Determinants of rate variation in mammalian DNA sequence evolution

L Bromham, A Rambaut, P H Harvey

Research output: Contribution to journalArticlepeer-review

Abstract

Attempts to analyze variation in the rates of molecular evolution among mammalian Lineages have been hampered by paucity of data and by nonindependent comparisons. Using phylogenetically independent comparisons, Ne test three explanations for rate variation which predict correlations between rate variation and generation time, metabolic rate, and body size. Mitochondrial and nuclear genes, protein coding, rRNA, and nontranslated sequences from 61 mammal species representing 14 orders are used to compare the relative rates of sequence evolution. Correlation analyses performed on differences in genetic distance since common origin of each pair against differences in body mass, generation time, and metabolic rate reveal that substitution rate at fourfold degenerate sites in two out of three protein sequences is negatively correlated with generation time. In addition, there is a relationship between the rate of molecular evolution and body size for two nuclear-encoded sequences. No evidence is found for an effect of metabolic rate on rate of sequence evolution. Possible causes of variation in substitution rate between species are discussed.

Original languageEnglish
Pages (from-to)610-621
Number of pages12
JournalJournal of molecular evolution
Volume43
Issue number6
Publication statusPublished - Dec 1996

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