If you're enjoying this podcast, we would love to tell you about Common Descent.

Common Descent is a podcast about paleontology, evolution, and the history of life on Earth,

hosted by two paleontologists with an unending enthusiasm for the wonders of the world.

Each episode cover science news, followed by a deep dive into a main topic requested by the audience.

Recent episodes of feature topics like eels, hibernation, and fungi.

In addition to the main series, Common Descent also features side projects that explore science

and pop culture, where the host examined the science and movies or speculate on the

hypothetical evolution of fictional monsters.

Listen to Common Descent on Spotify, Apple, or wherever you get your podcasts.

It's a warm, wet world, a little over 500 million years ago in the Cambrian period.

Standing on a rocky shoreline, you take a deep breath and find that the air seems breathable,

but thinner than you're used to. It feels sort of like being at extreme

high altitude in modern times, survivable for a while at least, but not exactly comfortable.

As you gaze inland, you see a barren landscape with no vegetation of any kind. Rock and mud

and shades of black and gray and brown stretch as far as you can see

baking in the afternoon heat. There isn't a hint of green anywhere. Plants haven't gotten a foothold on

land yet. The oxygen slowly building up in the atmosphere and in your lungs is produced almost entirely by microbes.

With so little to see on land, you begin to think that all this period has to offer is biological boredom and ecological emptiness.

But you couldn't be more wrong.

Because the Cambrian world is one of startling evolutionary innovation, if you

know where to find it. As you turn your back to the land and dive beneath the waves instead,

your eyes scanning for movement, you begin to see just how dynamic this world really is.

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