By Rebecca Boyle, Inside Science -- When light bulbs colonize our homes, humans get much less sleep. It's an intuitive idea, but a new study measures this effect in a real-life situation for the first time by examining hunter-gatherers in Argentina.
Communities with access to electric lighting have shifted their bedtimes to later in the evening, curtailing a normal night of shuteye.
"When you have access to electricity, you can decide when you turn the lights off, and that resets your biological clock," said Horacio de la Iglesia, a biologist at the University of Washington, in Seattle, who led the study.