Here's a couple of quotes I have always regarded as justifying my "discovery" of the Pack:
“If there’s one thing of which we can be pretty certain, it is that during the last million years there was a lot more going on in human evolution than we have yet been able to discern.”"the fossils and artefacts are sparse nonetheless relative to the number and variety of peoples from whom they derive, and the intricacies of their lives. It is entirely possible that pivotal events and populations have disappeared without any trace, and that we will never have direct knowledge of them. … So there is room for speculation …"
Ian Tattersall: Becoming human: Evolution and human uniqueness, p145
Colin Tudge: The day before yesterday. London: Jonathan Cape, p232
The recent discovery of Flores Man emphasizes the truth of these remarks.
But the point of the Pack is not that they might exist. The point is that it allows us to explore the whole question of what it means to be human. I'm not a big fan of the human-animal dichotomy — we are animals (which is why I'm always careful to talk about non-human animals when discussing creatures other than ourselves). But although I take a keen interest in the cognitive abilities of non-human animals, and believe there's no defining feature that categorically distinguishes us from all other animals, it's foolish to pretend there's no difference. The difference may be quantitative rather than qualitative, but it assuredly exists.
The characteristics of the Pack were chosen carefully, to explore some of the abilities humans have and some of the things we have lost. Hair, for example. The hairlessness of humans is a feature that has been much discussed by scientists — why did we lose most of our body hair? What's the advantage? Or perhaps, was there an advantage to having hair that no longer existed when we developed some other ability?
But no single feature develops in isolation; features interact with each other. The development, or loss, of one feature can mean that some other feature is needed, or no longer needed. So we must ask ourselves, what features are related to having hair?
Hair is related to grooming, and grooming is associated with social bonding, and the increase in brain size among humans is widely thought to reflect the social demands of cooperative living.
But grooming has its limits. Talking allows us to greatly expand the number of people with whom we can simultaneously interact. Talking, it has been suggested, allowed us to significantly increase the size of our social group. And of course, made grooming no longer necessary, which would have reduced any need for hair.