Humpback mating songs are singular in nature, with only one song dominating all populations at any given time. Inevitably, however, the songs change. The study shows that the new songs almost always start with populations in Australia and then travel eastwards until they reach French Polynesia. This is believed to be a result of populations being higher in western regions than in the east. By the end of a breeding season, the new song dominates and eventually the old one dies out.
Scientists theorize that the learning process involves either males moving from one population to another, carrying the song with them, or by two migrating groups coming close together and sharing the song. The songs themselves tend to use elements of the original version in the new one, though completely different tunes pop up as well.
This is evidence of a cultural transmission that has been seen in no other species before, aside from human beings. No one knows quite why it happens, but the running theory is that males make up new songs to impress mates and that other males adopt it in order to not get left behind. I guess even whale ladies love a crooner.
Here’s one whale song, and although it’s not the latest hit, it’s still an oldie and a goodie: