Martin Brasier's work spanned almost the entire geological column, but the origin of animals and the nature of the Cambrian explosion were areas of particular interest to him. Martin adopted a holistic approach to the study of these topics that considered the interplay between multiple geological and biological phenomena and he sought to interpret the fossil record within the broad context of geological, biogeochemical and ecological changes in the Earth system. Here we summarize Martin's main contributions to this area of research and assess the impact of his findings on the development of this field.