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Abstracts / HOMO - Journal of Comparative Human Biology 61 (2010) 204–222 219
Measuring human facial variation using 3D scanning and mapping
R.V. Taylor a,b, P. Claes a, J.G. Clement a, (a The University of Melbourne, Victoria, Australia andb Marcellin College, Bulleen, Australia), [email protected]
Description and assignment of individuals to specific populations is of significant interest to anthro-pologists, clinicians and forensic scientists. This research investigated the use of 3D facial images tocreate an unbiased, objective system for such tasks. Results were compared with each individual’sself-perception of ancestry and gender.
Facial image acquisition was undertaken using a non-contact 3D surface scanner. The data were rep-resented as an automatically generated dense set of landmarks which, with mathematical modeling,provided correspondence between homologous features for all the individuals in the study.
Using this approach, the construction of population representatives was feasible. These archetypeswere used to compare and depict areas of variation between homologous features of different groupsallowing a quick analysis. Automated classification algorithms were derived from Principal ComponentModeling. These were used to study the variation within the population around the archetype.
Overall concordance between automated classification and declared ancestry and gender was 95%(195 of 206). No incorrect classification of an individual into a group that did not share at least onevariable, either gender or self-perceived ancestry occurred.
This analysis of 3D facial images is a model for the visualization and description of other populationsand the affinities between them.
doi:10.1016/j.jchb.2010.01.038
Aspects of cervical vertebral growth and dental development in New Zealand children
K.A. Timmins, J.A. Kieser, W.J. Harding, W.M. Whomson, (The University of Otago, Dunedin, NewZealand), [email protected]
Growth and development standards for children are important in the fields of orthodontics, pae-diatric dentistry, archaeology and forensic odontology. Assessment of the chronology of a child’sdevelopment requires normative reference standards so that a given physiological age can becompared to chronological age. While dental age has traditionally been determined by either the emer-gence or calcification of teeth, skeletal age determination has rested upon hand–wrist radiographs and,most recently, the radiological appearance of the cervical spine (Cervical Vertebral Maturation). Thisstudy assesses the relationship between two measures of dental maturation (namely the Demirjianand Cameriere methods) and the relationship between dental maturation and skeletal maturation(assessed using the cervical spine) in a sample of New Zealand children.
doi:10.1016/j.jchb.2010.01.039
A fine-grained analysis of Maori and Pakeha mortality patterns in remote settlements in thecolonial society of New Zealand from 1850 to 1950, using genealogical/whakapapa information
S. Wallace, (The University of Auckland, New Zealand), [email protected]
Historical mortality analysis in New Zealand has largely depended upon the use of nationwidestatistics. This method of analysis raises questions concerning the specificity of derived statistics andlack of meaningful detail. Suspected poor levels of death registration, limited information on causeof death and questions of representativeness of national statistics to sub-regions, are all reasons toinvestigate more fully mortality data in New Zealand. My study will investigate causes of mortalitytaken from death registration records and combine these with genealogical family reconstructions tobetter contextualise data collected.
Two coastal communities of Tolaga Bay and Little Akaloa were used for family reconstructions. Thehistories of these families and their mortality patterns were followed from 1850 to 1950 to examinepossible social and biological processes underlying mortality changes occurring from the colonial
220 Abstracts / HOMO - Journal of Comparative Human Biology 61 (2010) 204–222
period through to the first half of 20th century. Preliminary results suggest a major contrast in levelsof registration of births, marriages, and deaths between Maori and Pakeha. These findings depart fromprevious reports in suggesting differences well into the 20th century. This study also finds relationshipsbetween occupational-related deaths and suicides of single men and differences between the twocommunities in marriage rates, family support and occupation risks. Findings also call into questionthe extent and accuracy of mortality data officially reported during the 1918 Influenza epidemic.
doi:10.1016/j.jchb.2010.01.040
High-dimensional statistical analysis of three-dimensional facial images in the treatment ofcraniofacial dysmorphologies at PMH
M. Walters a, P. Claes b, J. Clement b, P. Sillifant a, D. Gillett a, (a Princess Margaret Hospital for Children,Perth, WA, Australia and b Melbourne Dental School, Victoria, Australia),[email protected]
The treatment objectives for reconstructive procedures in children with craniofacial dysmorpholo-gies are to achieve normality. Currently ‘normality’ is defined by a set of averaged facial anthropometricdata either based on averaged distances of skeletal landmarks retrieved from plain head films or facialanthropometrics. The advent of high dimensional capture of facial profile with three-dimensionalsurface scanners, computing power and geometric morphometrics has facilitated a statistical analy-sis of spatial relationships of faces. In collaboration with the Cranio-Maxillo-Facial Unit at PMH andthe Melbourne Dental School we have established the first objective means to generate virtual three-dimensional ‘normalised’ facial profiles of patients (a normal equivalent) to be used as a primarysurgical objective in cranio-maxillo-facial reconstructive procedures.
This has been achieved by ‘mapping’ a patient’s 3D image to a reference range that is referred to asa ‘normative face space’. The patient ‘mapped’ facial manifold is statistically fitted to the normal facespace to establish the confidence limits of variation for all vertices (9000 pts). By applying threshold-ing to these confidence intervals the dysmorphic parts of the face can be isolated and colour codedimages/maps generated that assist the treating clinician to define the problem. The use of statisticalgenerated normal equivalent patient images is rapidly being introduced into clinical practice, despitebeing still in a development phase.
doi:10.1016/j.jchb.2010.01.041
Functional morphology of the macropod temporomandibular joint
M. Walters a,b, N. Warburton a,c, (a Murdoch University, Western Australia, Australia and b PrincessMargaret Hospital for Children, Perth, Western Australia, Australia and c Western Australian Museum,Perth, Australia), [email protected]
The temporomandibular joint (TMJ) is a defining feature of the masticatory apparatus of mammals,in which the mandibular condyle articulates with the squamous temporal bone of the skull. Strikingdifferences in TMJ morphology exist between taxa and reflect both phylogeny and the different pro-cessing requirements of contrasting diets. The morphological configurations of the articular surfacesreflect varying degrees of mandibular mobility and stability during the masticatory cycle.
This paper describes the TMJ anatomy of kangaroos, wallabies and rat kangaroos, as part of alarger study of macropod masticatory apparatus. Macropods are a diverse group of herbivores thatcan be characterised into distinct feeding groups; grazers, browsers and mixed feeders. Skulls from22 species of kangaroos were scanned by a laser scanner to retrieve three-dimensional data. TMJ mor-phology, including articular surfaces, principal axes of rotation and shape were extracted. Considerablevariation in TMJ morphology was found.
Browsers were characterised by small rounded condyles and a principal axis that is consistentwith a predominately hinging action with a limited rotation about the mental symphysis. Grazers,by contrast had condyles with a large surface area with a distinctive concavity that had elliptical
