In many places, tree squirrels are extra busy these days. It’s time for them to collect nuts to prepare for winter! So we’re heading to a squirrel-themed adventure course and practicing a few of the skills they use to survive: gathering nuts, traveling in trees, and speaking like a squirrel. We’ll also learn about how squirrels evolved, and hear about some of their surprising relatives.

Plus, a mystery sound and a moment of um: what chemical in apples mixes with oxygen to turn brown?

You can support the show at brainson.org/donate or check out our merch (including the Brains On book) at brainson.org/shop

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