It sounds great, Andy and Art! But... What about any Homo sapiens who does not (whether fertile or not) HAVE grandchildren? They can't be a member of the species because they did not achieve this criterion. There have been fertile couples who have had children but, due various reasons, had no grandchild born to their offspring. These people, also, would not be recognizable as Homo sapiens, having failed the "true" test of a species. Is there some way to modify this idea to make it more applicable? Maybe the test for Equus sp. won't work with us. Aloha, makuabob (a.k.a. Bob Dayle) ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com