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.

You're in Siberia, but on this summer day, you don't need a coat. These are the Al-Tai

mountains, close to where present-day Russia forms a corner with Kazakhstan, Mongolia, and China.

Today, lush river valleys cut between rocky ridges dotted with spruce trees.

Sixty thousand years ago, the landscape looked similar.

Earth was enjoying a relatively warm period between the two ice ages of the Pleistocene epoch.

Chipmunks dart under the shrubs as a brown bear ambles along the stream.

Above you, a few horned ibecks peer down from crags in a limestone cliff.

Eventually, you spot some folks who look like you. Well, more like you than the other forest creatures.

Not sure whether they'll perceive you as friend or foe,

you crouch behind some ferns and watch from afar.

It seems like these humans are having a picnic sprawled on animal furs

just downhill from a cave.

Then you realize they're at work, crafting stone tools.

A few adults gracefully hammer one rock against another, knocking off finger-length knife-like pieces.

...