Genetic drift and mutational hazard in the evolution of salamander genomic gigantism

The total amount of non-coding DNA (i.e. DNA that does not encode genes or regulation of genes) varies across species. Although non-coding DNA does not encode genes, it still impacts the biology of organisms. Numerous hypotheses have been proposed for why some organisms have so much more DNA than others. Among vertebrates, salamanders have some of the very largest genomes. We used these data as part of a broader study to understand why salamanders have accumulated so much non-coding DNA.