To reply to a digest, insert the relevant message header; don't reply to the digest header ------------------------------------------------------------- Episode 2 continued the strong evolutionary thread of episode 1 and the importance of natural selection was emphasized as it showed Homo habilis, Homo rudolfensis and Paranthropus boisei in direct competition with each other. I have decided to ignore the silliness of some of the acting, the occasional corny costumes and the odd role Winston makes for himself, strolling through the African savanna 2mya; if you do this, then what is left is very rewarding indeed. Here are some highlights from this evening's broadcast: 1. We often think of early humans having to be wary of lions, but the program depicts - through digitally-created images - sabre-toothed tigers and other megafauna now extinct which brought home to me how perilous life was. 2. The leader of the habilis band is depicted as being slain by a lion and the difficulty it causes the survivors in replacing him - although it was less for the quick-witted habilis with their less specialized body shape and sexual dimorphism than for the less opportunist bosei. 3. A lion is also shown eating a freshly-killed eland carcass and vultures are mentioned (circling vultures led the observant habilis to the meat). The lion and the vultures, no matter how much flesh they took, still left the bone marrow and habilis is depicted smashing open the large bones and slurping up the marrow. 4. All in all there is much more on diet in this second episode. The program gives us the usual story: eating meat > larger brains > smarter species > 'the new world of ideas'. And one big idea was the creation and adaptive use of stone tools for the first time; this accelerated and magnified, in an iterative feedback, the way meat eating fostered intelligence and how intelligence made meat-eating easier. (Habilis is a favorite of mine!) To me, it is ideas, not diet, not exercise that lies at the real heart of evolutionary fitness; it is just that our physical health and dietary well-being are presently in such desperate need of returning to our Pleistocene roots that we focus most on them, But we must never neglect ideas and social relationships, otherwise we will go the way of the bosei. 5. For the bosei, it mentions their consumption of termites; I understood that termites were being presented as a staple, not just a novelty to the bosei or a novelty to cause us, the viewers, to elicit 'Yuk!'. 6. Quite a bit on teeth here, too. We hear a lot about bosei's huge jaw muscles and massive molars used to consume the plentiful but fibrous reeds and roots. This continues to puzzle me as I would have thought that anyone eating roots would also be chewing grains of soil and sand and tiny pebbles and that this would wear away teeth far more than would eating meat and marrow. 7. Once again, nice depictions of climate change and how it drove natural selection. This time it shows how the specialized bosei were highly successful while the climate remained stable and continued to provide their staples in abundance. But climate change transformed the vegetation and the specialized bosei succumbed while the dietary 'jack of all trades' habilis was adaptable and could swing easily from eating the meat of one animal (which, like bosei, was declining in response to the climate change) to eating meat of another animal (whose population thrived in the emerging climate-created niche). Come to think of it - aren't we bringing on climate change ourselves now, in the 21st century! 8. Habilis are depicted as hyper-active little imps operating in groups of around 20 in contrast to the lumbering, slothful, predominantly- vegetarian bosei ('these lovely creatures' as the narrator calls them) in their groups of 5-8. And habilis were the survivors, so we should be looking to them rather than bosei or rudolfensis for models today. 9. Bosei, rudolfensis and habilis are all depicted as operating in families: the habilis hunt in groups, each defends themselves cooperatively against attack or predation; grooming and play are important in bonding and in practicing and reinforcing the effectiveness of cooperation. Next week: Homo ergaster. Keith ----------------------------------------------------------------- The FAQ for Evolutionary Fitness is at http://www.evfit.com/faq.htm To unsubscribe from the list send an e-mail to [log in to unmask] with the words SIGNOFF EVOLUTIONARY-FITNESS in the _body_ of the e-mail.