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Since the beginning of the Holocene, the Anatolian region has been a crossroads for populations and civilizations from Europe, Asia, and the Near to Middle East, with increasing interactions since the Bronze Age. In this context, we examine cranial discrete traits from a Byzantine population from southwest Turkey, excavated at the archeological site of Sagalassos; the site displays human occupation since the 12th millennium B.P. To investigate the biological history of this population, we analyzed the frequency distribution of 17 cranial discrete traits from Sagalassos and 27 Eurasian and African populations. Ward's clustering procedure and multidimensional scaling analyses of the standardized mean measure of divergence ([MMD.sub.st]), based on trait frequencies, were used to represent the biological affinity between populations. Our results, considered within a large interpretive framework that takes into account the idea that populations are dynamic entities affected by various influences through time and space, revealed different strata of the Sagalassos biological history. Indeed, beyond an expected biological affinity of the Sagalassos population with eastern Mediterranean populations, we also detected affinities with sub-Saharan and northern and central European populations. We hypothesize that these affinity patterns in the Sagalassos biological package are the traces of the major migratory events that affected southwest Anatolia over the last millennia, as suggested from biological, archeological, and historical data. KEY WORDS: CRANIAL DISCRETE TRAITS, BIODISTANCE ANALYSIS, MEAN MEASURE OF DIVERGENCE, BYZANTINE POPULATION, SAGALASSOS, ANATOLIA., Since the beginning of the Neolithic period, the eastern part of the Mediterranean basin and especially the Anatolian region, has been an area of interaction between cultures and populations from [...]

The house mouse is one of the most successful mammals and the premier research animal in mammalian biology. The classical inbred strains of house mice have been artificially modified to facilitate identification of the genetic factors underlying phenotypic variation among these strains. Despite their widespread use in basic and biomedical research, functional and evolutionary morphologists have not taken full advantage of inbred mice as a model for studying the genetic architecture of form, function, and performance in mammals. We illustrate the potential of inbred mice as a model for mammalian functional morphology by examining the genetic architecture of maximum jaw-opening performance, or maximum gape, across 21 classical inbred strains. We find that variation in maximum gape among these strains is heritable, providing the first evidence of a genetic contribution to maximum jaw-opening performance in mammals. Maximum gape exhibits a significant genetic correlation with body size across strains, raising the possibility that evolutionary increases in size frequently resulted in correlated increases in maximum gape (within the constraints of existing craniofacial form) during mammalian evolution. Several craniofacial features that influence maximum gape share significant phenotypic and genetic correlations with jaw-opening ability across these inbred strains. The significant genetic correlations indicate the potential for coordinated evolution of craniofacial form and jaw-opening performance, as hypothesized in several comparative analyses of mammals linking skull form to variation in jaw-opening ability. Functional studies of mammalian locomotion and feeding have only rarely examined the genetic basis of functional and performance traits. The classical inbred strains of house mice offer a powerful tool for exploring this genetic architecture and furthering our understanding of how form, function, and performance have evolved in mammals.

The cranial base is one of the major foci of interest in functional craniology. The evolution and morphogenesis of this structure are still poorly known and rather controversial because of multifactorial influences and polyphasic stages. Endocranial dynamics are associated anteriorly with the upper facial structures, laterally with the mandibular system and midsagittally with brain development. In the present study, we investigated the endocranial morphology of modern humans using 3D landmark-based approaches, i.e. geometric morphometrics and Euclidean distance matrix analysis. The structure of endocranial variation is poorly integrated, with only weak reciprocal influences among the three fossae. Some major variations are associated with changes in the posterior fossa, with possible consequences on the anterior areas. These main patterns of integration are hypothesized to be influenced by the connective tensors of the dura layers. Static allometry and sex differences are largely related to the ontogenetic sequences, characterized by early maturation of the anterior fossa with respect to the middle and posterior regions (i.e., relatively shorter posterior part of the planum sphenoideum and vertical lengthening of the clivus in males). The relative independence between the endocranial fossae, as well as their structural connection through the meningeal tensors, must be carefully considered in studies on the evolutionary dynamics, since they lead to mosaic changes through phylogeny. KEY WORDS cranial base; endocranial fossae; functional craniology; morphological integration

Re-description of the left dentary of Chinshakiangosaurus chunghoensis reveals that it possesses an unusual combination of 'prosauropod' and 'sauropod' character states. Cladistic analysis places Chinshakiangosaurus as one of the most basal sauropods known currently. Mapping of dentary and dental characters onto the most parsimonious topologies yields insights into the sequence of acquisition of a number of feeding-related characters. For example, it seems that basal sauropodomorphs (traditional prosauropod taxa) possessed a fleshy cheek that attached to the mandible along a marked ridge, and that the same structure was present in the most basal sauropods. The early sauropod skull developed a lateral plate that reinforced the bases of the tooth crowns labially, and had wrinkled tooth enamel and a concavity on the mesial portion of the lingual part of each crown, while retaining a fleshy cheek and a relatively weak symphysis. More advanced sauropods (eusauropods) lost the cheek, perhaps in order to increase the gape of the jaws in response to a change in feeding style that involved collection of larger quantities of poor quality foliage. Keywords: dentary, Dinosauria, phylogeny, Sauropoda, Sauropodomorpha.

The Ceprano calvarium represents one of the most important sources of information about both the dynamics of the earliest hominid dispersal toward Europe and the evolution of the genus Homo in the early-to-middle Pleistocene. In this paper, the midsagittal vault profile and the 3D frontal bone morphology of Ceprano are investigated comparatively, using landmark coordinates and Procrustes superimposition. In fact, despite the fact that the skull appears partially distorted by diagenetic pressures (thus precluding a comprehensive landmark-based analysis), some aspects of the overall morphology are suitable for consideration in terms of geometric morphometrics. The midsagittal profile shows an archaic shape, comparable with the H. ergaster/erectus range of variation because of the fronto-parietal flattening, the development of the supraorbital and nuchal structures, and the occurrence of a slightly larger occipital bone. By contrast, the frontal bone displays a derived 3D shape that, mostly because of the widening of the frontal squama, appears comparable with the Afro-European variation of the Middle Pleistocene (i.e., H. heidelbergensis/rhodesiensis). Taking into account the unique morphological pattern displayed by Ceprano, its role as a link between early Homo and the Middle Pleistocene populations of Europe and Africa is not falsified. Thus, when aspects of the Ceprano's morphology are described within the analytical framework provided by geometric morphometrics, the relationships between Ceprano and the subsequent Afro-European fossil record are emphasized, suggesting the occurrence of an ancestral stock of H. heidelbergensis/ rhodesiensis that is properly represented by the Italian specimen. KEY WORDS cranial morphology; geometric morphometrics; human evolution; Homo; Europe

FOXL2 is a gene encoding a forkhead transcription factor, whose mutations are responsible for the blepharophimosis- ptosisepicanthus inversus syndrome that often involves premature ovarian failure. FOXL2 is one of the earliest ovarian markers and it offers, along with its targets, an excellent model to study ovarian development and function in normal and pathological conditions. We have recently shown that the aromatase gene is a target of FOXL2, and only three other targets have been reported so far. To detect potential transcriptional targets of FOXL2, we used DNA chips and quantitative PCR to compare the transcriptomes of granulosa-like cells overexpressing, or not, FOXL2. This analysis showed that mediators of inflammation, apoptotic and transcriptional regulators, genes involved in cholesterol metabolism, and genes encoding enzymes and transcription factors involved in reactive oxygen species detoxification were up-regulated. On the other hand, FOXL2 down-regulated the transcription of several genes involved in proteolysis and signal transduction and in transcription regulation. A bioinformatic analysis was conducted to discriminate between potential target promoters activated and repressed by FOXL2. In addition, the promoters of strongly activated genes were enriched in forkhead recognition sites, suggesting that these genes might be direct FOXL2 targets. Altogether, these results provide insight into the activity of FOXL2 and may help in understanding the mechanisms of pathogenesis of FOXL2 mutations if the targets prove to be the same in the ovary. forkhead | infertility | premature ovarian failure | ovary

Between 2003 and 2005, the Pestera cu Oase, Romania yielded a largely complete early modern human cranium, Oase 2, scattered on the surface of a Late Pleistocene hydraulically displaced bone bed containing principally the remains of Ursus spelaeus. Multiple lines of evidence indicate an age of [approximatelt equal to] 40.5 thousand calendar years before the present ([approximatelt equal to] 35 ka [sup.14]C B.P.). Morphological comparison of the adolescent Oase 2 cranium to relevant Late Pleistocene human samples documents a suite of derived modern human and/or non-Neandertal features, including absence of a supraorbital torus, subrectangular orbits, prominent canine fossae, narrow nasal aperture, level nasal floor, angled and anteriorly oriented zygomatic bones, a high neurocranium with prominent parietal bosses and marked sagittal parietal curvature, superiorly positioned temporal zygomatic root, vertical auditory porous, laterally bulbous mastoid processes, superiorly positioned posterior semicircular canal, absence of a nuchal torus and a suprainiac fossa, and a small occipital bun. However, these features are associated with an exceptionally flat frontal arc, a moderately large juxtamastoid eminence, extremely large molars that become progressively larger distally, complex occlusal morphology of the upper third molar, and relatively anteriorly positioned zygomatic arches. Moreover, the featureless occipital region and small mastoid process are at variance with the large facial skeleton and dentition. This unusual mosaic in Oase 2, some of which is paralleled in the Oase 1 mandible, indicates both complex population dynamics as modern humans dispersed into Europe and significant ongoing human evolution once modern humans were established within Europe. cranium | dentition | Neandertals | Upper Paleolithic

Morphological integration and modularity are important points of intersection between evolution and the development of organismal form. Identification and quantification of integration are also of increasing paleoanthropological interest. In this study, the 'posterior face,' i.e., the mandibular ramus and its integration with the associated midline and lateral basicranium, is analyzed in lateral radiographs of 144 adult humans from three different geographic regions. The null hypothesis of homogenously pervasive morphological integration among 'posterior-face' components is tested with Procrustes geometric morphometrics, partial least squares, and singular warps analysis. The results reveal statistically significant differences in integration. Only loose integrative relationships are found between midline and lateral components of the basicranium, which may indicate the presence of at least two different basicranial modules. This modularity can be interpreted in terms of spatiotemporal dissociation in the development of those basicranial structures, and gives support to hypotheses of independent phylogenetic modifications at the lateral and midline basicranium in humans. In addition, morphological integration was statistically significantly stronger between the middle cranial fossa and the mandibular ramus than between the ramus and the midline cranial base. This finding confirms previous hypotheses of a 'petroso-mandibular unit,' which could be a developmental consequence of well-known phylogenetic modifications in coronal topology of the posterior face and base in hominoid evolution, related to middle cranial fossa expansion. This unit could be involved in later evolutionary tendencies in the hominid craniofacial system. Am J Phys Anthropol 128:26-34, 2005. KEY WORDS craniofacial biology; covariation; evolutionary development; partial least squares; singular warps; Procrustes; geometric morphometrics

Based on an analysis of nonmetric trait databases from several large skeletal series in Northern Europe and South America, representing 27 bilateral traits, we report a predictable relationship between the frequency of nonmetric traits and the probability that they are expressed bilaterally. In a wider sampling of traits and populations, this study thus confirms the findings of an earlier study by Ossenberg ([1981] Am. J. Phys. Anthropol. 54:471-479), which reported the same relationship for two mandibular traits. This trend was previously explained by extending the multifactorial threshold model for discontinuous traits to incorporate either separate thresholds for unilateral or bilateral expression, or by a fuzzy threshold in which the probability of bilateral expression increases away from the median threshold value. We show that the trend is produced under the standard multifactorial threshold model for discontinuous traits simply if the within-individual or developmental instability variance remains relatively constant across the range of liability. Under this assumption, the number of individuals in which one side but not the other is pushed over the threshold for trait formation will be a larger proportion of the number of individuals expressing the trait when the trait frequency is low. As trait frequency increases, the significance of within-individual variance as a determinant of trait formation decreases relative to the genetic and among-individual environmental variance. These results have implications for interpreting nonmetric trait data as well as for understanding the prevalence of unilateral vs. bilateral expression of a wide variety of discontinuous traits, including dysmorphologies in humans. Am J Phys Anthropol 128:14-25, 2005. KEY WORDS nonmetric traits; threshold traits; fluctuating asymmetry; dysmorphology; variability

Laterality is fundamental to the vertebrate body plan. Here, we investigate the roles of fgf8 signaling in LR patterning of the zebrafish embryo. We find that fgf8 is required for proper asymmetric development of the brain, heart and gut. When fgf8 is absent, nodal signaling is randomized in the lateral plate mesoderm, leading to aberrant LR orientation of the brain and visceral organs. We also show that fgf8 is necessary for proper symmetric development of the pharyngeal skeleton. Attenuated fgf8 signaling results in consistently biased LR asymmetric development of the pharyngeal arches and craniofacial skeleton. Approximately 1/3 of zebrafish ace/fgf8 mutants are missing Kupffer's vesicle (KV), a ciliated structure similar to Hensen's node. We correlate fgf8 deficient laterality detects in the brain and viscera with the absence of KV, supporting a role for KV in proper LR patterning of these structures. Strikingly, we also correlate asymmetric craniofacial development in ace/fgf8 mutants with the presence of KV, suggesting roles for KV in lateralization of the pharyngeal skeleton when fgf8 is absent. These data provide new insights into vertebrate laterality and offer the zebrafish ace/fgf8 mutant as a novel molecular tool to investigate tissue-specific molecular laterality mechanisms. Keywords: Asymmetry Kupffer's vesicle; Craniofacial: Visceral organ; fgf8; Zebrafish

An appreciation of ontogenetic changes to the cranial base is important for understanding the evolution of modern human skull form. Using geometric morphometric techniques, this study explores midline shape variations of the basicranium and midface during human prenatal ontogeny. In particular, the analysis sets out to explore shape variations associated with endochondral ossification and to reassess shape variations previously observed on the basis of angular measures. Fifty-four formalin-preserved human fetuses were imaged using high-resolution MRI. Coordinates for 10 landmarks defining the midline basicranium and midface were acquired and areas of ossification in the midline basioccipital, basisphenoid, and presphenoid cartilages were measured as percentages of overall cranial base area. The results show shape variations with increasing fetal size that are consistent with cranial base retroflexion, anterior facial projection and dorsal facial rotation. These growth variations are centered on the midsphenoid area and are associated with disproportionate variations of sphenoid height and length. Small but significant correlations were observed between ossification of the presphenoid cartilage and components of shape that described, among other variations, sphenoid shortening. While ossification cannot be directly linked with the shape variations observed, it seems likely that bone formation plays a role in modulating the influence of other factors on the fetal cranial base. KEY WORDS basicranium; endochondral ossification; sphenoid; shape; MRI; prenatal development; angulation; evolution

Endothelin-A (ETA) is a G-protein-coupled receptor expressed in the neural crest-derived mesenchyme of the pharyngeal arches during craniofacial development. Targeted deletion of the [ET.sub.A] receptor or its ligand endothelin-1 (ET-1) causes cleft palate and hypoplasia of the mandible, otic cup, and tympanic ring. Previously we showed that G[[alpha].sub.q]/G[[alpha].sub.11]-null mice die around E 11.0, whereas G[[alpha].sub.q.sup.(-/-)] G[[alpha].sub.11.sup.(+/-)] mice survive to birth with hypomorphic phenotypes similar to, but less severe than, ETA or ET-1-null mice. To determine whether ET-1 signaling is transduced by G[[alpha].sub.q]/G[[alpha].sub.11] proteins, we examined the expression patterns of several ET-1 dependent and independent transcription factors in G[alpha].sub.q]/G[[alpha].sub.11]-deficient embryos. Expression of genes encoding the ET-1-dependent transcription factors D1x3, D1x6, dHAND, and eHAND was specifically downregulated in the pharyngeal arches of G[[alpha].sub.q]/G[alpha].sub.11]-deficient mice. In contrast, pharyngeal arch expression of the homeobox gene Msx1, which is not regulated by ET-1 signaling, was maintained in these embryos. We conclude that the G[[alpha].sub.q] and G[[alpha].sub.11] proteins serve as the intracellular mediators of ET-1 signaling in the pharyngeal arch mesenchyme. Keywords: G-protein; Neural crest; Pharyngeal arches; Endothelin; G[[alpha].sub.q]/G[[alpha].sub.11]; D1x3; D1x6; dHAND/HAND2; eHAND/HAND1; Craniofacial development

Craniofacial remains (the most abundant identifiable remains in the fossil record) potentially offer important information about body size dimorphism in extinct species. This study evaluates the scaling relationships between body mass dimorphism and different measures of craniofacial dimorphism, evaluating taxonomic differences in the magnitude and scaling of craniofacial dimorphism across higher taxonomic groups. Data on 40 dimensions from 129 primate species and subspecies demonstrate that few dimensions change proportionally with body mass dimorphism. Primates show general patterns of greater facial vs. neurocranial and orbital dimorphism, and greater dimorphism in lengths as opposed to breadths. Within any species, though, different craniofacial dimensions can yield very different reconstructions of size dimorphism. There are significant taxonomic differences in the relationships between size and craniofacial dimorphism among primate groups that can have a significant impact on reconstructions of body mass dimorphism. Hominoids tend to show lower degrees of facial dimorphism proportional to size dimorphism than other primates. This in turn implies that strong craniofacial dimorphism in Australopithecus africanus could imply very strong body size dimorphism, conflicting with the relatively modest size dimorphism inferred from postcrania. Different methods of estimating the magnitude of size dimorphism from craniofacial measurements yield similar results, and yield comparatively low percent prediction errors for a number of dimensions. However, confidence intervals for most estimates are so large as to render most estimates highly tentative. Am J Phys Anthropol 120: 38-60, 2003. KEY WORDS sexual dimorphism; primates; hominids; Australopithecus africanus; skull; mandible; allometry

Neotoma fuscipes, the dusky-footed wood rat, is a morphologically diverse taxon with recognized intraspecific subdivisions that are based on both quantitative and qualitative morphology. Although there is substantial morphological variation within this taxon, intergradation among the various forms has been observed by previous workers. A recent survey of mitochondrial DNA revealed a high degree of molecular divergence within the taxon. Here, morphological, mitochondrial sequence, and nuclear microsatellite data are examined in a contact zone between 2 reciprocally monophyletic mitochondrial clades. On the basis of concordance of qualitative cranial, glans penes, and molecular characters, the 2 units appear to be genetically isolated from one another, leading to the elevation of N. macrotis to a species separate from N. fuscipes. Key words: contact zone, cranial morphology, glans penes, microsatellites, mitochondrial DNA, Neotoma, wood rats

Homo erectus inhabited a wide geographic area of Asia, ranging from 40[degrees] north latitude in China to 8[degrees] south latitude in island Southeast Asia. Yet variation within Asian H. erectus and its relation to ecological and temporal parameters have been little studied. I synthesize the revised radiometric chronologies for hominid sites in Asia and their relation to new oxygen isotope curves (proxies for climatic fluctuations and landbridge connections). These data suggest substantial opportunities in the later Pleistocene for both regional isolation and gene flow between hominids in mainland and Southeast Asia. They also suggest that the most northerly located Chinese sites (Zhoukoudian and Nanjing) may have been occupied during sequential, interglacial periods. Probably reflecting these periods of isolation, nonmetric features and principal components analysis (PCA) of calvarial shape suggest regional differentiation between northern Asian and Southeast Asian H. erectus. The most recent Southeast Asian fossils (e.g., Ngandong) conform to the Southeast Asian pattern. Except perhaps in brain size, there is no evidence that the temporally intermediate Chinese fossils are intermediate in morphology between older and younger Indonesian fossils. In fact, northern Chinese calvaria are easier to exclude from the larger Asian H. erectus hypodigm than are the Ngandong fossils. The Chinese specimens differ from the others based on their narrower occipitals and frontals for their cranial size. The Chinese sample from Zhoukoudian alone is thus not a good proxy for the morphology and variation seen within Asian H. erectus. Both the Chinese and late Indonesian samples exhibit less variation than does the early Indonesian sample; this along with their shared morphological bauplan suggests a common origin and no more than subspecific differentiation. This shared morphology, despite regional differences, was likely maintained by the increasing intensity of multiple glaciations (and longer-lasting land bridge connections) between mainland and island Southeast Asia during the last million years. KEY WORDS [sup.18]O record; H. ergaster; Indonesia; China

Craniodental form and function were evaluated in the 2 extant, parapatric species of dermopterans (Dermoptera: Cynocephalidae). The level of morphological distinction between the 2 taxa was such that were they known as fossils; most taxonomists would not contest their genus-level distinction as indicative of adaptive differentiation. In fact, these taxa exemplify the widely employed but implicit morphological distance-based standards used for delineating mammalian genera in the paleontological literature. Appropriate names for these 2 taxa are Cynocephalus volans for the Philippine flying lemur and Galeopterus variegatus for the heterogeneous populations of the Sundaic flying lemurs. Cynocephalus probably has a hypertrophied version of the ancestral cynocephalid molar complex and modified incisor and canine morphology. The hypertrophied metaconules of cynocephalids occlude with an expanded paracristid and a cusplike shelf, the distocuspid. Cynocephalus also has a broader rostrum, a greater degree of postorbital constriction, and enhanced ectocranial ridges associated with a more robust masticatory musculature than Galeopterus. Cynocephalus appears adapted to a diet that requires a greater degree of shearing by the anterior dentition and crushing by the molariform dentition. These anterior shearing teeth (I3, C1, P3, c1, p3) are larger and more bladelike than those of Galeopterus, and the bite force is more anteriorly directed. Angle of the mandible is ventrally expanded in Cynocephalus, facilitating enhanced chewing force for the postcanine dentition while maintaining orientation of the temporalis muscle. Dwarfed forms of Galeopterus are found on many of the smaller islands of the Sunda Shelf and in central Laos. They are not morphologically distinguishable from larger members of this species, other than in size, and do not warrant specific distinction. However, it may be desirable to designate 4 subspecies of G. variegatus: G. v. variegatus from Java, G. v. temminckii from Sumatra, G. v. borneanus from Borneo, and G. v. peninsulae from the Malay Peninsula and mainland Southeast Asia. Separate species rank for each of the dwarfed populations should not be recognized. Phylogenetic relationships of Dermoptera are discussed in light of the morphological differences of the 2 genera. Key words: Colugo, Cynocephalidae, Cynocephalus volans, flying lemur, Galeopterus variegatus, kagwang, Microsyopidae, Mixodectidae, Plagiomenidae

Craniofacial characteristics of specimens from the mid-19th century and the 1970s were examined to determine changes in morphology. Results indicate vault height increase and lengthening and narrowing of face.

The anterior placement of the foramen magnum is often used to indicate bipedalism and therefore to distinguish hominid from nonhominid fossils. Often, only fragmentary cranial remains are found, and the placement of the foramen magnum must be determined by its relationship to another landmark. The purpose of this study was to test if hominid crania could be distinguished from nonhominid crania based on the relationship between the foramen magnum and the carotid foramina, and therefore to determine if the carotid foramina can be used to determine the anteriorness of the foramen magnum. The samples consisted of 16 modern human crania and 19 modern chimpanzee (Pan troglodytes) crania. Linear measurements were taken of (1) the distance from the anterior border of the foramen magnum to a chord connecting the carotid foramina and (2) total cranial length. An index of the distance of the foramen magnum from the bicarotid chord as a proportion of total cranial length was calculated to control for differences due to body size. Results indicate that on average, human crania can be distinguished from chimpanzee crania by using either (1) the distance of the foramen magnum from the bicarotid chord as a linear measurement or (2) this linear measurement as a proportion of total cranial length. Both measures are significantly smaller in the human sample; however, there was considerable overlap between species, indicating that the distance of the foramen magnum from the bicarotid chord is not a certain indicator for individual specimens. Am J Phys Anthropol 110:467-471, 1999. KEY WORDS: Australopithecus ramidus; Ardipithecus; Pan; cranium; interspecific variation

Anatomical landmarks are defined as biologically meaningful loci that can be unambiguously defined and repeatedly located with a high degree of accuracy and precision. The neurocranial surface is characteristically void of such loci. We define a new class of landmarks, termed fuzzy landmarks, that will allow us to represent the form of the neurocranium. A fuzzy landmark represents the position of a biological structure that is precisely delineated, but occupies an area that is larger than a single point in the observer's reference system. In this study, we present a test case in which the cranial bosses are evaluated as fuzzy landmarks. Five fuzzy landmarks (the cranial bosses) and three traditional landmarks were placed repeatedly by a single observer on three-dimensional (3D) computed tomography (CT) surface reconstructions of pediatric dry skulls and skulls of pediatric patients, and directly on four of the same dry skulls using a 3Space digitizer. Thirty landmark digitizing trials from CT scans show an average error of 1.15 mm local to each fuzzy landmark, while the average error for the last ten trials was 0.75 mm, suggesting a learning curve. Data collected with the 3Space digitizer was comparable. Measurement error of fuzzy landmarks is larger than that of traditional landmarks, but is acceptable, especially since fuzzy landmarks allow inclusion of areas that would otherwise go unsampled. The information obtained is valuable in growth studies, clinical evaluation, and volume measurements. Our method of fuzzy landmarking is not limited to cranial bosses, and can be applied to any other anatomical features with fuzzy boundaries. KEY WORDS measurement error; coordinate data; craniofacial skeleton

A sexual dimorphism more marked than in living humans has been claimed for European Middle Pleistocene humans, Neandertals and prehistoric modern humans. In this paper, body size and cranial capacity variation are studied in the Sima de los Huesos Middle Pleistocene sample. This is the largest sample of non-modern humans found to date from one single site, and with all skeletal elements represented. Since the techniques available to estimate the degree of sexual dimorphism in small palaeontological samples are all unsatisfactory, we have used the bootstraping method to asses the magnitude of the variation in the Sima de los Huesos sample compared to modern human intrapopulational variation. We analyze size variation without attempting to sex the specimens a priori. Anatomical regions investigated are scapular glenoid fossa; acetabulum; humeral proximal and distal epiphyses; ulnar proximal epiphysis; radial neck; proximal femur; humeral, femoral, ulnar and tibial shaft; lumbosacral joint; patella; calcaneum; and talar trochlea. In the Sima de los Huesos sample only the humeral midshaft perimeter shows an unusual high variation (only when it is expressed by the maximum ratio, not by the coefficient of variation). In spite of that the cranial capacity range at Sima de los Huesos almost spans the rest of the European and African Middle Pleistocene range. The maximum ratio is in the central part of the distribution of modern human samples. Thus, the hypothesis of a greater sexual dimorphism in Middle Pleistocene populations than in modern populations is not supported by either cranial or postcranial evidence from Sima de los Huesos. KEY WORDS body size; cranial capacity; sexual dimorphism; bootstrapping

Studies on dental arch form, craniofacial morphology and bite force of Fijians were conducted in 1994 and 1995. The results of these studies were compared with Japanese populations. The study indicated that masticatory muscles and craniofacial morphologies were better integrated in Fijians than in Japanese.

Maya adult crania from the site of Lamanai, Belize provide a retrospective means of examining growth processes in the cranial vault. The Lamanai population practiced fronto-occipital deformation which is found to be significantly associated with premature sagittal synostosis and wormian bones of the lambdoidal suture. The undeformed members of the population also exhibit an abnormally high frequency of sagittal synostosis, but a significantly lower frequency than the deformed sample. It is suggested that the deforming apparatus creates tensile forces on the sagittal suture during the peak period of growth of the parietals, and that these forces might induce an adaptive response important in producing premature sagittal synostosis. The undeformed sample may have an increased congenital risk of sagittal synostosis created by their natural brachycephalic morphology in utero. The frequency patterning of wormian bones suggests a mixture of genetic and environmental causes in which tensile forces may also play a role. KEY WORDS Cranial deformation, Maya, Sagittal synostosis, Brachycephaly, Wormian bones, Fronto-occipital

The specimen is identified as the partial cranium of a nodosaurid ankylosaur (Ornithischia: Thyreophora) on the basis of the presence of bone which is fused to the dorsal surface of the skull and has secondarily closed the upper temporal fenestrae. The only unequivocally nodosaurid material recovered from the Isle of Wight to date comes from Wealden facies, and has been referred to the genus Polacanthus; it is considered highly probable that this new skull is referable to the same genus. Despite having undergone abrasion, through post-emergence water-rolling, the skull and cranial walls have proved to be relatively informative of the general anatomy of the braincase and the neural and vascular anatomy of this part of the head. The anatomy of the braincase of most ankylosaurs (with the notable exception of the juvenile specimens of the ankylosaurid Pinacosaurus) is surprisingly poorly known, despite the relative abundance of cranial material in North American and Asian collections. The cranial neural and vascular anatomy is well shown in this specimen and enables the first detailed description of nodosaurid endocranial structures. The general form of the brain can be outlined from the structure of the endocast and the principal lobes can be identified; the majority of the cranial nerves have been identified, and a significant component of the associated vascular system is also visible. In most respects the endocast shows a neural anatomy which is common to that known in most dinosaurs. When compared to their nearest relatives, the ankylosaurid ankylosaurs (Euoplocephalus), the nodosaurid endocranial cast shows a more pronounced cerebral flexure, a forebrain which is broader and more expanded dorsally, and a more prominent cerebellum (although there is no evidence for a floccular lobe); there are minor differences in the arrangement of the cranial nerves, and the dorsal portions of the vascular system are better shown. Because of erosion, the olfactory lobes of this specimen of cf. Polacanthus are not preserved, and cannot be compared to those of ankylosaurid ankylosaurs; the latter are unusual in the strong separation of the lobes (reflected in the divergent olfactory stalks); this feature may be associated with the very complex passages within the nasal region of the skull, which are lacking in the nodosaurids described to date.

Cradleboarding was practiced by numerous prehistoric and historic populations, including the Hopi. In this group, one result of cradleboarding was bilateral or asymmetric flattening of the posterior occipital. We test whether cradleboarding had significant effects on the morphology of the cranial vault, cranial base, and face. Additionally, we examine associations between direction of flattening and asymmetric craniofacial growth. A skeletal sample of Hopi from the Old Walpi site includes both nonmodified (N = 43) and modified individuals (N = 39). Three-dimensional coordinates of 53 landmarks were obtained using a diagraph. Thirty-six landmarks were used to define nine finite elements in the cranial vault, cranial base, and face. Finite element scaling was used to compare average nonmodified individuals, with averages of bilaterally, right, and left modified individuals. The significance of variation among 'treatment' groups was evaluated using a bootstrap test. Pearson product-moment correlations test the association of asymmetry with direction of modification. Hopi cradleboarding has a significant effect on growth of the cranial vault, but does not affect morphology of the cranial base or face. Bilateral flattening of the cranial vault leads to decreased length and increased width of the cranial vault. Flattening of the right or left cranial vault results in ipsilaterally decreased length and width coupled with a corresponding increased length and width on the contralateral side of the cranial vault. There is a significant correlation of size asymmetry with direction of modification in the cranial vault, but not with size or shape change in the cranial base or face. KEY WORDS Cranial growth, Finite element scaling, Hopi, Cradleboard

A study of object-related activation shows that it is positioned at the occipital lobe's lateral posterior area, just touching the motion-sensitive area MT/V5s posterior aspect, in a region termed the lateral occipital complex (LO). Despite the preferential activation to objects, LO did not seem to be involved in the final recognition process stages but as an intermediate link.

Anatomically modern hominids were first collected from Kanjera, Kenya, by L.S.B. Leakey in the 1930s. Their apparent association with an archaic fauna was quickly challenged, throwing their age into doubt. Further unpublished hominid fragments were collected in 1974, 1975, 1981, and 1987. We review the context and morphology of the entire hominid sample. A minimum number of five individuals is represented by both cranial and postcranial elements. Several individuals have thickened cranial vaults, a characteristic originally thought to reflect their great antiquity. Vault thickening resulted from diploic expansion and may have been a response to acquired or inherited anemia. The entire hominid sample postdates the Kanjera Formation, deposited from the early into the middle Pleistocene. Most of the sample was derived from the black cotton soil capping the stratigraphic column. The morphology and context of the Kanjera hominids is consistent with human skeletal remains from nearby Holocene sites. Hominid 3 was probably an intrusive burial into an early Pleistocene bed.

A new automatic target recognition algorithm has been developed to extract craniofacial landmarks from lateral skull x-rays (cephalograms). The locations of these landmarks are used by orthodontists in what is referred to as a cephalometric evaluation. The evaluation assists in the diagnosis of anomalies and in the monitoring of treatments. The algorithm is based on gray-scale mathematical morphology. A statistical approach to training was used to overcome subtle differences in skeletal topographies. Decomposition was used to desensitize the algorithm to size differences. A system was trained to locate 20 landmarks. Tests on 40 x-rays showed an 85% recognition rate on average.

The results of a detailed morphological analysis of the skull attributed to Mozart are presented which refute a recent claim that the skull as well as several of Mozart's portraits show indications of uncomplicated trigonocephaly. These indications according to the present analysis are within the limits of normal variation and derive from retention of part of the long arm of the anterior fontanelle.

Reexamination of the immature Upper Pleistocene hominid maxilla from Mugharet el-'Aliya (Tangier), Morocco is undertaken in light of new evidence on the growth and development of Upper Pleistocene hominids. Metric and qualitative comparisons were made with 17 immature Upper Pleistocene maxillae, and with a recent Homo sapiens sapiens sample. No unambiguous criteria for aligning the maxilla with Neandertals were found, although one character, the degree of maxillary flexion on the zygoma, strongly suggests that this child could be a representative of H. s. sapiens. The probable lack of a canine fossa in Mugharet el-'Aliya 1, the primary criterion used previously to align it with Neandertals, cannot be accurately extrapolated to its adult form from this juvenile. The present evidence suggests that it is inappropriate to refer to this fossil as 'Neandertal-like' or as a North African 'neandertaloid.' Thus, the Tangier maxilla should not be cited as evidence for the presence of Neandertal facial features in North Africa during the Upper Pleistocene.

In this paper we examine the results of an intraobserver measurement error study involving 49 craniofacial variables that ranged in size from less than 1 cm to approximately 20 cm. Repeat measurements were taken on 10 male and 10 female adult subjects (19-59 years old). Our focus is on the relationship between measurement size and measurement error across the 49 variables. We found that the size of the variable showed no relationship with the magnitude of the error as measured by the technical error of measurement. When the error was expressed as a coefficient of relative variation (Malina et al.: Vital and Health Statistics, Series 11, No. 23. Washington, DC: US Department of Health and Human Services, 1973), this quantity was negatively associated with the size of the measurement. Conversely, reliability (Fleiss: The Design and Analysis of Experiments. New York: John Wiley & Sons, 1986) was positively correlated with measurement size. We did not find effects of scale (Marks et al.: Am. J. Epidemiol. 130:578-587, 1989) within the individual measurements. Thus, for the range of size of the craniofacial measurements in this study, measurement size must be added to the list of factors such as ease of locating landmarks, measurement technique, and systematic bias in the application of the technique that can affect precision and reliability in anthropometry.

An analysis of First Dynasty crania from Abydos was undertaken using multiple discriminant functions. The results demonstrate greater affinity with Upper Nile Valley patterns, but also suggest change from earlier craniometric trends. Gene flow and movement of northern officials to the important southern city may explain the findings.

Cultural reshaping (artificial deformation or modification) of the neurocranial vault provides an artificially increased range of morphological variability within which the relationship between the growing neurocranium and face can be investigated. We analyze crania which have been fronto-occipitally compressed to ascertain possible morphological effects on the mandible. We collected measures of mandibular breadth, length, and height from 82 modified (N = 48) and unmodified (N = 34) crania from a Peruvian Ancon series. Angle classification was also scored in order to investigate whether or not occlusal relationships were affected by neurocranial reshaping. Only intercondylar distance (posterior mandibular breadth) exhibited significant differences between unmodified and modified groups, though this difference was relatively small compared with vault deformation. The modified crania had a higher frequency of normal occlusion (Class I) than the unmodified crania. Increased intercondylar breadth in modified skulls is due to a cascade of effects which begin with a direct effect of the fronto-occipital deforming device on neurocranial shape (increased neurocranial width). The increase in mandibular breadth may be a compensatory response to increased cranial base breadth and maintains articulation between the cranial base and mandible. The increased posterior breadth, coupled with a slight decrease in mandibular depth, may contribute to the change in occlusal relationships suggested for this sample.

Previously known and recently discovered hominid fossils in China exhibit a mosaic of regionally restricted and extra-regional morphological traits which evolve in the general direction of modern humans. Specifically East Asian features are concentrated in the midfacial region, while other craniofacial regions (upper face, lower face, occipital, and some basicranial features) show a gradual and general divergence in the direction of all extant human groups. Some extra-regional traits suddenly appear in the Middle and Late Pleistocene, suggesting a period of increased and intensified long range gene flow. Although difficult to define, Homo erectus exhibits a few autapomorphic and synapomorphic features (with Archaics and Neanderthals) which do not exclude it from human ancestry. The strict application of cladistic method and theory has supported the interpretation that Homo erectus was not ancestral to modern humans. An alternative chronophenetic assessment of the fossil Asians does not support a Replacement Model, but instead supports a variant of the Regional Continuity Model, an Assimilation Model, as the most parsimonious means of understanding the origins of modern humans in China and other parts of the Old World.

Endocranial volume (ECV) variability as measured by the coefficient of variation (CV) has been important in supporting the view that more than one species is represented in Homo habilis. Supporters of this view used a CV of 10 as a standard to determine that 1) the H. habilis CV of 12.7 indicates multiple species and 2) there is a low probability of H. habilis specimens KNM-ER 1470 and KNM-ER 1813 being members of the same taxon. This study examines published data for ECVs of fossil and extant hominoids to determine whether CV yields any information regarding species number in H. habilis. Results indicate that there is no empirical basis for using a CV of 10 as a standard to detect multiple species in H. habilis. Also, geography, time, sample choice, sex ratio, and measurement technique are complicating factors that must be considered when interpreting CVs for fossil samples. Additionally, the broad 95% statistical confidence limits (5.1-20.3) indicate that the CV estimate of 12.7 for H. habilis is not sufficiently reliable to allow biologically meaningful interpretation. However, if the CV for H. habilis is actually 12.7, it still falls within the range of variation for single species of modern hominoids. The evidence from ECV variability does not support the argument for multiple species in H. habilis.

Historical sources and archaeological data predict significant population variability in mid-Holocene northern Africa. Multivariate analyses of crania demonstrate wide variation but also suggest an indigenous craniometric pattern common to both late dynastic northern Egypt and the coastal Maghreb region. Both tropical African and European metric phenotypes, as well intermediate patterns, are found in mid-Holocene Maghreb sites. Early southern predynastic Egyptian crania show tropical African affinities, displaying craniometric trends that differ notably from the coastal northern African pattern. The various craniofacial patterns discernible in northern Africa are attributable to the agents of microevolution and migration.

The masticatory system consists of teeth, temporomandibular joints, and the supporting craniofacial skeleton. The form and function of each of these components of the system can be understood only within the overall context of the system. In a series of studies, the complex relationships between tooth wear and temporomandibular joint morphology and pathology were considered in samples consisting of a total of 58 male and 54 female crania from two Australian Aboriginal populations. The extent and buccolingual direction of tooth wear were assessed using established techniques. Both metric and nonmetric descriptions of temporomandibular joint morphology and pathology were developed. Significant differences in patterns of tooth wear and in the frequencies of various temporomandibular joint changes were evident between sexes and between populations. Furthermore, significant correlations between a number of tooth and joint variables were also evident. In addition, there was clear evidence of relationships between both tooth wear and temporomandibular joint changes and craniofacial morphology. The results of this study provide additional evidence of the complex relationships between the form and function of the masticatory system.

Widely dispersed throughout the Pacific, Polynesians are a biologically distinctive people in form and size of both body and head. Large-bodied and well-muscled, their body phenotype is suited to life in a thermolabile oceanic environment. Their craniofacial skeleton is large and robust, with mandibular size and form (the 'rocker' mandible) being especially characteristic. In this paper the Polynesian variants of body form, and of facial size (including dentition) and form, are interpreted from a functional perspective.

Longitudinal studies of aboriginal children over a 20-year period have drawn attention to the wide variation in morphological features of the dentition and the way in which occlusal relationships develop. This paper summarizes some important determinants of optimal occlusal development, namely, tooth size relationships within and between dentitions, the patterns of alveolar growth, and tooth migrations during the transition from primary to permanent teeth and the nature of growth changes in the dental arches. Dental occlusion constantly changes throughout life in response to changing functional requirements. Observations limited to cross-sectional material provide an incomplete, and sometimes misleading, concept of dental occlusion and masticatory function.

Twenty weanling 6-month-old male squirrel monkeys were allotted to the following treatments: 1) first control animals were killed at weaning; 2) second control animals were killed when 24 months old; and 3) malnourished animals were fed on a low-protein diet and killed at age 24 months. Lateral and vertical teleradiographies were taken. Growth of the neurocranial and splanchnocranial components were measured by volumetric (size estimators) and morphometric (shape estimators) indices. All facial components grew. The neurocranial components showed a heterogeneous behavior: The anteroneural component remained stable, and the increase of the midneural component was compensated by a decrease in the posteroneural component. Malnutrition affected the growths of 1) the craniofacial complex, 2) the splanchnocranium, and 3) the respiratory and midneural components. Growth influenced skull shape through 1) increases of the splanchnocranium and the midneural component relative to the neurocranium; 2) decreases of the masticatory and optic components relative to the splanchnocranium, and 3) decreases of the anteroneural and posteroneural components relative to the neurocranium. Malnutrition influenced skull shape through the relationship between the anteroneural component and the neurocranium. These results confirmed the existence of functional interrelationships among the cranial components. A new approach to craniological studies is suggested.

Endocranial Features of Australopithecus africanus Revealed by 2- and 3-D Computed Tomography BRAIN SIZE IS AN IMPORTANT BIOlogical parameter and its measurement should be s accurate as possible, particularly in [...]

Recently discovered crania of Australopithecus africanus from Sterkfontein Member 4 and Makapansgat enlarge the size range of the species and encourage a reappraisal of both the degree and pattern of sexual dimorphism. Resampling methodology (bootstrapping) is used here to establish that A. africanus has a greater craniofacial size range than chimpanzees or modern humans, a range which is best attributed to a moderately high degree of sexual dimorphism. Compared to other fossil hominins, this variation is similar to that of Homo habilis (sensu lato) but less than that of A. boisei. The finding of moderately high dimorphism is corroborated by a CV-based estimate and ratios between those specimens considered to be male and those considered to be female. Inferences about the pattern of craniofacial dimorphism in the A. africanus face currently rely on the relationship of morphology and size. Larger specimens, particularly Stw 505, show prominent superciliary eminences and glabellar regions, but in features related in part to canine size, such as the curvature of the infraorbital surface, large and small specimens of A. africanus are similar. In this respect, the pattern resembles that of modern humans more so than chimpanzees or lowland gorillas. A. africanus may also show novel patterns of sexual dimorphism when compared to extant hominines, such as in the form of the anterior pillar. However, males of the species do not exhibit characteristics of more derived hominins, such as A. robustus. KEY WORDS hominids; hominoids; variation; Sterkfontein; Makapansgat; systematics

Craniofacial development occurs through the outgrowth and fusion of neural-crest-derived prominences. Failure of the prominences to grow together properly can result in a number of facial deformities, of which cleft palate is the most common. Animal models have been used to investigate this problem, but many have severe defects which are complicated to study. A mutation known as cleft primary palate (cpp) has been discovered in the chicken that causes complete failure of primary palate formation and consequent bilateral cleft lip with a truncated upper beak. A series of grafting and tissue recombination experiments shows that the mutation affects the frontonasal mass (25 of 25). All other prominences in the embryonic face grow normally in a chick limb graft system (15 of 15). The growth of mutant frontonasal mass mesenchyme is restored by recombination with wild-type epithelium (30 of 41), implying that the mutation primarily affects the frontonasal mass epithelium. In situ hybridization shows that the mutant phenotype correlates with alterations in the expression of AP-2, Fgf-8, and Msx-1, known face patterning genes. These results indicate that the cpp mutation is associated with a defect in epithelial-mesenchymal molecular signaling in the chick fronto nasal mass, leading to a failure of this prominence to grow along a proximodistal axis and subsequent cleft palate.

Cranial placodes are focal regions of thickened ectoderm in the head of vertebrate embryos that give rise to a wide variety of cell types, including elements of the paired sense organs and neurons in cranial sensory ganglia. They are essential for the formation of much of the cranial sensory nervous system. Although relatively neglected today, interest in placodes has recently been reawakened with the isolation of molecular markers for different stages in their development. This has enabled a more finely tuned approach to the understanding of placode induction and development and in some cases has resulted in the isolation of inducing molecules for particular placodes. Both morphological and molecular data support the existence of a preplacodal domain within the cranial neural plate border region. Nonetheless, multiple tissues and molecules (where known) are involved in placode induction, and each individual placode is induced at different times by a different combination of these tissues, consistent with their diverse fates. Spatiotemporal changes in competence are also important in placode induction. Here, we have tried to provide a comprehensive review that synthesises the highlights of a century of classical experimental research, together with more modern evidence for the tissues and molecules involved in the induction of each placode. [C] 2001 Academic Press Key Words: placode; olfactory; hyophyseal; adenohypophysis; lens; trigeminal; lateral line; otic; epibranchial; zebrafish; Xenopus; axolotl; chick; mouse.

The limited morphometric work on early American crania to date has treated them as a single, temporally defined group. This paper addresses the question of whether there is significant variability among ancient American crania. A sample of 11 crania (Spirit Cave, Wizards Beach, Browns Valley, Pelican Rapids, Prospect, Wet Gravel male, Wet Gravel female, Medicine Crow, Turin, Lime Creek, and Swanson Lake) dating from the early to mid Holocene was available. Some have recent accelerator mass spectrometry (AMS) dates, while others are dated geologically or archaeologically. All are in excess of 4500 BP, and most are 7000 BP or older. Measurements follow the definitions of Howells [(1973) Cranial variation in man, Cambridge: Harvard University). Some crania are incomplete, but 22 measurements were common to all fossils. Cranial variation was examined by calculating the Mahalanobis distance between each pair of fossils, using a pooled within sample covariance matrix estimated from the data of Howells. The distance relationships among crania suggest the presence of at least three distinct groups: 1) a middle Archaic Plains group (Turin and Medicine Crow), 2) a Paleo/Early Archaic Great Lakes/Plains group (Browns Valley, Pelican Rapids, Lime Creek), and 3) a spatially and temporally heterogeneous group that includes the Great Basin/Pacific Coast (Spirit Cave, Wizards Beach, Prospect) and Nebraska (Wet Gravel specimens and Swanson Lake). These crania were also compared to Howells' worldwide recent sample, which was expanded by including six additional American Indian samples. None of the fossils, except for the Wet Gravel male, shows any particular affinity to recent Native Americans; their greatest similarities are with Europe, Polynesia, or East Asia. Several crania would be atypical in any recent population for which we have data. Browns Valley, Pelican Rapids, and Lime Creek are the most distinctive. They provide evidence for the presence of an early population that bears no similarity to the morphometric pattern of recent American Indians or even to crania of comparable date in other regions of the continent. The heterogeneity among early American crania makes it inadvisable to pool them for purposes of morphometric analysis. Whether this heterogeneity results from different early migrations or one highly differentiated population cannot be established from our data. Our results are inconsistent with hypotheses of an ancestor-descendent relationship between early and late Holocene American populations. They suggest that the pattern of cranial variation is of recent origin, at least in the Plains region. Am J Phys Anthropol 114:146-155, 2001. [C] 2001 Wiley-Liss, Inc. KEY WORDS Paleoamericans; cranial morphometrics; New World

In a previous study about volume comparisons of the cerebellar complex in some hominoid species (1997), progressive development of only the lateral zone group of nuclei was found in the human cerebellar complex. This development was considered to be related not to bipedalism, but to versatile and coordinated finger movement, evolving after bipedalism was established. It was also considered a prerequisite for the evolution of human language. The lateral zone groups of nuclei are represented by the dentate nucleus. Therefore, the present study reports the development of the dentate nucleus in humans in comparison with that in some great apes. One finding is that the average value of ratios for nucleus size of the ventral half (v) to the dorsal half (d) (v/d) was found to be 2.11 in humans, while it was 1.64 in great apes. This finding shows that the greater part of progressive development of the dentate nucleus in humans is due to the development of its ventral half. Therefore, the fiber connection to the frontal association area from the cerebellar cortex, which is involved in the performance of higher cerebellar functions such as cognitive and language functions, would be mediated by the ventral half of the dentate nucleus. Am J Phys Anthropol 114: 163-165, 2001. [C] 2001 Wiley-Liss, Inc. KEY WORDS cerebellar dentate nucleus; proportion; ventral half; higher cerebellar function; hominoids; Stephan's collection