Talk:Mary Sue/Image Gallery/@comment-38739331-20191110015521/@comment-149.4.115.14-20200309180258

Because in terms of geography, their home countries are next to each other and would have high chance of genes with similar if not outright same ancestry. Its like asking why white people in the US are caucasian like the white people in Europe.

If you mean why anime and other media depict her with different hair color. Artistic license and because a long standing tradition in anime that important characters which usually look alike due to having the same artist are distinct enough to identify which usually explains crazy hair colors like blue and green. Look up Adaptation Dye Job and You Gotta have Blue Hair