Raakhee Venugopal’s answer
I would like to think that this difference (if it does exist) is because of the higher concentration of Dravidians in south India and of Aryans in north India. But then again, Dravidians and Aryans are not mutually exclusive either. There has been a lot of inter-mingling of races leading to the formation of many mixed races, with mixed facial features.
Jitendu Sarkar has written an excellent article on this subject where he chronicles this elaborately. His article can be found here –>
Not all south Indians have rounded noses…
…and not all north Indians have hooked noses either!
(Pictures for illustrative purposes only)
Hope this answers your query.