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1.
J Hum Evol ; 189: 103470, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38552260

RESUMEN

Sex is a biological trait fundamental to the study of hominin fossils. Among the many questions that can be addressed are those related to taxonomy, biological variability, sexual dimorphism, paleoobstetrics, funerary selection, and paleodemography. While new methodologies such as paleogenomics or paleoproteomics can be used to determine sex, they have not been systematically applied to Pleistocene human remains due to their destructive nature. Therefore, we estimated sex from the coxal bone of the newly discovered pelvic remains of the Regourdou 1 Neandertal (Southwest France, MIS 5) based on morphological and metric data employing two methods that have been recently revised and shown to be reliable in multiple studies. Both methods calculate posterior probabilities of the estimate. The right coxal bone of Regourdou 1 was partially reconstructed providing additional traits for sex estimation. These methods were cross validated on 14 sufficiently preserved coxal bones of specimens from the Neandertal lineage. Our results show that the Regourdou 1 individual, whose postcranial skeleton is not robust, is a male, and that previous sex attributions of comparative Neandertal specimens are largely in agreement with those obtained here. Our results encourage additional morphological research of fossil hominins in order to develop a set of methods that are applicable, reliable, and reproducible.


Asunto(s)
Hominidae , Hombre de Neandertal , Animales , Humanos , Masculino , Hombre de Neandertal/anatomía & histología , Fósiles , Genómica , Paleontología , Francia
2.
J Hum Evol ; 151: 102925, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33412453

RESUMEN

The calcium isotopic composition (δ44/42Ca) of bone and tooth enamel can be used for dietary reconstructions of extant and extinct mammals. In natural conditions, the δ44/42Ca value of bone and teeth varies according to dietary intake with a constant isotopic offset of about -0.6‰. Owing to the poor conservation of collagen, carbon (C), and nitrogen (N) isotopic compositions of the Regourdou Mousterian site (MIS 5, Dordogne, France) previously failed to provide any paleodietary information. Therefore, to reconstruct the trophic chain, we have measured calcium (Ca) isotopes from fossil bone samples of the fauna from the Regourdou site, as well as from three bone samples of the Regourdou 1 Neandertal specimen. The results show a taxon-dependent patterning of the Ca isotopic compositions: herbivores generally have higher δ44/42Ca values than carnivores. All the δ44/42Ca values of Regourdou 1 are low (<-1.6‰), placing this specimen amid carnivores. Using a bone-muscle Ca isotopic offset determined on extant animals, we further show that the δ44/42Ca value of the Regourdou 1 diet, and that of most carnivores, cannot be accounted for by the consumption of meat only, as plants and meat have indistinguishable δ44/42Ca values. Mass balance calculations indicate that the low δ44/42Ca values of the Neandertal's carnivorous diet are explained by the ingestion of bone marrow containing as little as 1% trabecular bone. Our results show that the Regourdou 1 Neanderthal consumed a mixture of various herbivorous prey, as well as trabecular bone, which probably occurred when marrow was ingested, by accident or intentionally.


Asunto(s)
Huesos/química , Isótopos de Calcio/análisis , Dieta , Fósiles , Hombre de Neandertal , Vertebrados , Animales , Francia
3.
Am J Phys Anthropol ; 171(2): 242-259, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31710710

RESUMEN

OBJECTIVES: A marked asymmetry was previously reported in the sacral alae and S1-L5 facets orientation of the Neandertal individual Regourdou 1. Here, we provide a detailed description and quantification of the morphology and degree of asymmetry of this sacrum. MATERIAL AND METHODS: Regourdou 1 was compared to a modern human sample composed of 24 females and 17 males, and to other Neandertal individuals. Both traditional and geometric morphometric analyses were used in order to quantify the degree of sacral asymmetry of Regourdou 1. RESULTS: The asymmetry of both sacral alae and facets orientation substantially exceeds directional and absolute asymmetry of the healthy modern sample. Regourdou 1 shows a considerably shorter right ala, which is absolutely and relatively outside of the modern and Neandertal variations. CONCLUSION: Regourdou 1 shows marked sacral asymmetry that probably originated in early ontogenetic development. An asymmetric sacrum reflects asymmetric load dissipation and could relate to other morphological abnormalities observed in the skeleton, especially the mild scoliosis of the spine and the asymmetry of the femoral diaphyses. Further investigation is necessary to elucidate the relationship between those morphologies as well as a potential impact on the life of the individual.


Asunto(s)
Fósiles/anatomía & histología , Hombre de Neandertal/anomalías , Sacro/anomalías , Animales , Francia
4.
J Hum Evol ; 133: 61-77, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31358184

RESUMEN

The abundant femoral assemblage of Homo naledi found in the Dinaledi Chamber provides a unique opportunity to test hypotheses regarding the taxonomy, locomotion, and loading patterns of this species. Here we describe neck and shaft cross-sectional structure of all the femoral fossils recovered in the Dinaledi Chamber and compare them to a broad sample of fossil hominins, recent humans, and extant apes. Cross-sectional geometric (CSG) properties from the femoral neck (base of neck and midneck) and diaphysis (subtrochanteric region and midshaft) were obtained through CT scans for H. naledi and through CT scans or from the literature for the comparative sample. The comparison of CSG properties of H. naledi and the comparative samples shows that H. naledi femoral neck is quite derived with low superoinferior cortical thickness ratio and high relative cortical area. The neck appears superoinferiorly elongated because of two bony pilasters on its superior surface. Homo naledi femoral shaft shows a relatively thick cortex compared to the other hominins. The subtrochanteric region of the diaphysis is mediolaterally elongated resembling early hominins while the midshaft is anteroposteriorly elongated, indicating high mobility levels. In term of diaphyseal robusticity, the H. naledi femur is more gracile that other hominins and most apes. Homo naledi shows a unique combination of characteristics in its femur that undoubtedly indicate a species committed to terrestrial bipedalism but with a unique loading pattern of the femur possibly consequence of the unique postcranial anatomy of the species.


Asunto(s)
Fémur/anatomía & histología , Fósiles/anatomía & histología , Hominidae/anatomía & histología , Animales , Densidad Ósea , Diáfisis/anatomía & histología , Diáfisis/fisiología , Fémur/fisiología , Cuello Femoral/anatomía & histología , Cuello Femoral/fisiología , Hominidae/fisiología , Sudáfrica
5.
J Hum Evol ; 128: 17-44, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30825980

RESUMEN

Regourdou is a well-known Middle Paleolithic site which has yielded the fossil remains of a minimum of two Neandertal individuals. The first individual (Regourdou 1) is represented by a partial skeleton while the second one is represented by a calcaneus. The foot remains of Regourdou 1 have been used in a number of comparative studies, but to date a full description and comparison of all the foot remains from the Regourdou 1 Neandertal, coming from the old excavations and from the recent reanalysis of the faunal remains, does not exist. Here, we describe and comparatively assess the Regourdou 1 tarsals, metatarsals and phalanges. They display traits observed in other Neandertal feet, which are different from some traits of the Sima de los Huesos (Atapuerca) hominins and of Middle Paleolithic, Upper Paleolithic and recent modern humans. These Neandertal features are: a rectangular talar trochlea with a large lateral malleolar facet, a broad talar head, a broad calcaneus with a projecting sustentaculum tali, a wide and wedged navicular with a projecting medial tubercle, large and wide bases of the lateral metatarsals, and mediolaterally expanded and robust phalanges that also show hallux valgus in a strongly built hallux.


Asunto(s)
Pie/anatomía & histología , Fósiles/anatomía & histología , Hombre de Neandertal/anatomía & histología , Animales , Antropología Física , Francia , Masculino
6.
Am J Phys Anthropol ; 169(1): 93-103, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30848485

RESUMEN

OBJECTIVES: Humans generally comply with the ecological rule of Allen (1877), with populations from tropical environments exhibiting body proportions in which limb segments are long relative to trunk height compared to temperate groups. This study tests whether ecogeographic differences in intralimb proportions are identifiable among two modern fetal samples of differing ancestry. MATERIALS AND METHODS: Data are derived from radiographic measurements of long bone diaphyseal length and crown-heel length (CHL) of contemporary, spontaneously aborted fetuses of African Americans ("black") of assumed African (tropical) ancestry and European Americans ("white") of assumed European (temperate) ancestry (n = 184). Population individual limb elements, brachial, and crural indices are compared via analyses of covariance (ANCOVA). Potential patterns of divergent allometric growth are quantified through principal components analysis (PCA). RESULTS: African ancestral distal limb elements were consistently, albeit slightly, longer than those of European ancestry, relative to CHL. None of the ANCOVA interactions with ancestry are statistically significant for limb indices. The radius was the only single element that displayed a statistically significant ancestry effect (p = 0.0435) equating to a 1 mm difference. PCA highlights that upper limbs demonstrate negative allometry and lower limbs demonstrate positive allometry with sample-specific multivariate growth patterns being nearly identical. Differences in growth allometry late in gestation make little contribution to observed differences in adult limb proportions. DISCUSSION: No statistically significant ecogeographic patterns were appreciated among intralimb proportions between these groups during the fetal period. This study contributes to a greater appreciation of phenotypic plasticity, ecogeographic variation in ontogeny, and the evolution of modern human diversity.


Asunto(s)
Feto/anatomía & histología , Extremidad Inferior/anatomía & histología , Extremidad Superior/anatomía & histología , Adaptación Biológica , Antropología Física , Antropometría , Población Negra/estadística & datos numéricos , Huesos/anatomía & histología , Femenino , Geografía , Humanos , Masculino , Población Blanca/estadística & datos numéricos
7.
J Hum Evol ; 130: 151-171, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29496322

RESUMEN

The morphology and size of the Neandertal thorax is a subject of growing interest due to its link to general aspects of body size and shape, including physiological aspects related to bioenergetics and activity budgets. However, the number of well-preserved adult Neandertal costal remains is still low. The recent finding of new additional costal remains from the Regourdou 1 (R1) skeleton has rendered this skeleton as one of the most complete Neandertal costal skeletons with a minimum of 18 ribs represented, five of which are complete or virtually complete. Here we describe for the first time all the rib remains from R1 and compare them to a large modern Euroamerican male sample as well as to other published Neandertal individuals. The costal skeleton of this individual shows significant metric and morphological differences from our modern human male comparative sample. The perceived differences include: dorsoventrally large 1st and 2nd ribs, 3rd ribs with a very closed dorsal curvature and large maximum diameters at the posterior angle, a large tubercle-iliocostal line distance in the 4th rib, thick shafts at the dorsal end of its 6th ribs, thick mid-shafts of the 8th ribs, large articular tubercles at the 9th ribs, and thick shafts of the 11th and 12th ribs. Here we also describe a new mesosternal fragment: the left lateral half of sternebral segments 4 and 5. This portion reveals that the mesosternum of R1 had a sternal foramen in its inferiormost preserved sternal segment and supports previous estimation of the total length of this mesosternum. The new costal remains from R1 support the view that Neandertals, when compared with modern humans, show a significantly different thorax, consistent with differences found in other anatomical regions such as the vertebral column and pelvis.


Asunto(s)
Fósiles/anatomía & histología , Hombre de Neandertal/anatomía & histología , Costillas/anatomía & histología , Animales , Masculino
8.
J Hum Evol ; 111: 119-138, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28874266

RESUMEN

Homo erectus and later humans have enlarged body sizes, reduced sexual dimorphism, elongated lower limbs, and increased encephalization compared to Australopithecus, together suggesting a distinct ecological pattern. The mosaic expression of such features in early Homo, including Homo habilis, Homo rudolfensis, and some early H. erectus, suggests that these traits do not constitute an integrated package. We examined the evidence for body mass, stature, limb proportions, body size and dental size dimorphism, and absolute and relative brain size in Homo naledi as represented in the Dinaledi Chamber sample. H. naledi stature and body mass are low compared to reported values for H. erectus, with the exception of some of the smaller bodied Dmanisi H. erectus specimens, and overlap with larger Australopithecus and early Homo estimates. H. naledi endocranial volumes (465-560 cc) and estimates of encephalization quotient are also similar to Australopithecus and low compared to all Homo specimens, with the exception of Homo floresiensis (LB1) and the smallest Dmanisi H. erectus specimen (D4500). Unlike Australopithecus, but similar to derived members of genus Homo, the Dinaledi assemblage of H. naledi exhibits both low levels of body mass and dental size variation, with an estimated body mass index of sexual dimorphism less than 20%, and appears to have an elongated lower limb. Thus, the H. naledi bauplan combines features not typically seen in Homo species (e.g., small brains and bodies) with those characteristic of H. erectus and more recent Homo species (e.g., reduced mass dimorphism, elongated lower limb).


Asunto(s)
Tamaño Corporal , Encéfalo/anatomía & histología , Fósiles/anatomía & histología , Hominidae/anatomía & histología , Caracteres Sexuales , Animales , Evolución Biológica , Humanos , Húmero/anatomía & histología , Tamaño de los Órganos , Tibia/anatomía & histología , Diente/anatomía & histología
9.
J Hum Evol ; 110: 1-17, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28778459

RESUMEN

The understanding of Neanderthal societies, both with regard to their funerary behaviors and their subsistence activities, is hotly debated. Old excavations and a lack of taphonomic context are often factors that limit our ability to address these questions. To better appreciate the exact nature of what is potentially the oldest burial in Western Europe, Regourdou (Montignac-sur-Vézère, Dordogne), and to better understand the taphonomy of this site excavated more than 50 years ago, we report in this contribution a study of the most abundant animals throughout its stratigraphy: the European rabbit (Oryctolagus cuniculus). In addition to questions surrounding the potential bioturbation of the site's stratigraphy, analysis of the Regourdou rabbits could provide new information on Neandertal subsistence behavior. The mortality profile, skeletal-part representation, breakage patterns, surface modification, and comparison with modern reference collections supports the hypothesis that the Regourdou rabbit remains were primarily accumulated due to natural (attritional) mortality. Radiocarbon dates performed directly on the rabbit remains give ages ranging within the second half of Marine Isotope Stage 3, notably younger than the regional Mousterian period. We posit that rabbits dug their burrows within Regourdou's sedimentological filling, likely inhabiting the site after it was filled. The impact of rabbit activity now brings into question both the reliability of the archaeostratigraphy of the site and the paleoenvironmental reconstructions previously proposed for it, and suggests rabbits may have played a role in the distribution of the Neandertal skeletal remains.


Asunto(s)
Entierro , Fósiles , Hombre de Neandertal , Animales , Europa (Continente) , Conejos , Datación Radiométrica , Reproducibilidad de los Resultados , Factores de Tiempo
10.
J Hum Evol ; 104: 174-204, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27855981

RESUMEN

This paper describes the 108 femoral, patellar, tibial, and fibular elements of a new species of Homo (Homo naledi) discovered in the Dinaledi chamber of the Rising Star cave system in South Africa. Homo naledi possesses a mosaic of primitive, derived, and unique traits functionally indicative of a bipedal hominin adapted for long distance walking and possibly running. Traits shared with australopiths include an anteroposteriorly compressed femoral neck, a mediolaterally compressed tibia, and a relatively circular fibular neck. Traits shared with Homo include a well-marked linea aspera, anteroposteriorly thick patellae, relatively long tibiae, and gracile fibulae with laterally oriented lateral malleoli. Unique features include the presence of two pillars on the superior aspect of the femoral neck and a tubercular distal insertion of the pes anserinus on the tibia. The mosaic morphology of the H. naledi thigh and leg appears most consistent with a species intermediate between Australopithecus spp. and Homo erectus and, accordingly, may offer insight into the nature of the earliest members of genus Homo. These fossils also expand the morphological diversity of the Homo lower limb, perhaps indicative of locomotor diversity in our genus.


Asunto(s)
Fósiles/anatomía & histología , Hominidae/anatomía & histología , Huesos de la Pierna/anatomía & histología , Animales , Evolución Biológica , Sudáfrica
11.
J Hum Evol ; 97: 109-22, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27457549

RESUMEN

Long-term trends in robusticity of lower limb bones in the genus Homo through the Pleistocene until the present have been proposed, which have been interpreted as a consequence of decreasing levels of mobility and activity patterns, changes in lifestyle, and environmental factors. There has also long been evidence that skeletal strength increases over an individual's lifespan. This increase is caused by continuous bone remodeling that optimizes the structure of a bone to resist mechanical loadings and creates a balance between endosteal resorption and subperiosteal apposition. However, none of the previous studies of temporal trends in robusticity has considered both processes and analyzed how individual age-related robusticity might influence higher-level temporal trends. This paper therefore explores temporal trends in robusticity of lower limb long bones within the genus Homo and considers how individual ages-at-death can confound published evolutionary trends, given the fact that some aspects of relative bone strength tend to increase over individual lifespans. Cross-sectional diaphyseal properties of the midshaft and proximal femur and midshaft tibia of Pleistocene and early Holocene individuals, together with data on age-at-death are used to analyze changes in relative bone strength relative to individuals' ages and evolutionary time. The results show increasing bone strength in adulthood until the fourth decade and then a slight decrease, an observation that conforms to previously published results on recent human populations. However, no significant impact of age-at-death on the trends along an evolutionary trajectory has been detected. The evolutionary trends in femoral and tibial relative strength can be described as fluctuating, probably as a consequence of changing mobility patterns, environmentally and technologically influenced behaviors, and demographic processes. The differences between evolutionary trends published in several studies are explained primarily as a result of different ways of standardizing cross-sectional parameters for size, and differences in sample composition.


Asunto(s)
Densidad Ósea , Fémur/fisiología , Hominidae/fisiología , Tibia/fisiología , Adolescente , Adulto , Factores de Edad , Animales , Evolución Biológica , Fenómenos Biomecánicos , Femenino , Fémur/anatomía & histología , Hominidae/anatomía & histología , Humanos , Masculino , Persona de Mediana Edad , Tibia/anatomía & histología , Adulto Joven
12.
Elife ; 42015 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-26354291

RESUMEN

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot and lower limb. These humanlike aspects are contrasted in the postcrania with a more primitive or australopith-like trunk, shoulder, pelvis and proximal femur. Representing at least 15 individuals with most skeletal elements repeated multiple times, this is the largest assemblage of a single species of hominins yet discovered in Africa.


Asunto(s)
Hominidae/anatomía & histología , Hominidae/clasificación , Animales , Antropometría , Humanos , Filogenia , Sudáfrica
13.
Am J Phys Anthropol ; 156(4): 614-24, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25470747

RESUMEN

A new model for estimating human body surface area and body volume/mass from standard skeletal metrics is presented. This model is then tested against both 1) "independently estimated" body surface areas and "independently estimated" body volume/mass (both derived from anthropometric data) and 2) the cylindrical model of Ruff. The model is found to be more accurate in estimating both body surface area and body volume/mass than the cylindrical model, but it is more accurate in estimating body surface area than it is for estimating body volume/mass (as reflected by the standard error of the estimate when "independently estimated" surface area or volume/mass is regressed on estimates derived from the present model). Two practical applications of the model are tested. In the first test, the relative contribution of the limbs versus the trunk to the body's volume and surface area is compared between "heat-adapted" and "cold-adapted" populations. As expected, the "cold-adapted" group has significantly more of its body surface area and volume in its trunk than does the "heat-adapted" group. In the second test, we evaluate the effect of variation in bi-iliac breadth, elongated or foreshortened limbs, and differences in crural index on the body's surface area to volume ratio (SA:V). Results indicate that the effects of bi-iliac breadth on SA:V are substantial, while those of limb lengths and (especially) the crural index are minor, which suggests that factors other than surface area relative to volume are driving morphological variation and ecogeographical patterning in limb prorportions.


Asunto(s)
Antropometría/métodos , Tamaño Corporal/fisiología , Superficie Corporal , Huesos/anatomía & histología , Modelos Biológicos , Modelos Estadísticos , Adulto , Antropología Física , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Adulto Joven
14.
Proc Natl Acad Sci U S A ; 111(12): 4438-42, 2014 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-24616525

RESUMEN

The Late Pleistocene archaic humans from western Eurasia (the Neandertals) have been described for a century as exhibiting absolutely and relatively long clavicles. This aspect of their body proportions has been used to distinguish them from modern humans, invoked to account for other aspects of their anatomy and genetics, used in assessments of their phylogenetic polarities, and used as evidence for Late Pleistocene population relationships. However, it has been unclear whether the usual scaling of Neandertal clavicular lengths to their associated humeral lengths reflects long clavicles, short humeri, or both. Neandertal clavicle lengths, along with those of early modern humans and latitudinally diverse recent humans, were compared with both humeral lengths and estimated body masses (based on femoral head diameters). The Neandertal do have long clavicles relative their humeri, even though they fall within the ranges of variation of early and recent humans. However, when scaled to body masses, their humeral lengths are relatively short, and their clavicular lengths are indistinguishable from those of Late Pleistocene and recent modern humans. The few sufficiently complete Early Pleistocene Homo clavicles seem to have relative lengths also well within recent human variation. Therefore, appropriately scaled clavicular length seems to have varied little through the genus Homo, and it should not be used to account for other aspects of Neandertal biology or their phylogenetic status.


Asunto(s)
Clavícula/anatomía & histología , Hombre de Neandertal , Animales , Femenino , Fósiles
15.
Am J Phys Anthropol ; 152(4): 506-15, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24132859

RESUMEN

Variation in humeral morphology among hominoids has long been recognized in relation to both phylogeny and behavior. Here, we use 3D landmark data to analyze humeral shape among hominoids, including hylobatids (n = 37), Pongo (n = 33), Homo (n = 74), Pan (n = 55), and Gorilla (n = 45) to examine the relative influence of phylogenetic history vs. locomotor adaptation on humeral shape. Principal components analysis (PCA) of Procrustes shape data derived from 19 humeral type II or type III landmarks (Bookstein, 1991) for these taxa reveals the following: PC1, which primarily reflects the humeral torsion (or lack thereof) and relative diaphyseal and epiphyseal breadths, separates the relatively narrow-shafted, small articular dimensions and low humeral torsion Hylobates, and to a lesser extent, Pongo, humeri from those of the African hominoids. PC2, which largely contrasts shafts that are posteriorly convex (high PC2 scores) with antero-posteriorly straight humeral shafts (low PC2 scores) separates Homo, who tend to have A-P straighter shafts, from the more A-P bowed humeral shafts of the apes. These shape patterns suggest that the bowed shafts of Pan, Pongo, and Gorilla (and to a lesser extent, hylobatids) are due to the fact that in each of these taxa, the humerus is a weight-bearing bone, whereas the shafts of Homo are freed from locomotion. More subtle behavioral indicators are also elucidated, whereas cluster analyses (minimum spanning tree fit to a principal coordinates [PCO] plot and UPGMA dendrogram) reveal strong phylogenetic signals in the hominoid humerus as well.


Asunto(s)
Antropometría/métodos , Hominidae/anatomía & histología , Húmero/anatomía & histología , Imagenología Tridimensional/métodos , Análisis de Varianza , Animales , Humanos , Análisis de Componente Principal
16.
Science ; 340(6129): 1233477, 2013 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-23580536

RESUMEN

The evolution of the human upper limb involved a change in function from its use for both locomotion and prehension (as in apes) to a predominantly prehensile and manipulative role. Well-preserved forelimb remains of 1.98-million-year-old Australopithecus sediba from Malapa, South Africa, contribute to our understanding of this evolutionary transition. Whereas other aspects of their postcranial anatomy evince mosaic combinations of primitive (australopith-like) and derived (Homo-like) features, the upper limbs (excluding the hand and wrist) of the Malapa hominins are predominantly primitive and suggest the retention of substantial climbing and suspensory ability. The use of the forelimb primarily for prehension and manipulation appears to arise later, likely with the emergence of Homo erectus.


Asunto(s)
Huesos de la Extremidad Superior/anatomía & histología , Fósiles , Hominidae/anatomía & histología , Hominidae/fisiología , Extremidad Superior/anatomía & histología , Extremidad Superior/fisiología , Animales , Huesos del Brazo/anatomía & histología , Evolución Biológica , Fenómenos Biomecánicos , Huesos de la Extremidad Superior/fisiología , Clavícula/anatomía & histología , Femenino , Humanos , Locomoción , Masculino , Análisis de Componente Principal , Escápula/anatomía & histología , Sudáfrica
17.
Am J Phys Anthropol ; 142(2): 287-302, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19927367

RESUMEN

Given the well-documented fact that human body proportions covary with climate (presumably due to the action of selection), one would expect that the Ipiutak and Tigara Inuit samples from Point Hope, Alaska, would be characterized by an extremely cold-adapted body shape. Comparison of the Point Hope Inuit samples to a large (n > 900) sample of European and European-derived, African and African-derived, and Native American skeletons (including Koniag Inuit from Kodiak Island, Alaska) confirms that the Point Hope Inuit evince a cold-adapted body form, but analyses also reveal some unexpected results. For example, one might suspect that the Point Hope samples would show a more cold-adapted body form than the Koniag, given their more extreme environment, but this is not the case. Additionally, univariate analyses seldom show the Inuit samples to be more cold-adapted in body shape than Europeans, and multivariate cluster analyses that include a myriad of body shape variables such as femoral head diameter, bi-iliac breadth, and limb segment lengths fail to effectively separate the Inuit samples from Europeans. In fact, in terms of body shape, the European and the Inuit samples tend to be cold-adapted and tend to be separated in multivariate space from the more tropically adapted Africans, especially those groups from south of the Sahara.


Asunto(s)
Huesos/anatomía & histología , Fósiles , Inuk , Esqueleto , Alaska , Análisis de Varianza , Antropometría/métodos , Tamaño Corporal , Análisis por Conglomerados , Femenino , Humanos , Masculino , Paleontología , Análisis de Componente Principal
18.
J Hum Evol ; 57(6): 773-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19878967

RESUMEN

In humans, a notch marking the posterior attachment of the lateral meniscus is often visible on the posterior, lateral plateau of the tibia, adjacent to the intercondylar eminence. In theory, the presence or absence of this notch in dry bone can be used to differentiate the fossil remains of Australopithecus from those of the genus Homo. In a small-scale study, however, we found examples of modern human tibiae that appear not to have such a notch. In other cases, the morphology of the surrounding bone made it difficult to determine whether or not the notch was present. Although based on a small sample, this study questions: 1) the theoretical postulate that the lateral meniscal notch can be used to differentiate between hominin taxa, and 2) the practical reliability of determining the absence or presence of the notch in fossil remains.


Asunto(s)
Fósiles , Hominidae/anatomía & histología , Tibia/anatomía & histología , Animales , Hominidae/clasificación , Humanos , Meniscos Tibiales/anatomía & histología
19.
J Hum Evol ; 57(3): 223-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19674770

RESUMEN

Bivariate femoral length allometry in recent humans, Pan, and Gorilla is investigated with special reference to the diminutive Liang Bua (LB) 1 specimen (the holotype of Homo floresiensis) and six early Pleistocene femora referred to the genus Homo. Relative to predicted body mass, Pan and Gorilla femora show strong negative length allometry while recent human femora evince isometry to positive allometry, depending on sample composition and line-fitting technique employed. The allometric trajectories of Pan and Homo show convergence near the small body size range of LB 1, such that LB 1 manifests a low percentage deviation (d(yx) of Smith [1980]) from the Pan allometric trajectory and falls well within the 95% confidence limits around the Pan individuals (but also outside the 95% confidence limits for recent Homo). In contrast, the six early Pleistocene Homo femora, belonging to larger individuals, show much greater d(yx) values from both Pan and Gorilla and fall well above the 95% confidence limits for these taxa. All but one of these Pleistocene Homo specimens falls within the 95% confidence limits of the recent human sample. Similar results are obtained when femoral length is regressed on femoral head diameter in unlogged bivariate space. Regardless of the ultimate taxonomic status of LB 1, these findings are consistent with a prediction made by us (Franciscus and Holliday, 1992) that hominins in the small body size range of A.L. 288-1 ("Lucy"), including members of the genus Homo, will tend to possess short, ape-like lower limbs as a function of body size scaling.


Asunto(s)
Tamaño Corporal , Fémur/anatomía & histología , Fósiles , Hominidae/anatomía & histología , Animales , Antropometría , Femenino , Humanos , Masculino
20.
J Hum Evol ; 43(4): 513-28, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12393006

RESUMEN

The robust diaphyses of Pleistocene hominins are said to indicate higher activity levels in these prehistoric humans than among people today. Thus, it could be argued that the prediction of body mass from fossil lower limb diaphyseal cortical area (CA) using recent human regressions might lead to erroneously high body mass estimates. This study uses three body mass prediction formulae based on the following features: reconstructed femoral 80% (subtrochanteric) CA, femoral head diameter (FH), and bi-iliac breadth and stature (BIB-St) among European Early and Late Upper Paleolithic (EUP and LUP) and recent humans from Africa and Europe. All three methods produce similar body mass estimates for all groups studied, including recent humans. Gleaning behavioral differences from these data is more difficult, as no significant differences in CA were found among the fossil and recent Europeans. It has been suggested that the EUP had less robust diaphyses than their LUP counterparts. However, here this result is only obtained when CA is size-standardized to femoral length(3) (Ruff et al., 1993, Am. J. phys. Anthrop.91, 21-53 Trinkaus et al., 1998, in Neandertals and Modern Humans in Western Asia, pp.391-404, New York: Plenum). This should not be interpreted as evidence for lower activity levels in the EUP, but rather as an artefact of standardization, for as Wolpoff (1999), Am. J. phys. Anthrop.109, 416-423 points out, these standardized variables are extremely sensitive to limb length differences, and the EUP have longer limbs than their LUP counterparts. With this in mind, these data do not support a pattern of behavioral differences between EUP and LUP humans, and therefore more sensitive measures than CA may be required to detect such differences.


Asunto(s)
Índice de Masa Corporal , Hominidae/anatomía & histología , Animales , Antropología Física , Fémur/anatomía & histología , Predicción , Fósiles , Humanos , Locomoción
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