title: The skull of Homo naledi.
abstract: The species Homo naledi was recently named from specimens recovered from the Dinaledi Chamber of the Rising Star cave system in South Africa. This large skeletal sample lacks associated faunal material and currently does not have a known chronological context. In this paper, we present comprehensive descriptions and metric comparisons of the recovered cranial and mandibular material. We describe 41 elements attributed to Dinaledi Hominin (DH1-DH5) individuals and paratype U.W. 101-377, and 32 additional cranial fragments. The H. naledi material was compared to Plio-Pleistocene fossil hominins using qualitative and quantitative analyses including over 100 linear measurements and ratios. We find that the Dinaledi cranial sample represents an anatomically homogeneous population that expands the range of morphological variation attributable to the genus Homo. Despite a relatively small cranial capacity that is within the range of australopiths and a few specimens of early Homo, H. naledi shares cranial characters with species across the genus Homo, including Homo habilis, Homo rudolfensis, Homo erectus, and Middle Pleistocene Homo. These include aspects of cranial form, facial morphology, and mandibular anatomy. However, the skull of H. naledi is readily distinguishable from existing species of Homo in both qualitative and quantitative assessments. Since H. naledi is currently undated, we discuss the evolutionary implications of its cranial morphology in a range of chronological frameworks. Finally, we designate a sixth Dinaledi Hominin (DH6) individual based on a juvenile mandible.
authors.affiliation: Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA; Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa. Electronic address: lairdm@uchicago.edu.
authors.forename: Myra F
authors.initials: MF
authors.lastname: Laird
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Anthropology, University at Buffalo, SUNY, NY 14261, USA; Department of Archaeology, University of Cape Town, Rondebosch 7701, South Africa; Human Evolution Research Institute, University of Cape Town, Rondebosch 7701, South Africa.
authors.forename: Lauren
authors.initials: L
authors.lastname: Schroeder
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Applied Forensic Sciences, Mercyhurst University, Erie, PA 16546, USA; Department of Anthropology/Archaeology, Mercyhurst University, Erie, PA 16546, USA.
authors.forename: Heather M
authors.initials: HM
authors.lastname: Garvin
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Anthropology, The University of Iowa, Iowa City, IA 52242, USA; Department of Sociology and Anthropology, Metropolitan State University of Denver, CO 80217, USA.
authors.forename: Jill E
authors.initials: JE
authors.lastname: Scott
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Archaeology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; Human Evolutionary Studies Program, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
authors.forename: Mana
authors.initials: M
authors.lastname: Dembo
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Geology and Paleontology, Croatian Natural History Museum, Demetrova 1, 10000 Zagreb, Croatia.
authors.forename: Davorka
authors.initials: D
authors.lastname: Radovčić
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Anthropology, University of Colorado Denver, CO 80217, USA.
authors.forename: Charles M
authors.initials: CM
authors.lastname: Musiba
authors.affiliation: Department of Archaeology, University of Cape Town, Rondebosch 7701, South Africa; Human Evolution Research Institute, University of Cape Town, Rondebosch 7701, South Africa.
authors.forename: Rebecca R
authors.initials: RR
authors.lastname: Ackermann
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Anthropological Institute and Museum, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Schmid
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Anthropology, University of Wisconsin - Madison, Madison, WI 53593, USA.
authors.forename: John
authors.initials: J
authors.lastname: Hawks
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa.
authors.forename: Lee R
authors.initials: LR
authors.lastname: Berger
authors.affiliation: Evolutionary Studies Institute and Centre for Excellence in PaleoSciences, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa; Department of Anthropology, Texas A&M University, College Station, TX 77843, USA. Electronic address: deruiter@tamu.edu.
authors.forename: Darryl J
authors.initials: DJ
authors.lastname: de Ruiter
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005580:Fossils / Q000033:anatomy & histology*; D015186:Hominidae / Q000033:anatomy & histology*; D008334:Mandible / Q000033:anatomy & histology*; D012886:Skull / Q000033:anatomy & histology*; D013019:South Africa
keywords: Cranial and mandibular variation; Dinaledi; Homo; Rising Star cave system; South Africa