1. Throughout the latter half of the course you have been introduced to a number of different hominin species along our direct evolutionary line, along with those from some dead-end side branches. These exhibit a number of different trends in the morphology of the hominin cranium over the last 4 million years or more. A major one of these trends is flattening of the face. This simple trend explains many of the characteristics that you can see in our own cranium. For example, if the face of an Archaic Homo sapiens, such as a Neandertal, is just pushed straight back until it is flatter it pushes the teeth back in the mandible and removes the retromolar gap and, if you keep pushing, it removes the space required for the third molar (our disappearing wisdom tooth). Pushing the face back also produces a pointier chin. A second characteristic, our taller, more vaulted cranium, will also naturally result in a more vertical forehead, which will tend to reduce the appearance of a browridge and it will likewise reduce how far our occipital bone appears to protrude. Just these two changes, a flatter face and a taller cranium, can potentially explain many of the morphological differences that we have noted between us and our archaic ancestors and cousins. Can you think of evolutionary explanations for these trends? Any other explanations? Also, if these two trends continued what sort of projections/predictions could we make about our future cranial morphology?
2. Although the Regional Continuity model still has a few proponents and we still need to understand better how DNA works, the current genetic evidence seems to point towards the Complete Replacement model. If this turns out to be the way modern humans came to dominate the planet, try to imagine how this may have occurred from region to region when we met up with the indigenous people, such as, the Neandertals in Europe and, perhaps, Homo erectus in Asia. Do you think these would have been relatively peaceful encounters, with our ancestors just out-competing the locals with improved technologies, or were the locals simply swamped with our greater numbers? Or perhaps it was a more 'pro-active' process with occasional or even frequent acts of violence?
Currently we really don't know much about this process. If we examine modern hunter-gatherers we can see that, while violence is not uncommon, it tends to be more ritualized and full-on genocide is very rare. Among relatively simple hunter-gatherer cultures, warfare is very anti-productive and maladaptive because, since these groups are so small, the consequences for the group as a whole of losing even a few members are very severe. It is not until we start looking at more complex cultures, such as sedentary, urbanized societies that produce their own food that serious warfare becomes common and acts of violence more extreme.