A new study of fruit flies may shed light on sleep as an evolutionary tool.

Flies that cannot take to the air respond by sleeping more as they learn to adapt to their flightlessness, according to a study from Washington University School of Medicine in St. Louis. The findings, published May 8 in Science Advances, suggest that sleep may be an evolutionary tool that helps animals adapt to challenging new situations.

“We know that sleep is involved in creativity and insight,” said senior author Paul Shaw, PhD, a professor of neuroscience. “Have you ever slept on a problem, and when you wake up you’ve found the answer? Anxiety keeps people up at night, but if you find yourself in a dangerous environment, or in a situation that you don’t know how to deal with, sleep may be exactly what you need to respond to it effectively.”

Fruit flies’ sleep looks a lot like people’s. Baby flies need a lot of sleep, but as they get older, their need for sleep diminishes. Flies become more alert with caffeine and drowsier with antihistamines. And if you keep a fly awake one day, it will sleep more the next.

These similarities suggest that the sleep habits of flies might shed light on the sleep habits of people. To explore the relationship between challenging circumstances and sleep, Shaw and staff scientist and first author Krishna Melnattur, PhD, took away flies’ ability to fly.

Get the full story at medicine.wustl.edu.