Photo: Wikipedia , CC/GFDL Frequency of Tones Shifted Down Scientists from the Scripps Institution of Oceanography at UC San Diego have noticed something very interesting while studying the songs of blue whales: “The basic style of singing is the same, the tones are there, but the animal is shifting the frequency down over time. The more recent it is, the

lower the frequency the animal is singing in, and we have found that in every song we have data for,” said Hildebrand, a professor of oceanography in the… Read the full story on TreeHugger

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Pitch of Blue Whale Songs Is Declining Around the World, But This Could be a Good Thing