Repetitive DNA profiles reveal evidence of rapid genome evolution and reflect species boundaries in ground beetles

The overall structure and organization of genomes holds layers of information informative to studies on evolution. However, studying the entire architecture of genomes can be prohibitively expensive. We investigate whether copy number variation profiles of ribosomal can serve as a simple measure of variation in a single component of the genome that might correlate with more complex biological phenomena. We find notable variation in rDNA profiles that strongly correlates with species boundaries and provides evidence of rapid genome evolution among closely related species that is not apparent from studying traditional sources of molecular data. Our findings suggest this simple measure may be a useful tool in studies on species delimitation and genome evolution.