The nematode Pristionchus pacificus has been established as a model system for modern evolutionary studies. Evolutionary reconstruction of the natural history of organisms requires knowledge about the development, ecology, and phylogeny of species. Mutations are the source of natural variation, hence studies of mutational processes improve the understanding of the natural history of an organism. Mutation accumulation (MA) lines experiments facilitate the study of spontaneous mutation rates over many generations and offer the possibility of inferring calibrated phylogenies for taxa that lack fossil records. In this study, we used the MA lines setup to calculate mutation rates at the level
of the mitochondrial genome and microsatellite loci of the nuclear genome of P. pacificus.
Mitochondrial DNA (mtDNA) evolves rapidly in populations, is usually transmitted
maternally without intermolecular recombination and has therefore been intensively used for phylogeographic studies. The P. pacificus mtDNA is 15; 955 bp in length and contains all the known mitochondrial genes. In the 142nd generation of the 82 MA lines, we found an overall mutation rate of 7.6e-8 per site per generation. The unusual presence of a suppressor transfer RNA for the codon UAA has...