This essay offers a rationale for deploying ecofeminist science fiction stories as object-oriented thought experiments in science and environmental education, with particular reference to developments in genetics and evolutionary biology, and their implications for human (and more-than-human) reproduction and kinship in the period following the determination of the double helical structure of DNA by scientists affiliated with Cambridge University's Cavendish Laboratory in 1953, and the impact of subsequent gene-centric discourses on the biological sciences and the wider culture. The utility and defensibility of this approach is exemplified by reference to two science fiction novels by the late Naomi Mitchison that foreground and anticipate implications of genetic sciences for matters of concern to ecofeminists, including reproductive rights and responsibilities, population control, human relations with the more-than-human, and problematizing gendered (and other) binaries in everyday speech and popular culture.