Although Omo 18 was the first skull discovered of these species, many paleoanthropologists ignored the finding on the basis that it was similar to the other species of australopithecines.
Iako je Omo 18 bio prva otkrivena lubanja te vrste, mnogi paleoantropolozi ignorirali su to otkriće na temelju toga da je sličan jednoj drugoj vrsti australopitecina.