The Cryogenian and Ediacaran were an interval of great environmental upheaval, including severe glaciations (the Sturtian and Marinoan, which may have been global in extent, and the Gaskiers); extreme perturbations of the global carbon cycle; and ventilation of the deep oceans with oxygen. All of these events have been cited as potential triggers for the origin of animals. Love et al.3 add to the evidence of early animal life with their identification of 24-ipc in rocks older than 635 million years. The thickness of the orange line indicates the relative abundance of the 24-ipc biomarker at different times. Numbers indicate time in millions of years ago; not to scale.