Originally Posted by
Ayetooey
If the majority of Sorbs/Serbs moved south in the 5th century, who's to say they didn't bring I-PH908 with them and create a founder effect in the Balkans? I-PH908 is equally non existent in the Belorussian triangle where it supposedly originates, it's something like 1%, with the rest of I2a being clades under Din-North.
The remaining Sorbs could easily of mixed with the R1a majority Slavs that surrounded them. Issue here is you're assuming the Sorbs of 2019 are identical to the Sorbs over 1500 years ago, and there's no evidence for this. Sorbs started speaking German by the 17th century, and most stopped speaking slavic by the 19th, but they're somehow representative of Proto Serbs 1500 years ago? Not to mention the centuries they spent under Polish rule, Bohemia, the mixing they undertook with Czechs.
I don't believe I-PH908 is "proto Serb" like Pribislav does, but this is a dishonest argument until we find White Serb samples from 500AD.