Cosmos ,Sanatan Dharma.Ancient Hinduism science.
Aryan theory was created to divide India So British could keep ruling India . But what happened that after freedom , unfortunately Nehru Gandhian rule did not change wrong history , in fact created more controversy and tried to finish real history of India but with Internet age , truth is coming and this was a major truth when in a historian conference in USA, Aryan invasion Theory was debunked finally . Still many stupid Indians still keep their stupid brain in British jail so to keep India divide between North and south.
From a non-native eye, the two averages kind of looks the same. Most wouldn’t be able to distinguish that they were from different areas. Racially there is nearly no difference in the current population since the Aryan-Dravidian split and the Aryan invasion theories have been proven to be myths by several studies, showing there is no north-south divide.
The first African migration into India occurred around 60,000 years ago (the later ASI), the African migration which moved into Europe (ie. Eurasians) later migrated in waves from 40,000-12,000 years ago (ANI).
An interesting factoid (which should be obvious):
Larger Genetic Differences Within Africans Than Between Africans and Eurasians
Every modern Indian person is the descendant of a mixture of two very ancient populations, known as the ANI (Ancestral North Indian) and the ASI (Ancestral South Indian). The mixture can range from 70-30 ANI-ASI (Kashmiri Pandits) to 40-60 ASI-ANI (the dalit community Malas from Andhra). The admixture dates all occurred between (2200BC to 100 AD) with South Indian groups showing earlier mixture dates. In short there were no “pure populations” of ANI or ASI from about 1900 years ago.
This mixture in the period between 4,200 to 1,900 also shows that there is no evidence that there was substantial migration from West Eurasia into India during this time (since the population of India was so big that it is impossible for a West Eurasian source large enough to contribute to the resulting mixture), debunking the Aryan Invasion theory.
In conclusion, racially both the populations have common origins, visually they would be very difficult to tell apart (from a foreign perspective). However culturally and linguistically there is a world of difference (Any two S.Indian state themselves would easily have more cultural/linguistic differences than say any two European countries), these differences are what make India such a special and amazing place.