A novel system developed by Janelia researchers that chases larval zebrafish around an arena with predator robots is enabling scientists to understand how these days-old fish quickly learn in the real world. Larval zebrafish are an invaluable tool for neuroscientists, who use the tiny, transparent fish to probe how the brain controls behavior, but it’s been difficult for scientists to study learning in these developing vertebrates – an important part of understanding how the brain works.