Both Homo antecessor and Homo heidelbergensis are likely to have descended from the morphologically very similar Homo ergaster from Africa. But because H. heidelbergensis had a larger brain-case – with a typical cranial volume of 1100–1400 cm³ overlapping the 1350 cm³ average of modern humans – and had more advanced tools and behavior, it has been given a separate species classification.[18] "The anatomy [of H. heidelbergensis] is clearly more primitive than that of Neanderthal, but the harmoniously rounded dental arch and the complete row of teeth...already typically human.