That is an implication of unpublished research using macaque monkeys by Doris Tsao and Winrich Freiwald, of the University of Bremen, in Germany.

ECONOMIST: Facial characteristics

The latest controversy surrounding Germany's charismatic defence minister emerged when a Bremen University law professor began writing a review of the dissertation which was published two years ago, with the aid of internet search engines.

BBC: German minister denies plagiarism on PhD thesis