I have read somewhere that kings in South India tried to get associated with the dynasties of north or with Aryans in their later part of rule, though earlier south Indian rulers did not try the same,
I dont know how much truth it could be, anyway its just a theory of someone, and i do not have much information on this so can't comment much. During the studies of the Pallavas, they claimed their descent from Dronacharya who would come under the so called Aryan category, not sure about the Cholas If there is any truth in north-south India divide, I wonder if there is any dynasty in southern India which specifically attach to aboriginal southern tribe, above are just statements, no intention to hurt any emotion or feeling, if it does, I tender my apologies