Corballis assembles evidence in favor of the theory that sophisticated gestural language (as contrasted to "proto-language") preceded spoken language. Certainly, this makes great intuitive sense, since there is a steady increase over time in genus homo in that part of the brain which controls language, whether it be gestural or vocal, and this preceded the evolution of fine vocal capabilities. Moreover, it is intuitive that gestures come more naturally, and with use would become more expressive and "conventionalized". On the other hand, while tool making became more sophisticated with the Acheulian technology, found in sites as old as 1.4 million years ago, the real flowering of tools, art, religion was more likely around 50,000 years ago, when the capability for fine vocalization already existed, suggesting, as many scientists have concluded, that there may have been a major leap forward at that time in speech and conceptualization (cf. Turner, Mark and Gilles Fauconnier: "The Way We Think"). So how worthwhile is "From Hand to Mouth"? Much of the writing is good, I enjoy Corballis' many wisecracks, and he examines what is known in the many relevant subject areas. Although he tries to be fair, he can be sloppy. While he cites Jared Diamond's "Third Chimpanzee", he repeats the conclusions some scientist's have drawn from the development of the numerous "creole's", without mentioning, as Diamond does, the possible flaw in reaching such conclusions. At other times, he makes assumptions without realizing he is doing so. Thus, in mammals, right limbs are controlled by the left side of the brain, and visa versa. This is not an inevitable specialization as Corballis thinks, but may owe more to how evolution frequently works: if designed from scratch, it might be more efficient to have both sets of limbs controlled from the same brain area. The Corballis chapter on right brain vs left brain suffers very much from lack of reference to the work of a noted neurologist, reported in a great book: , "Phantoms in the Brain" by Ramachandran. Incidentally, the role of the FOXP2 gene in speech (see earlier reviewer) is quite controversial. "From Hand to Mouth" is definitely worthwhile, but a better book on the subject will undoubtedly be written.