If you want to get from Los Angeles to Seattle, say, you could fly or drive or take a train,

but let's imagine that you need to hoof it. There's more than a thousand miles, so it would

take a couple months to hike. At an average jogging pace of, say, five miles per hour, it would be more than 200 hours

in total. Now imagine doing that, jogging, but almost never stopping to rest with barely any food or

water. How long do you think before the human body simply couldn't take it anymore? This is more or less

what hundreds of species of birds do,

year after year, season after season, on their migratory roots,

and we're not just talking about seabirds that are soaring on thermals across the ocean.

We mean little songbirds, strenuously flapping their wings,

hour after hour, day after day.

How do they do it?

Welcome to the Quanta podcast where we explore the frontiers of fundamental science and math.

I'm Samir Patel, editor-in-chief of Quantum Magazine.

Long-distance migration is one of the most stunning athletic feats of the natural world.

Understanding how birds actually pull it off means getting into some pretty surprising

cellular and molecular properties.

Here to speak with us today about this is Quanta's biology editor Hannah Waters. Welcome, Hannah.

Hello, Samir. Thanks for having me.

We always like to start with the question, what is the big idea? Where are we going with this conversation?

The big idea to me is that this is a continent-spanning global phenomenon of animal migration that can be explained by traits that are microscopic at the subcellular level.

It's really astounding.

Tiniest thing to explain the biggest thing.

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