What is an alien phonology?
An alien phonology is a system of sounds — and perhaps other, non-vocal signals — for a language designed to be used by beings that are not human. It is designed to take advantage of a non-human anatomy, and will often use mechanisms of sound/signal production that would be convenient for the beings the language is made for, but are either inconvenient or impossible for humans.
What might an alien phonology have in it
An alien phonology could contain any phoneme (sound that is seen as being different from the other sounds) that would be easy for the alien to use. It's not too hard to imagine one, without even leaving Earth.
- Plates that make noise when they glide over one another.
- Used by many insects, chirp chirp!
- Colour changes.
- Many octopuses can change colour fast enough to use colour phonemically (to distinguish words form one another).
- No vocal cords.
- Birds have no vocal cords. Instead, they have a different kind of vocal organ called a syrinx.
- Two air streams
- Some kinds of birds use two air streams when they sing. (Mentioned here.)
- Non-aerial sound transmission
- There is evidence that pachyderms can send and receive sounds through the ground.
- This could be useful for a place where there is little air.
- Flashing lights
- Some species of deep water fish communicate warning signals with pockets of bio-luminescent bacteria that they can cover and reveal alternately.
Any and all methods of noise production and such can be used as phonemic signals, just because red is not phonemic to humans does not mean it isn't for octopi. Just because the smell of sulfur doesn't make an English word an adverb, doesn't mean it can't for an alien.
Alien language should be built around alien anatomy. We recommend you figure out how they look; how would they make their sounds? What would be the most effective method of communication in their environment; would sound be used at all?
Throw away traditional thinking when you work with aliens, they are after all, alien. When you're working with aliens, anything goes.
If your aliens do make sounds using their breathing apparatus — a common supposition although, as noted above, not at all necessary — you may find it useful to consider in detail how their vocal tract works. That is, consider the shapes of the cavities that air passes through on its way in and out, and thus the internal spaces that may provide resonance for both vowels and consonants, and places of articulation for consonants.
In humans, sound comes from the larynx — the voice box — and passes through the laryngeal cavity, the pharynx, and the oral and/or nasal cavity. Here's a diagram (right) naming parts of the human vocal tract.
Simple changes to this human pattern can lead directly to variations in sound inventory. For example, in the Chanur novels of C.J. Cherryh, a rat-like intelligent species called the kif has a second set of teeth, well down in the gullet, used for pulping food after it's first been chewed by the outer teeth — so they would have a second sort of dental place of articulation, and their language has a lot of different kinds of plosives (or, perhaps, clicks).
Birds have a different set of internal spaces for sound production, starting with a syrinx instead of a larynx. (The ancient Greek word syrinx means panpipes.) Birds would not have a labial place of articulation, of course, as they don't have lips; the Latinate adjective for the beak as a place of articulation would be beccal.
Another straightforward variation on the vocal tract would be something like an elephant's trunk. Which is not, technically, nasal; the Latinate adjective for of-or-related-to-the-trunk would be manual (as, mentioned way back in the Beginner level of this book, trunk of an elephant is one of the many meanings of the Latin noun manus).