Cracking the code: Genome sequencing reveals why songbirds are larger in colder climates

Scientists have unlocked the genetic basis underlying the remarkable variation in body size observed in song sparrows, one of North America's most familiar and beloved songbirds. This discovery also provides insights into this species' capacity to adapt to the challenges of climate change. The study used genomic sequencing to successfully pinpoint eight genetic variants, or DNA mutations, largely responsible for the nearly threefold difference in body size observed across the song sparrow range from Mexico to Alaska.