Transitions between modes of sex-determination in a changing world

Sex-determination controls the largest variation within animals—the division into males and females. While the different systems of sex-determination—involving genetic or environmental control—are fairly well understood, transitions between these systems remain enigmatic in evolutionary biology. We will address this gap by revealing the molecular change required to transition between systems, using one of only two known lizard species exhibiting both genetic and temperature control of offspring sex. This knowledge will have important implications for species conservation, facilitating predictions of highly biased sex ratios under climate change, plus potential commercial applications for species where production of one sex is favoured.