How to cite: Kendrick, James, 2013. Using a morphometric craniodental analysis of Homo habilis to reappraise issues regarding the genus Homo. MSc Dissertation. University of Sheffield, England.

Materials and Methods: Data Collection

James Kendrick made a visit to the Natural History Museum in London (NHML), on

Friday 12th July 2013 to access cast specimens of relevance to this study. Given the uncertain taxonomic status of multiple Homo habilis fossils, certain specimens were of high priority.

Samples (Table 1) were enriched with supplementary casts belonging to the University of

Sheffield’s Department of Archaeology (USHF). These latter specimens comprised of comparative cranial material belonging to Australopithecus africanus (Table 1).

Table 1. Specimens Species Specimen Location H. habilis OH 9 NHML OH 24 NHML KNM-ER 1470 NHML KNM-ER 1805 NHML KNM-ER 1813 NHML KNM-ER 3732 NHML KNM-ER 3733 NHML MLD 37/38 NHML SK 847 NHML MH 1 NHML

A. africanus Sts 5 USHF Sts 71 USHF Stw 505 USHF

Personal measurements (in mm) were made using a combination of digital and spreading callipers. The craniometric measurements taken (Table 2) were a selection of those classically used in phylogenetic studies. Measurements 1 to 24 were taken for specimens located at the Natural History Museum by James Kendrick. The more complete cranial specimens belonging to the University of Sheffield were subjected to additional measurements 25 to 32. Measurements for MH1 were compared to those recorded in Berger et al. (2010: 197-201). Measurements for all other specimens were compared to their counterparts in the Human Origins Database (Wood 1991), except Stw505 for which published data was lacking (see tabulated data sheet).

Table 2. Descriptions of craniometric measurements utilised No. Measurement Relevant landmarks Abbreviations 1 Cranial length Glabella to opisthocranion G-Op, GOC, GOL 2 Cranial height Basion to bregma Ba-Br, BBH 3 Bizygomatic breadth Zygion to zygion Zy-Zy, Bi-Zyg 4 Bijugal breadth Jugion to jugion Ju-Ju, Bi-Jug 5 Bimaxillary breadth Zygomaxillare to zygomaxillare Zm-Zm, Bi-Max, ZMB 6 Bifrontal breadth Frontomalare to frontomalare Fm-Fm, FMB 7 Biorbital breadth Ectoconchion to ectoconchion Ec-Ec, Bi-Orb, EKB 8 Interorbital breadth Dacryon to dacryon Dk-Dk, Int-Orb, DKB 9 Orbital breadth Dacryon to ectoconchion Dk-Ec, Orb-B, OBB 10 Orbital height Maximum vertical orbital height Orb-H, OBH 11 Nasal height Nasion to nasospinale Na-Ns, NLH 12 Nasal aperture height Maximum vertical nasal height in sagittal Nas-H midline 13 Nasal breadth Maximum nasal aperture breadth Nas-B, NLB 14 Cheek height Minimum distance from infraorbital to - maxillary margins 15 Absolute width Maximum breadth of cranium at - whichever point 16 Biporionic breadth Porion to porion Po-Po, Bi-Por 17 Palatal breadth internal Endomolare to endomolare En-En, Pal-I 18 Palatal breadth external Ektomalare to ektomalare Ek-Ek, Pal-E, MAB 19 Superior facial height Nasion to prosthion Na-Pr, NPH 20 Postorbital constriction Minimum frontal breadth posterior to POC orbits 21 Supramastoid breadth Maximum breadth across vault superior to Sm-Sm mastoid process 22 Superior facial length Basion to prosthion Ba-Pr, BPL 23 Basion to Nasion Basion to Nasion Ba-Na, BNL 24 Nasion to Porion Nasion to Porion Na-Po 25 Nasion to Opisthocranion Nasion to Opisthocranion N-Op, NOL 26 Cranial breadth Maximum breadth of cranial vault XCB 27 Frontal breadth Maximum breadth of vault across coronal XFB suture 28 Biasterionic breadth Asterion to asterion As-As, Bi-Ast, ASB 29 Biauricular breadth Distance between roots of zygomatic Bi-Aur, AUB process of temporal 30 Frontal chord Nasion to bregma FRC 31 Parietal chord Bregma to lambda PRC 32 Occipital chord Lambda to opisthion OCC 1. Key: Ae = articular eminence, As = asterion, Ba = basion, Br = bregma, Dk = dacryon, Ec = ectoconchion, En = endomolare, Ek = ektomolare, Fm = frontomalare anterior, G = glabella, Ju = jugion, Na = nasion, Ns = nasospinale, Op = opisthocranion, PG = postglenoid process, Po = porion, POC = postorbital constriction, Pr = prosthion, Sm = supramastoid, SOT = supraorbital torus, Zm = zygomaxillare, Zy = zygion. 2. Measurements defined in Wood (1991) and Wright (2009). Abbreviations in red are used in the Stringer dataset (2013).

Osteological landmarks were defined and identified as in Wood (1991) and Wright

(2009), some of which are portrayed in Figure 1. The majority of measurements and chords were taken parallel or perpendicular to the sagittal midline and along the Frankfort horizontal.

Digital callipers were utilised for the smaller facial and basicranial measurements. Cranial callipers were used for larger measures such as glabella to opisthocranion. Where specimens were fragmentary, measurements were estimated using the basic theory of symmetry. For example, facial measurements such as biorbital breadth were estimated for incomplete crania like Sts71. The distance between ectoconchion and the sagittal midline was recorded.

Biorbital breadth was then calculated as double the previous measurement. Although this method assumes perfect facial symmetry and a lack of distortion to the specimen, it is still likely to be an accurate proxy for the unknown bona fide measurement.

Figure 1. The OH24 cranium in normal frontalis

Annotated osteological landmarks and craniometric measurements in red.

1 = Frontomalare 2= Ectoconchion 3 = Dacryon 4 = Glabella 5 = Nasion 6 = Nasospinale 7 = Prosthion 8 = Zygomaxillare 9 = Bregma 10 = Minimum frontal breadth equivalent to postorbital constriction 11 = Orbital height 12 = Cheek height 13 = Orbital breadth 14 = Nasal (aperture) height 15 = Nasal breadth

Bibliography

Berger, L.R. et al., 2010. Australopithecus sediba: a new species of Homo-like australopith from South Africa. Science 328: 195–204.

Wood B. A. 1991. Koobi Fora Research Project. Volume 4: Hominid Cranial Remains. Oxford, Clarendon Press.

Wright, R., 2009. Guide to using CRANID programs CR6aInd: for linear and nearest neighbours discriminant analysis. Available at: https://www.box.com/shared/h0674knjzl