Beluga whales can vocalize in a way remarkably close to human speech – or at least one of them can, according to new observations described in the journal Current Biology. The discovery came as a shocker to scientists, who previously knew that dolphins sometimes mimic the patterns and durations of human speech but had no evidence that an animal may spontaneously put its vocal skills to such a mimicry test.
NOC’s vocal bursts averaged about three per second, with pauses interspersed similar to human speech. The frequencies within those bursts resembled human “harmonics” rather than whales’ normal vocalization patterns.They went on to teach NOC to make the speech-like sounds on command and fitted him with a pressure transducer in his nasal cavity to investigate the way the whale was pulling off the unique vocalizations. It turned out the sounds were due to a rapid change in pressure within his nasal cavity, which he amplified by over-inflating a sac in his blowhole that is normally used to stop water from entering the lungs.