Hereditary, regional factors and skin tone

In a country like India, where historically the Aryan invaders gradually drove the original Dravidian settlers to the south of the country, citizens have different shades of skin, complexion, depending on their genetic makeup.

For example Punjab which has been invaded by a large number of foreign armies starting from greek invader Alexander the Great, Persians, Mughals and many of men and women have the facial features, height and complexion of the greek and foreign invaders . This explains why many of the top bollywood actors who are fair and handsome are mainly from Punjab like the Kapoors, Khannas,

On the other hand many south indians like Tamilians are dark complexioned compared to other indian citizens, residing or originating from other parts of India.