Entomology: Let Sleeping Flies Lie

Do flies sleep? after prodding and tapping fruit flies, measuring their activity with ultrasound and infrared detectors, blasting them with sound waves and monitoring their genes, researchers at the Neurosciences Institute in San Diego have come to a definitive conclusion: the flies actually doze off in slumber patterns that are strikingly similar to those of humans.

Writing in the current issue of Science, the researchers report that the flies are somnolent mainly at night and active during daylight hours: that elderly (33-day-old) flies sleep less and more erratically than younger ones; that fruit flies deprived of sleep must nap longer to recover; that caffeine keeps them awake, and antihistamines make them that drowsy.

Perhaps most significant, many of the fly genes that turn off during sleep and on when the insects are active proved to be identical to those that regulate mammalian slumber. That means researchers can use flies to test potential drugs and genetic treatments for aiding sleep and preventing drowsiness, rather than putting humans in danger.

Now that the tiny insect has demonstrated such sophisticated brain function, another question occurs to neurosciences researcher Paul Shaw: "Does the fruit fly dream?"

--By Leon Jaroff