<p>"The day has past delightfully. Delight itself, however, is a weak term to express the feelings of a naturalist who, for the first time, has wandered by himself in a Brazilian forest."—The Voyage of the Beagle, February 29, 1832</p>

The Atlantic Forest, Carlos Botelho State Park, Brazil

"The day has past delightfully. Delight itself, however, is a weak term to express the feelings of a naturalist who, for the first time, has wandered by himself in a Brazilian forest."—The Voyage of the Beagle, February 29, 1832

Photograph by Luciano Candisani, Minden Pictures

Darwin's First Clues

He was inspired by fossils of armadillos and sloths.

This story appears in the February 2009 issue of National Geographic magazine.
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