Somali refugees lead their herds of goats home for the night outside Dadaab, Kenya. A new study shows that animals in many parts of the developing world require more food — and generate more greenhouse emissions — than animals in wealthy countries.
World War Z is just the latest pop-culture incarnation of the Zombie Apocalypse. Adam Frank says the zombies keep coming because they're trying to tell us something.
Crew members unload a catch of sockeye salmon at Craig, Alaska, in 2005. Researchers say fish are being found in new areas because of changing ocean temperatures.
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