Thursday, April 21, 2011

New catchy tunes spread quickly through whale populations

Ok I have a confession to make and that is that I have a huge soft spot in my heart for characteristic megafauna. Whales were my first love and are probably the reason that I'm a biologist today.  So I can't resist this fascinating study that was recently published by Garland EC et al. in the latest issue of Current Biology 21:1-5.  The authors recorded songs of Humpback Whales throughout the South Pacific over a period of 11 years.  They found that within a population the whale songs tended to shift through time, but all the whales in a population sang the same song.  Every once in a while the "it" song was suddenly replaced with a completely new song.  When this happened the new song was rapidly transmitted throughout the population and then over time spread to other populations.  The songs traveled from West to East such that in 2004 French Polynesian whales were singing the song that East Australian whales had been singing back in 2002.  However by this time the East Australian whales had already moved on to a new song that wouldn't start to hit French Polynesia until 2005.  So it's as if the whales in the west are the hip trendsetters and the eastern whales are always rushing to catch up with the coolest new fad.  The most fascinating part of this story is that like shifting fashion trends or teenage colloquialisms the song is constantly changing but within a population there is conformity.  This is a fascinating example of cultural evolution occurring both within and between populations and suggests these whales have a complex social structure.