a) No one can be sure what language the Catacomb cultures spoke.
http://en.wikipedia.org/wiki/Catacomb_culture
M.Kelkar
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More recently, the Ukrainian archaeologist V. Kulbaka has argued that the
Late Yamna cultures of ca. 3200-2800 BC, esp. the Budzhak, Starosilsk, and
Novotitarovka groups, might represent the
Greek-Armenian-"Aryan"(=Indo-Iranian) ancestors (Graeco-Aryan,
Graeco-Armenian), and the Catacomb culture that of the "unified" (to ca.
2500 BC) and then "differentiated" Indo-Iranians. Grigoryev's (1998) version
of the Armenian hypothesis connects Catacomb culture with Indo-Aryans,
because catacomb burial ritual had roots in South-Western Turkmenistan from
the early 4th millennium (Parkhai cemetery)
It seems clear : South-Central PIE.
Arnaud
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