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Wikipedia has a fabulous tree showing how human populations are all related on the Y chromosome. Trees based on just the Y chromosome might give better results than trees based on the entire genome because the latter is confounded by interbreeding between lineages. By contrast the Y chromosome is only passed on the male line and since men did not interbreed with each other, we get a clean separation of branches.

In addition, mutations on the Y chromosome tend to be neutral, so it serves as a more reliable molecular clock.

source: wikipedia

Moving from left to right, you get an interesting transition from Negroid to Caucasoid to Mongoloid phenotypes.

I suspect the Caucasoid race evolved in India. The first modern humans to leave Africa were almost certainly morphologically Negroid and were drawn to India because it resembled the African climate they were adapted to.

Then among the indigenous Indians, there was likely a split between the proto-Island Indians (ancestors of Andaman Islanders) who remained Negroid, and mainland Indians (who started evolving Caucasoid hair and beards),

The race known as Australoids may simply be Negroids evolving into Caucasoids

Some of the proto-Caucaoids stayed India where they remain as relic isolated tribes, others headed to Australia where they are known as Australian aboriginals, while others headed Northwest where they evolved into proto-Arabs and eventually whites,