Nubian(however credit to you for favouring the out of africa/eve hypothesis on genetic markers in mtDNA (though didnt specifically reference it)) is so ill informed as is sop'.
They are utilizing evidence and conjecture and mere fantasy from contradicting sources to prove a self styled point of self promotion.
The truth is that India has been invaded numerous times due to the prevading politico-religious view of the day. Various political struggles occur within large nations leaving them vulnerable to attack/invasion as we see today with the USA and recently Spain.
Is it a stretch to assume this happened in ancient India? Anyways, the political vacuums, military vacuums left behind could have aided in invasions, perhaps political foes thought of enlisting the help of foreigners to usurp power is a possibility-think back to Alexander of Macedon (however he was sent home with a beating from King Porus of Punjab)-yet historians always write that Alexander's men rebelled, were homesick or they actually did successfully invade India. The truth is in aligning ancient scriptures (Vedas,etc) and hard core archeology-note as we dig deeper in to the underlying strata we find more evidence-people of Wheeler's and Mueller's time stopped excavations and exclaimed India was invaded by horse men since we found no horse remains, or evidence thereof. Funny since modern archeology has uncovered hrose remains dating to at least 4000BCE and horse paraphernalia as well. Let's not forget about basic linguistics either, that support the connection of Dravidic and Sanskritic languages, as being given a similar root-protoIndic-
Anyways, have fun, but remember that truth is the ultimate knowledge! (Funny how the treasure of Atlantis is really knowledge and it seems off the coast of Gujurat may lie 'Atlantis') but then again how can this be? Not India, damn why cant it be Europe or close to Europe..yeah that's it lets make civilization's cradle in the middle east (that way it is still close to Europe)LOL!