2016-10-26T14:24:38Z (GMT) by
Geographic trends in Carcharocles megalodon tooth size. A, Tooth size by latitude. The dashed line represents best-fit linear regression model. Black dots represent the middle Miocene (MM) samples, grey dots the late Miocene (LM) samples, and white dots the Pliocene (P) samples. B, Boxplot showing tooth size by hemisphere. C, Boxplot showing tooth size by ocean. D, Tooth size by absolute latitude through time. E, Boxplots showing tooth size by hemisphere through time. F, Boxplots showing tooth size by oceanic region through time.