm ideas of the punctuationists, are the ideas, which, as a matter of fact my colleagues here brian goodwin and gerry webster have been particularly clear and eloquent advocates, which say in effect that if you really want to understand evolution, merely thinking about the adaptation of organisms to some kind of environment is not really an adequate way of thinking about it, because when you look at organisms, look at vertebrates for example, you'll find an astonishing range of kinds of ways of life.