Emotion seemed to fuel plenty of sighs by Humphrey Bogart's character Rick (right) in the 1942 film classic Casablanca, and even Rick's good friend Sam, played by actor Dooley Wilson, couldn't console him. Archive Photos/Getty Images hide caption

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According to legend, the Explorers Club — a society of scientific adventurers — served its members a prehistoric dish at its annual dinner in 1951. By some accounts, the mystery meat was woolly mammoth; by others, extinct giant sloth. Now DNA analysis has provided a definitive answer — and unraveled a decades-long deception. Katherine Du/NPR hide caption

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When so-called senescent cells were removed from mice, they were healthier and lived longer than mice that still had the cells. Philippe Merle/AFP/Getty Images hide caption

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This San Francisco home collapsed in the 1989 Loma Prieta earthquake, which also claimed dozens of lives. ADAM TEITELBAUM/AFP/Getty Images hide caption

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Alchemist Hennig Brand looks focused, if maybe a bit drained, in this 1795 painting by Joseph Wright. The painting depicts Brand's discovery of the chemical element phosphorus. Joseph Wright of Derby/Wikimedia hide caption

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A view from Earth of a slender crescent moon in close proximity to the two brightest planets in the sky, Venus and Jupiter. Justin Lane/epa/Corbis hide caption

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The dark red color and looming posture of this Octopus tetricus likely signals menace to another octopus nearby, say scientists who studied 186 octopus interactions in 52 hours of underwater video. David Scheel/Current Biology hide caption

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New York City called a travel ban on vehicles in Times Square and elsewhere during last weekend's storm, which broke snowfall records all along the Mid-Atlantic coast. Yana Paskova/Getty Images hide caption

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The Aedes aegypti mosquito is one of two types thought to be capable of carrying and transmitting the Zika virus. Nelson Almeida/AFP/Getty Images hide caption

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