A large portion of the population in south indian states don't have surnames. I think I'm the first person in my family line in what must be centuries that has the same second name as my father (so what you would consider a "surname") because I was born in the US where there is a cultural expectation to have a "family name." So my grandfather's first name, which was my fathers second name, is now my "surname." Otherwise, my fathers first name would have been my "last name," as is the case with my cousins that were born in India.