Justin Marshall has made fundamental contributions to the understanding of both sensory neuroscience and ecology. His major achievements include: the discovery of the world’s most complex colour vision system; the first demonstration of sensitivity to circularly polarised light in any animal; discoveries defining modern visual ecology in both vertebrates and invertebrates; and running the world’s most widely used coral health citizen science program. Marshall has published in leading journals, such as Science, Nature and Current Biology, and generates enormous public interest and awareness. His work regularly features in all media forms, notably including several documentaries with Sir David Attenborough.