The rate of DNA evolution: effects of body size and temperature on the molecular clock.

ABSTRACT: Observations that rates of molecular evolution vary widely within and among lineages have cast doubts on the existence of a single "molecular clock." Differences in the timing of evolutionary events estimated from genetic and fossil evidence have raised further questions about the accuracy of molecular clocks. Here, we present a model of nucleotide substitution that combines theory on metabolic rate with the now-classic neutral theory of molecular evolution. The model quantitatively predicts rate heterogeneity and may reconcile differences in molecular- and fossil-estimated dates of evolutionary events. Model predictions are supported by extensive data from mitochondrial and nuclear genomes. By accounting for the effects of body size and temperature on metabolic rate, this model explains h

SUBMITTER: Gillooly JF 

PROVIDER: S-EPMC544068 | biostudies-literature | 2005 Jan

REPOSITORIES: biostudies-literature