Photo: flickker (Flickr)
Did you know that blue whales sing their songs exactly on pitch, with unbelievable accuracy?
Scientists at San Francisco State University analyzed over 4,000 blue whale songs off the coast of California. They found that all the whales produced a certain call type at exactly the same pitch — 16.02 Hertz. That’s about four octaves below middle C.
Even more remarkable than the fact that all the whales sing certain notes at the same pitch, is how perfectly on pitch they always are. From note to note the whales only vary in pitch by half a percent difference. By comparison, the difference between C and C-sharp is six percent.
Keeping The Pitch
That is nearly ten times greater than the difference observed in the whales. Pretty amazing, right? But, why are they such pitch perfectionists?
Well, one hypothesis has to do with the Doppler shift (the acoustic effect that makes the pitch of an ambulance siren sound as though it’s higher as the ambulance approaches and lower after it passes you).
Since the whale’s pitch is so accurate, they hypothesize that other whales may be able to locate an individual by listening for a slight shift in pitch that would be caused by the Doppler effect as the two whales move towards or away from each other.