May be you are right if i live with them but you can differentiate easily south Asians and European's but differentiating you guys at first look for a stranger like me is quite difficult...
Hope one day I visit both China and Japan..
Last year I had a summer sabbatical in New Delhi. When i first arrived to India, first, i was taken by the heat of the country. The sights and sounds, and even the smell is rather different to my native Sapporo, Japan as well as my host country [USA]. The heat! It is so hot in India. I tell you , when i first arrived i never sweat so much in my life, lol.
My first perception of Indian people was that they all look thesame, there is a distinct South Asian phenotype. But as i developed friends there, and developed relationships with the local cafe shops, and restauranteurs, i began to discover there are so many different beauty phenotypes in India. For example, i had a very good friend named Therunathan, a fellow Ph.D. candidate who i met at the seminars. He's from Tamil Nadu, and i realize that he has a much darker complexion than people from say central or northern India. I also have a friend who's from Assam, and when i met her at first i didn't think she was Indian, but i thought perhaps from Burma or Thailand. She had a very oriental phenotype. Then i found out that Indians from north east have such phenotype ; as they're closer to China, Burma, Burma. The people in Punjab, Rajasthan, and Gujarat also have distinct features. The Punjabis , i think, are far more fairer in complexion.
The point im trying to make is, when we first see different people, we tend to make generalizations. But as time goes on, we can see distinctions. It is the beauty of human groups !