A Female Homo erectus Pelvis from Gona, Ethiopia

Department of Anatomy, Case Western Reserve University School of Medicine, Cleveland, OH 44106-4930, USA.
Science (Impact Factor: 33.61). 12/2008; 322(5904):1089-92. DOI: 10.1126/science.1163592
Source: PubMed


Analyses of the KNM-WT 15000 Homo erectus juvenile male partial skeleton from Kenya concluded that this species had a tall thin body shape due to specialized locomotor and climatic adaptations. Moreover, it was concluded that H. erectus pelves were obstetrically restricted to birthing a small-brained altricial neonate. Here we describe a nearly complete early Pleistocene adult female H. erectus pelvis from the Busidima Formation of Gona, Afar, Ethiopia. This obstetrically capacious pelvis demonstrates that pelvic shape in H. erectus was evolving in response to increasing fetal brain size. This pelvis indicates that neither adaptations to tropical environments nor endurance running were primary selective factors in determining pelvis morphology in H. erectus during the early Pleistocene.

1 Follower
178 Reads
  • Source
    • "Finally, the pubic symphysis UA 466 is one of the very few represented in the entire hominin fossil record (cf. Simpson et al., 2008). It preserves the entire medial face along with portions of the ilio-pubic and ischio-pubic rami and the inferior-medial border of the obturator foramen (Fig. 10G). "
    [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
    • "Much of the debate centers on the analysis of a single fossil: KNM-WT 15000, a juvenile H. erectus skeleton from Nariokotome, Kenya (Walker and Leakey, 1993). Despite this fossil being nearly complete, varying interpretations of age at death, developmental status and Nariokotome's health have complicated reconstructions of normal, adult morphology in this taxon (e.g., Walker and Leakey, 1993; Dean et al., 2001; Latimer and Ohman, 2001; Simpson et al., 2008; Graves et al., 2010; Haeusler et al., 2011; Schiess and Haeusler, 2013). Initial descriptions of KNM-WT 15000 detailed a modern human-like shoulder and torso (Walker and Leakey, 1993). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Powerful, accurate throwing may have been an important mode of early hunting and defense. Previous work has shown that throwing performance is functionally linked to several anatomical shifts in the upper body that occurred during human evolution. The final shift to occur is the inferior reorientation of the shoulder. Fossil scapulae show the earliest evidence of a more inferior glenoid in Homo erectus. However, where the scapula rests on the thorax is uncertain. The relative length of the clavicle, the only skeletal attachment of the scapula to the torso, is quite variable. Depending on which fossils or skeletal measures are used to reconstruct the H. erectus shoulder, either a novel, anteriorly facing shoulder configuration or a modern human-like lateral orientation is possible. These competing hypotheses have led to very different conclusions regarding the throwing ability and hunting behavior of early Homo. Here, we evaluate competing models of H. erectus shoulder morphology and examine how these models relate to throwing performance. To address these questions, we collected skeletal measures from fossil and extant taxa, as well as anthropometric (N = 36) and kinematic (N = 27) data from Daasanach throwers from northwestern Kenya. Our data show that all H. erectus fossil clavicles fall within the normal range of modern human variation. We find that a commonly used metric for normalizing clavicle length, the claviculohumeral ratio, poorly predicts shoulder position on the torso. Furthermore, no significant relationship between clavicle length and any measure of throwing performance was found. These data support reconstructing the H. erectus shoulder as modern human-like, with a laterally facing glenoid, and suggest that the capacity for high speed throwing dates back nearly two million years.
    Journal of Human Evolution 11/2014; 80. DOI:10.1016/j.jhevol.2014.09.004 · 3.73 Impact Factor
  • Source
    • "Interpretation is obviously limited because the subject concerned is probably a young male. It was not until 2008 that a female H. erectus pelvis was discovered in Ethiopia, going by the name BSN49/P27 [14]. This is a pelvis including the sacrum and both os coxae, the likely age of which is about 0.9–1.4 million years. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective: Study of obstetrical mechanics of Australopithecus Lucy, Homo neanderthalensis and Homo erectus relative to modern Homo sapiens and the Catarrhines. Study design: The material comprised a total of 360 pelves: 3 fossil pelves reconstructed using casts (Australopithecus afarensis Lucy or AL 288-1, Homo erectus KNM-WT 15000, H. neanderthalensis or Kebara 2), 305 female modern adult pelves and 52 female Catarrhine pelves (29 gorillas, 18 chimpanzees, 5 orang-utans). All these pelves were reconstructed in order to carry out 11 pelvimetric measurements. Each measurement was carried out twice and by two different operators. Results: The pelvis of Lucy was platypelloid at each pelvic plane. The pelvic inlet of H. neanderthalensis was anteroposteriorly oval whereas the midplane and the outlet were transversely oval. The pelvis of H. erectus was globally round. In modern women, the inlet was transversely oval. The pelvic midplane and outlet were anteroposteriorly oval. In the great apes, the shape of all three pelvic planes was anteroposteriorly oval. The discriminating value of the various pelvimetry measurements place Australopithecus Lucy, H. neanderthalensis Kebara 2, and H. erectus KNM-WT 15000 close to modern humans and less similar to the great apes. Conclusion: Obstetrical mechanics evolved from dystocic delivery with a transverse orientation in Australopithecus to delivery with a modern human-like rotational birth and an increase in the anteroposterior diameters in H. erectus, H. neanderthalensis and modern H. sapiens.
    European Journal of Obstetrics & Gynecology and Reproductive Biology 08/2014; 181C:316-320. DOI:10.1016/j.ejogrb.2014.08.027 · 1.70 Impact Factor
Show more