The author of the review, D. Currie Hall, makes some very interesting point regarding the nature of biolinguistics. On another occasion, I will discuss his statement to the effect that "biolinguistics is a relatively new endeavour". Today, I want to focus on the question he raises half-way through the review: "What does it mean to pursue a biolinguistic approach to phonology, or to language in general?" Daniel is right in saying that "In one sense, it means that the field of inquiry becomes broader." As he writes, "Some phonological patterns find an explanation in the interface conditions of syntax, others in the neurophysiological underpinnings of mammalian auditory perception. A successful biophonologist must know enough about both of these things, and many others, to be able to make reasonable inferences about what each of them contributes."
On the other hand, "In another sense, the central object of study becomes much smaller. If some of phonology is really syntax, and some of it is really phonetics, then relatively little of phonology is phonology." This is where biolinguistics meets (some kind of) minimalism, and it is also where biolinguistics really departs from philology-oriented projects (among which, many modern formal/theoretical studies).
Biolinguistics done seriously (i.e., with an equal dose of 'ling' and 'bio') really calls for a redefinition of the subject matter of grammar (syntax, phonology, semantics, etc).