Stronger evidence for relaxed selection than adaptive evolution in high-elevation animal mtDNA.

ABSTRACT: Mitochondrial (mt) genes are the subject of many adaptive hypotheses due to the key role of mitochondria in energy production and metabolism. One widespread adaptive hypothesis is that selection imposed by life at high elevation leads to the rapid fixation of beneficial alleles in mtDNA, reflected in the increased rates of mtDNA evolution documented in many high-elevation species. However, the assumption that fast mtDNA evolution is caused by positive, rather than relaxed purifying selection has rarely been tested. Here, we calculated the d_N/d_S ratio, a metric of nonsynonymous substitution bias, and explicitly tested for relaxed selection in the mtDNA of over 700 species of terrestrial vertebrates, freshwater fishes, and arthropods, with informati

SUBMITTER: Iverson ENK 

PROVIDER: S-EPMC10849488 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature