> What distinguishes PPIE from PIE is the introduction of the
> Ablautvokal.
==============
PIE didn't need to introduce ablautvokal
It's clearly a proto-Sapiens phenomenon :
with -o- for nouns and -a- for verbs.
This clearly surfaces in Chinese.
The innovation of Central PIE
was the use of e / o to express tenses.
It remains to be proved that this innovation
can be documented in Anatolian and Italo-celtic.
Arnaud
=========
> PPIE had /a/, /e/, and /o/.
===========
There is no phonological contrast
between /a/ et /e/
neither in PIE nor PAA.
Arnaud
================
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