How to infer where a white person’s ancestors come from based on his appearance?

If I only see a white man’s face, I really can’t guess which country he is from. He may be European, he may be American or Canadian, he may also be Australian, New Zealand or South African. Only by listening to his accent can I guess where he is from more accurately. In fact, several characteristics of white people have geographical distribution trends, such as red hair. The distribution map below shows the frequency of red hair in Europe. If you see a man with red hair, he is most likely from Ireland, Scotland, or Wales. But it may also be from France, the Netherlands, Germany, Sweden, Russia and other countries. The geographical distribution of yellow hair is also patterned. The distribution map below shows that yellow hair is most common in the Nordic countries of Norway, Sweden, and Finland, while it is rare in Spain and Italy. With this awareness, if I see a person with yellow hair, I can guess that he is Nordic, but I cannot be sure. Moreover, he is most likely of Northern European descent in the United States, and you can't tell just by looking at his appearance. There are a few more characteristics: Blue eyes are mainly found in Northern Europe. Take me for example. According to the diagram above, you might guess that I am Swedish. Yes, I am Swedish-American. White people also have a wide range of skin colors. Northern Europeans have a relatively "white" complexion, while southern Europeans have a relatively "dark" complexion. Here we need to correct what the Chinese people often call "black". Southern Europeans and some ethnic minorities in China are not called black. Black generally can only refer to Africans, as well as some indigenous people in Australia and America. We are accustomed to calling the color in the middle of the lower stand "tan" (tawny). I saw other answers mentioned features such as chin and nose. I personally can't tell these apart and never pay attention. Finally, post a related schematic diagram. These 40 women are not real people, but are representatives of the "average women" in 40 countries. They manipulated the effect by collecting avatars of many different women from various countries.