Abstract Background Bird genomes have very different compositional structure compared with other warm-blooded animals. The variation in the base skew rules in the vertebrate genomes remains puzzling. but it must relate somehow to large-scale genome evolution. Current research is inclined to relate base skew with mutations and their fixation. https://www.nacrack.com/quick-save-TRAILMASTER-CHALLENGER-200X-UTV-2-SEATER-super-grab/