Stereotypical images of human prehistory projected by popular media, which frequently consign female hominids to a subordinate role in palaeolithic society, are reinforced by ideas of 'Man the Hunter' as a leading selection pressure in our evolution. Yet, an overwhelming consensus among scholars has long since rejected these deterministic notions as little more than clichés which serve to obscure the real significance of sexual differences during human evolution and the importance of gender relations in the rise of a hominid economy and society. This article presents the case that specific issues which relate directly to sex and gender were formative influences which directed human evolution. Accordingly, sexual dimorphism in primates is reviewed in relation to human evolution: the long-term reduction of major differences in the body weight and size of males and females is seen in terms of an emerging culturally directed foraging strategy 2 million years ago. The economic importance, and frequent superiority of women, in extant foraging societies is considered in relation to genderized economic roles in prehistory. The absence of women hunters in these societies is taken as evidence that a sexual division of labour was a major precipitating factor in the evolution of our species but not a source of modern gender-based inequalities.