Cheetahs have a low genetic diversity – and are therefore poorly equipped to adapt to changing environmental conditions. Nevertheless, the animals display remarkable flexibility: over the course of their lives, male cheetahs might transform from roaming, slim ‘floaters’ into territorial, bolder and more aggressive males. A study by the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) demonstrates that these phenotypic transformations are accompanied by extensive changes in DNA methylation.