Humpback whales sing increasingly complex songs, but University of Queensland researchers have discovered they may suddenly switch to something simpler, in a ‘cultural revolution’.
The study examined the structure and complexity of songs sung by the eastern Australian humpback whale population over 13 consecutive years.
Dr Jenny Allen from UQ’s Cetacean Ecology and Acoustics Laboratory said members of humpback whale populations were known to sing the same song at any one time.
“Typically, these songs changed gradually, possibly through embellishments by individual singers,” Dr Allen said.
“We suspect the embellishments allow bulls to stand out from their peers, much like teenage boys trying to stand out from the crowd.
“But every few years the songs are replaced - always by something simpler - suggesting there is a limit to the whales’ capacity to learn new material.”
Dr Allen said humpback whales provided a good model for cultural learning in animals, as they learned and spread their songs quickly over entire populations and even ocean basins.
“This is cultural transmission on a scale comparable to what we find in people,” she said.
“By learning more about culture and social learning in animal species such as humpback whales, we can gain a better understanding of what led to its development, and what evolutionary value it holds.
“By answering these questions in animals, we might be able to clarify why cultural and social development has occurred to such a unique degree in humans.”
The study is published in Proceedings of the Royal Society B: Biological Sciences.