This is Origin Stories, the Leaky Foundation podcast. I'm Meredith Johnson.

All around the world, people tell stories about the moon and its power over human behavior,

from tales of goddesses and gods to folk wisdom about fertility and farming, to legends about

monsters. The full moon is especially important and symbolic. In stories, it's when

werewolves transform, and people behave more strangely.

Our connection with the moon isn't the type of thing you might think of investigating

scientifically. But on today's episode, we'll talk with a scientist whose research shows

that the moon has a powerful and scientifically quantifiable impact on one of the defining traits of human life.

Sleep is so fundamental to our existence as humans that we spend a third of our lives doing it.

And researchers are still working to find out why.

Yeah, okay.

Okay, so my name is Sorasio de la Iglesia and I'm a professor of the Department of Biology at the University of Washington.

Dr. Della Iglesia is a leaky foundation grantee and a neurobiologist who studies circadian rhythms.

Circadian rhythms are a kind of internal clock we all have,

a clock that drives and regulates the processes in our bodies that run on a

rhythmic cycle. And we have a lot of those, the menstrual cycle, body temperature cycles.

The best example is the sleep-wake cycle, this alternation that we have between consciousness

and unconsciousness is driven by a biological clock that tells your brain

this is a good time to be sleeping and it's not a good time to be sleeping and you should be awake.

Sleep is a strange behavior if you think about it.

For humans, every 24 hours or so, our internal clock goes off, and we slip into unconsciousness

for about eight hours. We mostly just lie there, and we have very little awareness of our

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