Our alarm clocks may spring forward on March 9, but our biological clocks may take longer to adjust. That’s because our internal clocks are so tightly wound to many physiological and behavioral processes. Researchers have learned that circadian rhythms–the 24-hour cycles that keep our bodies on time–are involved in sleep, weight gain, mood disorders, and a variety of diseases. Now, they’ve made remarkable strides in identifying genes and neural pathways involved in regulating our internal clocks. Building on this bed of research could lead to new treatments for insomnia, jet lag, depression, obesity, and other disorders.