Sometimes…but context can make a big difference.
For instance, suppose you were in Nanjing (say) and you guessed that every Thai-looking person you saw was actually from Thailand. What sort of success rate do you think you would have, in that situation?
A friend of mine has said that people talked to her in Chinese when she was in China and she is Peruvian.
I’m Filipino and many Asians (including fellow Filipinos) have a hard time correctly identifying where I’m from. It can be a fun game and they seem to enjoy trying to guess. I’ve also had many non-Filipino Asians start speaking to me in their native tongue. I once had Chinese food in Manhattan eons ago and the woman (Chinese, I guess) behind the counter was really struggling to figure me out, finally settling on Russian before I told her the truth.
My father’s family tends to have more traditional Filipino features but my mother’s family has more Spanish influenced features (my grandfather had blue eyes); she would be what we would call ‘mestiza’. The combination of these is probably what throws people off. OTOH, there have been some who’ve identified me correctly at one glance.
I’ve heard some characterize Koreans as having ‘box-y’ faces.
FWIW I scored a 4 on that All Look Same exam. I tend to agree that the exam is rigged to throw you off, although I can’t say I’m an expert at spotting the differences in real life anyway.
I assume you are excluding the Thai’s that are ethnic Chinese. 
I think in Nanjing that Thai’s would stick out like a sore thumb. Honestly, in Nanjing most Chinese Americans would stick out. If we were in Nanjing, I could look for all sorts of clues in dress, personal space, mannerisms, types of muscles, etc. that would provide additional clues to just the facial appearance.
Being in a place with a dominant race (such as Han China), it is much more straightforward to identify someone not from there. It is analogous to the seeing a tall blonde nordic in Greece. It’s possible the tall blonde has 100% Greek ancestry back for generations and generations, but
Ah, ‘making desktop wallpapers’ is what they’re calling it these days, huh? 28 and I’m already out of touch with the hip jive.
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Hmmmm… this thread. I agree that there are certain, rare faces that one could not mistake (for example I would never think Lucy Liu was Japanese). Furthermore, I still think one can make an educated guess about this thing. Of course, in reality, clothing and manner also make a big impression. Lastly, one must never forget about the possibility for spectacular fail. It’s never a good idea to go off one’s assumptions in this matter.
One small point for discussion, coming from somebody who lives in Japan. Korean women in Japanese media seem much curvier, more vivacious, more sexy. My experience with Korean women in general has been that they have a much more hourglass-esque figure, but I could very well be seeing only what I want to see. (And how.)
Oh, and another thing. My GF often gets asked whether she is Korean or Chinese. Meh.
And they always seem to be taking bubble baths!
Or driving taxis.
I have yet to meet anyone who can reliably distinguish between third or fourth generation Japanese-, Korean- or Chinese-Americans. I’ve tested Japanese friends visiting the States, and have never gotten anything better than random
As is anyone who have lived for a good number of years in East Asia, I can (usually) pick out the natives, usually assisted by clothes, hair styles, hand bags, etc.
But I always enjoy these threads. Carry on.
My Thai wife is actually ethnically Chinese. And she has been mistaken by other Thais at various times for Japanese and Filipina.
No, seriously. I had a web site for them and everything for 3-4 years (600,000+ hits before I got tired of making wallpapers and took it down). I once even had a professional graphic designer e-mail to tell me that my typography was better than what he’d seen from many professional graphic designers 
Here’s one of the many I made: http://www.mister-rik.com/hosted/rie_mashiko_05.jpg
(should be SFW)
Right…but I would also guess that the number of Chinese who look Thai-ish (due to some fluke of genetics) probably exceeds the number of Thais who live there. So you’d end up with a good number of false positives.
Of course, now someone’s going to slap me in the face with the fact that Nanjing has the largest Thai population outside of Bangkok or something.
No, actually that’s Los Angeles, with an estimated 80,000 as of 2002.
But there is at least one place in southern China where I believe the locals are ethnic Thais. (Forgive me if this was mentioned above and I missed it.) Can’t remember where, but the language they speak is pretty much colloquial Thai, and I’ve heard of Thais from Thailand being blown away encountering them, as folks here are pretty nationalistic and don’t figure on running into anything like that.
Certain hilltribes in northern Vietnam also share a similar heritage, but they’re more like distant cousins.
The Dai, who live in Xishuangbanna near the Burmese and Cambodian border. Are the ethnic Thai’s you are thinking of.
Regarding the hilltribes, the Hmong (in China known as the Miao) are spread out on both sides of the border.
The Miao and the Dai are pretty obviously non Han Chinese. Especially if dressed in their traditional clothing. First time I saw a Miao was in Guiyang, the sleepy little capital of Guiyang province 25 years ago. There are a lot of non-Han Chinese minority groups in the province and I had just gotten off the train back in the days of proletarian everyone dressed in blue or green drab baggy clothing. Walking down the street were three women under 5’ tall with what looked like devil horns and some very colorful homespun and dyed clothing. I was thinking WTF as they stopped slack jawed staring at this white guy (there were very few foreigners those days that ever went to Guiyang). They spoke maybe 5 words of mandarin, couldn’t resist touching my hairy arms and thought it was hilarious when I pulled up a trouser leg to show an even hairier whiter leg. We kinda checked each other out for a while, smiled and went on our respective merry ways. They didn’t want to be photographed and I always regret not having a picture of that encounter. I have not been able to find a photo that is similar (search on long horned Miao turns up a different group of Miao with a different hair style. But even without the traditional dress, one should be able to notice a marked difference between a typical Miao or Dai when compared with a Han-Chinese.
I guess to mix the genetic waters, Ghengis Khan built an empire in more than one way: nearly 8 percent of the men living in the region of the former Mongol empire carry y-chromosomes that are nearly identical.
Anything like this?
(Koreans, BTW)
or they could be one of the 237 million Indonesians
Ah, but the northern Thai are renowned for their light skin. Often milky white. The other Thais consider them the most beautiful and cannot understand why Westerners all seem to go for the dark-skinned Northeasterners.
Bingo! That’s them.
We have them in Thailand too, in the North.
No, it was quite literally like goat horns. As in stereotypical “devil” looking. The 'Horns" were wooden and likely to be part of a frame for wrapping their to the ankle long hair around. It was just surreal back in those days being a solo Western backpacker running into tribal folk who had obviously never seen a westerner before.
Here’s a linkto some older Miao women. Searching on “horn miao” photos. Another photowhich shows the “horn” as a frame for wrapping the long hair around. However, none of the photos are close.
I think there may be something to that. I remember that there have been pretty well documented changes in Japanese people’s stature and appearance due to changes in diet and living style (introduction of protein and chairs).
