Vowel gradation

[Ketsuban]

Are there any examples in attested languages of something like the Indo-European ablaut, where a wide range of roots contain a specific vowel which alternates in a systematic way to convey morphological information? I'm trying to learn more about what such languages do with roots that don't contain the alternant vowel as part of a conlanging thing, but everyone wants to use Indo-European (where we have no attested languages in which it's not degraded and generally unproductive) as their one and only example and things like the hollow verbs in Akkadian or Dinka having the same kind of vowel gradation to form plural nouns as English I-mutation are too different to be applicable.

[bradrn]

Are there any examples in attested languages of something like the Indo-European ablaut, where a wide range of roots contain a specific vowel which alternates in a systematic way to convey morphological information? I'm trying to learn more about what such languages do with roots that don't contain the alternant vowel as part of a conlanging thing, but everyone wants to use Indo-European (where we have no attested languages in which it's not degraded and generally unproductive) as their one and only example and things like the hollow verbs in Akkadian or Dinka having the same kind of vowel gradation to form plural nouns as English I-mutation are too different to be applicable.

I was going to suggest Dinka… what’s wrong with it? In fact just two days ago I linked a dissertation on vowel gradation which takes Germanic and Nilotic as its two reference points.

[Ketsuban]

The problem is that, like Germanic I-mutation, it's non-arbitrary - we know why the plural of mouse is mice, and it seems likely that Dinka plurals are similar in origin - and I'm working within a vowel harmony system which constrains the kind of vowel alternations I can achieve with that kind of mechanism. As a result something like Indo-European ablaut which doesn't seem to be the result of that kind of mechanism is preferable, but Indo-European ablaut as a functioning system is unattested so I wondered if there were other examples.

[bradrn]

The problem is that, like Germanic I-mutation, it's non-arbitrary - we know why the plural of mouse is mice, and it seems likely that Dinka plurals are similar in origin

Well, I mean… from a historical perspective it’s all ‘non-arbitrary’, right? Vowel gradation doesn’t just pop up out of nowhere…

I'm working within a vowel harmony system which constrains the kind of vowel alternations I can achieve with that kind of mechanism.

I’m not sure there are any attested cases of vowel gradation in a system which also has vowel harmony. The dissertation I previously linked suggests an information-theoretic explanation: vowel harmony is what you get when the root vowel and suffix vowel are roughly equally informative, whereas vowel gradation is what you get when the suffix vowel is far more informative than the root vowel. I suspect the closest you’re going to get is regressive vowel harmony, where the suffix triggers harmony in the root. (Or conversely progressive vowel harmony from a prefix.)

As a result something like Indo-European ablaut which doesn't seem to be the result of that kind of mechanism is preferable, but Indo-European ablaut as a functioning system is unattested so I wondered if there were other examples.

Why do you think it’s the result of a different mechanism? Admittedly I’m not an IE-ist, but it doesn’t look all that intrinsically different to me from the Germanic or Dinka situation.

[bradrn]

A knowledgeable friend sent me this paper on vowel length alternations in Cushitic: https://www.aai.uni-hamburg.de/afrika/p ... volume.pdf. Regarding this thread he suggests that a distinction in vowel length or stress could further turn into a vowel quality distinction. (Of course, there are numerous other ways to get vowel length or stress grades.)