By Susan Milius
Biologists report new progress in translating the sophisticated communication system of black-capped chickadees.
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When the little birds spot a lurking predator, they burst out with variations on their “chickadee” calls. Tests with 15 predator species show that birds vary those calls depending on how dangerous the predator is, says Christopher N. Templeton of the University of Washington in Seattle. For example, the greater the danger, the more dee syllables the birds tend to add at the end of “chicka.” Recordings of these varied alarm calls inspired appropriately mild or intense responses in a chickadee flock, the researchers report in the June 24 Science.