Cellular transcriptomics reveals evolutionary identities of songbird vocal circuits

The cells of songbird motor circuits Birds have complex motor and cognitive abilities that rival or exceed the performance of many mammals, but their brains are organized in a notably different way. Parts of the bird brain have been functionally compared to the mammalian neocortex. However, it is still controversial to what extent these regions are truly homologous with the neocortex or if instead they are examples of evolutionary convergence. Colquittet al. used single-cell sequencing to identify and characterize the major classes of neurons that comprise the song-control system in birds (see the Perspective by Tosches). They found multiple previously unknown neural classes in the bird telencephalon and shed new light on the long-standing controversy regarding the nature of homology between avian and mammalian brains.Science , this issue p.eabd9704 ; see also p.676