The Right period for a Siesta

Drosophila melanogaster has a broad geographic range. Daily activity in this species exhibits seasonality such that midday rest expands on long warm days, possibly to avoid desiccation. Comparative analyses show that temperature-dependent control of this behavior is partly linked to patterns of per mRNA splicing that are absent in Drosophila yakuba, a related species native to warmer climates with little seasonal change.