The largest animals to have ever lived–blue whales–while feeding on the some of the smallest animals–krill–can swallow half a million calories in a single gulp. That’s around 1,000 pounds of food.
Recording this feat involved a researcher painstakingly following tagged blue whales, recording their feeding habits, and then exhaustively running simulations to determine their caloric intake. Interestingly, even the half a million number is conservative. Krill have been known to cluster in groups sometimes a thousand times larger than what the researcher simulated. Imagine those calories!
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