Civilization started in West Asia and NOT in the Steppes.
That is complete old fashion theory. Southeastern Europe culture of Varna and Cucuteni Triploje were more advanced that their mesopotamian counterpart (before the Uruk period). Vinca culture even invented writting before Sumer but unfortunately we can currently not decipher it.
The proto Kurgan people of Sredny stog had their copper from Southeastern Europe, not the Caucasus.
In fact all the Western branch of IE had direct contact withe late cucuteni Trypolje culture while the contact with Transcaucasia and Mesopotamia were indirect and distant.
Maykop culture influenced Yamna culture, and Maykop culture was in turn influenced by Kura–Araxes culture. Kura–Araxes culture was influenced by North-Mesopotamian cultures.
Where do you think maykop people had their Kurgan and their horses from??
Kurgan were first erected in the Steppe since Sredny Stog II that is to say before Maykop culture. Maykop culture is an ofshoot of the Steppe Kurgan culture over a Caucasian population that must have spoke a Caucasian language like today.
late Cucuteni Trypolje culture had far more effect on yamnaya people than maykop. Read david Anthony
The Horse, the Wheel and the language. there is a chapter about the origin of Western ie language in which he never mentions the Maykop culture. The western IE languages originated in Yamnaya and its ofshoot, Usatovo (southern Ukraine) in particular.
And as I already said, Maykop culture is not even considered the ancestor of the Anatolian branch of the IE languages. It is an extinct branch of the eraly IE expansion. If Maykop culture really was the origin of any modern IE language, we should see Caucasian loanwords or cognates like we see with Uralic language family.
and Maykop culture was in turn influenced by Kura–Araxes culture.
Kura Araxes stared after Maykop and it was even less kurganized than Maykop. The IE never managed to impose their language over the local folks that's why Indo European has never been spoken in the area.
"In the Armenian hypothesis of Indo-European origins, this culture (and perhaps that of the Maykop culture) is identified with the speakers of the Anatolian languages."
Why didn't you quote the first part of theis wikipedia article? the languages of Maykop and Kuro Arax were more like:
Ethno-Linguistic Makeup
Hurrian and
Urartian elements are quite probable, as are
Northeast Caucasian ones. Some authors subsume Hurrians and Urartians under Northeast Caucasian as well as part of the
Alarodian theory [23]. The presence of
Kartvelian languages was also highly probable. Influences of
Semitic languages and
Indo-European languages are also highly possible, though the presence of the languages on the lands of the Kura-Araxes culture is more controversial.
Writing exists not so long time and it was invented in West Asia.
It was probably invented earlier in Vinca culture, Southeastern Europe.
What I'm trying to say that mayor Indo-European (and Hurrian and Semitic civilizations) in West Asia exterminated all other small native Indo-European languages.
OK and by accident they only kept the non Indo European languages alive.
West Asia was homeland of many extinct Anatolian Indo-Euroepan languages.
Not according to most scholars who favour a Balkanic hypothesis or west steppic : Suvorovo, Cernavoda...