Bipedalism in the earliest hominid specimens is always accompanied by the reduction of projecting canine teeth. Body size is smaller than chimpanzees or humans, but molar teeth are markedly larger. Use of a pointed stick for defensive purposes on the one hand, and digging for USOs on the other, may be why bipedalism was selected for. Passing such learned behavior to the next generation may have played a role in selecting for language.

This book presents a survey of the molecular basis for the genetic control of living organisms and their evolution. The authors consider four dimensions of control over what shapes life forms: genetic, epigenetic, behavioral, and symbolic/cultural. They pay particular attention to the epigenetic realm, and they defend a view recognizing the genetic incorporation of acquired characteristics – a neo-Lamarckian tack.