I think Christophe has it about right. It seems that lgs. that harmonize suffixes with stem vowels are showing progressive assim. There can thus be not only front-back harmony, but round-unround harmony (and both together) (Turkish?), while umlaut (as in German) is regressive (then sound change-- loss/change of the conditioning final vowel-- muddles thing up, like Engl. foot, feet or mouse, mice)

Prevli has progressive V-harmony, but only within the base word, not in suffixes. So a word like CoCaV > CoCV ~CoCV, or CaCiV > CaCeV ~CaCVe etc. CVCV forms work a little differently, and VV sequences even more different.....Without looking at the phonology page, I can't give any more details.....

Austronesian languages show some sporadic assimilations, almost always involving schwa. Penult schwa (which seems to have been inherently unstressable) frequently harmonizes with the ultima vowel (we're talking CVCV(C) forms here), or vice versa (ult. schwa harmonizes with the stressed penult V), producing lots of odd "doublets" in people's reconstructions.

On Thursday, March 27, 2014 4:45 AM, Christophe Grandsire-Koevoets <[log in to unmask]> wrote:
On 26 March 2014 22:49, Guilherme Santos <[log in to unmask]> wrote:

> Diachronically speaking, where does vowel harmony come from?

One word: *inertia*.
In a few more words: *principle of least effort*

> Is it like some sound change that is unpredictable and the language makes
> sense out of stuff by having the vowels harmonize, or is it just that the
> sound changes transform vowels into schwa-like things and they start
> borrowing the characteristics of the neighboring vowels?

Neither. As Siva and David wrote, it's assimilation at a distance due to
articulatory pressures: trying to communicate clearly while exerting the
least amount of effort possible. So forward assimilation occurs when
inertia keeps the tongue for the following vowels in about the same
position as the first vowel (leading to vowel harmony), while backwards
assimilation occurs when the speaker anticipates a certain vowel at the end
of the word and starts moving their tongue to the right position before
they even got there (leading eventually to umlauts and ablauts and all
other kinds of -lauts ;) ). Same with lip position, leading to assimilation
in rounding.
Christophe Grandsire-Koevoets
President of the Language Creation Society (

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