Of Epistemes and Insects: How Drosophila and Butterflies Shape Our Understanding of Radiation Risk

This paper explores the complexities of extrapolating insect data to understand nuclear exposure effects on humans. Within radiation research, animal studies are invaluable tools for understanding biological effects of radiation exposure. However, data are often employed selectively, exposing unsettled science in extrapolating animal data to human radiation effects. Here we focus on our understanding of the genetic effects of radiation exposure, and how the debates about the long-term effects on humans were molded by research carried out on the model organism known as Drosophila; disagreements among scientists occurred within the constraints of research on this model organism, creating what we see as a possible Drosophila bias. By tracing how Drosophila became the dominant model organism for radiation genetics, we show how this choice created an epistemic framework that often dismissed contradictory evidence from other organisms, including the more recent Lepidoptera data from Fukushima. Even when animal studies demonstrate harm, they are often dismissed due to the belief-and some of the science-of human exceptionalism: that humans are intrinsically more resilient than animals. In this work, we consider Michel Foucault's ideas on epistemes as they apply to human exceptionalism in the context of radiation effects, mutation, and harm. By examining these two cases genealogically, we demonstrate how Drosophila's dominance established frameworks of population resilience that persist to this day, leading to the dismissal of contradictory butterfly findings as inconsistent with "conventional understanding" rather than as challenges to what counts as legitimate evidence in radiation biology.