Elements R1 and R2 are subject to the same recombinational forces that give rise to the concerted evolution of the rDNA units. Molecular phylogenetic analysis of elements from 16 Drosophila species suggests these elements have been stable components of the rDNA locus for the 50-70 million year history of the Drosophila genus.
Elements R1 and R2 are subject to the same recombinational forces that give rise to the concerted evolution of the rDNA units. Molecular phylogenetic analysis of elements from 16 Drosophila species suggests these elements have been stable components of the rDNA locus for the 50-70 million year history of the Drosophila genus.