Clusters computed from dental development scores of pairs of teeth grouping Atapuerca TD6 hominids with available fossil specimens, African apes (Pan, Gorilla), and living human representatives. Data source: Smith (16). Note that a consistent arrangement becomes visible in the clusters, with hominid 1 from TD6 grouped with H. sapiens specimens and clearly separated from the African apes and Australopithecus representatives. Fossil specimens are designated by their standard abbreviations and classified as follow, Zhou, Zhoukoudian (China) is H. erectus; Gibraltar, Teshik Tash, and Ehringsdorf are Neandertals; Taung, STS, and STW (Sterkfontein) are Australopithecus africanus; LH3 (Laetoli) is Australopithecus afarensis; WT 15000 (West Turkana), ER 1507, and ER 820 (East Rudolf) are H. ergaster; ER 1590 is H. habilis; H. sapiens label designates individual cases. mx, maxilla; md, mandible.