Body size and body shape in early hominins. Implications of the Gona pelvis. J Hum Evol

Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Journal of Human Evolution (Impact Factor: 3.73). 11/2009; 58(2):166-78. DOI: 10.1016/j.jhevol.2009.10.003
Source: PubMed


Discovery of the first complete Early Pleistocene hominin pelvis, Gona BSN49/P27, attributed to Homo erectus, raises a number of issues regarding early hominin body size and shape variation. Here, acetabular breadth, femoral head breadth, and body mass calculated from femoral head breadth are compared in 37 early hominin (6.0-0.26 Ma) specimens, including BSN49/P27. Acetabular and estimated femoral head sizes in the Gona specimen fall close to the means for non-Homo specimens (Orrorin tugenesis, Australopithecus africanus, Paranthropus robustus), and well below the ranges of all previously described Early and Middle Pleistocene Homo specimens. The Gona specimen has an estimated body mass of 33.2kg, close to the mean for the non-Homo sample (34.1kg, range 24-51.5kg, n=19) and far outside the range for any previously known Homo specimen (mean=70.5kg; range 52-82kg, n=17). Inclusion of the Gona specimen within H. erectus increases inferred sexual dimorphism in body mass in this taxon to a level greater than that observed here for any other hominin taxon, and increases variation in body mass within H. erectus females to a level much greater than that observed for any living primate species. This raises questions regarding the taxonomic attribution of the Gona specimen. When considered within the context of overall variation in body breadth among early hominins, the mediolaterally very wide Gona pelvis fits within the distribution of other lower latitude Early and Middle Pleistocene specimens, and below that of higher latitude specimens. Thus, ecogeographic variation in body breadth was present among earlier hominins as it is in living humans. The increased M-L pelvic breadth in all earlier hominins relative to modern humans is related to an increase in ellipticity of the birth canal, possibly as a result of a non-rotational birth mechanism that was common to both australopithecines and archaic Homo.

35 Reads
  • Source
    • "Yet, it has an intermediate greater sciatic notch between the latter and the Early Pleistocene KNM-ER 3228 os coxae from East Turkana, likely a male (Rose, 1984). Based on its estimated acetabular diameter (>55 mm), the body mass of the individual represented by UA 173e405 exceeds 65 kg, near the estimates of OH 28 (72.3 kg) and KNM-ER 3228 (67.1 kg) (Ruff, 2010). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The Early to Middle Pleistocene continental transition in East Africa is widely documented from lacustrine and deep-sea records, although significant insights are also provided by fluvio-lacustrine successions of the central and southern African Rift Valley, such as the at Olduvai Gorge succession (Tanzania), the Bouri Formation (Ethiopia) and the Olorgesailie Formation (Kenya). The Early to Middle Pleistocene Dandiero Basin fill (Eritrean Danakil) represents the only continental succession in the northernmost sector of the African Rift Valley that provided abundant fossil vertebrates, including human remains. The present study integrates already available data with new sedimentological, pedological, magnetostratigraphic, paleontological and paleoanthropological investigations of the 300. m thick Aalat section (North Dandiero Basin). This sedimentary succession records repeated shifts from fluvial to lacustrine depositional settings, which occurred under the tight interaction between local tectonics and Pleistocene climate changes. Accumulation was associated with axial sedimentation in a NS-trending extensional basin, with an overall tectono-sedimentary setting comparable with that of the coeval Bouri Formation (Ethiopia). Because of the high rates of sedimentation, a poor to moderate degree of soil development characterizes the whole succession. Sporadic soil horizons testify to carbonate dissolution, leaching and accumulation in calcic and petrocalcic horizons (indicating an overall dry climate). The alternate with local to extensive iron-oxide/hydroxide segregation, promoted by water infiltration under varying drainage conditions and/or seasonal contrast, that record more humid conditions. Magnetostratigraphic dating and correlation indicates that this section is among the world's thickest record embracing the Early-Middle Pleistocene transition, spanning from the Jaramillo to the base of Brunhes chron. The terrestrial vertebrate fauna includes a typical Early to Middle Pleistocene East African mammalian assemblage for this age and is dominated by taxa characterized by strong water dependence. The ichthyofauna, with its abundant Clariidae, is also consistent with the shallow water, fluvio-lacustrine paleobiotopes. The cranial, dental and postcranial human remains from the lower part of the Aalat succession add valuable evidence about the patterns of variation and evolutionary dynamics in African Homo erectus/ergaster near the end of the Early Pleistocene.
    Journal of African Earth Sciences 09/2015; 112. DOI:10.1016/j.jafrearsci.2015.09.012 · 1.40 Impact Factor
  • Source
    • "studies on other hindlimb joint surfaces (e.g., Jungers, 1988). Other research on primate pelvic scaling has focused on the influences of obstetrical requirements and neonatal brain size on pelvic shape (Leutenegger, 1974, 1982; Tague, 2005) especially in relation to the evolution of bipedality and relatively large brain size in early hominin species (Reynolds, 1931; Dart, 1949; Le Gros Clark, 1955; Day, 1973; Lovejoy et al., 1973; Brain et al., 1974; McHenry, 1975; Ashton et al., 1981; Berge, 1984; Berge and Kazmierczak, 1986; Rak and Arensburg, 1987; Berge, 1991; Rak, 1991; Fleagle and Anapol, 1992; Rosenberg, 1992; Berge, 1994; Ruff, 1995; MacLatchy, 1996; Macchiarelli et al., 1999; Marchal, 2000; Haeusler, 2002; Lovejoy, 2005; Lovejoy et al., 2009; Weaver and Hublin, 2009; Ruff, 2010). Research on the obstetrical functions of the pelvis has demonstrated that aspects of the bony birth canal—dimensions of the pelvic inlet, midplane, and outlet—differ intra-and interspecifically, with selection favoring females with larger pelvic diameters in species that have large neonates relative to maternal size (Schultz, 1949; Black, 1970; Leutenegger, 1974). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Identification of positional behavior adaptation in the pelvis of primates is complicated by possible confounding effects of body size and phylogeny. Previous work on primate pelvic allometry has focused primarily on sexual dimorphism and its relationship to obstetric constraints in species with large fetal size relative to maternal size. This study investigates patterns of pelvic scaling with a specific aim to understand how pelvic scaling relates to locomotor function. Patterns of scaling of nine pelvic dimensions were examined in a broad comparative sample of 40 species of primates, covering both haplorhines and strepsirrhines, while accounting for phylogenetic nonindependence. Phylogenetic reduced major axis regressions on pelvic scaling patterns suggest that primate-wide patterns are reflected in haplorhine- and strepsirrhine-specific analyses. Many measures scale isometrically with pelvis size, but notably, features of the ilium tend to scale allometrically. As predicted, ilium width and lower ilium cross-sectional area scale with positive allometry, while lower iliac height scales with negative allometry. Further regression analyses by locomotor group suggest that these ilium measures, as well as pubic symphysis and ischium lengths, differ in their scaling patterns according to locomotor mode. These results suggest that scaling differences within primates, when present, are related to functional differences in locomotor behavior and mechanics. This study supports recent work that identifies adaptations to locomotor loading in the ilium and highlights the need for a better understanding of the relationship between pelvic structural mechanics and the mechanical requirements of primate locomotion. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
    American Journal of Physical Anthropology 02/2015; 156(4). DOI:10.1002/ajpa.22696 · 2.38 Impact Factor
  • Source
    • "They are a core element for assessing body proportions (Carretero et al., 2012; Holliday, 1997a; Trinkaus et al., 2014). Body size estimates also permit assessments of sexual dimorphism, for those specimens with sexually diagnostic pelvic remains (Plavcan, 2001; Ruff, 2010; Trinkaus, 1980). For these reasons, it is desirable to maximize the available sample sizes for the estimation of body mass among the Pleistocene humans. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Le diamètre de la tête fémorale de Regourdou 1 a été estimé à partir des dimensions de la portion ischiatique de l’acétabulum. Cette mesure permet d’estimer certaines variables corporelles et apporte ainsi de nouvelles données sur la taille et les proportions corporelles des hommes du Pléistocène supérieur. L’estimation de ce diamètre s’est faite en deux étapes. Dans un premier temps, une sphère a été virtuellement conformée sur la surface 3D de l’acétabulum ischiatique. Dans un second temps, le diamètre de la tête fémorale a été estimé à partir du diamètre de la sphère acétabulaire grâce à une formule de régression calculée sur un échantillon de référence moderne. La moyenne des résultats obtenus, comme l’étendue des valeurs, place Regourdou 1 parmi les plus petits Néandertaliens (Europe et Asie du Sud-Ouest confondus), bien que cet individu présente une longueur humérale supérieure à la moyenne de ce même échantillon. Ces caractéristiques permettent de rapprocher Regourdou 1 de Kebara 2, ces deux individus présentant des bras relativement longs par rapport à la taille du corps. Ces nouvelles données sont ainsi l’occasion d’enrichir la variation des proportions corporelles chez les Néandertaliens.
    Comptes Rendus Palevol 11/2014; 13(8). DOI:10.1016/j.crpv.2014.07.003 · 1.19 Impact Factor
Show more