Kathy Schick and Nicholas Toth are a couple of archaeologists whose main interest is ancient technology and what it can tell us about how we evolved. What is unusual about their approach is that, with their colleagues, they have carried out extensive experiments to discover what is actually involved in the production of tools by making and using them themselves. However, their very readable book is not concerned just with the development of toolmaking; it provides a general overview of human evolution that could be used as an introduction to the subject by a reader who knew little about it.
They provide an interesting review of how far people in earlier historical periods were aware of prehistory. Classical writers sometimes referred to an earlier bronze or copper age. This may have been mythological, but knowledge of stone tools goes back at least as far as the Middle Ages and mystical or occult significance was sometimes attached to them. However, it took a long time for people to form any idea of the antiquity of these artifacts. A British country squire, John Frere, at the end of the eighteenth century was one of the earliest to do this. Presumably belief in the literal truth of Scripture delayed recognition of human antiquity, although the authors don't make this connection.
Even when serious archaeology began, a source of erroneous conclusions was the idea that our earliest bipedal ancestors must necessarily have used tools. Tools were planted by the hoaxer (or hoaxers) at the Piltdown site to make it look more convincing. Even Raymond Dart, who discovered the Taung baby, may have made this mistake. He thought he had found tools and evidence of weapons associated with australopithecines, and this led to the view, popularized by the playwright and author Robert Ardrey, that our ancestors were bloodthirsty predators—"killer apes". In fact, it's still uncertain whether the australopithecines made any tools; Schick and Toth are doubtful about this.
Their experiments in toolmaking are described clearly, with plentiful illustrations. Making stone tools is quite a dangerous occupation, and there must have been numerous injuries among our ancestors. A few users of stone tools still exist, and a group of archaeologists, including the authors, went to the highlands of New Guinea to see how it's done. The tribesman make more sophisticated tools than those used by early hominids but the early stages of the process seem to be much the same, which encourages the authors to feel confident that their ideas are on the right lines.
Schick, Toth, and their colleagues didn't just make stone tools; they used them too, testing their effectiveness for butchery on a wide range of dead animals, including elephants (which we are assured died a natural death); to their surprise these large animals proved quite easy to cut up; the stone knives cut the tough hide without difficulty. Stone tools also proved effective for breaking open big bones to get at the marrow. This is taken to support the view that our early ancestors were probably scavengers rather than hunters. Microscopic examination of animal bones from ancient sites seems to agree with this idea. It can also be deduced that, by two million years ago, hominids were becoming predominantly right-handed. These details may seem to be rather a lot to extract from fairly scanty material, but Schick and Toth explain their reasoning pretty convincingly.
One of the most puzzling features in human evolution is the length of time during which anatomically modern humans apparently failed to make any technological advance. Why did it take our direct ancestors about 60,000 years to suddenly start making much more sophisticated artifacts than their Neanderthal contemporaries? Four possible explanations are suggested here. The early anatomically modern humans may not have possessed truly modern brains; they may in fact have been making more sophisticated artifacts before 40,000 years ago but these haven't been preserved; accumulating cultural knowledge may have finally crossed a critical threshold; or it may have been the development of language that permitted the change. Schick and Toth don't come down in favour of any of these views particularly.
Their book presents a balanced view of human evolution, generally avoiding giving the impression that progress towards our present technological civilization was inevitable. The authors seem to have a soft spot for the robust australopithecines, whose disappearance from the scene they regret.