This map is only partially true. For exaple, the eldest MRCA I2a1 M26 are living in southern France, not in Italy.
Illyrians didn't bear I2a1 Din , that's for sure. Take a look on Nordtved's graphs and you'll understand why.
Illyrians were a mixture of J2, E1b-v13, R1b and G2a. A typical pre-Slavic Balkan mixture.
I think not much G2a, instead they had some pre-Illyrian R1a from Pelasgians....
research shows that R1a is ancient old in the area.... we can assume that several waves of R1a did contribute to observed extreme diversity, but still the diversity much larger than elsewhere is likely to point out on ancient old settlement of R1a in Balkans... I think this is related to Pelasgians... that conclusion I had already introduced around 1 year ago on this forum, after comparing spread of R1a in Greece with data about Pelasgian settlements....
south Slavs have single common denominator - I2a-din.... R1a is in Albanians of FYRM significantly higher than in areas like Montenegro, and on roughly same level as in Serbia and FYRM Macedonians
again R1a in Greek Macedonia is much larger.....
only conclusion is that much of R1a was already on Balkan when south Slavic people arrived, while most of I2a-Din was not already there...
in my opinion Pelasgians and Thracians were originally dominantly R1a... i think that before arrival of E-V13 and J2 whole east Europe was R1a area... but that does not mean they were culturally same as proto-Slavic because this was much before Slavic language, and probably in times of proto-PIE language....
i think R1a was spread with Kurgan culture....
although it is ogood theory, I am not sure that PIE language was in fact spread by Kurgan culture...
concerning I2a-Din, pattern of I2a-Din spread along the Danube from Bohemia to Black sea and around it seems clear... the presence of haplogroup I in Asia (in Kurds, Sarbans, Sart, white Sart) seems to match the supposed movement of PIE speakers
around 1800 BC indo-Europeans reached India in a movement starting from Kurdish area...
around 1200 BC "sea peoples" bring down most middle east empires and threaten Egypt... their key stronghold can only be Kurdish area...one of them are called Sherdana and leave place name Serbonian bog in Egypt...
it is haplogroup I that spreads from Bohemia down the Danube around Black sea and deep into Asia....
Aryans = Serians?
no, there is no haplogroup I in India.... Indo-Arian settlements match J2....
perhaps originally Aryans = Syrians = Sumerians = J2...
Strabo says that both tribes of Cappadocians are white Syrians different from other Syrians by brighter skin, and he says that Syrian = Sumerian
note that Serica in north west China is reach in both J2 and I
perhaps Sumer was originally J2 (pay attention to elevated spread of J2 in area of Sumer)..those people later spread to north and part of them (white Syrians) has at some point incorporated some I2a people who were originating from Europe area around Black sea, area with milder climate, and had hence brighter skin...thus, J2 with some I2a gave white Syrians...
perhaps Sumerian empire could be responsible for spread of J2 and I2a further to east... to area where much later Pomponius Mella finds Serres between Scythians and Indians...
Cappadocia is J2 hotspot...
same as Syria
J2 is origin of names Syrian and white Syrian and Aryan....
I2a in Asia had tribal names such as Sherdana, Sarbans, Sart, Scordisci, Kurds ....
I2a in Asia came from Europe via Black sea
I2a in Balkans came from central Europe...question is with Serbs and Croats or before?
both... early ones with Scordisci and later one with Serbs.. unless those are same people...
Sumer was on other hand not PIE speaking, so the PIE language came from I2a people

hence the weird saying of Serbs "speak Serbian so that the whole world understands you"
imposing the language could have come only through superior military or culture... i place bets on military...it is around 2150BC that Gutians come down from Zagros mountains (where Kurds live) and take over Sumer and rule over it for 100 years... later Akkadians and than Elamites took over.... but Cappadokians (and perhaps some more east colonies) could have stayed under control of Gutians...giving white Syrians....and spreading PIE language in area of Serres - that stretched between Scythians and Indians.....PIE language reached Indians in 1800 BC
peoples name white Sart is perhaps not the same in origin as white Syrian
white Syrian meant whiter Syrians, while white Sart meant west Sart, same as white Serbs meant west Serbs......
http://en.wikipedia.org/wiki/Gutian_dynasty_of_Sumer
so could PIE people be Gutians and could this tribal name be same as Goths?
"letopis popa Dukljanina" (chronicle of priest Dukljanin" claims that south Slavs are just Goths...
in fact we know that Odoacer leader of Goths was half-Scirian and I have explained possible link Scirii- proto-Serbs, as Scirii are found in locations where we find I2a-Din south (near Baltic and in Bohemia/Bavaria)....Scirii/Hirri being paired in same way as Srbi/Hrvati.... Heruli (same as earlier Hirri in my opinion) disappearing from history on place where imediatelly after state of Hrvati appear...
origin of I2-din could geographically and genetically fit nicely in originally east germanic branch of people... but its just an idea... main dialect of Kurds is Sorani, part of it bares name Garmiani... to me that is same as Germani...