While listening to our budgie, Tucker, declaim last night, I realized that although he parrots English, he doesn’t say any words with “th.”
Do similarly verbal species, like African grays, have a catalogue of phonemes that they can and can’t (or do and don’t) say?
BTW, I watched a cute video on YouTube of a budgie from Japan. It’s immediately clear that he’s parroting Japanese, not English, just from the sounds. You could probably tell me why.
Off the top of my head, I can’t think of any reason that a “verbal” bird would be unable to produce any sound. My recollection from grad school is that their mechanism of “talking” works very much like that of a speaker, so within the limits of engineering, I can’t think of any limits. Two questions come to mind for me:
1. Perception on the part of the parrot: to reproduce something, they presumably need to be able to hear it, which moves the area of discussion from the presence or absence of productive capabilities to the question of the presence or absence of perceptual abilities. Especially relevant in that th-sounds are of pretty low amplitude, so they fall into the category of sounds that you might be unlikely to be able to perceive, if you indeed had limits on perception, be they related to the anatomy of your ears or to what your brain does to process sounds.
2. Perception on the part of the human: it is within the realm of possibility that the bird is making the sound in question, but that the humans in the room aren’t hearing it.
Finally: here is a delightful paper on mynahs. More specifically: on one mynah, which points you toward my skepticism about the general state of research on verbal birds.