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Torres-Tamayo N, Rae TC, Hirasaki E, Betti L. Testing the reliability of the rearticulation of osteological primate pelves in comparative morphological studies. Anat Rec (Hoboken) 2024; 307:2816-2833. [PMID: 38112056 DOI: 10.1002/ar.25366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/24/2023] [Accepted: 11/27/2023] [Indexed: 12/20/2023]
Abstract
The evolution of human pelvic form is primarily studied using disarticulated osteological material of living and fossil primates that need rearticulation to approximate anatomical position. To test whether this technique introduces errors that impact biological signals, virtual rearticulations of the pelvis in anatomical position from computed tomography scans were compared with rearticulated models from the same individuals for one female and one male of Homo sapiens, Pan troglodytes, Macaca mulatta, Lepilemur mustelinus, Galago senegalensis, and Nycticebus pygmaeus. "Cadaveric" pelvic bones were first analyzed in anatomical position, then the three bones were segmented individually, intentionally scattered, and "rearticulated" to test for rearticulation error. Three-dimensional landmarks and linear measurements were used to characterize the overall pelvis shape. Cadaveric and rearticulated pelves were not identical, but inter-specific and intra-specific shape differences were higher than the landmarking error in the cadaveric individuals and the landmarking/rearticulation error in the rearticulated pelves, demonstrating that the biological signal is stronger than the noise introduced by landmarking and rearticulation. The rearticulation process, however, underestimates the medio-lateral pelvic measurements in species with a substantial pubic gap (e.g., G. senegalensis, N. pygmaeus) possibly because the greater contribution of soft tissue to the pelvic girdle introduces higher uncertainty during rearticulation. Nevertheless, this discrepancy affects only the caudal-most part of the pelvis. This study demonstrates that the rearticulation of pelvic bones does not substantially affect the biological signal in comparative 3D morphological studies but suggests that anatomically connected pelves of species with wide pubic gaps should be preferentially included in these studies.
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Affiliation(s)
| | - Todd C Rae
- School of Life Sciences, University of Sussex, Brighton, UK
| | - Eishi Hirasaki
- Centre for Evolutionary Origins of Human Behavior, Kyoto University, Inuyama, Japan
| | - Lia Betti
- Department of Anthropology, University College London, London, UK
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Pietsch H, Cristino D, Danelson K, Bolte J, Mason M, Kemper A, Cavanaugh J, Hardy W. Comparison of Adult Female and Male PMHS Pelvis and Lumbar Response to Underbody Blast. STAPP CAR CRASH JOURNAL 2024; 67:44-77. [PMID: 38662621 DOI: 10.4271/2023-22-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
The goal of this study was to gather and compare kinematic response and injury data on both female and male whole-body Post-mortem Human Surrogates (PMHS) responses to Underbody Blast (UBB) loading. Midsized males (50th percentile, MM) have historically been most used in biomechanical testing and were the focus of the Warrior Injury Assessment Manikin (WIAMan) program, thus this population subgroup was selected to be the baseline for female comparison. Both small female (5th percentile, SF) and large female (75th percentile, LF) PMHS were included in the test series to attempt to discern whether differences between male and female responses were predominantly driven by sex or size. Eleven tests, using 20 whole-body PMHS, were conducted by the research team. Preparation of the rig and execution of the tests took place at the Aberdeen Proving Grounds (APG) in Aberdeen, MD. Two PMHS were used in each test. The Accelerative Loading Fixture (ALF) version 2, located at APG's Bear Point range was used for all male and female whole-body tests in this series. The ALF was an outdoor test rig that was driven by a buried explosive charge, to accelerate a platform holding two symmetrically mounted seats. The platform was designed as a large, rigid frame with a deformable center section that could be tuned to simulate the floor deformation of a vehicle during a UBB event. PMHS were restrained with a 5-point harness, common in military vehicle seats. Six-degree-of-freedom motion blocks were fixed to L3, the sacrum, and the left and right iliac wings. A three-degree-of freedom block was fixed to T12. Strain gages were placed on L4 and multiple locations on the pelvis. Accelerometers on the floor and seat of the ALF provided input data for each PMHS' feet and pelvis. Time histories and mean peak responses in z-axis acceleration were similar among the three PMHS groups in this body region. Injury outcomes were different and seemed to be influenced by both sex and size contributions. Small females incurred pelvis injuries in absence of lumbar injures. Midsized males had lumbar vertebral body fractures without pelvis injuries. And large females with injuries had both pelvis and lumbar VB fractures. This study provides evidence supporting the need for female biomechanical testing to generate female response and injury thresholds. Without the inclusion of female PMHS, the differences in the injury patterns between the small female and midsized male groups would not have been recognized. Standard scaling methods assume equivalent injury patterns between the experimental and scaled data. In this study, small female damage occurred in a different anatomical structure than for the midsized males. This is an important discovery for the development of anthropomorphic test devices, injury criteria, and injury mitigating technologies. The clear separation of small female damage results, in combination with seat speeds, suggest that the small female pelvis injury threshold in UBB events lies between 4 - 5 m/s seat speed. No inference can be made about the small female lumbar threshold, other than it is likely at higher speeds and/or over longer duration. Male lumbar spine damage occurred in both the higher- and lower lower-rate tests, indicating the injury threshold would be below the seat pulses tested in these experiments. Large females exhibited injury patterns that reflected both the small female and midsized male groups - with damaged PMHS having fractures in both pelvis and lumbar, and in both higher- and lower- rate tests. The difference in damage patterns between the sex and size groups should be considered in the development of injury mitigation strategies to protect across the full population.
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Affiliation(s)
- Hollie Pietsch
- US Army DEVCOM Ground Vehicle Systems Center, Wayne State University
| | | | - Kerry Danelson
- Wake Forest School of Medicine, Department of Orthopedic Surgery
| | | | | | | | - John Cavanaugh
- Wayne State University, Department of Biomedical Engineering (Retired)
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Bugeja JM, Xia Y, Chandra SS, Murphy NJ, Crozier S, Hunter DJ, Fripp J, Engstrom C. Analysis of cam location characteristics in FAI syndrome patients from 3D MR images demonstrates sex-specific differences. J Orthop Res 2024; 42:385-394. [PMID: 37525546 DOI: 10.1002/jor.25674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 06/22/2023] [Accepted: 07/26/2023] [Indexed: 08/02/2023]
Abstract
Cam femoroacetabular impingement (FAI) syndrome is associated with hip osteoarthritis (OA) development. Hip shape features, derived from statistical shape modeling (SSM), are predictive for OA incidence, progression, and arthroplasty. Currently, no three-dimensional (3D) SSM studies have investigated whether there are cam shape differences between male and female patients, which may be of potential clinical relevance for FAI syndrome assessments. This study analyzed sex-specific cam location and shape in FAI syndrome patients from clinical magnetic resonance examinations (M:F 56:41, age: 16-63 years) using 3D focused shape modeling-based segmentation (CamMorph) and partial least squares regression to obtain shape features (latent variables [LVs]) of cam morphology. Two-way analysis of variance tests were used to assess cam LV data for sex and cam volume severity differences. There was no significant interaction between sex and cam volume severity for the LV data. A sex main effect was significant for LV 1 (cam size) and LV 2 (cam location) with medium to large effect sizes (p < 0.001, d > 0.75). Mean results revealed males presented with a superior-focused cam, whereas females presented with an anterior-focused cam. When stratified by cam volume, cam morphologies were located superiorly in male and anteriorly in female FAI syndrome patients with negligible, mild, or moderate cam volumes. Both male and female FAI syndrome patients with major cam volumes had a global cam distribution. In conclusion, sex-specific cam location differences are present in FAI syndrome patients with negligible, mild, and moderate cam volumes, whereas major cam volumes were globally distributed in both male and female patients.
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Affiliation(s)
- Jessica M Bugeja
- Australian e-Health Research Centre, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Brisbane, QLD, Australia
| | - Ying Xia
- Australian e-Health Research Centre, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Brisbane, QLD, Australia
| | - Shekhar S Chandra
- School of Information Technology and Electrical Engineering, Faculty of Engineering, Architecture and Information Technology, The University of Queensland, Brisbane, QLD, Australia
| | - Nicholas J Murphy
- Kolling Institute of Medical Research, Sydney Musculoskeletal Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
- Department of Orthopaedic Surgery, John Hunter Hospital, Newcastle, NSW, Australia
| | - Stuart Crozier
- School of Information Technology and Electrical Engineering, Faculty of Engineering, Architecture and Information Technology, The University of Queensland, Brisbane, QLD, Australia
| | - David J Hunter
- Kolling Institute of Medical Research, Sydney Musculoskeletal Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
- Department of Rheumatology, Royal North Shore Hospital, St Leonards, NSW, Australia
| | - Jurgen Fripp
- Australian e-Health Research Centre, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Brisbane, QLD, Australia
| | - Craig Engstrom
- School of Human Movement and Nutrition Sciences, Faculty of Health and Behavioural Sciences, The University of Queensland, Brisbane, QLD, Australia
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Wall-Scheffler C, Kurki H. Beyond sex, gender, and other dilemmas: Human pelvic morphology from an integrative context. Evol Anthropol 2023; 32:293-305. [PMID: 37609957 DOI: 10.1002/evan.22001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 05/30/2023] [Accepted: 08/01/2023] [Indexed: 08/24/2023]
Abstract
Recent research on the pelvis has clarified the flexibility of pelvic bones to manage nearly infinite possibilities in terms of selection and drift, while still maintaining excellent bipedalism. Despite this work, and the studies outlining the diversity of pelvic morphology across the hominin lineage, conversations continue to be stymied by distractions related to purported trade-offs that the different functions the pelvis must either allow for (e.g., parturition) or directly perform (e.g., attachment sites of muscles). Here we show that tight constraints on morphology are not evident in the pelvic variation of multiple human populations. We thus provide further evidence that human pelves are not geometrically similar and that pelvic morphology successfully balances the intersection of population history, active selective, and drift.
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Affiliation(s)
- Cara Wall-Scheffler
- Department of Biology, Seattle Pacific University, Seattle, Washington, USA
- Department of Anthropology, University of Washington, Seattle, Washington, USA
| | - Helen Kurki
- Department of Anthropology, University of Victoria, Victoria, British Columbia, Canada
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Warrener A. The multifactor pelvis: An alternative to the adaptationist approach of the obstetrical dilemma. Evol Anthropol 2023; 32:260-274. [PMID: 37527355 DOI: 10.1002/evan.21997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 02/23/2023] [Accepted: 07/08/2023] [Indexed: 08/03/2023]
Abstract
The obstetrical dilemma describes the competing demands that a bipedally adapted pelvis and a large-brained neonate place on human childbirth and is the predominant model within which hypotheses about the evolution of the pelvis are framed. I argue the obstetrical dilemma follows the adaptationist program outlined by Gould and Lewontin in 1979 and should be replaced with a new model, the multifactor pelvis. This change will allow thorough consideration of nonadaptive explanations for the evolution of the human pelvis and avoid negative social impacts from considering human childbirth inherently dangerous. First, the atomization of the pelvis into discrete traits is discussed, after which current evidence for both adaptive and nonadaptive hypotheses is evaluated, including childbirth, locomotion, shared genetics with other traits under selection, evolutionary history, genetic drift, and environmental and epigenetic influences on the pelvis.
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Affiliation(s)
- Anna Warrener
- Department of Anthropology, University of Colorado Denver, Denver, Colorado, USA
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Grunstra NDS, Betti L, Fischer B, Haeusler M, Pavlicev M, Stansfield E, Trevathan W, Webb NM, Wells JCK, Rosenberg KR, Mitteroecker P. There is an obstetrical dilemma: Misconceptions about the evolution of human childbirth and pelvic form. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 181:535-544. [PMID: 37353889 PMCID: PMC10952510 DOI: 10.1002/ajpa.24802] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 05/27/2023] [Accepted: 06/11/2023] [Indexed: 06/25/2023]
Abstract
Compared to other primates, modern humans face high rates of maternal and neonatal morbidity and mortality during childbirth. Since the early 20th century, this "difficulty" of human parturition has prompted numerous evolutionary explanations, typically assuming antagonistic selective forces acting on maternal and fetal traits, which has been termed the "obstetrical dilemma." Recently, there has been a growing tendency among some anthropologists to question the difficulty of human childbirth and its evolutionary origin in an antagonistic selective regime. Partly, this stems from the motivation to combat increasing pathologization and overmedicalization of childbirth in industrialized countries. Some authors have argued that there is no obstetrical dilemma at all, and that the difficulty of childbirth mainly results from modern lifestyles and inappropriate and patriarchal obstetric practices. The failure of some studies to identify biomechanical and metabolic constraints on pelvic dimensions is sometimes interpreted as empirical support for discarding an obstetrical dilemma. Here we explain why these points are important but do not invalidate evolutionary explanations of human childbirth. We present robust empirical evidence and solid evolutionary theory supporting an obstetrical dilemma, yet one that is much more complex than originally conceived in the 20th century. We argue that evolutionary research does not hinder appropriate midwifery and obstetric care, nor does it promote negative views of female bodies. Understanding the evolutionary entanglement of biological and sociocultural factors underlying human childbirth can help us to understand individual variation in the risk factors of obstructed labor, and thus can contribute to more individualized maternal care.
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Affiliation(s)
- N. D. S. Grunstra
- Department of Evolutionary Biology, Unit for Theoretical BiologyUniversity of ViennaViennaAustria
- Mammal CollectionNatural History Museum ViennaViennaAustria
| | - L. Betti
- School of Life and Health SciencesUniversity of RoehamptonLondonUK
| | - B. Fischer
- Department of Evolutionary Biology, Unit for Theoretical BiologyUniversity of ViennaViennaAustria
| | - M. Haeusler
- Institute of Evolutionary MedicineUniversity of ZurichZurichSwitzerland
| | - M. Pavlicev
- Department of Evolutionary Biology, Unit for Theoretical BiologyUniversity of ViennaViennaAustria
| | - E. Stansfield
- Department of Evolutionary Biology, Unit for Theoretical BiologyUniversity of ViennaViennaAustria
| | - W. Trevathan
- School for Advanced ResearchSanta FeNew MexicoUSA
| | - N. M. Webb
- Institute of Evolutionary MedicineUniversity of ZurichZurichSwitzerland
- Institute of Archaeological Sciences, Senckenberg Centre for Human Evolution and PalaeoenvironmentEberhard‐Karls University of TübingenTübingenGermany
| | - J. C. K. Wells
- UCL Great Ormond Street Institute of Child Health, Population, Policy and Practice Research and Teaching ProgrammeChildhood Nutrition Research CentreLondonUK
| | - K. R. Rosenberg
- Department of AnthropologyUniversity of DelawareNewarkDelawareUSA
| | - P. Mitteroecker
- Department of Evolutionary Biology, Unit for Theoretical BiologyUniversity of ViennaViennaAustria
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De La Paz JS, Buckley HR, Halcrow SE, Techataweewan N, Woodley SJ. Architecture of head and neck soft tissues and associated entheses: An exploration of sexual dimorphism in, and population differences between, New Zealand and Thai individuals. J Anat 2023; 243:110-127. [PMID: 36882366 PMCID: PMC10273350 DOI: 10.1111/joa.13853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 01/24/2023] [Accepted: 02/14/2023] [Indexed: 03/09/2023] Open
Abstract
Understanding the musculoskeletal anatomy of soft tissues of the head and neck is important for surgical applications, biomechanical modelling and management of injuries, such as whiplash. Additionally, analysing sex and population differences in cervical anatomy can inform how biological sex and population variation may impact these anatomical applications. Although some muscles of the head and neck are well-studied, there is limited architectural information that also analyses sex and population variation, for many small cervical soft tissues (muscles and ligaments) and associated entheses (soft tissue attachment sites). Therefore, the aim of this study was to present architectural data (e.g., proximal and distal attachment sites, muscle physiological cross-sectional area, ligament mass, enthesis area) and analyse sex and population differences in soft tissues and entheses associated with sexually dimorphic landmarks on the cranium (nuchal crest and mastoid process) and clavicle (rhomboid fossa). Through the dissection and three-dimensional analysis of 20 donated cadavers from New Zealand (five males, five females; mean age 83 ± 8 years; range 67-93 years) and Thailand (five males, five females; 69 ± 13 years; range 44-87 years), the following soft tissues and their associated entheses were analysed: upper trapezius, semispinalis capitis and the nuchal ligament (nuchal crest); sternocleidomastoid, splenius capitis and longissimus capitis (mastoid process); the clavicular head of pectoralis major, subclavius, sternohyoid and the costoclavicular (rhomboid) ligament (rhomboid fossa). Findings indicate that although muscle, ligament and enthesis sizes were generally similar to previously published data, muscle size was smaller for six of the eight muscles in this study, with only the upper trapezius and subclavius demonstrating similar values to previous studies. Proximal and distal attachment sites were largely consistent with the current research. However, some individuals (six of 20) had proximal upper trapezius attachments on the cranium, with most attaching solely to the nuchal ligament, contrasting with existing literature, which often describes attachment to the occipital bone. With respect to sexual dimorphism, the Thai sample exhibited more sex differences in muscle size than the New Zealand sample, but for enthesis size (area), both samples had the same amount of statistically significant sex differences (5 of 10). Additionally, some significant population differences were found when comparing muscle and enthesis size data between the New Zealand and Thai samples. Despite these findings, no sex or population differences were found for ligament size (mass) in either group. This paper presents new architectural data for several understudied areas of the head and neck, as well as providing analyses on sex and population differences, two areas that have limited representation in anatomy.
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Affiliation(s)
- Jade S. De La Paz
- Department of Anatomy, School of Biomedical SciencesUniversity of OtagoDunedinNew Zealand
| | - Hallie R. Buckley
- Department of Anatomy, School of Biomedical SciencesUniversity of OtagoDunedinNew Zealand
| | - Siân E. Halcrow
- Department of Anatomy, School of Biomedical SciencesUniversity of OtagoDunedinNew Zealand
| | | | - Stephanie J. Woodley
- Department of Anatomy, School of Biomedical SciencesUniversity of OtagoDunedinNew Zealand
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Adegboyega MT, Jhanjar S, Grote MN, Weaver TD. Predicting the shape, size, and placement of adult human pubic symphyses. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 181:182-194. [PMID: 36939148 DOI: 10.1002/ajpa.24725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 02/03/2023] [Accepted: 02/27/2023] [Indexed: 05/18/2023]
Abstract
OBJECTIVES When reconstructing fossil pelves, the articulation of the pelvic bones largely relies on subjective decisions by researchers. Different positionings at the pubic symphysis can affect the overall morphology of the pelvis and the subsequent biological interpretation associated with that individual or species. This study aims to reduce this subjectivity using quantitative models to predict pubic symphysis morphology. METHODS We collected 3D landmarks and semilandmarks on the pubic symphysis and adjacent aspects on the CT scans of 103 adults. Using geometric morphometrics we, (1) quantified pubic symphysis morphology, (2) trained simple and two-stage least-squares linear regression models to predict pubic symphysis shape, and (3) assessed the shape variation in the sample. The model with the lowest prediction error was identified as the best model. Principal components analysis was used to explore the effects of each variable on shape and hypothetical shapes were generated from the model to illustrate these effects. RESULTS The best model is a two-stage least-squares model that predicts pubic symphysis size at the first stage using additive effects of sex and age, then subsequently interacts pubic symphysis size with sex and age at the second stage to predict pubic symphysis shape. Other models with low prediction errors included variables reflecting pelvic size and breadth. CONCLUSION Linear regression modeling can be used to systematically predict pubic symphysis morphology. This method can be used in addition to other techniques to improve fossil reconstructions by more accurately estimating the morphology of this region of the pelvis.
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Affiliation(s)
- Mayowa T Adegboyega
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina, USA
- Department of Anthropology, University of California, Davis, California, USA
| | - Sara Jhanjar
- Department of Anthropology, University of California, Davis, California, USA
- College of Osteopathic Medicine, California Health Sciences University, Clovis, California, USA
| | - Mark N Grote
- Department of Anthropology, University of California, Davis, California, USA
| | - Timothy D Weaver
- Department of Anthropology, University of California, Davis, California, USA
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Lukacs JR. Sexual dimorphism in deciduous tooth crown size: Variability within and between groups. Am J Hum Biol 2022; 34:e23793. [PMID: 36054733 DOI: 10.1002/ajhb.23793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 01/25/2023] Open
Abstract
OBJECTIVES Sexual dimorphism in deciduous tooth crown size is often used to identify sex in sub-adults from archeological sites and forensic settings. Yet sexual dimorphism in deciduous dental attributes is less well documented than in permanent teeth. This analysis was conducted to document variation in sexual dimorphism within and between a global sample of populations. METHODS Mean deciduous tooth crown size was culled from published literature, yielding a sample of 37 groups. Mean mesiodistal (MD) and buccolingual (BL) crown dimensions are the basis for computing percent sexual dimorphism [(M/F-1) * 100]. Three analyses were conducted: (1) a statistical analysis of mean % sex dimorphism (%SD) within and between populations, (2) an evaluation of rank-ordered %SD by tooth, and (3) an assessment of intergroup patterns in degree of sexual dimorphism. Univariate tests of significance, correlation and regression, and multivariate cluster analysis were used. RESULTS Mean %SD is low overall (1.77) for 26 groups and the level of dimorphism is not significantly different for MD (1.68) and BL (1.72) dimensions. The most sexual dimorphic deciduous teeth include incisor, canine and molar tooth types, while in the permanent dentition canines are consistently most sexual dimorphic. Global variation in sexual dimorphism of deciduous tooth size is low with little inter-ethnic variation. CONCLUSIONS Sexual dimorphism in crown size is lower and more variably expressed than in permanent teeth. Differences may relate to developmental, chromosomal, and hormonal factors. Degree of sexual dimorphism is not associated with ethnicity in this global sample.
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Affiliation(s)
- John R Lukacs
- Department of Anthropology, University of Oregon, Eugene, Oregon, USA
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10
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Two Late Pleistocene human femora from Trinil, Indonesia: Implications for body size and behavior in Southeast Asia. J Hum Evol 2022; 172:103252. [PMID: 36162353 DOI: 10.1016/j.jhevol.2022.103252] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/15/2022] [Accepted: 08/15/2022] [Indexed: 11/23/2022]
Abstract
Late Pleistocene hominin postcranial specimens from Southeast Asia are relatively rare. Here we describe and place into temporal and geographic context two partial femora from the site of Trinil, Indonesia, which are dated stratigraphically and via Uranium-series direct dating to ca. 37-32 ka. The specimens, designated Trinil 9 and 10, include most of the diaphysis, with Trinil 9 being much better preserved. Microcomputed tomography is used to determine cross-sectional diaphyseal properties, with an emphasis on midshaft anteroposterior to mediolateral bending rigidity (Ix/Iy), which has been shown to relate to both body shape and activity level in modern humans. The body mass of Trinil 9 is estimated from cortical area and reconstructed length using new equations based on a Pleistocene reference sample. Comparisons are carried out with a large sample of Pleistocene and Holocene East Asian, African, and European/West Asian femora. Our results show that Trinil 9 has a high Ix/Iy ratio, most consistent with a relatively narrow-bodied male from a mobile hunting-gathering population. It has an estimated body mass of 55.4 kg and a stature of 156 cm, which are small relative to Late Pleistocene males worldwide, but larger than the penecontemporaneous Deep Skull femur from Niah Cave, Malaysia, which is very likely female. This suggests the presence of small-bodied active hunter-gatherers in Southeast Asia during the later Late Pleistocene. Trinil 9 also contrasts strongly in morphology with earlier partial femora from Trinil dating to the late Early-early Middle Pleistocene (Femora II-V), and to a lesser extent with the well-known complete Femur I, most likely dating to the terminal Middle-early Late Pleistocene. Temporal changes in morphology among femoral specimens from Trinil parallel those observed in Homo throughout the Old World during the Pleistocene and document these differences within a single site.
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11
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Smith AH, Brassett C, Gooding C, Abood A, Norrish A. Vastus lateralis vs rectus femoris muscle flaps for recalcitrant hip joint infection: an anatomical study comparing the effectiveness of acetabular dead space control. Clin Anat 2022; 35:961-973. [PMID: 35736665 PMCID: PMC9544425 DOI: 10.1002/ca.23925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 05/08/2022] [Accepted: 06/22/2022] [Indexed: 11/09/2022]
Abstract
Eliminating recalcitrant prosthetic hip joint infections remains one of the greatest challenges in orthopedic surgery. In such cases, the salvage procedure of femoral head excision (the Girdlestone procedure) is often performed. There has been emerging surgical interest in filling the resulting acetabular dead space with a pedicled muscle flap, to enable antibiotic delivery. Both vastus lateralis (VL) and rectus femoris (RF) muscle flaps have been described for this purpose with good success. This study is the first anatomical investigation comparing VL and RF as candidates for interposition myoplasty following hip joint excision. Following standard surgical technique, the Girdlestone procedure and interposition myoplasty of both RF and VL were performed on 10 cadavers. The primary aim was to determine which muscle flap eliminated a greater volume of acetabular dead space. Secondary aims were to characterize the blood supply to RF and assess additional metrics indicative of the likelihood of flap success. The VL flap eliminated more dead space than RF. However, the use of the RF flap was feasible in all cases and has several benefits, including ease of harvest, mobility, and aesthetics. The location of the inferior vascular pedicle into RF was relatively consistent and the most effective predictor of flap success. Both VL and RF are effective in reducing acetabular dead space. While VL can fill a greater volume, the RF flap has technical advantages, related to the predictability of the blood supply.
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Affiliation(s)
- Alexandria H Smith
- Human Anatomy Centre, Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge
| | - Cecilia Brassett
- Human Anatomy Centre, Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge
| | | | - Ahid Abood
- Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge
| | - Alan Norrish
- Academic Orthopaedics, Trauma and Sports Medicine, University of Nottingham, Queen's Medical Centre, Nottingham
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12
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Holmes L, Watts-Overall TM, Slettevold E, Gruia DC, Rieger G. Sex Differences in Sexual Arousal and Finger Length Ratio. JOURNAL OF SEX RESEARCH 2022; 59:515-523. [PMID: 33522850 DOI: 10.1080/00224499.2021.1874262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Most men show sexual arousal to one, preferred sex, whereas most women respond to both sexes, regardless of their sexual orientation. A different research program indicates that men have lower second-to-fourth finger length ratios (2D:4D) than women, possibly because men are exposed to higher levels of androgens during prenatal development. We hypothesized that sex differences in sexual arousal patterns are influenced by prenatal androgen exposure and would thus be explained by sex differences in 2D:4D. We measured the sexual response patterns of 139 men and 179 women via genital arousal and pupil dilation to erotic videos, in addition to their 2D:4D. Compared to women, men showed stronger responses to one sex over the other, although this pattern was clearer in genital arousal than pupil dilation. Men also had lower 2D:4D than women. However, there was no evidence that sex differences in sexual arousal related to sex differences in 2D:4D. Thus, whichever factor explains sex differences in sexual arousal patterns may not be reflected in 2D:4D.
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Affiliation(s)
- Luke Holmes
- Department of Psychology, University of Essex
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13
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Knecht S, Nogueira L, Servant M, Santos F, Alunni V, Bernardi C, Quatrehomme G. Sex estimation from the greater sciatic notch: a comparison of classical statistical models and machine learning algorithms. Int J Legal Med 2021; 135:2603-2613. [PMID: 34554326 DOI: 10.1007/s00414-021-02700-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 09/09/2021] [Indexed: 11/28/2022]
Abstract
The greater sciatic notch (GSN) is a useful element for sex estimation because it is quite resistant to damage, and thus it can often be assessed even in poorly preserved skeletons. This study aimed to develop statistical models for sex estimation based on visual and metric analyses of the GSN, and additional variables linked to the GSN. A total of 60 left coxal bones (30 males and 30 females) were analysed. Fifteen variables were measured, and one was a morphologic variable. These 16 variables were used for the comparison of six statistical models: linear discriminant analysis (LDA), regularized discriminant analysis (RDA), penalized logistic regression (PLR) and flexible discriminant analysis (FDA), and two machine learning algorithms, support vector machine (SVM) and artificial neural network (ANN). The statistical models were built in two steps: firstly, only with the GSN variables (group 1), and secondly, with the whole variables (group 2), in order to see if the models including all the variables performed better. The overall accuracy of the models was very close, ranging from 0.92 to 0.97 using specific GSN variables. When additional variables starting from the deepest point of GSN are available, it is worth to use them, because the accuracy increases. PLR (after optimization of parameters) stands out from other statistical models. The position of the deepest point of GSN (Fig. 2) probably plays a crucial role for the sexual dimorphism, as stated by the good performance of the visual assessment of this point and the fact that the A2 angle (posterior angle with the deepest point of the GSN as the apex) is included in all models.
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Affiliation(s)
- Siam Knecht
- Faculté de Médecine, Université de Lorraine, 9 avenue de la Forêt de Haye, 54500, Vandœuvre-les-Nancy, France.
- Faculté de Médecine, Institut Universitaire d'Anthropologie Médico-Légale Université Côte d'Azur, 28 Avenue de Valombrose, 06107 cedex 2, Nice, France.
| | - Luísa Nogueira
- Faculté de Médecine, Institut Universitaire d'Anthropologie Médico-Légale Université Côte d'Azur, 28 Avenue de Valombrose, 06107 cedex 2, Nice, France
| | - Maël Servant
- Faculté de Médecine, Institut Universitaire d'Anthropologie Médico-Légale Université Côte d'Azur, 28 Avenue de Valombrose, 06107 cedex 2, Nice, France
| | - Frédéric Santos
- UMR 5199 PACEA, Université de Bordeaux, Allée Geoffroy Saint-Hilaire, Bâtiment B8, CS 50023, Cedex 33615, Pessac, France
| | - Véronique Alunni
- Faculté de Médecine, Institut Universitaire d'Anthropologie Médico-Légale Université Côte d'Azur, 28 Avenue de Valombrose, 06107 cedex 2, Nice, France
- CEPAM, UMR CNRS 7264, 24 avenue des Diables Bleus, 06300, Nice, France
| | - Caroline Bernardi
- Faculté de Médecine, Institut Universitaire d'Anthropologie Médico-Légale Université Côte d'Azur, 28 Avenue de Valombrose, 06107 cedex 2, Nice, France
- CEPAM, UMR CNRS 7264, 24 avenue des Diables Bleus, 06300, Nice, France
| | - Gérald Quatrehomme
- Faculté de Médecine, Institut Universitaire d'Anthropologie Médico-Légale Université Côte d'Azur, 28 Avenue de Valombrose, 06107 cedex 2, Nice, France
- CEPAM, UMR CNRS 7264, 24 avenue des Diables Bleus, 06300, Nice, France
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14
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Stansfield E, Fischer B, Grunstra NDS, Pouca MV, Mitteroecker P. The evolution of pelvic canal shape and rotational birth in humans. BMC Biol 2021; 19:224. [PMID: 34635119 PMCID: PMC8507337 DOI: 10.1186/s12915-021-01150-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 09/09/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND The human foetus typically needs to rotate when passing through the tight birth canal because of the complex shape of the pelvis. In most women, the upper part, or inlet, of the birth canal has a round or mediolaterally oval shape, which is considered ideal for parturition, but it is unknown why the lower part of the birth canal has a pronounced anteroposteriorly oval shape. RESULTS Here, we show that the shape of the lower birth canal affects the ability of the pelvic floor to resist the pressure exerted by the abdominal organs and the foetus. Based on a series of finite element analyses, we found that the highest deformation, stress, and strain occur in pelvic floors with a circular or mediolaterally oval shape, whereas an anteroposterior elongation increases pelvic floor stability. CONCLUSIONS This suggests that the anteroposterior oval outlet shape is an evolutionary adaptation for pelvic floor support. For the pelvic inlet, by contrast, it has long been assumed that the mediolateral dimension is constrained by the efficiency of upright locomotion. But we argue that the mediolateral elongation has evolved because of the limits on the anteroposterior diameter imposed by upright posture. We show that an anteroposteriorly deeper inlet would require greater pelvic tilt and lumbar lordosis, which compromises spine health and the stability of upright posture. These different requirements of the pelvic inlet and outlet likely have led to the complex shape of the pelvic canal and to the evolution of rotational birth characteristic of humans.
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Affiliation(s)
- Ekaterina Stansfield
- Department of Evolutionary Biology, Unit for Theoretical Biology, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria.
| | - Barbara Fischer
- Department of Evolutionary Biology, Unit for Theoretical Biology, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
| | - Nicole D S Grunstra
- Department of Evolutionary Biology, Unit for Theoretical Biology, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria
- Konrad Lorenz Institute for Evolution and Cognition Research, Martinstrasse 12, 3400, Klosterneuburg, Austria
- Mammal Collection, Natural History Museum Vienna, Burgring 7, 1010, Vienna, Austria
| | - Maria Villa Pouca
- Faculty of Engineering of University of Porto (FEUP), Rua Dr. Roberto Frias, s/n, 4200-465, Porto, Portugal
- Institute of Science and Innovation in Mechanical and Industrial Engineering (INEGI/LAETA), Rua Dr. Roberto Frias, 400, 4200-465, Porto, Portugal
| | - Philipp Mitteroecker
- Department of Evolutionary Biology, Unit for Theoretical Biology, University of Vienna, Djerassiplatz 1, 1030, Vienna, Austria.
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15
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Zorrilla-Revilla G, Rodríguez J, Mateos A. Gathering Is Not Only for Girls : No Influence of Energy Expenditure on the Onset of Sexual Division of Labor. HUMAN NATURE-AN INTERDISCIPLINARY BIOSOCIAL PERSPECTIVE 2021; 32:582-602. [PMID: 34570339 DOI: 10.1007/s12110-021-09411-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/23/2021] [Indexed: 11/24/2022]
Abstract
In some small-scale societies, a sexual division of labor is common. For subadult hunter-gatherers, the onset of this division dates to middle childhood and the start of puberty; however, there is apparently no physiological explanation for this timing. The present study uses an experimental approach to evaluate possible energetic differences by sex in gathering-related activities. The energetic cost of gathering-related activities was measured in a sample of 42 subjects of both sexes aged between 8 and 14 years. Body mass and other anthropometric variables were also recorded. Our results show that the energetic differences in the simulated gathering activities depend only on body mass. Both sexes expend a similar amount of energy during locomotion activities related to gathering. Discarding the energetic factor, the sexual division of tasks may be explained as an adaptation to acquire the skills needed to undertake the complex activities required during adulthood as early as possible. Carrying out gathering activities during childhood and adolescence could be favored by the growth and development cycles of Homo sapiens. Moreover, if most of the energetic costs of gathering activities depend on body mass, the delayed growth in humans relative to other primates allows subadults to practice these tasks for longer periods, and to become better at performing them. In fact, this strategy could enable them to acquire adults' complex skills at a low energetic cost that can be easily subsidized by other members of the group.
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Affiliation(s)
| | - Jesús Rodríguez
- National Research Center On Human Evolution (CENIEH), 09002, Burgos, Spain
| | - Ana Mateos
- National Research Center On Human Evolution (CENIEH), 09002, Burgos, Spain.
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16
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Audenaert EA, Duquesne K, De Roeck J, Mutsvangwa T, Borotikar B, Khanduja V, Claes P. Ischiofemoral impingement: the evolutionary cost of pelvic obstetric adaptation. J Hip Preserv Surg 2021; 7:677-687. [PMID: 34548927 PMCID: PMC8448428 DOI: 10.1093/jhps/hnab004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 01/06/2021] [Accepted: 01/13/2021] [Indexed: 12/29/2022] Open
Abstract
The risk for ischiofemoral impingement has been mainly related to a reduced ischiofemoral distance and morphological variance of the femur. From an evolutionary perspective, however, there are strong arguments that the condition may also be related to sexual dimorphism of the pelvis. We, therefore, investigated the impact of gender-specific differences in anatomy of the ischiofemoral space on the ischiofemoral clearance, during static and dynamic conditions. A random sampling Monte-Carlo experiment was performed to investigate ischiofemoral clearance during stance and gait in a large (n = 40 000) virtual study population, while using gender-specific kinematics. Subsequently, a validated gender-specific geometric morphometric analysis of the hip was performed and correlations between overall hip morphology (statistical shape analysis) and standard discrete measures (conventional metric approach) with the ischiofemoral distance were evaluated. The available ischiofemoral space is indeed highly sexually dimorphic and related primarily to differences in the pelvic anatomy. The mean ischiofemoral distance was 22.2 ± 4.3 mm in the females and 29.1 ± 4.1 mm in the males and this difference was statistically significant (P < 0.001). Additionally, the ischiofemoral distance was observed to be a dynamic measure, and smallest during femoral extension, and this in turn explains the clinical sign of pain in extension during long stride walking. In conclusion, the presence of a reduced ischiofemroal distance and related risk to develop a clinical syndrome of ischiofemoral impingement is strongly dominated by evolutionary effects in sexual dimorphism of the pelvis. This should be considered when female patients present with posterior thigh/buttock pain, particularly if worsened by extension. Controlled laboratory study.
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Affiliation(s)
- E A Audenaert
- Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Corneel Heymanslaan 10, Ghent 9000, Belgium.,Department of Trauma and Orthopedics, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge CB2 0QQ, UK.,Department of Electromechanics, Op3Mech Research Group, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium.,Department of Human Structure and Repair, Ghent University, Corneel Heymanslaan 10, Ghent 9000, Belgium
| | - K Duquesne
- Department of Human Structure and Repair, Ghent University, Corneel Heymanslaan 10, Ghent 9000, Belgium
| | - J De Roeck
- Department of Human Structure and Repair, Ghent University, Corneel Heymanslaan 10, Ghent 9000, Belgium
| | - T Mutsvangwa
- Division of Biomedical Engineering, University of Cape Town, Anzio Rd, Observatory, Cape Town 7925, South Africa
| | - B Borotikar
- Symbiosis Center for Medical Image Analysis, Symbiosis International University, Lavale, Mulshi District, Pune 412115, India.,Laboratory of Medical Information Processing (LaTIM), UMR 1101, INSERM, Avenue Foch 12, 29200 Brest, France
| | - V Khanduja
- Department of Trauma and Orthopedics, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge CB2 0QQ, UK
| | - P Claes
- Department of Human Genetics, KU Leuven, Herestraat 49, 3000 Leuven, Belgium.,Medical Imaging Research Center, University Hospitals Leuven, Herestraat 49, 3000 Leuven, Belgium.,Department of Electrical Engineering, ESAT/PSI, KU Leuven, Herestraat 49, 3000 Leuven, Belgium.,Murdoch Children's Research Institute, Melbourne, Flemington Road, Parkville Victoria 3052, Australia
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17
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Cox SL. A geometric morphometric assessment of shape variation in adult pelvic morphology. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021; 176:652-671. [PMID: 34528241 DOI: 10.1002/ajpa.24399] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 06/13/2021] [Accepted: 07/29/2021] [Indexed: 12/16/2022]
Abstract
OBJECTIVES In humans, the pelvis is the most sexually dimorphic skeletal element and is often utilized in aging and sexing remains. The pelvis has become greatly relied upon in anthropological research (e.g., forensics, demographics, obstetrics, evolutionary history); however, pelvis morphology is highly variable, and very little is known about the nature, sources, patterning, and interpretation of this variation. This study aims to quantify pelvis shape variation, document sexual shape variation, and estimate the plasticity of morphology. This will ultimately give greater ability to interpret modern, archaeological, and evolutionary patterns to gain deeper insight into processes which shape human anatomy. MATERIALS AND METHODS Using a sample of 129 Medieval Danish skeletons, shape variation is documented in the greater sciatic notch (GSN), iliac crest (IC), arcuate line (AL), and sub-pubic angle (SPA) using 3D geometric morphometrics. The landmarking method applied here has the advantage of being applicable to fragmentary remains, rather than requiring whole bones. This allows it to be easily applied to archaeological samples and for the interpretation of separate bone features. Differences in shape were statistically analyzed by principle component analysis, linear discriminate analysis, and morphological disparity. Relationships between maximum femur length, body mass, and shape centroid size were also test by allometric regression. RESULTS Results quantify the sexual dimorphism and shape variation present in these features. The GSN shape is the most variable, while the AL is the least. Similarly, the IC is the only feature which shows almost no dimorphism in shape, and instead best reflects lifestyle/activity patterns. Evidence of dimorphism in the IC is likely a result of cultural labor patterns rather than genetic and hormonal influence. Finally, the shapes of the GSN, AL, and SPA are more related to body mass than to femur length, such that individuals with increased mass exhibit more classically "male" shapes and those with less mass have more "female" shapes. DISCUSSION The results have important implications for the evolution of pelvic anatomy, and sexual dimorphism, but also highlight the plasticity inherent in pelvic morphology. Analyzing pelvis features separately in a clearly defined, relatively genetically homogenous population gives insight into the determinants of bone morphology, which are not readily observable by other means. The relationship between body mass and shape suggests dimorphism in body size and composition may affect bone shape.
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Affiliation(s)
- Samantha L Cox
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Physical Anthropology, Penn Museum, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,University of Cambridge, Department of Archaeology, Cambridge, UK
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18
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Liu J, Salem GJ, Powers CM. Sex Difference in Hip Adduction during the Stance Phase of Running: A Swing Phase Problem? Med Sci Sports Exerc 2021; 53:1412-1416. [PMID: 34127634 DOI: 10.1249/mss.0000000000002610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE The purpose of the current study was 1) to evaluate sex differences in peak hip adduction during the late swing and stance phases of running and 2) to determine whether peak hip adduction during late swing is predictive of peak hip adduction during stance. METHODS A total of 15 female and 16 male heel strike runners ran over ground at a speed of 4 m·s-1. Hip joint kinematics during running were quantified using a 3D motion capture system. Sex differences in peak hip adduction during the late swing and stance phases were compared using independent-samples t-tests. Linear regression analysis was used to determine the relationship between late swing and stance phase hip adduction. RESULTS Compared with males, females exhibited significantly greater peak hip adduction during both the late swing (8.5° ± 2.6° vs 6.1° ± 2.8°, P = 0.019) and the stance phases of running (13.3° ± 4.2° vs 9.6° ± 3.4°, P = 0.011). Furthermore, late swing peak hip adduction was predictive of subsequent stance phase peak hip adduction (r = 0.63, P < 0.001). CONCLUSION Sex differences in hip adduction during stance are influenced in part by late swing phase hip adduction. Further studies are needed to identify potential causes of excessive hip adduction during the late swing phase of running.
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Affiliation(s)
- Jia Liu
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA
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19
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Moffett EA. Sexual dimorphism in the size and shape of the non-obstetric pelvis across anthropoids. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021; 176:402-421. [PMID: 34453450 DOI: 10.1002/ajpa.24398] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 04/26/2021] [Accepted: 07/20/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVES The presence of sexual dimorphism in the birth canals of anthropoid primates is well documented, and birth canal dimorphism tends to be especially robust among species that give birth to relatively large neonates. However, it is less clear whether birth canal dimorphism is accompanied by dimorphism in parts of the pelvis not directly under selection for birth, particularly including bi-iliac breadth, biactetabular breadth, lengths of the ischium and ilium, and 3D shape. This study investigates the patterns of dimorphism among anthropoid primates in those parts of the pelvis which do not directly contribute to the bony birth canal, here termed the non-obstetric pelvis. METHODS 3D landmark data were collected on the bony pelves of 899 anthropoid primates. Specifically, landmark data were collected on parts of the pelvis not thought to be directly involved in selection for parturition, including portions of the posterior and superior ilium, acetabulum, and lateral ischium. Principal components analysis and Euclidean distance matrix analysis were used to ascertain sexual dimorphism in pelvic sizes and shapes within each species. RESULTS Results show that dimorphism in non-obstetric pelvic size and shape exists across anthropoids, just as is seen in the birth canal. However, the magnitude of dimorphism in non-obstetric pelvic shape tends to be greater among anthropoid species that give birth to relatively large neonates compared with those birthing smaller neonates relative to maternal pelvic size. CONCLUSIONS Though all anthropoids included in the study show some degree of sexual dimorphism in non-obstetric pelvic size and/or shape, species which give birth to large neonates relative to maternal pelvic size have the highest levels of dimorphism in pelvic shape. Moreover, the magnitude of dimorphism in certain parts of the non-obstetric pelvis mirrors patterns seen in the birth canal. The results of this study are promising for ascertaining pelvic dimorphism and relative neonate size in fossil primates, particularly in fragmentary remains which do not preserve a complete bony birth canal.
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Affiliation(s)
- Elizabeth A Moffett
- Department of Clinical Anatomy and Osteopathic Principles, Rocky Vista University, Parker, Colorado, USA
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20
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Fox MC, Konigsberg LW, Hsiao-Wecksler ET, Whitcome KK, Polk JD. Scaling of linear anthropometric dimensions in living humans. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021; 176:134-143. [PMID: 33782957 DOI: 10.1002/ajpa.24275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/18/2021] [Accepted: 03/07/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVES Some previous studies suggest that humans do not conform to geometric similarity (isometry) in anthropometric dimensions of the upper and lower limbs. Researchers often rely on a single statistical approach to the study of scaling patterns, and it is unclear whether these methods produce similar results and are equally robust. This study used one bivariate and one multivariate method to examine how linear anthropometric dimensions scale in a sample of adult humans. MATERIALS AND METHODS Motion capture marker data from 104 adults of varying height and mass were used to calculate anthropometric dimensions. We analyzed scaling patterns in pooled and separate sexes with two methods: (1) bivariate log-log regression and (2) multivariate principal component analysis (PCA). We calculated 95% highest density/confidence intervals for each method and defined positive/negative allometry as estimates lying outside those intervals. RESULTS Results identified isometric scaling of the upper arm, thigh, and shoulder, positive allometry of the forearm and shank, and negative allometry of the pelvis in the pooled sample using both statistical methods. Patterns of allometry in the pooled sample were similar between methods but differed in magnitude. Sex-specific results differed in both pattern and magnitude between log-log regression and PCA. Only one measurement (shoulder width) departed from isometry in the sex-specific log-log regressions. DISCUSSION Our findings suggest that especially in sex-specific analyses, the pattern and magnitude of allometry are sensitive to statistical methodology. When body mass was selected as the size variable, most human linear anthropometric dimensions in this sample scaled isometrically and were therefore geometrically similar within sexes.
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Affiliation(s)
- Maria C Fox
- Anthropology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Lyle W Konigsberg
- Anthropology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Elizabeth T Hsiao-Wecksler
- Mechanical Science & Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Biomedical & Translational Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | | | - John D Polk
- Anthropology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.,Biomedical & Translational Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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21
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Waltenberger L, Pany‐Kucera D, Rebay‐Salisbury K, Mitteroecker P. The association of parturition scars and pelvic shape: A geometric morphometric study. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021; 174:519-531. [PMID: 33295660 PMCID: PMC7898533 DOI: 10.1002/ajpa.24196] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 11/09/2020] [Accepted: 11/19/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Pelvic features, mostly known as parturition scars, have been extensively studied in the last decades and are frequently investigated in archaeological and forensic contexts. It is still unclear, however, whether they really relate to pregnancy and birth, or whether these features are caused by other biomechanical factors. Because the length and difficulty of labor correlates with the form of the birth canal, we studied the association between the expression of pelvic features and pelvic shape using geometric morphometrics. MATERIALS AND METHODS We scored the expression of the preauricular sulcus, margo auricularis groove, sacral preauricular extension, dorsal and ventral pubic pitting for 54 individuals from a 19th century collection and 19 individuals from the Bronze Age cemetery of Hainburg-Teichtal, Austria. Based on photogrammetric surface models, pelvic shape was captured by 331 landmarks and semilandmarks. The multivariate association between pelvic features and pelvic shape was explored by partial least squares analysis. RESULTS Within the female subsample, we detected a significant association of a constrained birth canal with a strong expression of the preauricular sulcus, the margo auricularis groove, and a retroverted position of the acetabulum. No significant association was found among males. DISCUSSION This suggests that difficult or prolonged labor may indeed cause more strongly expressed pelvic features, presumably because of increased strain of the pelvic ligaments during birth. Furthermore, the retroversion of the acetabulum, which is known to cause sacroiliac joint dysfunction, changes the strain on pelvic ligaments and can thus also result in the development of pronounced pelvic features.
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Affiliation(s)
- Lukas Waltenberger
- OREA ‐ Institute for Oriental and European Archaeology, Austrian Academy of SciencesViennaAustria
- Department of Evolutionary BiologyUniversity of ViennaViennaAustria
| | - Doris Pany‐Kucera
- OREA ‐ Institute for Oriental and European Archaeology, Austrian Academy of SciencesViennaAustria
- Department of AnthropologyNatural History MuseumViennaAustria
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22
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Waxenbaum EB, Feiler ME. Influence of climatic stress on nonmetric sexually dimorphic features of the skull and pelvis. Am J Hum Biol 2020; 33:e23559. [PMID: 33377211 DOI: 10.1002/ajhb.23559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 11/05/2020] [Accepted: 12/11/2020] [Indexed: 11/09/2022] Open
Abstract
OBJECTIVES Human sexual dimorphism is frequently assessed through skull and pelvic size and shape. Researchers suggest that climatic variation and the associated stress may be significant factors in sexual dimorphism's etiology. However, little research has specifically investigated climatic effects on nonmetric skeletal indicators of sex. To further appreciate the plasticity of human biology, a comparative study of standard skull and pelvic nonmetric sex indicators is presented. METHODS A Native Alaskan archeological sample (n = 104) and a component of the Terry collection (n = 99) represent populations originating from different climatic environments in recent history. These sex-balanced groups are compared through Tukey-Kramer's method and Greene's t-test to determine any variation in degree of sexual dimorphism within and between samples. RESULTS The results reinforce the complex and multifaceted relationship between climate and sexual dimorphism. The Terry sample demonstrated a greater degree of sexual dimorphism with statistically significant differences in robusticity of the mastoid process and nuchal crest compared with the Native Alaskans. A more "male" morphotype and reduced dimorphism are appreciated in the pelves of Native Alaskans than the Terry sample. CONCLUSIONS This research highlights a reduction in sexual dimorphism in populations under greater climatic stress and contributes to the production of more accurate skeletal assessments in future investigations. Discussion of confounding factors suggest more research is necessary to untangle climate and human morphology's complex relationship. This study contributes to a greater appreciation of human biological plasticity, ecogeographic variation, and the evolution of modern human diversity.
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Affiliation(s)
- Erin B Waxenbaum
- Department of Anthropology, Northwestern University, Evanston, Illinois, USA
| | - Maria E Feiler
- Department of Anthropology, Northwestern University, Evanston, Illinois, USA
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23
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Torres-Tamayo N, Martelli S, Schlager S, García-Martínez D, Sanchis-Gimeno JA, Mata-Escolano F, Nalla S, Ogihara N, Oishi M, Bastir M. Assessing thoraco-pelvic covariation in Homo sapiens and Pan troglodytes: A 3D geometric morphometric approach. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2020; 173:514-534. [PMID: 32864759 DOI: 10.1002/ajpa.24103] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 05/31/2020] [Accepted: 06/11/2020] [Indexed: 12/18/2022]
Abstract
OBJECTIVES Understanding thoraco-pelvic integration in Homo sapiens and their closest living relatives (genus Pan) is of great importance within the context of human body shape evolution. However, studies assessing thoraco-pelvic covariation across Hominoidea species are scarce, although recent research would suggest shared covariation patterns in humans and chimpanzees but also species-specific features, with sexual dimorphism and allometry influencing thoraco-pelvic covariation in these taxa differently. MATERIAL AND METHODS N = 30 adult H. sapiens and N = 10 adult Pan troglodytes torso 3D models were analyzed using 3D geometric morphometrics and linear measurements. Effects of sexual dimorphism and allometry on thoraco-pelvic covariation were assessed via regression analyses, and patterns of thoraco-pelvic covariation in humans and chimpanzees were computed via Two-Block Partial Least Squares analyses. RESULTS Results confirm the existence of common aspects of thoraco-pelvic covariation in humans and chimpanzees, and also species-specific covariation in H. sapiens that is strongly influenced by sexual dimorphism and allometry. Species-specific covariation patterns in chimpanzees could not be confirmed because of the small sample size, but metrics point to a correspondence between the most caudal ribs and iliac crest morphology that would be irrespective of sex. CONCLUSIONS This study suggests that humans and chimpanzees share common aspects of thoraco-pelvic covariation but might differ in others. In humans, torso integration is strongly influenced by sexual dimorphism and allometry, whilst in chimpanzees it may not be. This study also highlights the importance not only of torso widths but also of torso depths when describing patterns of thoraco-pelvic covariation in primates. Larger samples are necessary to support these interpretations.
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Affiliation(s)
- Nicole Torres-Tamayo
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain.,GIAVAL Research Group, Department of Anatomy and Human Embryology, University of Valencia, Valencia, Spain
| | - Sandra Martelli
- UCL Centre for Integrative Anatomy (CIA), Department of Cell and Developmental Biology, Faculty of Life Sciences, London, UK
| | - Stefan Schlager
- Biological Anthropology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Daniel García-Martínez
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain.,Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Burgos, Spain
| | | | | | - Shahed Nalla
- GIAVAL Research Group, Department of Anatomy and Human Embryology, University of Valencia, Valencia, Spain.,Department of Human Anatomy and Physiology, Faculty of Health Sciences, University of Johannesburg, Johannesburg, South Africa
| | - Naomichi Ogihara
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Motoharu Oishi
- Laboratory of Anatomy 1, School of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Markus Bastir
- Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain
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Kenyon-Flatt B, Conaway MA, Lycett SJ, von Cramon-Taubadel N. The relative efficacy of the cranium and os coxa for taxonomic assessment in macaques. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2020; 173:350-367. [PMID: 32594518 DOI: 10.1002/ajpa.24100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/07/2020] [Accepted: 05/20/2020] [Indexed: 11/08/2022]
Abstract
OBJECTIVES The cranium is generally considered more reliable than the postcranium for assessing primate taxonomy, although recent research suggests that pelvic shape may be equally reliable. However, little research has focused on intrageneric taxonomic discrimination. Here, we test the relative taxonomic efficacy of the cranium and os coxa for differentiating two macaque species, with and without considering sexual dimorphism. MATERIALS AND METHODS Geometric morphometric analyses were performed on cranial and os coxa landmarks for 119 adult Macaca fascicularis, M. mulatta, and Chlorocebus pygerythrus. Among-group shape variation was examined using canonical variates analyses. Cross-validated discriminant function analysis provided rates of correct group classification. Additionally, average morphological distances were compared with neutral genetic distances. RESULTS Macaque species were clearly differentiated, both cranially and pelvically, when sex was not considered. Males were more often correctly classified based on the os coxa, while female classification rates were high for both morphologies. Female crania and male os coxa were differentiated approximately the same as genetic distance, while male crania were more similar (convergent), and female os coxa were more divergent than expected based on genetic distance. DISCUSSION The hypothesis that cranial and os coxal shape can be used to discriminate among macaque species was supported. The cranium was better at differentiating females, while the os coxa was better at differentiating male macaques. Hence, there is no a priori reason for preferring the cranium when assessing intragenetic taxonomic relationships, but the effects of high levels of sexual dimorphism must be corrected for to accurately assess taxonomic signatures.
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Affiliation(s)
- Brittany Kenyon-Flatt
- Buffalo Human Evolutionary Morphology Lab, Department of Anthropology, University at Buffalo, Buffalo, New York, USA
| | - Mark A Conaway
- Buffalo Human Evolutionary Morphology Lab, Department of Anthropology, University at Buffalo, Buffalo, New York, USA
| | - Stephen J Lycett
- Department of Anthropology, University at Buffalo, Buffalo, New York, USA
| | - Noreen von Cramon-Taubadel
- Buffalo Human Evolutionary Morphology Lab, Department of Anthropology, University at Buffalo, Buffalo, New York, USA
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25
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Ricklan SJ, Decrausaz SL, Wells JCK, Stock JT. Obstetric dimensions of the female pelvis are less integrated than locomotor dimensions and show protective scaling patterns: Implications for the obstetrical dilemma. Am J Hum Biol 2020; 33:e23451. [PMID: 32567787 DOI: 10.1002/ajhb.23451] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 05/14/2020] [Accepted: 05/15/2020] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES The "obstetrical dilemma" hypothesis assumes that the modern human female pelvis serves two discrete functions: obstetrics and locomotion. We investigate whether these differing functions create observable patterns of morphological covariation and whether those patterns differ by height, weight, and age. This allows evaluation of evidence for canalization and phenotypic plasticity relevant to obstetric and locomotor function among a living female population. METHODS Landmarks (N = 86) were collected and inter-landmark distances were calculated (N = 36) on the pelvis and proximal femur of CT scans of living women aged 20 to 90 years (M = 93) receiving a routine CT scan. Partial least squares and relative SD of eigenvalues analyses were used to evaluate integration overall and within locomotor and obstetric modules, respectively. Ordinary Least Squared regression was used to evaluate scaling relationships between inter-landmark distances and height, weight, and age. RESULTS The obstetric pelvis was significantly less internally integrated than the locomotor pelvis. Many obstetric measurements were constrained in absolute terms relative to height; shorter women had relatively larger birth canal dimensions, and several key obstetric dimensions showed relative freedom from height. Lower weight women had some relatively larger obstetric and locomotor dimensions. Regarding age, younger women showed a few relatively larger outlet dimensions. CONCLUSIONS This study suggests that the obstetric pelvis and the locomotor pelvis function are morphologically distinct, with the obstetric pelvis showing relatively greater flexibility. These relationships between relative constraints support the hypothesis that the modern female pelvis shows evidence of both canalization and phenotypic plasticity in obstetric and locomotor structures.
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Affiliation(s)
- Sarah J Ricklan
- Department of Archaeology, University of Cambridge, Cambridge, UK.,New York University Grossman School of Medicine, New York, New York, USA
| | - Sarah-Louise Decrausaz
- Department of Archaeology, University of Cambridge, Cambridge, UK.,Department of Anthropology, University of Victoria, Victoria, British Columbia, Canada
| | - Jonathan C K Wells
- Childhood Nutrition Research Centre, Population, Policy, and Practice Research and Teaching Department, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Jay T Stock
- Department of Archaeology, University of Cambridge, Cambridge, UK.,Department of Anthropology, Western University, London, Ontario, Canada.,Department of Archaeology, Max Planck Centre for the Science of Human History, Jena, Germany
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26
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Uy J, Hawks J, VanSickle C. Sexual dimorphism of the relationship between the gut and pelvis in humans. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2020; 173:130-140. [PMID: 32519366 DOI: 10.1002/ajpa.24084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 02/04/2020] [Accepted: 05/06/2020] [Indexed: 01/12/2023]
Abstract
OBJECTIVES Obstetric demands have long been considered in the evolution of the pelvis, yet consideration of the interaction of pregnancy, the pelvis, and the gastrointestinal tract (gut) is lacking. Here, we explore sex differences in the relationship of gut volume with body size and pelvic dimensions. MATERIALS AND METHODS Computed tomography (CT) scans of living adult Homo sapiens (46 females and 42 males) were obtained to measure in vivo gut volume (GV) and to extract 3D models of the pelvis. We collected 19 3D landmarks from each pelvis model to acquire pelvic measurements. We used ordinary least squares regression to explore relationships between GV and body weight, stature, and linear pelvic dimensions. RESULTS The gut-pelvis relationship differs between males and females. Females do not exhibit significant statistical correlations between GV and any variable tested. GV correlates with body size and pelvic outlet size in males. GV scales with negative allometry relative to body weight, stature, maximum bi-iliac breadth, inferior transverse outlet breadth, and bispinous distance in males. DISCUSSION The lack of association between GV and body size in females may be due to limits imposed by the anticipation of accommodating a gravid uterus and/or the increased plasticity of the pelvis. The pattern of relationship between GV and the pelvic outlet suggests the role of the bony pelvis in supporting the adominal viscera in females may be small relative to its role in childbirth. We conclude that gut size inference in fossil hominins from skeletal proxies is limited and confounded by sexual dimorphism.
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Affiliation(s)
- Jeanelle Uy
- Department of Anthropology, California State University, Long Beach, California, USA
| | - John Hawks
- Department of Anthropology, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Johannesburg, South Africa
| | - Caroline VanSickle
- Department of Anatomy, A.T. Still University Kirksville College of Osteopathic Medicine, 800 W. Jefferson St., Kirksville, Missouri, USA
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27
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Audenaert E, Van den Eynde J, de Almeida D, Steenackers G, Vandermeulen D, Claes P. Separating positional noise from neutral alignment in multicomponent statistical shape models. Bone Rep 2020; 12:100243. [PMID: 32181268 PMCID: PMC7063239 DOI: 10.1016/j.bonr.2020.100243] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/26/2019] [Accepted: 01/06/2020] [Indexed: 12/13/2022] Open
Abstract
Given sufficient training samples, statistical shape models can provide detailed population representations for use in anthropological and computational genetic studies, injury biomechanics, musculoskeletal disease models or implant design optimization. While the technique has become extremely popular for the description of isolated anatomical structures, it suffers from positional interference when applied to coupled or articulated input data. In the present manuscript we describe and validate a novel approach to extract positional noise from such coupled data. The technique was first validated and then implemented in a multicomponent model of the lower limb. The impact of noise on the model itself as well as on the description of sexual dimorphism was evaluated. The novelty of our methodology lies in the fact that no rigid transformations are calculated or imposed on the data by means of idealized joint definitions and by extension the models obtained from them.
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Affiliation(s)
- E.A. Audenaert
- Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Corneel Heymanslaan 10, 9000 Ghent, Belgium
- Department of Human Structure and Repair, Ghent University, Corneel Heymanslaan 10, 9000 Ghent, Belgium
- Department of Trauma and Orthopedics, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge CB2 0QQ, UK
- Department of Electromechanics, Op3Mech research group, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - J. Van den Eynde
- Department of Human Structure and Repair, Ghent University, Corneel Heymanslaan 10, 9000 Ghent, Belgium
| | - D.F. de Almeida
- Centre for Rapid and Sustainable Product Development, Polytechnic Institute of Leiria, Portugal
| | - G. Steenackers
- Department of Electromechanics, Op3Mech research group, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - D. Vandermeulen
- Department of Electrical Engineering, ESAT/PSI, KU Leuven, Kasteelpark Arenberg 10, box 2441, 3001 Leuven, Belgium
- Department of Human Genetics, KU Leuven, Herestraat 49, box 602, 3000 Leuven, Belgium
| | - P. Claes
- Department of Electrical Engineering, ESAT/PSI, KU Leuven, Kasteelpark Arenberg 10, box 2441, 3001 Leuven, Belgium
- Department of Human Genetics, KU Leuven, Herestraat 49, box 602, 3000 Leuven, Belgium
- Murdoch Children's Research Institute, Royal Children's Hospital, Flemington Rd, Parkville 3052, Melbourne, Victoria, Australia
- Department of Biomedical Engineering, University of Oxford, Old Road Campus Research Building, Headington, Oxford OX3 7DQ, United Kingdom
- Medical Imaging Research Center, MIRC, University Hospitals Leuven, Herestraat 49 - 7003, 3000 Leuven, Belgium
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Jerković I, Bašić Ž, Anđelinović Š, Kružić I. Adjusting posterior probabilities to meet predefined accuracy criteria: A proposal for a novel approach to osteometric sex estimation. Forensic Sci Int 2020; 311:110273. [PMID: 32272305 DOI: 10.1016/j.forsciint.2020.110273] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 03/19/2020] [Accepted: 03/25/2020] [Indexed: 11/29/2022]
Abstract
The osteometric methods are the most reliable way to estimate the sex of skeletons when DNA analysis is not used. However, as osteometric studies usually ignore the overlap in male and female skeletal dimensions, they rarely achieve accuracy sufficient for forensic application. To resolve this issue, recent studies suggest sex estimation only when posterior probability (pp) is greater than 0.95, but that approach does not always provide sufficient accuracy and creates a large proportion of unsexed skeleton. Thus, our study aimed to explore whether it is possible to adjust pp on skeletal measurements with pronounced sexual dimorphism to meet 95% accuracy and to enable sex estimation on a reasonable proportion of individuals. From 207 skeletons, we included 65 postcranial measurements and selected 10% of variables with the highest sexual dimorphism. We computed univariate and bivariate discriminant functions using pp threshold of 0.5, 0.95, and the threshold required to achieve accuracy of ≥ 95%. Discriminant functions with pp=0.5 obtained accuracy of 85%-93%, while those with pp≥0.95 and adjusted posterior probabilities obtained 94%-99%. However, we showed that by selecting a particular threshold, sex could be estimated on a greater proportion of individuals than for pp≥0.95: 42%-86% vs. 24%-62% for univariate and 69%-95% vs. 49%-78% for bivariate functions. Therefore, when developing sex estimation models, we suggest not to use fixed pp level, but to adjust pp to achieve 95% accuracy and to minimize the percentage of unsexed skeletons.
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Affiliation(s)
- Ivan Jerković
- University Department of Forensic Sciences, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia
| | - Željana Bašić
- University Department of Forensic Sciences, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia.
| | - Šimun Anđelinović
- University of Split, School of Medicine, Šoltanska 2, 21000 Split, Croatia; Clinical Department for Pathology, Legal Medicine and Cytology, University Hospital Center Split, Spinčićeva 1, 21000 Split, Croatia
| | - Ivana Kružić
- University Department of Forensic Sciences, University of Split, Ruđera Boškovića 33, 21000 Split, Croatia
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29
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Nishi K, Saiki K, Oyamada J, Okamoto K, Ogami-Takamura K, Hasegawa T, Moriuchi T, Sakamoto J, Higashi T, Tsurumoto T, Manabe Y. Sex-based differences in human sacroiliac joint shape: a three-dimensional morphological analysis of the iliac auricular surface of modern Japanese macerated bones. Anat Sci Int 2019; 95:219-229. [PMID: 31792910 DOI: 10.1007/s12565-019-00513-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 11/25/2019] [Indexed: 11/30/2022]
Abstract
The human pelvis is one of the skeletons where sex differences are expressed, but few detailed studies have been conducted on sex-related differences in the sacroiliac joint morphology. Therefore, we conducted a three-dimensional morphological analysis evaluation of the sacroiliac joints to clarify the sex-related difference of the joint's morphology. Right-side macerated innominate bones of Japanese males (n = 100) and females (n = 70) whose ages at death were recorded were included in the study. Three-dimensional images were created from the subjects' iliac auricular surface images, and 16 measurement parameters were acquired on the basis of 11 defined measurement points. All measurement parameters were compared between the male and female groups. The values of the measurement parameters indicating the size of the iliac auricular surface were significantly larger in the male group than in the female group. In addition, the angle between the short and long arms of the auricular surface was larger in the male group. Furthermore, on the basis of the corrected values of the physical disparity, the long arm dimension of the iliac auricular surface was larger in the male group, while the short arm dimension was larger in the female group. The sex-based differences in the iliac auricular surface morphology that were confirmed in this study may reflect the sex-based differences in the sacroiliac joint function. The findings of this study may contribute to the elucidation of the pathophysiology of the sacroiliac joint dysfunction that frequently occurs in women.
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Affiliation(s)
- Keita Nishi
- Department of Oral Anatomy and Dental Anthropology, Graduate School of Biomedical Sciences, Nagasaki University, Sakamoto 1-7-1, Nagasaki, 852-8588, Japan.
| | - Kazunobu Saiki
- Department of Macroscopic Anatomy, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Joichi Oyamada
- Department of Oral Anatomy and Dental Anthropology, Graduate School of Biomedical Sciences, Nagasaki University, Sakamoto 1-7-1, Nagasaki, 852-8588, Japan
| | - Keishi Okamoto
- Department of Macroscopic Anatomy, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Keiko Ogami-Takamura
- Department of Macroscopic Anatomy, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Takashi Hasegawa
- Department of Community-Based Rehabilitation Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Takefumi Moriuchi
- Department of Occupational Therapy Science, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Junya Sakamoto
- Department of Physical Therapy Science, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Toshio Higashi
- Department of Community-Based Rehabilitation Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Toshiyuki Tsurumoto
- Department of Macroscopic Anatomy, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yoshitaka Manabe
- Department of Oral Anatomy and Dental Anthropology, Graduate School of Biomedical Sciences, Nagasaki University, Sakamoto 1-7-1, Nagasaki, 852-8588, Japan
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30
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Audenaert EA, Pattyn C, Steenackers G, De Roeck J, Vandermeulen D, Claes P. Statistical Shape Modeling of Skeletal Anatomy for Sex Discrimination: Their Training Size, Sexual Dimorphism, and Asymmetry. Front Bioeng Biotechnol 2019; 7:302. [PMID: 31737620 PMCID: PMC6837998 DOI: 10.3389/fbioe.2019.00302] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 10/16/2019] [Indexed: 12/02/2022] Open
Abstract
Purpose: Statistical shape modeling provides a powerful tool for describing and analyzing human anatomy. By linearly combining the variance of the shape of a population of a given anatomical entity, statistical shape models (SSMs) identify its main modes of variation and may approximate the total variance of that population to a selected threshold, while reducing its dimensionality. Even though SSMs have been used for over two decades, they lack in characterization of their goodness of prediction, in particular when defining whether these models are actually representative for a given population. Methods: The current paper presents, to the authors' knowledge, the most extent lower limb anatomy shape model considering the pelvis, femur, patella, tibia, fibula, talus, and calcaneum to date. The present study includes the segmented training shapes (n = 542) obtained from 271 lower limb CT scans. The different models were evaluated in terms of accuracy, compactness, generalizability as well as specificity. Results: The size of training samples needed in each model so that it can be considered population covering was estimated to approximate around 200 samples, based on the generalizability properties of the different models. Simultaneously differences in gender and patterns in left-right asymmetry were identified and characterized. Size was found to be the most pronounced sexual discriminator whereas intra-individual variations in asymmetry were most pronounced at the insertion site of muscles. Conclusion: For models aimed at population covering descriptive studies, the number of training samples required should amount a sizeable 200 samples. The geometric morphometric method for sex discrimination scored excellent, however, it did not largely outperformed traditional methods based on discrete measures.
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Affiliation(s)
- E A Audenaert
- Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Ghent, Belgium.,Department of Trauma and Orthopedics, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom.,Op3Mech Research Group, Department of Electromechanics, University of Antwerp, Antwerp, Belgium
| | - C Pattyn
- Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Ghent, Belgium
| | - G Steenackers
- Op3Mech Research Group, Department of Electromechanics, University of Antwerp, Antwerp, Belgium
| | - J De Roeck
- Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Ghent, Belgium
| | - D Vandermeulen
- Medical Imaging Research Center, University Hospitals Leuven, Leuven, Belgium.,Department of Electrical Engineering, ESAT/PSI, KU Leuven, Leuven, Belgium
| | - P Claes
- Medical Imaging Research Center, University Hospitals Leuven, Leuven, Belgium.,Department of Electrical Engineering, ESAT/PSI, KU Leuven, Leuven, Belgium.,Department of Human Genetics, KU Leuven, Leuven, Belgium.,Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, Australia.,Department of Biomedical Engineering, University of Oxford, Oxford, United Kingdom
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31
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d'Oliveira Coelho J, Curate F. CADOES: An interactive machine-learning approach for sex estimation with the pelvis. Forensic Sci Int 2019; 302:109873. [PMID: 31382223 DOI: 10.1016/j.forsciint.2019.109873] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 11/29/2022]
Abstract
The pelvis is consistently regarded as the most sexually dimorphic region of the human skeleton, and methods for sex estimation with the pelvic bones are usually very accurate. In this investigation, population-specific osteometric models for the assessment of sex with the pelvis were designed using a dataset provided by J.A. Serra (1938) that included 256 individuals (131 females and 125 males) from the Coimbra Identified Skeletal Collection and 38 metric variables. The models for sex estimation were operationalized through an online application and decision support system, CADOES. Different classification algorithms generated high accuracy models, ranging from 85% to 92%, with only three variables; and from 85.33% to 97.33%, with all 38 variables. CADOES conveys a probabilistic prediction of skeletal sex, as well as a suite of attributes with educational applicability in the fields of human skeletal anatomy and statistics. This study upholds the value of the pelvis for the estimation of skeletal sex and provides models for that can be applied with high accuracy and low bias.
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Affiliation(s)
- João d'Oliveira Coelho
- Institute of Cognitive and Evolutionary Anthropology, University of Oxford, Oxford, United Kingdom; Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.
| | - Francisco Curate
- Laboratory of Forensic Anthropology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Research Centre for Anthropology and Health, Department of Life Sciences, University of Coimbra, Portugal
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32
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DelPrete H. Similarities in pelvic dimorphisms across populations. Am J Hum Biol 2019; 31:e23282. [DOI: 10.1002/ajhb.23282] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 04/04/2019] [Accepted: 05/29/2019] [Indexed: 12/31/2022] Open
Affiliation(s)
- Hillary DelPrete
- Department of History and AnthropologyMonmouth University Long Branch New Jersey
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33
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Robertson HI, Pokotylo DL, Weston DA. Testing landmark redundancy for sex-based shape analysis of the adult human os coxa. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:689-703. [PMID: 31155703 DOI: 10.1002/ajpa.23860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 04/13/2019] [Accepted: 05/13/2019] [Indexed: 12/27/2022]
Abstract
OBJECTIVES To test the individual effectiveness of common landmarks used in sex estimation of whole adult coxal bones in sex-based shape analysis and propose a method to determine how many principal components of sex-based shape to include for discriminant function analysis. METHODS Three-dimensional models (NextEngine desktop laser scanner) of left and right os coxae from 396 individuals (William Bass Skeletal Collection, Forensic Anthropology Centre, University of Tennessee, Knoxville, TN) were subjected to shape analysis using 32 landmarks (Landmark 3.6, Institute for Data Analysis and Visualization). Each landmark was individually removed and subjected to a new principal component analysis to identify the effect omitting a landmark has on PC1/PC2 ordination. Landmarks that poorly discriminated sex-based shape were considered redundant for analysis on sex estimation. RESULTS This study identified 17 landmarks that represent sex-based shape of right and left coxal bones most effectively, these are: the anterior superior iliac spine; posterior superior iliac spine; posterior inferior iliac spine; iliac crest; apex of the auricular surface; greater sciatic notch; ischial spine; superior, inferior and distal points on ischial tuberosity; superior, inferior and midpoint on the symphyseal face; arcuate eminence; ischiopubic ramus; posterosuperior and anterosuperior points on the acetabular rim. The first and second PCs of the 17-landmark configuration correctly predicted sex in 98.5% of cases; better than a 32-landmark configuration (96%) and better than previous landmark studies on whole coxal bone sex-based shape. CONCLUSIONS These 17 landmarks represent more meaningful data for sex-based shape analysis in PC1 and 2 and concentrate meaningful sex-based shape data to the first five PCs that make up over 50% of the total shape variance.
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Affiliation(s)
- Heather I Robertson
- Department of Anthropology, University of British Columbia, Vancouver, British Columbia, Canada
| | - David L Pokotylo
- Department of Anthropology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Darlene A Weston
- Department of Anthropology, University of British Columbia, Vancouver, British Columbia, Canada
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Takamuku H. Does obstetric protection apply to small-bodied females?: A comparison between small-bodied Jomon foragers and large-bodied Yayoi agriculturalists in the prehistoric Japanese archipelago. Am J Hum Biol 2019; 31:e23236. [PMID: 30968505 DOI: 10.1002/ajhb.23236] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 01/07/2019] [Accepted: 02/24/2019] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVES This study examined the relationship between maternal pelvic and body size in the transition from the Middle-Final Jomon period (c. 5000-3000 BC) to the Middle Yayoi period (c. 400~200 BC to around AD 1) in Japan. METHODS Eight measurements, including the left hip bone, articulated pelvis, and femur, were taken from Jomon (females: 37, males: 26) and Yayoi skeletal remains (females: 32, males: 29). RESULTS A statistically significant decrease in the anterior diameter of the true pelvic inlet was demonstrated in females from the Jomon to the Yayoi period, but not in males. While significant increases in stature from the Jomon to the Yayoi period were found in both males and females, no significant changes in body mass were seen. The correlation coefficients between true and false pelvic measurements (maximum pelvic height and maximum pelvic breadth) and body size (stature and body mass) suggested few significant relationships between true and false pelvic measurements or body size among the samples, but no significant correlations in small-bodied Jomon females. Results of principal component analysis using the log-size and log-shape variables suggested that the true pelvic size in Jomon and Yayoi females was not correlated with their general pelvic or body size, and there were correlations between sexually dimorphic aspects of true pelvis shape and either the false pelvis or body size in males but not females. CONCLUSIONS These results suggest that the obstetrical dimensions in small-bodied Jomon females were maintained for obstetric needs.
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Affiliation(s)
- Hirofumi Takamuku
- The Doigahama Site Anthropological Museum, Shimonoseki City, Yamaguchi, Japan
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35
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VanSickle C, Cofran Z, García-Martínez D, Williams SA, Churchill SE, Berger LR, Hawks J. Homo naledi pelvic remains from the Dinaledi Chamber, South Africa. J Hum Evol 2018; 125:122-136. [DOI: 10.1016/j.jhevol.2017.10.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 09/27/2017] [Accepted: 10/03/2017] [Indexed: 11/30/2022]
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36
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Beresheim AC, Pfeiffer SK, Alblas A. The Influence of Body Size and Bone Mass on Cortical Bone Histomorphometry in Human Ribs. Anat Rec (Hoboken) 2018; 301:1788-1796. [DOI: 10.1002/ar.23933] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/14/2018] [Accepted: 01/17/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Amy C. Beresheim
- Department of Anthropology; University of Toronto; Toronto Ontario Canada
| | - Susan K. Pfeiffer
- Department of Anthropology; University of Toronto; Toronto Ontario Canada
- Department of Archaeology; University of Cape Town; Rondebosch South Africa
| | - Amanda Alblas
- Division of Anatomy and Histology, Department of Biomedical Sciences; Faculty of Medicine and Health Sciences, Stellenbosch University; Cape Town South Africa
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37
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Torres-Tamayo N, García-Martínez D, Nalla S, Barash A, Williams SA, Blanco-Pérez E, Mata Escolano F, Sanchis-Gimeno JA, Bastir M. The torso integration hypothesis revisited in Homo sapiens: Contributions to the understanding of hominin body shape evolution. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 167:777-790. [PMID: 30259957 DOI: 10.1002/ajpa.23705] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 08/04/2018] [Accepted: 08/09/2018] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Lower thoracic widths and curvatures track upper pelvic widths and iliac blades curvatures in hominins and other primates (torso integration hypothesis). However, recent studies suggest that sexual dimorphism could challenge this assumption in Homo sapiens. We test the torso integration hypothesis in two modern human populations, both considering and excluding the effect of sexual dimorphism. We further assess covariation patterns between different thoracic and pelvic levels, and we explore the allometric effects on torso shape variation. MATERIAL AND METHODS A sex-balanced sample of 50 anatomically connected torsos (25 Mediterraneans, 25 Sub-Saharan Africans) was segmented from computed tomography scans. We compared the maximum medio-lateral width at seventh-ninth rib levels with pelvic bi-iliac breadth in males and females within both populations. We measured 1,030 (semi)landmarks on 3D torso models, and torso shape variation, mean size and shape comparisons, thoraco-pelvic covariation and allometric effects were quantified through 3D geometric morphometrics. RESULTS Females show narrow thoraces and wide pelves and males show wide thoraces and narrow pelves, although this trend is more evident in Mediterraneans than in Sub-Saharans. Equal thoracic and pelvic widths, depths and curvatures were found in absence of sexual dimorphism. The highest strength of covariation was found between the lowest rib levels and the ilia, and allometric analyses showed that smaller torsos were wider than larger torsos. CONCLUSIONS This is the first study testing statistically the torso integration hypothesis in anatomically connected torsos. We propose a new and more complex torso integration model in H. sapiens with sexual dimorphism leading to different thoracic and pelvic widths and curvatures. These findings have important implications in hominin body shape reconstructions.
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Affiliation(s)
| | | | - Shahed Nalla
- Department of Human Anatomy and Physiology, Faculty of Health Sciences, University of Johannesburg, Johannesburg, South Africa.,Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Alon Barash
- Faculty of Medicine, Bar-Ilan University, Ramat Gan, Israel
| | - Scott A Williams
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand, Johannesburg, South Africa.,Center for the Study of Human Origins, Department of Anthropology, New York University, New York, New York.,New York Consortium in Evolutionary Primatology, New York, New York
| | | | - Federico Mata Escolano
- CT and MRI Unit, ERESA, Department of Radiology, General University Hospital, Valencia, Spain
| | - Juan Alberto Sanchis-Gimeno
- Department of Radiology, Hospital de La Ribera, Valencia, Spain.,Department of Anatomy and Human Embryology, Faculty of Medicine, University of Valencia, Valencia, Spain
| | - Markus Bastir
- Paleoanthropology Group, Museo Nacional de Ciencias Naturales, Madrid, Spain
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38
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Delprete H. Pelvic Inlet Shape Is Not as Dimorphic as Previously Suggested. Anat Rec (Hoboken) 2017; 300:706-715. [PMID: 28297189 DOI: 10.1002/ar.23544] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 11/07/2016] [Accepted: 12/06/2016] [Indexed: 12/15/2022]
Abstract
It is well known that there are significant differences in the pelves of males and females due, in part, to differing constraints. The male and female pelves must be suitable for upright posture and locomotion, but the female pelvis must also be suitable for reproduction. These differing requirements lead to differences in the shape and size of various pelvic dimensions. These differences are reflected in the pelvic inlet, midplane, and outlet. Current research has documented dimorphisms in the posterior and anterior spaces in all three of these planes. One measure however, that is calculated from the relationship between the length of the anterior-posterior diameter (APD) and the transverse diameter (TD) of the inlet, is not as dimorphic as previously suggested. This computed value is used to describe four main categories of inlet shape: android, gynecoid, anthropoid, and platypelloid. Current textbooks in anatomy and midwifery describe these forms and identify the typical male inlet shape as android and the typical female inlet shape as gynecoid. In this study, however, using skeletonized pelves of 378 adult individuals from three identified skeletal collections, the most common inlet shape for both males and females was android. In addition, when examining shape as a continuous variable, inlet shape is not sexually dimorphic in two of the three populations examined in this study. Based on the results of this study, the inlet shape for males and females is less dimorphic than previously thought, and we need to discontinue using pelvic categories to describe typical inlet shape. Anat Rec, 300:706-715, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Hillary Delprete
- Department of History and Anthropology, Monmouth University, Long Branch, New Jersey
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39
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Wall-Scheffler CM, Myers MJ. The Biomechanical and Energetic Advantages of a Mediolaterally Wide Pelvis in Women. Anat Rec (Hoboken) 2017; 300:764-775. [PMID: 28297181 DOI: 10.1002/ar.23553] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 08/15/2016] [Accepted: 10/14/2016] [Indexed: 12/22/2022]
Abstract
Here, we argue that two key shifts in thinking are required to more clearly understand the selection pressures shaping pelvis evolution in female hominins: (1) the primary locomotor mode of female hominins was loaded walking in the company of others, and (2) the periodic gait of human walking is most effectively explained as a biomechanically controlled process related to heel-strike collisions that is tuned for economy and stability by properly-timed motor inputs (a model called dynamic walking). In the light of these two frameworks, the evidence supports differences between female and male upper-pelvic morphology being the result of the unique reproductive role of female hominins, which involved moderately paced, loaded walking in groups. Anat Rec, 300:764-775, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Cara M Wall-Scheffler
- Department of Anthropology, University of Washington, Seattle, Washington.,Department of Biology, Seattle Pacific University, Seattle, Washington
| | - Marcella J Myers
- Department of Biology, St. Catherine University, St. Paul Campus, St. Paul, Minnesota
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40
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Shirley MK, Cole TJ, Charoensiriwath S, Treleaven P, Wells JC. Differential investment in body girths by sex: Evidence from 3D photonic scanning in a Thai cohort. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 163:696-706. [DOI: 10.1002/ajpa.23238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 03/21/2017] [Accepted: 04/16/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Meghan K. Shirley
- UCL Great Ormond Street Institute of Child Health; London WC1N 1EH United Kingdom
| | - Tim J. Cole
- UCL Great Ormond Street Institute of Child Health; London WC1N 1EH United Kingdom
| | | | - Philip Treleaven
- UCL Great Ormond Street Institute of Child Health; London WC1N 1EH United Kingdom
| | - Jonathan C.K. Wells
- UCL Great Ormond Street Institute of Child Health; London WC1N 1EH United Kingdom
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41
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Moffett EA. Dimorphism in the Size and Shape of the Birth Canal Across Anthropoid Primates. Anat Rec (Hoboken) 2017; 300:870-889. [DOI: 10.1002/ar.23572] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 09/13/2016] [Accepted: 12/19/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Elizabeth A. Moffett
- Department of Pathology and Anatomical Sciences; University of Missouri; Columbia Missouri
- Department of Anthropology; Stony Brook University; Stony Brook New York
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42
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Lewis CL, Laudicina NM, Khuu A, Loverro KL. The Human Pelvis: Variation in Structure and Function During Gait. Anat Rec (Hoboken) 2017; 300:633-642. [PMID: 28297184 PMCID: PMC5545133 DOI: 10.1002/ar.23552] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 10/19/2016] [Accepted: 12/19/2016] [Indexed: 11/07/2022]
Abstract
The shift to habitual bipedalism 4-6 million years ago in the hominin lineage created a morphologically and functionally different human pelvis compared to our closest living relatives, the chimpanzees. Evolutionary changes to the shape of the pelvis were necessary for the transition to habitual bipedalism in humans. These changes in the bony anatomy resulted in an altered role of muscle function, influencing bipedal gait. Additionally, there are normal sex-specific variations in the pelvis as well as abnormal variations in the acetabulum. During gait, the pelvis moves in the three planes to produce smooth and efficient motion. Subtle sex-specific differences in these motions may facilitate economical gait despite differences in pelvic structure. The motions of the pelvis and hip may also be altered in the presence of abnormal acetabular structure, especially with acetabular dysplasia. Anat Rec, 300:633-642, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Cara L. Lewis
- Department of Physical Therapy & Athletic Training, Boston University, Boston, MA, USA
| | | | - Anne Khuu
- Department of Physical Therapy & Athletic Training, Boston University, Boston, MA, USA
| | - Kari L. Loverro
- Department of Physical Therapy & Athletic Training, Boston University, Boston, MA, USA
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43
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Fischer B, Mitteroecker P. Allometry and Sexual Dimorphism in the Human Pelvis. Anat Rec (Hoboken) 2017; 300:698-705. [DOI: 10.1002/ar.23549] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 09/30/2016] [Accepted: 10/20/2016] [Indexed: 01/11/2023]
Affiliation(s)
- Barbara Fischer
- Konrad Lorenz Institute for Evolution and Cognition Research; Martinstrasse 12 Klosterneuburg 3400 Austria
- Department of Theoretical Biology; University of Vienna; Althanstrasse 14 Wien 1090 Austria
| | - Philipp Mitteroecker
- Department of Theoretical Biology; University of Vienna; Althanstrasse 14 Wien 1090 Austria
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44
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Whitcome KK, Miller EE, Burns JL. Pelvic Rotation Effect on Human Stride Length: Releasing the Constraint of Obstetric Selection. Anat Rec (Hoboken) 2017; 300:752-763. [DOI: 10.1002/ar.23551] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 08/01/2016] [Accepted: 10/09/2016] [Indexed: 11/07/2022]
Affiliation(s)
| | | | - Jessica L. Burns
- Department of Anthropology; University of Utah; Salt Lake City Utah 84112
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45
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Mahakkanukrauh P, Ruengdit S, Tun SM, Case DT, Sinthubua A. Osteometric sex estimation from the os coxa in a Thai population. Forensic Sci Int 2016; 271:127.e1-127.e7. [PMID: 28062152 DOI: 10.1016/j.forsciint.2016.11.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 11/29/2016] [Accepted: 11/30/2016] [Indexed: 11/29/2022]
Abstract
The coxal bone shows a very high degree of sexual dimorphism both morphologically and metrically. However, despite a number of recent studies on sex estimation from the skeleton in Thailand, no osteometric methods of sexing the Thai os coxa have been proposed. Therefore, the aim of this study was to develop a standard sex estimation method for a Thai population by examining the efficacy of six coxal bone measurements and eight indices obtained from 200 Thai skeletons. Independent samples t-tests revealed statistically significant differences between males and females for all but one of the measurements. The equation with the highest correct allocation accuracy was based on four measurements (pubis length, ischium length, total height and acetabulum diameter) and had a predicted and cross-validated accuracy of 96.9% and a tested accuracy of 97.5% on a holdout sample of 40 individuals. The single variable equation with the highest correct allocation accuracy of 94.4% and a tested accuracy of 97.5% was for the ischiopubic index, which is calculated from ischium length and pubis length. Percentage accuracies in predicting sex from these equations were higher than many previous studies, suggesting high levels of sexual dimorphism in the Thai os coxa.
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Affiliation(s)
- Pasuk Mahakkanukrauh
- Forensic Osteology Research Center, Faculty of Medicine, Chiang Mai University, 50200, Thailand; Excellence in Osteology Research and Training Center (ORTC), Chiang Mai University, Chiang Mai, 50200, Thailand; Department of Anatomy, Faculty of Medicine, Chiang Mai University, 50200, Thailand.
| | - Sittiporn Ruengdit
- Forensic Osteology Research Center, Faculty of Medicine, Chiang Mai University, 50200, Thailand.
| | - Saw Myint Tun
- Forensic Science Graduate Programme, Faculty of Science, Mahidol University, 10200, Thailand.
| | - D Troy Case
- Department of Sociology & Anthropology, NC State University, Campus Box 8107, Raleigh, NC 27695-8107, USA.
| | - Apichat Sinthubua
- Forensic Osteology Research Center, Faculty of Medicine, Chiang Mai University, 50200, Thailand; Excellence in Osteology Research and Training Center (ORTC), Chiang Mai University, Chiang Mai, 50200, Thailand; Department of Anatomy, Faculty of Medicine, Chiang Mai University, 50200, Thailand.
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46
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Claxton AG, Hammond AS, Romano J, Oleinik E, DeSilva JM. Virtual reconstruction of the Australopithecus africanus pelvis Sts 65 with implications for obstetrics and locomotion. J Hum Evol 2016; 99:10-24. [DOI: 10.1016/j.jhevol.2016.06.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 03/05/2016] [Accepted: 06/03/2016] [Indexed: 11/28/2022]
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47
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Tobolsky VA, Kurki HK, Stock JT. Patterns of directional asymmetry in the pelvis and pelvic canal. Am J Hum Biol 2016; 28:804-810. [PMID: 27224219 DOI: 10.1002/ajhb.22870] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Revised: 03/18/2016] [Accepted: 05/01/2016] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES The human pelvis is unique among modern taxa for supporting both parturition of large brained young and obligate bipedalism. Though much work has focused on pelvic development and variation, little work has explored the presence or absence of asymmetry in the pelvis despite well-known patterns of asymmetry in other skeletal regions. This study investigated whether patterns of directional asymmetry (DA) could be observed in the pelvis or pelvic canal. METHODS Seventeen bilaterally paired osteometric measurements of the os coxae (34 measures in total) were taken from 128 skeletons (female n = 65, male n = 63) from recent human populations in five geographic regions. Paired sample t-tests and Mann-Whitney U-tests were used to investigate DA. RESULTS Results from a pooled sample of all individuals showed that the pelvis exhibited a left-bias in DA. In contrast, the pelvic canal exhibited a pattern in which the anterior canal exhibited a right-bias and the posterior canal exhibited a left-bias. Neither sex nor populational differences in DA were observed in the pelvis or pelvic canal. CONCLUSIONS The varying patterns of asymmetry uncovered here accord with prior work and may indicate that loading from the trunk and legs place differing stresses on the pelvis and canal, yielding these unequal asymmetries. However, this is speculative and the possible influence of genetics, biomechanics, and nutritional status on the development of pelvic and canal asymmetries presents a rich area for future study. Additionally, the potential influence of pelvic canal asymmetry on obstetric measures of pelvic capacity merits future research. Am. J. Hum. Biol. 28:804-810, 2016. © 2016Wiley Periodicals, Inc.
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Affiliation(s)
- Victoria A Tobolsky
- Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, UK.,Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, 02138
| | - Helen K Kurki
- Department of Anthropology, University of Victoria, Victoria, British Columbia, Canada, V8W 3P5
| | - Jay T Stock
- Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, UK
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48
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Developmental evidence for obstetric adaptation of the human female pelvis. Proc Natl Acad Sci U S A 2016; 113:5227-32. [PMID: 27114515 DOI: 10.1073/pnas.1517085113] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The bony pelvis of adult humans exhibits marked sexual dimorphism, which is traditionally interpreted in the framework of the "obstetrical dilemma" hypothesis: Giving birth to large-brained/large-bodied babies requires a wide pelvis, whereas efficient bipedal locomotion requires a narrow pelvis. This hypothesis has been challenged recently on biomechanical, metabolic, and biocultural grounds, so that it remains unclear which factors are responsible for sex-specific differences in adult pelvic morphology. Here we address this issue from a developmental perspective. We use methods of biomedical imaging and geometric morphometrics to analyze changes in pelvic morphology from late fetal stages to adulthood in a known-age/known-sex forensic/clinical sample. Results show that, until puberty, female and male pelves exhibit only moderate sexual dimorphism and follow largely similar developmental trajectories. With the onset of puberty, however, the female trajectory diverges substantially from the common course, resulting in rapid expansion of obstetrically relevant pelvic dimensions up to the age of 25-30 y. From 40 y onward females resume a mode of pelvic development similar to males, resulting in significant reduction of obstetric dimensions. This complex developmental trajectory is likely linked to the pubertal rise and premenopausal fall of estradiol levels and results in the obstetrically most adequate pelvic morphology during the time of maximum female fertility. The evidence that hormones mediate female pelvic development and morphology supports the view that solutions of the obstetrical dilemma depend not only on selection and adaptation but also on developmental plasticity as a response to ecological/nutritional factors during a female's lifetime.
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49
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Do patterns of covariation between human pelvis shape, stature, and head size alleviate the obstetric dilemma? Proc Natl Acad Sci U S A 2016; 113:E258. [PMID: 26755595 DOI: 10.1073/pnas.1517524113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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50
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Gruss LT, Schmitt D. The evolution of the human pelvis: changing adaptations to bipedalism, obstetrics and thermoregulation. Philos Trans R Soc Lond B Biol Sci 2016; 370:20140063. [PMID: 25602067 DOI: 10.1098/rstb.2014.0063] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The fossil record of the human pelvis reveals the selective priorities acting on hominin anatomy at different points in our evolutionary history, during which mechanical requirements for locomotion, childbirth and thermoregulation often conflicted. In our earliest upright ancestors, fundamental alterations of the pelvis compared with non-human primates facilitated bipedal walking. Further changes early in hominin evolution produced a platypelloid birth canal in a pelvis that was wide overall, with flaring ilia. This pelvic form was maintained over 3-4 Myr with only moderate changes in response to greater habitat diversity, changes in locomotor behaviour and increases in brain size. It was not until Homo sapiens evolved in Africa and the Middle East 200 000 years ago that the narrow anatomically modern pelvis with a more circular birth canal emerged. This major change appears to reflect selective pressures for further increases in neonatal brain size and for a narrow body shape associated with heat dissipation in warm environments. The advent of the modern birth canal, the shape and alignment of which require fetal rotation during birth, allowed the earliest members of our species to deal obstetrically with increases in encephalization while maintaining a narrow body to meet thermoregulatory demands and enhance locomotor performance.
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Affiliation(s)
| | - Daniel Schmitt
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
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