Sometimes you run into a language that has undergone a sound shift that is completely transparent, but at the same time phonetically completely absurd.
One such a sound shift is the shift of Proto-Berber *əβ > Northern Berber *i. Tashelhiyt and Middle Atlas Berber underwent *əβ > *u.
More peripheral berber languages have retained the phoneme *β like Augila and Ghadamès. The Touareg languages generally retain it as h.
Both these shifts are clear, as an example I'll use the word for 'milk'.
PB *aγəβ Augila aγəβ, aγf; Ahaggar ăx; Kabyle iγi; Riffian aγi; Middle-Atlas aγu; Tashelhiyt aγu; Ouargla aγi
This word is somewhat strange in Ahaggar (a Touareg language) as it did not retain the *β as h or even the second syllable at all. One can imagine that *ăxh yielded *ăxx to eventually get shortened to ăx though , but it's not exactly regular.
But as you can see, the small selection of Northern-Berber language clearly shows a perfect proof for the shift *əβ > *i. And citing more examples would simply give more convincing proof for this shit. But now the question is, how on earth does this work?
*β has a labial element so the Middle-Atlas and Tashelhiyt reflexes can be understood as coloring of the schwa to *ŭ and then getting lengthened to *u by compensatory lengething when *β was lost.
Such an explanation of colored vowels can not be used for Northern-Berber though. PB *u is simply reflected as *u in all of them so *əβ did not go through an *u stage before undergoing unrounding to *i. So what if the Proto-Berber sound we *h as found in Touareg rather than *β. We'd get *əh loss of *h could yield compensatory lengthening to *ə̄. As *ə is the high vowel in the short-vowel system, it could be assigned to either of the two high-vowels in the long vowel system.
While the above explanation makes the reflex of Northern-Berber understandable, we've only shifted the problem. Now we are stuck with a shift in Aujila and Ghadamès of *h > β. There's very possiblities to explain such a shift without any conditioning because of rounded/labial vowels in the vincinity.
So there we have it, not a sound correspondence that makes us rethink our theory, but definitely a sound correspondence which is extremely hard to explain phonetically.
I don't know anything about historic Berber linguistics, so I don't have any idea whether the developments I can think of are structurally possible, but maybe it helps:
1) *əβ > /əu/ > /u:/ > /y:/ >/i:/ > /i/< i.e. going via a long vowel which is fronted while the corresponding short /u/ isn't. Would fit especially if short/long vowel contrasts that subsequently collapse are a part of historical Northern Berber phonology.
2) *əβ > /əu/ > /iu/ > /y/ > /i/. That would parallel developments in Western Germanic languages, where /eu/, /iu/ became /y:/ or /i:/ while /u/, /u:/ were not fronted (or where fronting was a later development, as in Dutch).
Posted by: Hans | 02/11/2011 at 01:08 PM
Hey, I appreciate the suggestions. It can be of help to not know anything about the subject to give insights that aren't obvious to people deep in the matter
The first development is problematic as /u:/ would collide with Proto-Berber *u which doesn't front.
The second option may be possible but *əβ > /əu/ would probably clash with Proto-Berber *əw which reflects as /u/ in (almost?) all Berber languages.
Posted by: PhoeniX | 02/11/2011 at 08:10 PM
How about /əβ/ > /ə:β/ > /i:β/ > /i:/?
Posted by: Glen Gordon | 02/14/2011 at 07:17 AM
We know *ə < **i and **u, so maybe all of these are cases of **i - any evidence against that?
Posted by: Lameen | 02/14/2011 at 05:42 PM
Well, the evidence for *ĭ and *ŭ (Lameen's **i and **u) is extremely slim. So a lack of evidence against it would not be extremely convincing.
Evidence against it would be Labio-Velars in Kabyle followed by a *i < *əβ. Kossmann gives the shift *i < *əβ for Kabyle as uncertain, so there are probably very little examples of this. But I'll have a look.
Posted by: PhoeniX | 02/15/2011 at 06:39 PM