Whales’ Lower-Pitch Sound Has Experts Guessing
The song of the blue whale, one of the eeriest sounds in the ocean, has mysteriously grown deeper.
The calls have been steadily dropping in frequency for seven populations of blue whales around the world over the past 40 years, say researchers at the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration and WhaleAcoustics, a private research company. The scientists analyzed data collected with hydrophones and other tools and found that the songs, which they believe are by males advertising for mates, had lowered by as much as 30 percent in certain populations. Much of the song lies at frequencies too low to be detected by the human ear. […]
Scientists believe that only male blue whales sing. Female blue whales choose their mates based on size, a selection process that has fostered the species’ gargantuan proportions. And deeper might signal bigger. […]