For over a decade, researchers have known that the roundworm Caenorhabditis elegans can detect and avoid short-wavelength light, despite lacking eyes and the light-absorbing molecules required for sight. As a graduate student in the Horvitz lab, Nikhil Bhatla proposed an explanation for this ability. He observed that light exposure not only made the worms wriggle away, but it also prompted them to stop eating. This clue led him to a series of studies that suggested that his squirming subjects weren’t seeing the light at all — they were detecting the noxious chemicals it produced, such…
