We tested the metabolic rate hypothesis (whereby rates of mtDNA evolution are postulated to be mediated primarily by
mutagenic by-products of respiration) by examining whether mass-specific metabolic rate was correlated with root-to-tip
distance on a set of mtDNA trees for the springtail Cryptopygus antarcticus travei from sub-Antarctic Marion Island. Using
Bayesian analyses and a novel application of the comparative phylogenetic method, we did not find significant evidence
that contemporary metabolic rates directly correlate with mutation rate (i.e., root-to-tip distance) once the underlying
phylogeny is taken into account. However, we did find significant evidence that metabolic rate is dependent on the
underlying mtDNA tree, or in other words, lineages with related mtDNA also have similar metabolic rates. We anticipate
that future analyses which apply this methodology to datasets with longer sequences, more taxa, or greater variability will
have more power to detect a significant direct correlation between metabolic rate and mutation rate. We conclude with
suggestions for future analyses that would extend the preliminary approach applied here, in particular highlighting ways to
tease apart oxidative stress effects from the effects of population size and/or selection coefficients operating on the
molecular evolutionary rate.
McGaughran, A., & Holland, B. R. (2010). Testing the Effect of Metabolic Rate on DNA Variability at the Intra-Specific Level. Plos One, 5(3), e9686. doi: 10.1371/journal.pone.0009686
2010 McGaughran, Holland. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: AM was supported by a New Zealand Tertiary Education Commission Top Achievers Doctoral Scholarship. The funders had no role in study design, data
collection and analysis, decision to publish, or preparation of the manuscript.