Analysis of the hominoid os coxae by Cartesian coordinates.

This study is based upon 48 3-dimensional coordinates taken on 4 fossil hominid and 127 extant hominoid coxal bones. The follis include Sts 14, SK 3155, MLD 7, and MLD 25. The comparative sample consists of 42 Homo sapiens, 27 Pan troglodytes, 29 Gorilla gorilla and 29 Pongo pygmaeus. The coordinates improve the metrical representation of the bone beyond what can be done with linear measurements because the shape complexity of the os coxae is so great. The coordinates are rotated and translated so that all bones are in a standard position. The coordinates are then standardized for each specimen by dividing all coordinates by the pooled standard deviation of X, Y, and Z coordinates. These data are treated to standard statistical analyses including analysis of variance, Penrose size and shape statistics, principal coordinates and components, and canonical variates analysis. The data are then further altered by using some specimen as a standard and rotating each specimen until the total squared distance between its coordinates and those of the standard are minimized. The same statistics are applied to these "best fit" data. The results show a high degree of agreement between the methods. The hominid os coxae are dundamentally different from the other hominoids and the fossil hominids share the basic hominid configuration but with some unique differences.     

Size and shape of the australopithecine pelvic bone

The recovery of several specimens allows to have a good knowledge of australopithecine pelvic bone anatomy. But despite this, differences of opinion still exist regarding locomotory interpretations. The aim of this paper is to present results of a new morphometric analysis of australopithecine pelvic bones to try to understand the reasons of this situation. It appears that australopithecines exhibit the same overall architectural pattern as extant humans, the hominid pattern, just as all African apes also exhibit the same pongid pattern. But, in this pattern, it is possible to clearly depict two subpatterns corresponding to both generaAustralopithecus andHomo. Locomotory interpretations depend on the fact that some studies emphasize traits related to the hominid pattern (concluding then on modern bipedalism) and others focus on trains characterizing australopithecine sub-pattern (concluding then on non-modern bipedalism).     

Assessing endocranial variations in great apes and humans using 3D data from virtual endocasts

Modern humans are characterized by their large, complex, and specialized brain. Human brain evolution can be addressed through direct evidence provided by fossil hominid endocasts (i.e. paleoneurology), or through indirect evidence of extant species comparative neurology. Here we use the second approach, providing an extant comparative framework for hominid paleoneurological studies. We explore endocranial size and shape differences among great apes and humans, as well as between sexes. We virtually extracted 72 endocasts, sampling all extant great ape species and modern humans, and digitized 37 landmarks on each for 3D generalized Procrustes analysis. All species can be differentiated by their endocranial shape. Among great apes, endocranial shapes vary from short (orangutans) to long (gorillas), perhaps in relation to different facial orientations. Endocranial shape differences among African apes are partly allometric. Major endocranial traits distinguishing humans from great apes are endocranial globularity, reflecting neurological reorganization, and features linked to structural responses to posture and bipedal locomotion. Human endocasts are also characterized by posterior location of foramina rotunda relative to optic canals, which could be correlated to lesser subnasal prognathism compared to living great apes. Species with larger brains (gorillas and humans) display greater sexual dimorphism in endocranial size, while sexual dimorphism in endocranial shape is restricted to gorillas, differences between males and females being at least partly due to allometry. Our study of endocranial variations in extant great apes and humans provides a new comparative dataset for studies of fossil hominid endocasts.     

Long bones of the primate upper limb: Monomorphic or dimorphic?

An important debate has been taking place during the last few years concerningAustralopithecus afarensis: can the Hadar sample be ascribed to one highly dimorphic species or should it be separated into two distinct taxa? A similar problem occurs with the Middle Miocene cercopithecoids from East Africa: does this material belong to one dimorphic group or can we recognize two different taxa? The study of the long bones of the upper limb of many extant primates suggests that the extremities in different taxa are very distinctive but that within taxa the joints are weakly or are not morphologically dimorphic although they can be markedly size dimorphic. The main shape and size differences which can be ascribed to sexual dimorphism occur in the shafts of the long bones. Examinations have been made inHomo, Pan, Gorilla, Pongo, Hylobates, Alouatta, Cebus, Saimiri, Ateles, Nasalis, Presbytis and some Cercopithecinae. It appears, then, that the extremities of the bones are shape monomorphic. If the same relationships occurred in the fossil record, then the differences observed in the hominid fossil elbow joints at Hadar suggest that at least two different taxa are represented in the collection. In addition, among the cercopithecoid material assigned toVictoriapithecus from Maboko and Nyakach in East Africa, we recognize two distinct elbow morphologies indicating that two different taxa occur in the localities.     

Ontogeny and phylogeny of the pelvis in Gorilla, Pongo, Pan, Australopithecus and Homo

To examine the evolutionary differences between hominoid locomotor systems, a number of observations concerning the growth of the pelvis among the great apes as compared to modern and fossil hominids are reported. We are interested in the size and shape of the coxal bones at different developmental stages across species that may elucidate the relationship between ontogeny and phylogeny (i.e., heterochrony) in the hominoid pelvis. Our hypotheses are: (1) do rates of absolute growth differ?, (2) do rates of relative growth differ?, and (3) does heterochrony explain these differences? Bivariate and multivariate analyses of pelvic dimensions demonstrate both the diversity of species-specific ontogenetic patterns among hominoids, and an unequivocal separation of hominids and the great apes. Heterochrony alone fails to account for the ontogenetic differences between hominids and the great apes. Compared to recent Homo,Australopithecus can be described as 'hyper-human' from the relative size of the ischium, and short but broad ilium. Australopithecus afarensis differs from Australopithecus africanus by its relatively long pubis. In multivariate analyses of ilium shape, the most complete coxal bone attributed to Homo erectus, KNM-ER 3228, falls within the range of juvenile and adult Australopithecus, whereas Broken Hill falls within the range of modern Homo, suggesting that the modern human ilium shape arose rather recently. Among the great apes, patterns of pelvic ontogeny do not exclusively separate the African apes from Pongo.     

Inferring hominoid and early hominid phylogeny using craniodental characters: the role of fossil taxa

Recent discoveries of new fossil hominid species have been accompanied by several phylogenetic hypotheses. All of these hypotheses are based on a consideration of hominid craniodental morphology. However, Collard and Wood (2000) suggested that cladograms derived from craniodental data are inconsistent with the prevailing hypothesis of ape phylogeny based on molecular data. The implication of their study is that craniodental characters are unreliable indicators of phylogeny in hominoids and fossil hominids but, notably, their analysis did not include extinct species. We report here on a cladistic analysis designed to test whether the inclusion of fossil taxa affects the ability of morphological characters to recover the molecular ape phylogeny. In the process of doing so, the study tests both Collard and Wood's (2000) hypothesis of character reliability, and the several recently proposed hypotheses of early hominid phylogeny. One hundred and ninety-eight craniodental characters were examined, including 109 traits that traditionally have been of interest in prior studies of hominoid and early hominid phylogeny, and 89 craniometric traits that represent size-corrected linear dimensions measured between standard cranial landmarks. The characters were partitioned into two data sets. One set contained all of the characters, and the other omitted the craniometric characters. Six parsimony analyses were performed; each data set was analyzed three times, once using an ingroup that consisted only of extant hominoids, a second time using an ingroup of extant hominoids and extinct early hominids, and a third time excluding Kenyanthropus platyops. Results suggest that the inclusion of fossil taxa can play a significant role in phylogenetic analysis. Analyses that examined only extant taxa produced most parsimonious cladograms that were inconsistent with the ape molecular tree. In contrast, analyses that included fossil hominids were consistent with that tree. This consistency refutes the basis for the hypothesis that craniodental characters are unreliable for reconstructing phylogenetic relationships. Regarding early hominids, the relationships of Sahelanthropus tchadensis and Ardipithecus ramidus were relatively unstable. However, there is tentative support for the hypotheses that S. tchadensis is the sister taxon of all other hominids. There is support for the hypothesis that A. anamensis is the sister taxon of all hominids except S. tchadensis and Ar. ramidus. There is no compelling support for the hypothesis that Kenyanthropus platyops shares especially close affinities with Homo rudolfensis. Rather, K. platyops is nested within the Homo + Paranthropus + Australopithecus africanus clade. If K. platyops is a valid species, these relationships suggest that Homo and Paranthropus are likely to have diverged from other hominids much earlier than previously supposed. There is no support for the hypothesis that A. garhi is either the sister taxon or direct ancestor of the genus Homo. Phylogenetic relationships indicate that Australopithecus is paraphyletic. Thus, A. anamensis and A. garhi should be allocated to new genera.     

Effects of size and locomotor adaptations on the hominid pelvis: evaluation of australopithecine bipedality with a new multivariate method

Three pelves and eight innominate bones belonging to the fossil species, Australopithecus africanus, Australopithecus robustus, Homo erectus, and Homo sapiens, have been studied biometrically and compared with those of recent humans and apes. A new method of logarithmic factorial analysis suppresses both the size effects and the size reference on pelvic proportions. In combination with principal component analysis it allows specializations to be dissociated from allometrical variations. Some morphological differences on the hominid pelvis prove to be mainly allometric. However, the pelvic morphology of australopithecines is clearly differentiated from that of the genus Homo (including H. erectus, OH 28, KNMER 3227). A. africanus (Sts 14, MLD 7, AL 288) is nearer the humans than is A. robustus (SK 50, SK 3155), which appears to be more specialized in the australopithecine lineage. The pelvic morphology of A. africanus, as integrated with the articular pelvic-femoral link, appears to be biometrically equivalent to that of humans.     

A 3D quantitative comparison of trapezium and trapezoid relative articular and nonarticular surface areas in modern humans and great apes

The structure and functions of the modern human hand are critical components of what distinguishes Homo sapiens from the great apes (Gorilla, Pan, and Pongo). In this study, attention is focused on the trapezium and trapezoid, the two most lateral bones of the distal carpal row, in the four extant hominid genera, representing the first time they have been quantified and analyzed together as a morphological-functional complex. Our objective is to quantify the relative articular and nonarticular surface areas of these two bones and to test whether modern humans exhibit significant shape differences from the great apes, as predicted by previous qualitative analyses and the functional demands of differing manipulative and locomotor strategies. Modern humans were predicted to show larger relative first metacarpal and scaphoid surfaces on the trapezium because of the regular recruitment of the thumb during manipulative behaviors; alternatively, great apes were predicted to show larger relative second metacarpal and scaphoid surfaces on the trapezoid because of the functional demands on the hands during locomotor behaviors. Modern humans were also expected to exhibit larger relative mutual joint surfaces between the trapezoid and adjacent carpals than do the great apes because of assumed transverse loads generated by the functional demands of the modern human power grip. Using 3D bone models acquired through laser digitizing, the relative articular and nonarticular areas on each bone are quantified and compared. Multivariate analyses of these data clearly distinguish modern humans from the great apes. In total, the observed differences between modern humans and the great apes support morphological predictions based on the fact that this region of the human wrist is no longer involved in weight-bearing during locomotor behavior and is instead recruited solely for manipulative behaviors. The results provide the beginnings of a 3D comparative standard against which further extant and fossil primate wrist bones can be compared within the contexts of manipulative and locomotor behaviors.     

Perikymata spacing and distribution on hominid anterior teeth

We documented the spacing and distribution of perikymata on the buccal enamel surface of fossil hominin anterior teeth with reference to a sample of modern human and modern great ape teeth. A sample of 27 anterior teeth attributed to Australopithecus (5 to A. afarensis, 22 to A. africanus) and of 33 attributed to Paranthropus (6 to P. boisei, and 27 to P. robustus) were replicated and sputter-coated with gold to enable reflected light microscopy of their surface topography. Anterior teeth were then divided into 10 equal divisions of buccal crown height. The total perikymata count in each division of crown height was recorded using a binocular microscope fitted with a vernier micrometer eyepiece. Then the mean number of perikymata per millimeter was calculated for each division. Similar comparative data for a modern sample of 115 unworn human anterior teeth and 30 African great ape anterior teeth were collected from ground sections. Perikymata counts in each taxon (together with either known or presumed periodicities of perikymata) were then used to estimate enamel formation times in each division of crown height, for all anterior tooth types combined. The distributions of these estimates of time taken to form each division of crown height follow the same trends as the actual perikymata counts and differ between taxa in the same basic way. The distinction between modern African great apes and fossil hominins is particularly clear. Finally, we calculated crown formation times for each anterior tooth type by summing cuspal and lateral enamel formation times. Estimates of average crown formation times in australopiths are shorter than those calculated for both modern human and African great ape anterior teeth. The data presented here provide a better basis for exploring differences in perikymata spacing and distribution among fossil hominins, and provide the first opportunity to describe four specimens attributed to Homo in this context. Preliminary data indicate that differences may exist among the species attributed to early Homo, especially between Homo ergaster and Homo rudolfensis on the one hand, and Homo habilis sensu strico on the other.     

巨猿牙齿釉质厚度及对食性适应与系统演化的意义

步氏巨猿(Gigantopithecus blacki)是更新世时期生活于我国华南地区的一种超大型猿类, 它的体态特征和演化分类倍受关注。牙齿釉质厚度在探讨灵长类食性、环境适应以及系统演化方面具有重要意义。本文利用显微CT技术构建18颗巨猿臼齿虚拟模型, 测量其釉质厚度。将巨猿釉质厚度与现代人、现生类人猿、古人类、中新世古猿及其他现生灵长类进行比较, 从牙齿釉质厚度探讨巨猿的食性适应和系统演化问题。结果发现巨猿的实测釉质厚度是目前所有已知现生和化石灵长类中最厚的, 只有傍人、南非早期人属及奥兰诺古猿三种化石灵长类与之接近; 如果考虑不同物种牙齿与身体大小的关联因素, 相对釉质厚度指数显示巨猿属于"厚"釉质类型, 但非"超厚"类型, 低于奥兰诺古猿、傍人、南非早期人属; 巨猿与某些中新世古猿 (如原康修尔猿尼安萨种、非洲古猿)、南方古猿、东非早期人属、亚洲直立人以及现代人、现生卷尾猴的相对釉质厚度指数相近。巨猿的厚釉质特征与其食性和环境适应密切相关, 使得牙齿具有非常强的抗磨损功能, 能够适应长时间的咀嚼和研磨食物。从釉质厚度的系统演化角度推测, 厚釉质应该是人类祖先的特征性状, 巨猿有可能是早期人类支系演化过程中的一个特化旁支, 同时也不排除巨猿是从某种具有厚釉质的中新世古猿旁支平行演化而来的可能性。     

The articular surface of the temporal bone in certain fossil hominoids

Although quantitative variations exist between living Man ( Homo sapiens sapiens ) and the extant great apes ( Pongo, Pan, Gorilla ) in such features of the articular surface of the temporal bone (a part of the temporomandibular joint) as the proportionate development of the postglenoid tubercle, the relative prominence of the articular tubercle and the slope of its posterior face, these do not individually effect a clear differentiation between the four extant genera. But in multivariate combination of these features, although Pan and Pongo are relatively closely associated, Gorilla and Homo sapiens sapiens are distinct, and also clearly differentiated from each other. The differences between genera of extant apes are, on average, as great as those between extant Man and individual apes.
As portrayed by such multivariate compound, this anatomical region in four fossil groups displays a unique configuration differentiating Homo sapiens neanderthalensis, Homo erectus pekinensis, Australopithecus africanus and Australopithecus robustus both from one another and from extant types. The differences are such that the fossil species lie uniquely and not intermediate between extant groups.
Definable age changes in this multivariate compound occur in both Man and apes but neither these, nor overall differences between adults, appear to be associated with marked contrasts in the pattern of jaw movement. It would thus seem improbable that inferences can be made from these features about the type of jaw movement that characterized the several fossil groups.     

巫山龙骨坡似人下颌属于猿类

本文将巫山似人下颌及其牙齿与东非早更新世人属 ,Dmanisi直立人以及元谋的禄丰古猿等做了比较。结果发现巫山标本的尺寸比前二者都小得多 ,而与后者很相符。巫山标本被有些人作为归属人属根据的那些特征大多是人和猿共具者 ,其中前臼齿齿根分叉则是在人类罕见 ,却是禄丰古猿的特征之一 ,前臼齿前接触面位置和跟座比例则反映猿类特征。最接近巫山下颌者是禄丰古猿 ,其间有否祖裔关系尚待更多标本来论证。     

Foot bones from Omo: implications for hominid evolution

We reanalyze a hominid talus and calcaneus from Omo dating to 2.2 mya and 2.36 mya, respectively. Although both specimens occur at different localities and times, both tarsals articulate well together, suggesting a single taxon on the basis of size and function. We attribute these foot bones to early Homo on the basis of their morphology. The more modern-like tarsal morphology of these Omo foot bones makes them very similar to a talus from Koobi Fora (KNM-ER 813), a specimen attributed to Homo rudolfensis or Homo erectus. Although the Omo tarsals are a million years younger than the oldest known foot bones from Hadar, both localities demonstrate anatomical differences representing two distinct morphological patterns. Although all known hominid tarsals demonstrate clear bipedal features, the tarsal features noted below suggest that biomechanical changes did occur over time, and that certain features are associated with different hominid lineages (especially the robust australopithecines).     

Heterochronic processes in human evolution: An ontogenetic analysis of the hominid pelvis

Changes in pelvic shape in human ontogeny and hominid phylogeny suggest that the heterochronic processes involved differ greatly from the neotenic process traditionally described in the evolution of the skull. The morphology of 150 juvenile and adult pelves of African apes, 60 juvenile and adult pelves of modern humans, two adult pelves and a juvenile hip bone of australopithecines (Sts 14, AL 288, MLD 7) was studied. Multivariate results, ontogenetic allometries, and growth curves confirm that the pelvic growth pattern in humans differs markedly from those of the African apes. The results permit the following conclusions. First, the appearance of a new feature (acetabulo-cristal buttress and cristal tubercle) at the time of human birth allows the addition of traits, such as the attainment of a proportionally narrower pelvis, with more sagittally positioned iliac blades. Pelvic proportions and orientation change progressively in early childhood as bipedalism is practiced. Other changes in pelvic proportions occur later with the adolescent growth spurt. Second, comparison of juvenile and adult australopithecines to modern humans indicates that 1) some pelvic traits of adult Australopithecus resemble those of neonate Homo; 2) the pelvic growth of Australopithecus was probably closer to that of apes, than to that of humans; and 3) prolonged growth in length of hindlimb and pelvis after sexual maturity seems to be a unique feature of Homo. The position of the acetabulo-cristal buttress and of the cristal tubercle on the ilium are similar in adult Australopithecus and neonate Homo suggesting that this feature may have been displaced later during hominid evolution. Progressive displacement of the acetabulo-cristal buttress on the ilium occurs both during hominid evolution (from Australopithecus to Homo sapiens) and human growth (from neonate to adult). This suggests peramorphic evolution of the pelvic morphology of hominids combining three processes of recapitulation (pre-displacement, acceleration and time hypermorphosis). The results lend credence to the hypothesis that no single heterochronic process accounts for all human evolutionary change; rather this reflects a combination of relative changes in growth rhythm and duration, including other perturbations, such as the appearance of new morphological features. Am J Phys Anthropol 105:441–459, 1998. © 1998 Wiley-Liss, Inc.     

Middle Pleistocene human cranium from Tangshan (Nanjing), Southeast China: a new reconstruction and comparisons with Homo erectus from Eurasia and Africa

The morphology and affinities of early and middle Pleistocene Homo erectus in East Asia have been explored since the late nineteenth century. A fragmentary hominid cranium (Nanjing no.1) recovered in Tangshan near Nanjing, China bears directly on these issues. In the present study, the morphological features of Nanjing no.1 are described and compared with Homo erectus from both Eurasia and Africa. Our results indicate that this middle Pleistocene hominid fossil should be referred to as Homo erectus. The sharing of typical Homo erectus features with African and European counterparts demonstrates that Homo erectus is a widely distributed lineage that evolved during the million years after its Pliocene origins. The differences between Nanjing no.1 and Zhoukoudian suggest certain level of regional variation in East Asian Homo erectus.     

Nasal morphology and the emergence of Homo erectus

Modern humans, among extant hominoids, possess a unique projecting, external nose whose basic structure is reflected in a series of skeletal features including nasal bone convexity, an internasal angle, lateral nasal aperture eversion, prominence and anterior positioning of the anterior nasal spine, an acute angle of the subnasal alveolar clivus, and an expansion of the breadth of the nasal bones relative to that of the piriform aperture. This anatomy appears with the emergence of Homo erectus ca. 1.6 million years ago. Although it undoubtedly evolved in the context of craniofacial and dental reduction during hominid evolution, it appears to have been primarily a response to the need for moisture conservation in an arid environment via turbulence enhancement and ambient cooling of expired air. Its appearance at this time in hominid evolution, in conjunction with the presence of a fatigue-resistant locomotor anatomy characteristic of archaic members of the genus Homo, indicates a shift to increasingly prolonged bouts of activity in open and arid environments.     

Size, shape, and asymmetry in fossil hominins: the status of the LB1 cranium based on 3D morphometric analyses

The unique set of morphological characteristics of the Liang Bua hominins (Homo floresiensis) has been attributed to explanations as diverse as insular dwarfism and pathological microcephaly. This study examined the relationship between cranial size and shape across a range of hominin and African ape species to test whether or not cranial morphology of LB1 is consistent with the basic pattern of static allometry present in these various taxa. Correlations between size and 3D cranial shape were explored using principal components analysis in shape space and in Procrustes form space. Additionally, patterns of static allometry within both modern humans and Plio-Pleistocene hominins were used to simulate the expected cranial shapes of each group at the size of LB1. These hypothetical specimens were compared to LB1 both visually and statistically. Results of most analyses indicated that LB1 best fits predictions for a small specimen of fossil Homo but not for a small modern human. This was especially true for analyses of neurocranial landmarks. Results from the whole cranium were less clear about the specific affinities of LB1, but, importantly, demonstrated that aspects of facial morphology associated with smaller size converge on modern human morphology. This suggests that facial similarities between LB1 and anatomically modern humans may not be indicative of a close relationship. Landmark data collected from this study were also used to test the degree of cranial asymmetry in LB1. These comparisons indicated that the cranium is fairly asymmetrical, but within the range of asymmetry exhibited by modern humans and all extant African ape species. Compared to other fossil specimens, the degree of asymmetry in LB1 is moderate and readily explained by the taphonomic processes to which all fossils are subject. Taken together, these findings suggest that H. floresiensis was most likely the diminutive descendant of a species of archaic Homo, although the details of this evolutionary history remain obscure.     

Patterns of tooth crown size and shape variation in great apes and humans and species recognition in the hominid fossil record

It has been suggested that patterns of craniodental variation in living hominids (Gorilla, Homo, Pan, and Pongo) may be useful for evaluating variation in fossil hominid assemblages. Using this approach, a fossil sample exhibiting a pattern of variation that deviates from one shared among living taxa would be regarded as taxonomically heterogeneous. Here we examine patterns of tooth crown size and shape variation in great apes and humans to determine 1) if these taxa share a pattern of dental variation, and 2) if such a pattern can reliably discriminate between samples that contain single species and those that contain multiple species. We use parametric and nonparametric correlation methods to establish the degree of pattern similarity among taxa, and randomization tests to assess their statistical significance. The results of this study show that extant hominids do not share a pattern of dental size variation, and thus these taxa cannot be used to generate expectations for patterns of size variation in fossil hominid species. The hominines (Gorilla, Homo, and Pan) do share a pattern of shape variation in the mandibular dentition; however, Pongo is distinct, and thus it is unclear which, if either, pattern should be expected in fossil hominids. Moreover, in this case, most combined-species samples exhibit patterns of shape variation that are similar to those for single hominine species samples. Thus, although a common pattern of shape variation is present in the mandibular dentition, it is not useful for recognizing taxonomically mixed paleontological samples.     

The posterior border of the sphenoid greater wing and its phylogenetic usefulness in human evolution

The elucidation of patterns of cranial skeletal maturation and growth in fossil hominids is possible not only through dental studies but also by mapping different aspects of ossification in both extant African apes and humans. However, knowledge of normal skeletal development in large samples of extant great apes is flimsy. To remedy this situation, this paper offers an extensive survey and thorough discussion of the ossification of the posterior border of the sphenoid greater wing. Indeed, this area provides much information about basicranial skeletal maturation. We investigate three variants: the absence of the foramen spinosum and the position of both the foramen spinosum and the foramen ovale in relation to the sphenosquamosal suture. Providing original data about humans and 1,425 extant great ape skulls and using a sample of 64 fossil hominids, this study aimed to test whether different ossification patterns occurred during the course of human evolution. The incidence of three derived morphologies located on the posterior border of the sphenoid greater wing increases during human evolution at different geological periods. The evolutionary polarity of these three derived morphologies is assessed by outgroup comparison and ontogenetic methods. During human evolution, there is a clear trend for the foramen spinosum to be present and wholly located on the posterior area of the sphenoid greater wing. Moreover, in all the great ape species and in Australopithecus afarensis, the sphenosquamosal suture may split the foramen ovale. Inversely, the foramen ovale always lies wholly within the sphenoid greater wing in Australopithecus africanus, robust australopithecines, early Homo, H. erectus (and/or H. ergaster), and Homo sapiens. From ontogenetic studies in humans, we conclude that, during human evolution, the ossification of the posterior area of the sphenoid greater wing progressively surrounded the middle meningeal artery (passing through the foramen spinosum) and the small meningeal artery (passing through the foramen ovale). Am J Phys Anthropol 107:387–399, 1998. © 1998 Wiley-Liss, Inc.     

Palatine fenestrae,the orangutan and hominoid evolution

Although most mammals develop relatively large double anterior palatine fenestrae that patently communicate with the nasal cavity, four extant primates—Homo sapiens, Pongo, Pan andGorilla—do not. While these four have closed-down these foramenal structures,Homo sapiens andPongo are unique in forming a single foramen palatally. Among fossil taxa,Homo, Australopithecus, Sivapithecus (=Ramapithecus) andRudapithecus also develop a single foramen palatally. Dryopithecines, the presumed fossil apes, preserve the two patent fenestrae. In light of dental features that are considered diagnostically “hominid,” which are also found in the orangutan, it is suggested that this “ape,” rather thanPan, is phylogenetically closer toHomo.