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Forests, Forest Forest, Forest, Forest, Forest.

Hi, I'm Paul Mackey and I play POS. 4404 4.

Hi, I'm Paul Mackey, and I play Pan in Forest 404.

And this is the third in our series of pod talks,

which explore the big ideas behind the world of the drama.

Hopefully, you've just heard episode three,

where Pan meets Guggy, the brain technician in the depths of fume town,

a city that runs 24-7 without direct sunlight. So our pod talk this week is about circadian rhythms.

Have you ever thought about night and day? Like really thought about it? Herman Vinen has thought

about it loads. He's a chronobiologist at Southampton University.

As a biologist who looks at solar and lunar-related rhythms.

Do humans and other species automatically keep time

using some kind of internal clock?

Can you live without it?

To tell you more, here's Herman.

As you're listening to my voice, your response may actually be different depending on what the time of day is.

If you're listening to this late in the day, just before you go to bed, when you're really tired,

you might not be that pleased to hear me. You might not pay attention that easily. If I'm the first thing you hear

in the morning, your body might be ready to pay attention. You might be closer to your peak

cognitive strengths, and you might actually be excited to hear what I have to say. And part of that difference depends on an internal typekeeping system

that all humans share with many other organisms on Earth

...