The reason why whales sing has puzzled scientists and casual observers for decades. Many explanations have been offered for the vocalizations of whales, but despite many comprehensive studies, no explanation has proved conclusive. Whether a mating call, an advanced echolocation technique, or a means of communication, whale song remains a continual mystery of the giant marine mammals, and inspires debate among scientists worldwide.
Although toothed whales produce vocalizations, whale song is generally used to refer to the sounds of baleen whales, particularly the blue and humpback species. Whales do not possess vocal cords, and their exact mechanism for singing is unknown. It is known that they do not need to exhale to produce sound, leading researchers to postulate that they can somehow recycle air in their bodies. The whale song consists of patterns of moans, whistles and clicking sounds divided into repeatable sections scientists call “phrases.” The typical song will last up to thirty minutes.
Breeding behavior and mate attraction have long been suspected as reasons why whales sing. Only males engage in singing, and each male sings the same song. However, studies have never proved conclusive, as there is little evidence that links breeding to singing. One of the difficulties in researching this theory is that whale song sounds can travel extremely long distances under the ocean. This range means that while there may be no female whales in the singer’s vicinity, it is possible that breeding females far away could hear the song.
Another recent explanation for why whales sing is that they are using echolocation to give information on their surroundings. Eduardo Mercado III, a New York scientist, has suggested that whales may be able to pinpoint locations by listening to the sound distortion present in incoming waves. Mercado also suggests that only males sing because they may actively search out other whales for mating, while females may wait to be found. This theory is not supported by direct evidence, but is gaining some support in the whale researching community.
One of the most extraordinary features of whale song is that all male whales in a pod will sing the same song, but the song changes from season to season. Some multiyear studies show that while phrases of sound are repeated, no songs from any two years are identical. This has lead to theories suggesting that one reason why whales sing is to differentiate between pods. Another popular theory is that whales sing as a way of passing on a cultural meme or community history from year to year. These theories concern some people, as it suggests an intelligence not generally considered possible in any species other than humans.
The simple answer to why whales sing does not yet exist. Most scientists agree that a key to discovering why whales sing is ensuring that they have protected populations, so conserving whales may be the first step to solving the mystery. The possibility of whale song as communication is frequently raised as a factor in activist attempts to permanently ban whaling worldwide. Until direct evidence is produced in support of a particular theory, most scientific theories are considered equally possible.