ALT A news article illustrated with an underwater scene depicting a large ichthyosaur accompanied by two large sharks, with sunlight streaming through the water's surface, illuminating the creatures and the surrounding aquatic vegetation.

ALT Schematic diagram showing examples of punctuated change across biological change. In the centre, four different empirical patterns of punctuated change (ecological dynamics, a fitness landscape, phenotypic space and genotype space, from top to bottom) with graph showing example data linked to each one: (top right) evolution of ecosystem organization in different modules during the Miocene; (top left) fitness change in a virus; (bottom left) evolution of E. coli cell size; (bottom right) clonal evolution in cancer cells.