Why was africanus unlike any primate fossil skull that Dart had ever seen?

The skull of _Australopithecus africanus_ was unlike any primate fossil skull that Dart had ever seen because of its combination of ape-like and human-like features. The skull had a small braincase and a projecting jaw, typical of apes, but it also had a relatively flat, human-like face and small canine teeth. This combination of features suggested that _A. africanus_ was an intermediate form between apes and humans.