"Researchers solve mystery of why southern hemisphere whales switch suddenly but in north it is gradual"
"From Abba’s Mamma Mia stealing the crown from Queen’s Bohemian Rhapsody to Rihanna’s Diamonds knocking Psy’s Gangnam Style off the top of the charts – even the catchiest song eventually becomes superseded by a new number.
But the phenomenon is not unique to humans: male humpback whales also sing – and change their tunes.
Now researchers say they have unpicked the mystery of why humpback whales in the southern hemisphere suddenly switch their songs, while those in the northern hemisphere tend to change theirs more gradually.
The key, they suggest, is that different humpback whale populations in the northern hemisphere all come into contact with each other during the feeding season – and in the process males can exchange tweaks to their ditties. The upshot is that all the populations sing from the same song sheet, with the piece evolving slowly over time."
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