John, I've always associated "Y-Adam" with the first anatomical human beings (homo sapiens sapiens) which emerged from the archaic homo sapiens about 200,000 years ago. I like the clarity of associating the symbolic first human person with the first species of human beings. The name Adam does not represent subspecies of the human race. Perhaps the term "pre-Adam" could be used for the subspecies. Lee The latest YFull experimental tree estimates Y-DNA Adam at around 234,900 years ago, Over time there have different ways of defining "human". I don't know myself what is the best definition. It could be development of full bipedal walking, or tool use, or speech, or building dwellings, or when wives became boss of the family, but perhaps some would argue that even some magpies and chimpanzees can do all of these things. So then you have to define each aspect, like defining a dwelling as being a minimum of 3 rooms, with attached garage, wide screen TV, and A beer fridge. I will leave it to others to resolve these tricky definitions. John.