The chapters in this part of the volume reflect a movement in the late 1990s away from a focus on the genetic evolution of the innate Language Acquisition Device towards accounts invoking cultural and linguistic evolution as well. This is not to deny that the human linguistic capacity evolved biologically, but to acknowledge that such evolution was slow and complicatedly entangled with other aspects of human evolution. The whole part is neatly sandwiched by its first and last chapters, contributed by generative linguists. The first of these argues against narrowly biological adaptationist accounts of language evolution, and the last (complementarily but quite independently, as it happens) casts its contribution to language evolution research in the form of a clearly historical exercise in linguistic reconstruction. The chapters in the middle of this sandwich are no less meaty, many of them setting out on a complementary quest for accounts of how languages could have evolved relatively rapidly into their particular complex modern shapes by nonbiological mechanisms, within a relatively static biological frame of reference.

Several themes connect the chapters in this part, reflecting the general movement just described. These themes are:

• Complex innate principles of the language faculty, such as subjacency, cannot be accounted for by mechanisms of adaptive biological evolution (Lightfoot, Newmeyer).

• More generally, certain features of grammar were or are nonadaptive (Carstairs-McCarthy, Wray).

• Central features of syntactic structure are exaptations of preexisting nonsyntactic structure (Carstairs-McCarthy, Bickerton).