DOI: 10.5061/dryad.stqjq2c1b
title: Landmarks and 3D scan data of Macaca fascicularis

description: Objectives: Magnitudes of morphological integration may constrain or
 facilitate craniofacial shape variation. The aim of this study was to
 analyze how the magnitude of integration in the skull of Macaca
 fascicularis changes throughout ontogeny in relation to developmental
 and/or functional modules. Materials and Methods: Geometric morphometric
 methods were used to analyze the magnitude of integration in the macaque
 cranium and mandible in 80 juvenile and 40 adult M. fascicularis
 specimens. Integration scores in skull modules were calculated using ICV
 (Integration Coefficient of Variation of eigenvalues) based on a
 resampling procedure. Resultant ICV scores between the skull as a whole,
 and developmental and/or functional modules were compared using
 Mann-Whitney U tests. Results: Results showed that most skull modules were
 more tightly integrated than the skull as a whole, with the exception of
 the chondrocranium in juveniles without canines, the chondrocranium/face
 complex and the mandibular corpus in adults, and the mandibular ramus in
 all juveniles. The chondrocranium/face and face/mandibular corpus
 complexes were more tightly integrated in juveniles than adults, possibly
 reflecting the influences of early brain growth/development, and the
 changing functional demands of infant suckling and later masticatory
 loading. This is also supported by the much higher integration of the
 mandibular ramus in adults compared with juveniles. Discussion: Magnitudes
 of integration in skull modules reflect developmental/functional
 mechanisms in M. fascicularis. However, the relationship between
 ‘evolutionary flexibility’ and developmental/functional mechanisms was not
 direct or simple, likely because of the complex morphology,
 multifunctionality, and various ossification origins of the skull.
description: For this study, 80 juvenile and 40 adult <i>M.
 fascicularis</i> skeletal specimens were used. When they were alive,
 these specimens were used for biomedical research, and their skeletal
 remains are housed in the Department of Anthropology of the University at
 Buffalo, SUNY. Age groups were partitioned based on mandibular dental
 developmental stages, with juvenile specimens divided into two groups:
 with or without permanent canines. This division is based on the results
 of previous studies that showed changes in the skull tended to be most
 distinct around the eruption of permanent canines in <i>M.
 fascicularis</i> (Mouri, 1994, 1996). Adult specimens were defined
 according to the full eruption of entire mandibular dentition to occlusion
 and a fully fused spheno-occipital synchondroses. Thus, shape changes were
 analyzed among two juvenile groups and one adult group.
 In order to conduct geometric morphometric analyses, crania and
 mandibles of <i>M</i>. <i>fascicularis</i>
 specimens were scanned with an HDI Advance high definition 3D scanner (LMI
 Technologies INC., Vancouver, Canada.). To capture the shape of objects,
 midline and bilateral landmarks were applied with reference to Smith
 & von Cramon-Taubadel (2015). Landmarks not defined by Smith
 & von Cramon-Taubadel (2015) were added due to the different
 cranial and mandibular shapes between juvenile and adult groups (Table 2).
 These landmarks were digitized in Landmark Editor (Wiley et al., 2005) by
 a single researcher (HJ). For intra-observer error assessment, one cranium
 and one mandible were digitized three times and error was calculated in
 millimeters for each landmark. This error assessment method calculates
 errors based on standard deviations among coordinates of landmarks on 3D
 models because each scan shares the same fixed coordinated plane (von
 Cramon-Taubadel et al., 2007).