By: Reagan Smith
Source: Flickr @Steve Snodgrass
Whales communicate in a complex series of vocal noises that can travel thousands of miles across barren ocean water. Hooting and shouting, clicking and calling, they produce a unique cacophony of sounds in order to call out to potential mates, talk to their young, and search for relatives.
The three categories researchers have assigned to these noises are clicks, whistles, and pulsed calls. Clicks are, essentially, short sound waves that whales use as a form of echolocation meaning that they bounce them off objects in their surroundings in order to determine their shape and relative distance. Considering how dark the ocean water is 2,000 meters below the surface, having an alternate method to “see” the environment is key to survival. Whales also utilize clicks to communicate socially with others of their kind; they can even use them to differentiate between friend and foe! Whistles and pulsed calls are primarily used in social interactions.
Interestingly, it has been documented that different groups of whales each have their own “dialect.” To better understand this, let’s take a look at how whales form communities. Whales tend to travel in groups known as matriarchal-pods, which are organized around a central group of elder females. Most matriarchal-pods have been together for several generations, and, as a result, have a strong sense of community. Another result of this is that different pods have different “dialects,” meaning that each pod has a series of whistles and calls that are unique to them. Additionally, not only does each pod have a unique dialect, but it also seems that each member of a pod has their own name, which is expressed via whistles and/or clicks. and It’s almost like a nametag for the whale, and it enables other animals and researchers alike to identify the particular whale.
How do whales produce these sounds? Different species have developed different methods. Odontocetes are a type of whale with teeth, and include the sperm whale, killer whale, and beluga whale. These whales use a complex system of air sacs and soft tissues surrounding their nasal passages to produce short, high frequency clicks. As air passes through the nasal passages, it vibrates the tissues, which produces a sound wave that travels through their melon— an organ full of lipids that is located at the forefront of the whale. The melon concentrates and changes this wave to make it narrow or wide, based on the needs of the whale at the moment.
Odontocetes also utilize their larynx to generate low frequency sounds, giving them a wide range of vocal “tools” to utilize in order to communicate and survive.
Mysticetes—whales with a baleen in place of teeth—encompass other commonly-known species like the humpback whale and the blue whale. They do not use the air sac/tissue system found in odontocetes; instead, mysticetes have developed a modified form of the larynx through evolution. This organ contains a rigid u-shaped tissue similar to the vocal folds found in other mammal species. It is located adjacent to a pouch known as the laryngeal sac. Muscles contracting in the throat and chest create airflow from the lungs and sac, which pushes air across the u-fold. The u-fold then vibrates and produces sound.
With all that being said, whales can be quite creative in how they get their point across, even able to do so nonverbally. Many whales have been documented hitting the surface of the water they are in with their tails and fins, sending a soundwave pulsing through the water for hundreds of meters below. This process is known as fluke slapping, and can be used to signal a warning to others; it can also be used to scare fish into clustering together, thus forming an all-you-can-eat whale buffet. Additionally, tooth whales specifically perform jaw claps by shutting their jaw sharply to signal aggression.
Source: Flickr @Isaac Kohane
The research done on whale communication supports the hypothesis that whales are more alike humans than we initially thought. We are both a social species, with specialized forms of relaying information to one another. And although our two habitats couldn’t be more dissimilar, it’s not too absurd to believe that if humans were an ocean-faring species, our society would be quite similar to that of the whales.
Sources:
No changes were made, Beluga | I had never seen a beluga before. It is a beautiful… | Flickr, License: Creative Commons Legal Code
No changes were made, Whales | A Whale Called Eden | Isaac Kohane | Flickr, License:
What did you learn?
What is the distinction between odontocetes and mysticetes?
Odontocetes are toothed whales that use either their larynx or an air sac/blowhole system to produce noises. Mysticetes have baleen in place of teeth and use a modified larynx to produce any and all sounds.
What is the purpose of the clicks whales make? Are they similar to any technique used by another animal?
Whales use clicking to determine their surroundings and differentiate between prey and predator. The clicking acts as echolocation, because whales bounce the short soundwaves off objects and animals and receive the wave, analyzing it and reacting accordingly.
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