Amplitudes of orbitally induced climatic cycles and patterns of hominin speciation

► Amplitudes of the precession, obliquity, and eccentricity cycles over the past 5 ma. ► Are tested for significant relationships with hominin speciation and extinction. ► All three components show significant associations with speciation events. ► Only the obliquity cycle shows a significant association with extinction events. ► Climatic change prompts speciation; competition prompts extinction.