A map showing stonechats from different parts of the world. Breeding range (yellow) and wintering range (orange) is shown for migrants, year-round range (blue) is shown for residents. The birds differ in their annual cycle, in their migration (shown by black arrows), and in aspects of genes that time their annual cycle. Some of the birds were hand-raised; from Justen et al. 2022, https://www.nature.com/articles/s41598-022-11158-z