Baboon’s text is very wide-ranging and I cannot hope to do it justice in a brief reply. Moreover, he covers areas of which I myself am largely ignorant, and makes a number of points with which I agree, so I don’t want to run the risk of provoking a false debate.
That said, there are a number of aspects to his text which are open to criticism, and these are what I want to try to deal with here.
Baboon’s text falls roughly into three parts. In the first, he concentrates on homo erectus, and erectus’ place in the "emergence of the human": his argument is strongly critical of Chris Knight's notion of a "human revolution" some time over the last 1,000,000 years or so, adopting instead a much more gradualist approach. The second part deals with the relationship between prehistoric art, shamanism, and religious belief. It is a good deal more speculative, but this does not make it any less stimulating: speculation is itself a vital part of the scientific endeavour. The third part is the least successful in my view, and constitutes a defence not just of the method of Engels and Henry Lewis Morgan (with which I would agree), but also of their conclusions.
Baboon calls me "something of an admirer of Knight's work". He is quite right and there are two reasons for this: first, I have a great respect for the vast erudition evident in his book Blood Relations; second, and more importantly, he is trying to grapple with what to my mind is the key question of human evolution: what are the evolutionary processes driving the passage of homo from nature to culture, and how do these processes mark us today? One of the most interesting aspects of the book, in my view, is the use of myth in archaic society to try to delve into humanity's deep past. The immense importance of female menstruation and taboos related to blood and fire, and the way that Knight tries to tie this to a selfish-gene analysis of the behavioural adaptations leading to the emergence of modern man is really key to what Knight is trying to get at, and it's a shame that Baboon doesn't really deal with the questions of myth at all (in the original articles, Darmangeat's dismissal out of hand of the importance of myth as a historical source was one of the main objects of my critical assessment of his book).
In this sense, Knight's work is indeed an attempt to build a "theory of everything" and he himself is very explicit about this (you can hear the point mentioned in the podcasted interview with Knight on this website). In these days of academic over-specialisation and the general fragmentation of knowledge, this is no mean achievement.
That said, I can sympathise with Baboon's irritation at Knight's reaction to criticism. I think that he does in fact have some difficulty in integrating not just criticism but even plain questions which do not fit readily into his theoretical schema. To do Knight justice, this is probably a common, and very human failing amongst those who have spent their lives developing and defending a coherent theoretical framework (it's a critique which has been levelled more than once at the ICC, not always unjustly). The difficulty of thinking "outside the box" is by no means limited to Knight.
Baboon takes Knight to task for being a "Social Darwinist", but I think that this is both wrong and misses the point. Knight is certainly a Darwinist, and adheres to the neo-Darwinian synthesis, sometimes known as "selfish gene theory", which is today's general scientific consensus on the process of evolution, but this by no means makes him a social Darwinist. This is a vital distinction. Darwinism describes the process of evolution, driven by natural selection and the competition between genes, and therefore between individuals, to reproduce; social Darwinism is an attempt (largely and rightly discredited today), to transpose Darwinian principles into human society and thereby to justify the exploitation inherent in capitalism as a form of "the survival of the fittest". Hence Joan Gero's critique of Knight for seeing women as "manipulative" - which Baboon cites approvingly from my original article - is simply meaningless since, to be brief, it attributes intentionality to the evolutionary process, which has none. To say that, in every species, males and females compete for reproductive success, has no moral implications: it is merely a statement of fact, and in different species it leads to different behavioural types ranging from extreme female domination (the female praying mantis eats her partner) to extreme male domination (lions for example) with every possible nuance in between. Taking our closest cousins on the evolutionary tree as a starting point, Knight asks how evolution led us from the ultra-competitive male-dominated society of the apes, to human society based on cooperation and solidarity: it is precisely within this process that human consciousness emerges and that human intentionality replaces the blind movement of evolution. Moreover, the cultural phenomenon of what Knight calls the "sex strike" is by no means a matter of "manipulation" by women, since it is something in which all society participates. The fact that Gero transposes the prejudices of a 20th century feminist onto archaic humanity, and better still onto prehuman apes, merely demonstrates her own superficiality.
I think there is also a danger in Baboon's statement at the beginning of his text that the investigation of man's origins "shouldn't be an academic exercise but one that reinforces proletarian political and historical views against those of the bourgeoisie and strengthens our perspective of communism". This implies that what can only be the result of a scientific investigation should be determined by our political goals as communists. To accept such an idea runs counter to Engels' insistence on the "ruthless disinterestedness" of science, and undermines scientific endeavour as such.
Nonetheless, Baboon's objections to Knight's timescale are perfectly valid, and I confess to having my doubts as to the appropriateness of the term "revolution" for an evolutionary process which must have lasted several hundreds of thousands of years. The question of when, how and why human symbolic reasoning and consciousness emerged is enormously complex, still more because unequivocal evidence is so hard to come by. Baboon makes some convincing points about the emergence of culture in homo erectus, but is there any reason why Knight's model should not have its timescale extended by a million years or so?
The existence of apparently altruistic behaviour in animals has always been one of the great problems that selfish gene theory has had to confront. In general, it can be explained by genetic proximity: the more closely related animals are, the more likely they are to display altruism towards each other. Otherwise, the law of nature is competition, for both resources and the chance to reproduce. The question posed by the appearance of humanity is how this process of competition reversed itself so to speak, so that out of selfish-gene competition there emerged a species for which solidarity and cooperation are not just necessary for survival, but an inbuilt psychological need. Baboon in my view does not really try to answer this key question, and towards the end of his text he seems to want to solve the problem by making human evolution a conscious choice. Otherwise, how are we to construe this statement: "as far as the anatomical details are concerned we can fill in some elements of Engel's ape/homo transition to a fully bipedal species: apart from the great advantage of the better opposability of the fingers and thumbs , the foot with 22 bones in it had to rearrange itself. The pelvis, spine, shoulder, arms, ribcage, neck and chest also had to be modified. Even here at this early stage - especially here at this early stage - there is more than simple adaptations to environment and circumstances. These too are "history-making" humans. There's no other way to describe their survival and persistence against all the odds." Quite apart from the fact that adaptation driven by natural selection is anything but simple (we need only look at the bewildering diversity of its results in nature!), is Baboon really trying to suggest here that human beings "make history" by directing their own evolution from the apes?
To conclude, much as I value Baboon's text - from which I have learnt a good deal - I continue to think that Knight's approach is fundamentally valid: his model may or may not be correct, but he is asking the right questions in the right way, and that is the crucial thing.