One single vocalic phoneme in PIE?

[Juan Alberto Alonso]

Dear IEists,

I'm new in the list, so the point I wanted to raise might have been
discussed already (in that case I apologize for coming back to the issue).

As far as I have read in the specialized literature, some reconstructions
assume a single vocalic phoneme */e/ for the early stages of
(pre-inflectional) Proto-Indoeuropean, probably with two alophones [e] and
[o] that would later become phonemes of their own and the
origin of the (e/o/0) ablaut phenomenon (cf. Gr /steixo:/, /stoixos/,
/'estixon/).

The point is of course that such a reduced vocalic inventory is quite
unusual throughout the world's languages. The only example I know of
are some languages of the Abkhaz-Adygean family, (e.g. Kabardian), spoken in
the Caucasus, with only two vowels. By the way, these
languages are ergative and they have a big number of consonantal phonemes
(up to 80 in Ubykh).

Juan A. Alonso

[ Moderator's note:
  I have already directed Mr. Alonso to the archives for the recent discussion
  of languages with putative small inventories of vowels.
  --rma ]