After nearly five years circumnavigating the globe, the survey ship HMS Beagle returned to England, its young naturalist Charles Darwin carrying notebooks, specimens, and observations from the Galápagos, South America, and beyond. The voyage's finches, fossils, and geological puzzles would occupy Darwin for more than two decades before he published 'On the Origin of Species.'
Darwin had boarded the Beagle in 1831 as a 22-year-old gentleman naturalist, chosen partly for his social class and conversational skills to keep the ship's captain, Robert FitzRoy, company on long stretches at sea. He suffered miserably from seasickness for much of the voyage and, at several points, seriously considered abandoning the expedition entirely.
What he brought home instead reshaped science. Fossils of giant extinct mammals in Argentina, the staggered variations among finches and tortoises on different Galápagos islands, and geological evidence of gradual land uplift all planted seeds of doubt about the fixed, unchanging nature of species that most naturalists of the era assumed.
Darwin didn't publish his theory of natural selection for another 23 years, wary of the religious and social uproar it would cause, and spurred into print only when Alfred Russel Wallace independently arrived at similar ideas. But the return of the Beagle to English shores marks the practical beginning of the intellectual journey that produced one of the most consequential scientific theories in history.
Key people: Charles Darwin, Robert FitzRoy