Charles Darwin must have been a regular at whatever passed for a bar on the HMS Beagle. During the ship's five-week stop at the Galapagos, the scientific superstar-to-be got his kicks from riding the trunk-size tortoises that give the islands their name -- galapago is Spanish for "saddle." Despite the creatures' saddle shape, Darwin complained of often falling off. Maybe they mixed gin-tonics stronger back then.
Darwin also used to enjoy slinging lizards (or, more precisely, marine iguanas) during those high-spirited weeks of September 1835. "I threw one several times as far as I could, into a deep pool left by the retiring tide," the eminent Victorian noted. "And as often as I threw it, it returned." He wasn't impressed by this "singular piece of apparent stupidity."
In between such hilarity, Darwin put in enough fieldwork to substantiate his developing evolutionary theories. His conclusions, published in 1859's "The Origin of Species," made the Galapagos famous.