In Dmanisi, a paleolithic site in Georgia, that is 1.85 million years old, a fifth skull was found, D4500, and a mandible, D2600. The brain case was small, 546 cc . There is a great similarity with this skull and those from that period in Africa.
The skull has the largest face, the most massive jaws and teeth and the smallest brains of the five Dmanisi-skulls. The skull and ma,dible were extraordinarily well preserved. The variation within the five Dmanisi humans is, according to the researchers, the same as between early East African specimen of Homo.
Marcia Ponce de León, one of the researchers of D4500, made a point about the number of human species, between 2.4 and 1.8 million years ago. It is generally assumed that there were four types: Homo habilis, Homo rudolfensis, Homo ergaster and Homo erectus. “First, the individuals of Dmanisi all belong to a population of a single, early homo species. Secondly, the five individuals of Dmanisi are strikingly different from each other, but not five any more differently than modern human individuals or five chimpanzees of a given population.” according to her it establishes that there was only one human species, albeit with much variation. de Léon chooses to name it Homo erectus.
David Lordkipanidze, Marcia S. Ponce de León, Ann Margvelashvili, Yoel Rak, G. Philip Rightmire, Abesalom Vekua, and Christoph P.E. Zollikofer, ‘A complete skull from Dmanisi, Georgia, and the evolutionary biology of early Homo’, Science, October 18, 2013. doi: 10.1126/science.1238484
Ann Margvelashvili, Christoph P. E. Zollikofer, David Lordkipanidze, Timo Peltomäki, Marcia S. Ponce de León, ‘Tooth wear and dentoalveolar remodeling are key factors of morphological variation in the Dmanisi mandibles’, Proceedings of the National Academy of Sciences, September 2, 2013. doi: 10.1073/pnas.1316052110
ABout the finds in Dmanisi, in Dutch : Marc Vermeersch. De geschiedenis van de mens. Deel I. Jagers en verzamelaars.Boek 1, van Pan tot Homo sapiens, p.114.