Total Morphological Pattern Research Articles

Neanderthal cranial remains from Baume Moula-Guercy (Soyons, Ardèche, France).

We provide the first comparative description of the Guercy 1 cranium and isolated cranial fragments from Baume Moula-Guercy and examine their affinities to European Preneanderthals, Neanderthals, and Homo sapiens. The Moula-Guercy hominins derive from deposits chronostratigraphically and biostratigraphically dated to the Eemian Interglacial (MIS 5e). For comparisons we compiled a sample of European and Southwest Asian subadult-adult Middle-to-Late Pleistocene hominins (≈MIS 14-MIS 2; N = 184). This sample represents a Preneanderthal-Neanderthal group and a H. sapiens group, both of which were further divided into three time-successive subgroups defined by associated marine isotope stages (MIS). Metric and morphological observations were made on the original fossils and a virtual reconstruction of Guercy 1. Developmental age and sex and the minimum-maximum number of individuals were assessed. Guercy 1 represents the remains of a late stage adolescent (≈15-16.0 years) female. Morphological and metric data combine to associate the total morphological pattern expressed in Guercy 1 with our MIS 7-MIS 5e ("Early Neanderthal") subgroup. Some features, especially those related to the frontal, suggest linkage to a paleodeme comprising the Moula-Guercy, Artenac, La Chaise Abri Suard and, possibly, the Biache-Saint-Vaast samples. Remains of MIS 7-MIS 5e Neanderthals are rare and fragmentary, especially those dated to the Last Interglacial. The Baume Moula-Guercy sample provides new insights into the total morphological pattern expressed in MIS 5e Neanderthals. Further, our results support earlier suggestions that MIS 7-MIS 5e European hominins represent a morphotype that is distinct from both earlier and later members of the Preneanderthal-Neanderthal group.

An Experiment on Age-Related Characteristics of the Reaction of Lung Tissue and Surfactant to Hypobaric Hypoxia and Hyperbaric Hyperoxia

A comparative analysis of morphometric changes in lung tissue was carried out in an experiment on white rats of different postnatal age (4 weeks, 2 months, and 24 months) with a simultaneous estimation of surfactant stability during exogenous hypoxia and hyperbaric oxygenation. The morphometric indices were studied and the total morphological pattern of lung tissue was described via light microscopy and systemic quantitative analysis, and the stability of the alveolar-lining complex was estimated with the Pattl method. The studies demonstrated that a complex of structural changes develops after a hypo- and hyperoxic effect: heterogeneity and an increase in the airiness of the lung tissue, the width of the interalveolar septa, and the thickness of the bronchial and vascular walls, the degree and severity of which depends on age. An increase in surfactant stability was detected in all animals of the experimental groups, except for 2-month-old rats subjected to a hypoxic effect. A natural increase in morphometric indices was registered with age in intact animals.

Functional aspects of metatarsal head shape in humans, apes, and Old World monkeys

Modern human metatarsal heads are typically described as “dorsally domed,” mediolaterally wide, and dorsally flat. Despite the apparent functional importance of these features in forefoot stability during bipedalism, the distinctiveness of this morphology has not been quantitatively evaluated within a broad comparative framework. In order to use these features to reconstruct fossil hominin locomotor behaviors with any confidence, their connection to human bipedalism should be validated through a comparative analysis of other primates with different locomotor behaviors and foot postures, including species with biomechanical demands potentially similar to those of bipedalism (e.g., terrestrial digitigrady). This study explores shape variation in the distal metatarsus among humans and other extant catarrhines using three-dimensional geometric morphometrics (3DGM). Shape differences among species in metatarsal head morphology are well captured by the first two principal components of Procrustes shape coordinates, and these two components summarize most of the variance related to “dorsal doming” and “dorsal expansion.” Multivariate statistical tests reveal significant differences among clades in overall shape, and humans are reliably distinguishable from other species by aspects of shape related to a greater degree of dorsal doming. Within quadrupeds, terrestrial species also trend toward more domed metatarsal heads, but not to the extent seen in humans. Certain aspects of distal metatarsus shape are likely related to habitual dorsiflexion of the metatarsophalangeal joints, but the total morphological pattern seen in humans is distinct. These comparative results indicate that this geometric morphometric approach is useful to characterize the complexity of metatarsal head morphology and will help clarify its relationship with function in fossil primates, including early hominins.

Reconciling the convergence of supraspinous fossa shape among hominoids in light of locomotor differences

Differences in scapular morphology between modern humans and the African and lesser apes are associated with the distinct locomotor habits of these groups. However, several traits, particularly aspects of the supraspinous fossa, are convergent between Homo and Pongo-an unexpected result given their divergent locomotor habits. Many morphological assessments of the scapula rely on the limited number of static landmarks available, and traditional approaches like these tend to oversimplify scapular shape. Here, we present the results of two geometric morphometric (GM) analyses of hominoid supraspinous fossa shape-one employing five homologous landmarks and another with 83 sliding semilandmarks-alongside those of traditional methods to evaluate if three-dimensional considerations of fossa shape afford more comprehensive insights into scapular shape and functional morphology. Traditional measures aligned Pongo and Homo with narrow and transversely oriented supraspinous fossae, whereas African ape and Hylobates fossae are broader and more obliquely situated. However, our GM results highlight that much of the convergence between Homo and Pongo is reflective of their more medially positioned superior angles. These approaches offered a more complete assessment of supraspinous shape and revealed that the Homo fossa, with an intermediate superior angle position and moderate superoinferior expansion, is actually reminiscent of the African ape shape. Additionally, both Pongo and Hylobates were shown to have more compressed fossae, something that has not previously been identified through traditional analyses. Thus, the total morphological pattern of the Pongo supraspinous fossa is unique among hominoids, and possibly indicative of its distinctive locomotor habits.

The Middle Miocene Ape Pierolapithecus catalaunicus Exhibits Extant Great Ape-Like Morphometric Affinities on Its Patella: Inferences on Knee Function and Evolution

The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional behavior and locomotion of these taxa based on isolated elements only. The fossil great ape Pierolapithecus catalaunicus (IPS 21350 skeleton; 11.9 Ma) exhibits a relatively wide and shallow thorax with moderate hand length and phalangeal curvature, dorsally-oriented metacarpophalangeal joints, and loss of ulnocarpal articulation. This evidence reveals enhanced orthograde postures without modern ape-like below-branch suspensory adaptations. Therefore, it has been proposed that natural selection enhanced vertical climbing (and not suspension per se) in Pierolapithecus catalaunicus. Although limb long bones are not available for this species, its patella (IPS 21350.37) can potentially provide insights into its knee function and thus on the complexity of its total morphological pattern. Here we provide a detailed description and morphometric analyses of IPS 21350.37, which are based on four external dimensions intended to capture the overall patellar shape. Our results reveal that the patella of Pierolapithecus is similar to that of extant great apes: proximodistally short, mediolaterally broad and anteroposteriorly thin. Previous biomechanical studies of the anthropoid knee based on the same measurements proposed that the modern great ape patella reflects a mobile knee joint while the long, narrow and thick patella of platyrrhine and especially cercopithecoid monkeys would increase the quadriceps moment arm in knee extension during walking, galloping, climbing and leaping. The patella of Pierolapithecus differs not only from that of monkeys and hylobatids, but also from that of basal hominoids (e.g., Proconsul and Nacholapithecus), which display slightly thinner patellae than extant great apes (the previously-inferred plesiomorphic hominoid condition). If patellar shape in Pierolapithecus is related to modern great ape-like knee function, our results suggest that increased knee mobility might have originally evolved in relation to enhanced climbing capabilities in great apes (such as specialized vertical climbing).

The Myth of the East African 'Bushmen'

Recent genetic studies of living African peoples have suggested that the KhoiSan in particular are of very ancient stock and that they share some ancient genetic features with living East Africans. Archaeological and linguistic evidence for an ancient KhoiSan presence in East Africa has been used to support these arguments. A re-examination of the archaeological evidence does not support this stance. In particular, the bulk of the osteological evidence for KhoiSan presence in East Africa is flawed because it is drawn from a typological context where individual osteologicalfeatures were interpreted as KhoiSan and the total morphological pattern was not considered. More recent studies of archaeological specimens and living East Africans have not confirmed any KhoiSan linkage with East Africa. Linguistic evidence is also equivocal and the clicks found in East Africa may represent the remains of ancient linguistic phonemes rather than remnants of KhoiSan languages. Without the support of archaeological and linguistic evidence, the genetic similarities of East and South Africans should be seen as a more distant commonality of underlying genetic features of all Africans rather than a specific KhoiSan genetic identity. (The terminology used in this paper conforms to that of Jenkins & Tobias [1977]. The spelling of KhoiSan was adopted by the session on Nomenclature of People at the Origins of Humanity Workshop at Stellenbosch in September 2002 as part of the HSRC Africa Genome Initiative.)

Gough's Cave 1 (Somerset, England): an assessment of body size and shape

Stature, body mass, and body proportions are evaluated for the Cheddar Man (Gough's Cave 1) skeleton. Like many of his Mesolithic contemporaries, Gough's Cave 1 evinces relatively short estimated stature (ca. 166.2 cm [5′ 5′]) and low body mass (ca. 66 kg [146 lbs]). In body shape, he is similar to recent Europeans for most proportional indices. He differs, however, from most recent Europeans in his high crural index and tibial length/trunk height indices. Thus, while Gough's Cave 1 is characterized by a total morphological pattern considered ‘cold-adapted’, these latter two traits may be interpreted as evidence of a large African role in the origins of anatomically modern Europeans.

Cross-sectional morphology of the SK 82 and 97 proximal femora.

Computed tomography scans of the proximal femoral shaft of the South African "robust" australopithecine, A. robustus, reveal a total morphological pattern that is similar to the specimen attributed to A. boisei in East Africa but unlike that of Homo erectus or modern human femora. Like femora attributed to H. erectus, SK 82 and 97 have very thick cortices, although they do not have the extreme increase in mediolateral buttressing that is so characteristic of H. erectus. And unlike H. erectus or modern humans, their femoral heads are very small relative to shaft strength. These features are consistent with both increased overall mechanical loading of the postcranial skeleton and a possibly slightly altered pattern of bipedal gait relative to that of H. erectus and modern humans.

What's your angle? Size correction and bar-glenoid orientation in "Lucy" (A.L. 288-1)

There has been much debate as to the locomotor repertoire of Lucy (A.L. 288-1) and other specimens of Australopithecus afarensis, ranging from fully committed bipeds to species that spent a significant time in the trees as well as on the ground. We examined the bar–glenoid angle, a character purported to indicate arboreal propensities, and its implications for this specific debate and the more general challenge of extracting behavioral information from fossils. We examined the bar–glenoid angle in ontogenetic samples of Pan paniscus, Pan troglodytes, Gorilla gorilla gorilla, Gorilla gorilla beringei, Pongo pygmaeus, Homo sapiens, and A.L. 288-1 (“Lucy”). We found that there is no allometry in the bar–glenoid angle for the great apes, but a weak correlation for humans. Moreover, the data scatters for the African apes and humans converge at the smaller size ranges, and Lucy's value for bar–glenoid angle falls precisely in this area of overlap. Therefore, we conclude that the bar–glenoid angle is not tightly correlated with function and, as such, cannot be used as a morphological signal of arboreal behavior, especially in the smaller size ranges, at which arboreal and nonarboreal species overlap. Our work does not resolve issues concerning Lucy's precise locomotor repertoire but adds new information to consider. The total morphological pattern, plus an appreciation of the underlying variance in morphological and behavioral characters in extant species, is key for making functional inferences from the morphology of fossils.

Morphological affinities of the proximal ulna from Klasies River main site: archaic or modern?

The Middle Stone Age (MSA) asociated hominids from Klasies River Mouth (KRM) have taken on a key role in debate about the origins of modern humans, with their craniofacial remains seen as either representing the earliest well-dated modern humans in southern Africa or orthognathic late archaic humans. Diagnostic postcranial remains from Klasies are few, but one specimen—a proximal right ulna from the lower SAS member—is useful for assessing the morphological affinities of these hominids. Canonical variates analysis using 14 proximal ulnar dimensions and comparative data from European, west Asian and African archaic humans, and Levantine Mousterian, European Upper Paleolithic, African Epipaleolithic and diverse recent modern human samples (many of recent African descent) were employed to assess the morphological affinities of this specimen. Results suggest an archaic total morphological pattern for the Klasies ulna. Analysis of diaphyseal cross-sectional geometry reveals an ulnar shaft with relatively thick cortical bone, but the specimen cannot be readily distinguished from Neandertals or early anatomically modern humans on the basis of shaft cross-sectional properties. If the isolated ulna from Klasies is indicative of the general postcranial morphology of these hominids, then the MSA-associated humans from KRM may not be as modern as has been claimed from the craniofacial material. It is possible also that the skeletal material from KRM reflects mosaic evolution—retention of archaic postcranial characteristics, perhaps indicating retention of archaic habitual behavior patterns, in hominids that were becoming craniofacially modern.

The question of robusticity and the relationship between cranial size and shape inHomo sapiens

Although cranial gracility is generally considered to be a characteristic feature of modern skulls, a quantification of the degree of development of cranial superstructures discloses varying levels of robusticity in certain recent and sub-recent populations. In order to account for these structures, biomechanical interpretations in terms of masticatory stress and the effects of structural constraints have been put forward. This paper examines the multivariate relationships between robusticity and cranial dimensions in modern humans through canonical correlation and principal components analyses. These analyses reveal a very significant association between robusticity and cranial size, by which the larger the size of the skull, the greater the development of the cranial superstructures. In this context, size is biased towards maximum cranial length, various measures of upper facial breadth, basion–nasion length and palato–dental size. A statistically less important relationship between robusticity and cranial shape reveals that there are two main circumstances in which a modern skull will develop superstructures, in either very large crania, independent of the breadth of the vault, or in very narrow ones with large teeth. The cranial superstructures are not only strongly influenced by certain cranial dimensions, but are inter-correlated in their expression. These morphological features should not be treated as independent phylogenetic traits. The majority of recent crania are relatively small and gracile, clearly the result of a common temporal trend in the evolution of modern human cranial diversity. Although not unique in their level of robusticity among recent human groups, Australian aboriginals are the only population to show a relationship between robusticity and cranial breadth. It is suggested that the total morphological pattern observed in Australia does not reflect a plesio-morphic condition, but the specific history of occupation of that continent favouring size reduction with the maintenance of robusticity. Finally, it is shown that most early modern fossils are comparatively large and robust. It is suggested that the definition of a modern cranial form should be disassociated from the concept of gracility, only observed in some recent human populations.

Analysis of a microcephalic child from the late period (ca. 1100–1700 A.D.) of Central California

Microcephaly is a severe developmental abnormality which is induced either genetically or environmentally. The archaeological evidence for the occurrence of this abnormality is minimal. Out of six possible cases, only three have been published; all are adult and represented solely by cranial remains. The focus of the current study is the nearly complete skeleton of a 3-year-old child recovered during archaeological excavations in San Jose, California. The individual is compared to a sample of 184 California Indians, ranging from 0.5 to 5 years, which were also recovered from archaeological excavations. In order to determine if microcephaly was the only disorder represented, metrical comparisons of the skull and postcrania and gross morphological comparisons of endocranial casts were made. Based on these comparisons the individual was determined to have a cranial vault size comparable to 6-month-old infants (630 cc), a facial skeleton equivalent to the 9-month-old to 2-year-old age groups, and a reduced stature. Due to the mosaic nature of the skull, the observed morphology was interpreted in terms of functional cranial components. Severe malformation of the orbital aspect of the frontal lobes was found in conjunction with a significant reduction in size of the cerebral cortex and left temporal lobe. On the basis of this analysis, the individual was found to exhibit the total morphological pattern associated with microcephaly. A differential diagnosis of other possible genetic disorders is also presented.

A Human Skull of the Epi-Jomon Period from the Minami-Usu Six Site, Date, Hokkaido

An adult female skull of the Epi-Jomon period (Esan culture) found at the Minami-Usu 6 site, Date, southern Hokkaido, was measured and described. Metrically, the skull was characterized, among other things, by a relatively long vault and a moderately high upper face. Morphological observations revealed that the facial skeleton of the skull was as a whole reduced in size as compared with that of Jomon crania, while attrition of the teeth was well advanced arid had reached Stage III or IV, as is frequently seen in Jomon crania. PENROSE's shape distances, based on 21 measurements, showed that the Minami-Usu 6 skull was closer to the skulls of the Ainu series than to those of the Jomon series in Honshu. Of the six cranial indices which have been effective in discriminating between Ainu and Jomon crania, four indices suggested the close affinity of the Minami-Usu 6 skull with the Ainu series. With regard to the indices of facial flatness, the frontal and simotic indices of flatness of the Minami-Usu 6 skull were intermediate between the averages of the Ainu and Jomon series, with only the zygomaxillary index of flatness exceeding the averages of both the Ainu and Jomon series. A likelihood ratio analysis of the non-metric cranial variants applied for the Ainu and modern Japanese, based on 29 traits, indicated that the Minami-Usu 6 skull was far more likely to have come from the Ainu population than from the Japanese population. Taking all the results obtained from this study into consideration, it was concluded that the total morphological pattern of the Minami-Usu 6 skull was slightly closer to that of the Ainu series, especially to that of the Ainu in southwestern Hokkaido, than to that of the Jomon series in Honshu.

The postcranium of Miocene hominoids: Were dryopithecines merely “dental apes”?

This paper reviews the non-dental morphological configuration of Miocene hominoids with special reference to the hypothesis of linear relationships between certain fossil species and living analogues. Metrical analysis of the wrist shows thatDryopithecus africanus andPliopithecus vindobonensis are unequivocally affiliated with the morphological pattern of quadrupedal monkeys. Similar analyses of the fossil hominoid elbow shows that they are more cercopithecoid-like than hominoid-like. Multivariate analysis of theP. vindobonensis shoulder in the matrix of extant Anthropoidea indicate that this putative hylobatine fossil shows no indication of even the initial development of hominoid features. The total morphological pattern of theD. africanus forelimb as assessed by principal coordinates analysis of allometrically adjusted shape variables has little resemblance toPan. Likewise, the feet and proximal femora of the Miocene fossils are unlike any living hominoid species. Even theD. africanus skull is similar to extant cercopithecoids in several features. Although ancestors cannot be expected to resemble descendants in every way, the striking dissimilarity between Miocene and extant hominoids seems to eliminate the consideration of a direct ancestor-descendant relationship between specific Miocene and modern forms.

Squatting among the neandertals: A problem in the behavioral interpretation of skeletal morphology

The analysis of the Neandertal and Skhul hominid metric and non-metric lower limb variations which have been considered indicative of squatting suggests that squatting was a common position of repose among these Pleistocene hominids. Although the total morphological pattern of the Neandertals supports this conclusion, few of the variations commonly associated with squatting provide conclusive evidence of previous habitual squatting. It is necessary to consider each variation with reference to its etiology and its association in the total morphological pattern before deriving similar behavioral interpretations from the skeletal morphology.

Sagittal cresting in the South African australopithecines

AbstractThe evidence for sagittal cresting, and more generally the position of the temporal lines is reviewed in the South African australopithecine sample. The position of the lines is dependent on both the allometric relation of the masticatory apparatus to cranial size and on individual variation. In the Swartkrans specimens, with generally bigger body size, the influence of allometry predominates, actually overshadowing the influence of individual variation. At Sterkfontein and Makapansgat with generally smaller body size and a resulting smaller allometric ratio, individual variation has a greater influence. Of the eleven adult South African specimens, the four largest are crested. The one smaller crested specimen comes from Sterkfontein. The crested Makapan specimen is intermediate in size. The pattern of australopithecine cresting is somewhat different from other hominoids, and is part of a total morphological pattern suggesting adaptation to a diet requiring powerful crushing during mastication.

Gigantopithecus and its relationship to Australopithecus.

AbstractGigantopithecus blacki and G. bilaspurensis are compared to P. gorilla and Australopithecus. The total morphological pattern of Gigantopithecus mandibles is more similar to Australopithecus than to P. gorilla. Two major points are raised. (1) G. blacki might be considered an aberrant hominid rather than an aberrant pongid. (2) G. bilaspurensis can be considered an equally likely candidate, along with Ramapithecus, for possible hominid ancestry.

A multivariate study of evolutionary change in the hominid cranial vault and some evolution rates

Multivariate analysis is used to describe the total morphological pattern of the hominid cranial vault, and to obtain distances between samples of Plio-Pleistocene Hominidae. Such techniques provide a means of quantifying phyletic change within a lineage, and therefore usefully complement the traditional Linnean nomenclature. When divided by elapsed time, the multivariate distances between groups provide a measure of the rate of evolution of a character complex and such data are given for the hominid cranial vault over the Quaternary as a whole, and for more detailed changes within Upper Pleistocene H. sapiens. The evolutionary significance of the observed rates, and their implications for the construction of phyletic schemes, are discussed.