Emily Kwong (host, with guest Nell Greenfield‑Boyce also speaking within these segments)

Hey.

You don't want to talk about pumpkin spice today?

I mean, it's fine in moderation, you know, but like when I think about autumn, I think about real pumpkins and, you know, the leaves and whatever.

But mainly, actually, I think about birds.

The birds.

Yes.

This is their time to migrate.

Right.

There's a lot going south for the winter right now.

Yeah, a lot.

Like every night, hundreds of millions of them are taking to the air.

And like, we don't really notice because this is happening in the dark at night while we're sleeping.

But like huge numbers of birds are flying overhead.

I hear them in the morning when they're on trees.

But why do they fly at night?

Well, I mean, what I've been told is that there's fewer predators and that the air is cooler.

It's more stable.

And plus, you know, when they navigate, they use the moon and the stars.

But that's actually kind of a problem in some ways, because it turns out that means they can be drawn to artificial lights like the kind humans put around buildings.

And so when they come down to rest and refuel in the morning, they can encounter something that they have not been prepared for by evolution.