Genomic evolution of birds

The genomic evolution of birds has come under scrutiny since the advent of rapid DNA sequencing, as birds have the smallest genomes of the amniotes despite acquiring highly derived phenotypic traits. Whereas mammalian and reptilian genomes range between 1.0 and 8.2 giga base pairs (Gb), avian genomes have sizes between 0.91 Gb (black-chinned hummingbird, Archilochus alexandri) and 1.3 Gb (common ostrich, Struthio camelus).

Source: Wikipedia — Genomic evolution of birds (CC BY-SA 4.0)