We learn why all mammals today, from humans to bats, have five fingers or fewer.

Why We Only Have Ten Toes (It's a Long Story) Eons

Premiered February 23, 2022
Why We Only Have Ten Toes (It's a Long Story)

Today, all mammals from humans to bats have five fingers or fewer. Yes, even whales, whose finger bones are hidden in their fins. Birds have four or fewer and amphibians get the best of both worlds, often having four digits on their “hands” and five on their “feet.” But no species of vertebrates have more than five digits, let alone eight!

About the Program

Eons

Join hosts Michelle Barboza-Ramirez, Kallie Moore, and Blake de Pastino as they take you on a journey through the history of life on Earth. From the dawn of life in the Archaean Eon through the Mesozoic Era — the so-called “Age of Dinosaurs” -- right up to the end of the most recent Ice Age.

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