Baby birds have sleep patterns similar to baby mammals, and their sleep changes in the same way when growing up. This is what a biologists found out working with barn owls in the wild. The team also discovered that this change in sleep was strongly correlated with the expression of a gene involved in producing dark, melanic feather spots, a trait known to covary with behavioral and physiological traits in adult owls. These findings raise the intriguing possibility that sleep-related developmental processes in the brain contribute to the link between melanism and other traits observed in adult barn owls and other animals.