Science published a fascinating study in April 2013 suggesting that cultural transmission is responsible for the prevalence of “lobtail feeding” behavior in a group of humpback whales found in the Gulf of Maine.
First observed in 1980, lobtail feeding involves a variation of bubble feeding. In bubble feeding, whales blow bubbles around fish to get them to clump closer together, and then lunges upward through the densely-packed fish.
With lobtail feeding, the humpback whale first slaps his tail on the surface of the water several times before diving underneath the water and engaging in bubble feeding. One hypothesis is that the tail slaps discourage the fish from jumping out of the water.
Researchers Jenny Allen, Mason Weinrich, Will Hoppitt, and Luke Rendell examined different models to explain the spread of the lobtail feeding to 287 of 700 observed humpbacks in the Gulf of Maine since its initial observation in 1980:
We used network-based diffusion analysis to reveal the cultural spread of a naturally occurring foraging innovation, lobtail feeding, through a population of humpback whales (Megaptera novaeangliae) over a period of 27 years. Support for models with a social transmission component was 6 to 23 orders of magnitude greater than for models without. The spatial and temporal distribution of sand lance, a prey species, was also important in predicting the rate of acquisition. Our results, coupled with existing knowledge about song traditions, show that this species can maintain multiple independently evolving traditions in its populations. These insights strengthen the case that cetaceans represent a peak in the evolution of nonhuman culture, independent of the primate lineage.