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Lukova A, Dunmore CJ, Bachmann S, Synek A, Pahr DH, Kivell TL, Skinner MM. Trabecular architecture of the distal femur in extant hominids. J Anat 2024; 245:156-180. [PMID: 38381116 PMCID: PMC11161831 DOI: 10.1111/joa.14026] [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: 07/10/2023] [Revised: 02/01/2024] [Accepted: 02/05/2024] [Indexed: 02/22/2024] Open
Abstract
Extant great apes are characterized by a wide range of locomotor, postural and manipulative behaviours that each require the limbs to be used in different ways. In addition to external bone morphology, comparative investigation of trabecular bone, which (re-)models to reflect loads incurred during life, can provide novel insights into bone functional adaptation. Here, we use canonical holistic morphometric analysis (cHMA) to analyse the trabecular morphology in the distal femoral epiphysis of Homo sapiens (n = 26), Gorilla gorilla (n = 14), Pan troglodytes (n = 15) and Pongo sp. (n = 9). We test two predictions: (1) that differing locomotor behaviours will be reflected in differing trabecular architecture of the distal femur across Homo, Pan, Gorilla and Pongo; (2) that trabecular architecture will significantly differ between male and female Gorilla due to their different levels of arboreality but not between male and female Pan or Homo based on previous studies of locomotor behaviours. Results indicate that trabecular architecture differs among extant great apes based on their locomotor repertoires. The relative bone volume and degree of anisotropy patterns found reflect habitual use of extended knee postures during bipedalism in Homo, and habitual use of flexed knee posture during terrestrial and arboreal locomotion in Pan and Gorilla. Trabecular architecture in Pongo is consistent with a highly mobile knee joint that may vary in posture from extension to full flexion. Within Gorilla, trabecular architecture suggests a different loading of knee in extension/flexion between females and males, but no sex differences were found in Pan or Homo, supporting our predictions. Inter- and intra-specific variation in trabecular architecture of distal femur provides a comparative context to interpret knee postures and, in turn, locomotor behaviours in fossil hominins.
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Affiliation(s)
- Andrea Lukova
- Skeletal Biology Research Centre, School of Anthropology and ConservationUniversity of KentCanterburyUK
| | - Christopher J. Dunmore
- Skeletal Biology Research Centre, School of Anthropology and ConservationUniversity of KentCanterburyUK
| | - Sebastian Bachmann
- Institute of Lightweight Design and Structural BiomechanicsTU WienWienAustria
| | - Alexander Synek
- Institute of Lightweight Design and Structural BiomechanicsTU WienWienAustria
| | - Dieter H. Pahr
- Institute of Lightweight Design and Structural BiomechanicsTU WienWienAustria
- Department of Anatomy and Biomechanics, Division BiomechanicsKarl Landsteiner University of Health SciencesKremsAustria
| | - Tracy L. Kivell
- Department of Human OriginsMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Matthew M. Skinner
- Department of Human OriginsMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
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2
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Korpinen N. Differences in vertebral bone density between African apes. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024; 184:e24937. [PMID: 38644542 DOI: 10.1002/ajpa.24937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/08/2024] [Accepted: 04/02/2024] [Indexed: 04/23/2024]
Abstract
OBJECTIVES Low-energy vertebral fractures are a common health concern, especially in elderly people. Interestingly, African apes do not seem to experience as many vertebral fractures and the low-energy ones are even rarer. One potential explanation for this difference is the lower bone density in humans. Yet, only limited research has been done on the vertebral bone density of the great apes and these have mainly included only single vertebrae. Hence the study aim is to expand our understanding of the vertebral microstructure of African apes in multiple spinal segments. MATERIALS Bone density in the vertebral body of C7, T12, and L3 was measured from 32 Pan troglodytes and 26 Gorilla gorilla using peripheral quantitative computed tomography (pQCT). RESULTS There was a clear difference between the three individual vertebrae and consequently the spinal segments in terms of trabecular density and cortical density and thickness. The variation of these bone parameters between the vertebrae differed between the apes but was also different from those reported for humans. The chimpanzees were observed to have overall higher trabecular density, but gorillas had higher cortical density and thickness. Cortical thickness had a relatively strong association with the vertebral size. DISCUSSION Despite the similarity in locomotion and posture, the results show slight differences in the bone parameters and their variation between spinal segments in African apes. This variation also differs from humans and appears to indicate a complex influence of locomotion, posture, and body size on the different spinal segments.
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Affiliation(s)
- Niina Korpinen
- Department of Archaeology, Faculty of Humanities, University of Oulu, Oulu, Finland
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3
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Vanhoof MJM, Galletta L, De Groote I, Vereecke EE. Covariation between wrist bone morphology and maximal range of motion during ulnar deviation and supination in extant nonhuman primate taxa. J Exp Biol 2023; 226:jeb245906. [PMID: 37665264 DOI: 10.1242/jeb.245906] [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: 04/12/2023] [Accepted: 08/16/2023] [Indexed: 09/05/2023]
Abstract
This study investigates the maximal range of motion (ROM) during wrist deviation and forearm rotation for five different primate genera and the possible correlation with the shape of the distal ulna, triquetrum and hamate. A two-block phylogenetic partial least square analysis was performed to test this covariation in a phylogenetic context, using shape coordinates and a matrix of maximal ROM data as input data. The results show that gibbons have the highest ROM for both ulnar deviation and supination, whereas Macaca exhibited the lowest ROM for supination, and Pan had the lowest ROM for ulnar deviation. These results can be attributed to differences in locomotor behaviour, as gibbons need a large wrist mobility in all directions for their highly arboreal lifestyle, whereas Macaca and Pan need a stable wrist during terrestrial locomotion. However, we found no correlation between distal ulna/triquetrum/hamate shape and maximal ROM during ulnar deviation and supination in the different primate taxa. A larger dataset, in combination with behavioural and biomechanical studies, is needed to establish form-function relationships of the primate hand, which will aid the functional interpretation of primate fossil remains.
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Affiliation(s)
- Marie J M Vanhoof
- Department of Development & Regeneration, Biomedical Sciences Group, KU Leuven Campus Kulak, 8500 Kortrijk, Belgium
| | - Lorenzo Galletta
- School of Life and Environmental Sciences, Deakin University, 3216 Waurn Pounds, Victoria, Australia
| | - Isabelle De Groote
- Department of Archaeology, Ghent University, 9000 Ghent, Belgium
- Research Centre in Evolutionary Anthropology and Paleoecology, Liverpool John Moores University, Liverpool L2 2QP, UK
| | - Evie E Vereecke
- Department of Development & Regeneration, Biomedical Sciences Group, KU Leuven Campus Kulak, 8500 Kortrijk, Belgium
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Meyer MR, Jung JP, Spear JK, Araiza IF, Galway-Witham J, Williams SA. Knuckle-walking in Sahelanthropus? Locomotor inferences from the ulnae of fossil hominins and other hominoids. J Hum Evol 2023; 179:103355. [PMID: 37003245 DOI: 10.1016/j.jhevol.2023.103355] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 03/03/2023] [Accepted: 03/03/2023] [Indexed: 04/03/2023]
Abstract
Because the ulna supports and transmits forces during movement, its morphology can signal aspects of functional adaptation. To test whether, like extant apes, some hominins habitually recruit the forelimb in locomotion, we separate the ulna shaft and ulna proximal complex for independent shape analyses via elliptical Fourier methods to identify functional signals. We examine the relative influence of locomotion, taxonomy, and body mass on ulna contours in Homo sapiens (n = 22), five species of extant apes (n = 33), two Miocene apes (Hispanopithecus and Danuvius), and 17 fossil hominin specimens including Sahelanthropus, Ardipithecus, Australopithecus, Paranthropus, and early Homo. Ulna proximal complex contours correlate with body mass but not locomotor patterns, while ulna shafts significantly correlate with locomotion. African apes' ulna shafts are more robust and curved than Asian apes and are unlike other terrestrial mammals (including other primates), curving ventrally rather than dorsally. Because this distinctive curvature is absent in orangutans and hylobatids, it is likely a function of powerful flexors engaged in wrist and hand stabilization during knuckle-walking, and not an adaptation to climbing or suspensory behavior. The OH 36 (purported Paranthropus boisei) and TM 266 (assigned to Sahelanthropus tchadensis) fossils differ from other hominins by falling within the knuckle-walking morphospace, and thus appear to show forelimb morphology consistent with terrestrial locomotion. Discriminant function analysis classifies both OH 36 and TM 266 with Pan and Gorilla with high posterior probability. Along with its associated femur, the TM 266 ulna shaft contours and its deep, keeled trochlear notch comprise a suite of traits signaling African ape-like quadrupedalism. While implications for the phylogenetic position and hominin status of S. tchadensis remain equivocal, this study supports the growing body of evidence indicating that S. tchadensis was not an obligate biped, but instead represents a late Miocene hominid with knuckle-walking adaptations.
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Affiliation(s)
- Marc R Meyer
- Department of Anthropology, Chaffey College, Rancho Cucamonga, CA 91737, USA.
| | - Jason P Jung
- Department of Biology, California State University, San Bernardino, CA 92407, USA
| | - Jeffrey K Spear
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA; New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
| | - Isabella Fx Araiza
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA; New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
| | - Julia Galway-Witham
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA; New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
| | - Scott A Williams
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA; New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
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Goldstein DM, Sylvester AD. Carpal allometry of African apes among mammals. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2023; 181:10-28. [PMID: 36808858 DOI: 10.1002/ajpa.24716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 01/13/2023] [Accepted: 02/06/2023] [Indexed: 02/20/2023]
Abstract
OBJECTIVES Morphological variation in African ape carpals has been used to support the idea that Pan and Gorilla evolved knuckle-walking independently. Little work, however, has focused on the effect of body mass on carpal morphology. Here, we compare carpal allometry in Pan and Gorilla to that of other quadrupedal mammals with similar body mass differences. If allometric trends in Pan and Gorilla carpals mirror those of other mammals with similar body mass variation, then body mass differences may provide a more parsimonious explanation for African ape carpal variation than the independent evolution of knuckle-walking. MATERIALS AND METHODS Three linear measurements were collected on the capitate, hamate, lunate, and scaphoid (or scapholunate) of 39 quadrupedal species from six mammalian families/subfamilies. Relationships between linear measurements and estimated body mass were analyzed using reduced major axis regression. Slopes were compared to 0.33 for isometry. RESULTS Within Hominidae, higher body mass taxa (Gorilla) have relatively anteroposteriorly wider, mediolaterally wider, and/or proximodistally shorter capitates, hamates, and scaphoids than low body mass taxa (Pan). These allometric relationships are mirrored in most, but not all, mammalian families/subfamilies included in the analysis. CONCLUSIONS Within most mammalian families/subfamilies, carpals of high body mass taxa are proximodistally shorter, anteroposteriorly wider, and mediolaterally wider than those of low body mass taxa. These distinctions may be caused by the need to accommodate relatively higher forelimb loading associated with greater body mass. Because these trends occur within multiple mammalian families/subfamilies, some carpal variation in Pan and Gorilla is consistent with body mass differences.
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Affiliation(s)
- Deanna M Goldstein
- Department of Anatomical Sciences, Renaissance School of Medicine at Stony Brook University, Stony Brook, New York, USA
| | - Adam D Sylvester
- Center for Functional Anatomy and Evolution, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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6
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Figus C, Stephens NB, Sorrentino R, Bortolini E, Arrighi S, Higgins OA, Lugli F, Marciani G, Oxilia G, Romandini M, Silvestrini S, Baruffaldi F, Belcastro MG, Bernardini F, Festa A, Hajdu T, Mateovics‐László O, Pap I, Szeniczey T, Tuniz C, Ryan TM, Benazzi S. Morphologies in-between: The impact of the first steps on the human talus. Anat Rec (Hoboken) 2023; 306:124-142. [PMID: 35656925 PMCID: PMC10083965 DOI: 10.1002/ar.25010] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 01/29/2023]
Abstract
OBJECTIVE The development of bipedalism is a very complex activity that contributes to shaping the anatomy of the foot. The talus, which starts ossifying in utero, may account for the developing stages from the late gestational phase onwards. Here, we explore the early development of the talus in both its internal and external morphology to broaden the knowledge of the anatomical changes that occur during early development. MATERIALS AND METHODS The sample consists of high-resolution microCT scans of 28 modern juvenile tali (from 36 prenatal weeks to 2 years), from a broad chronological range from the Late Roman period to the 20th century. We applied geometric morphometric and whole-bone trabecular analysis to investigate the early talar morphological changes. RESULTS In the youngest group (<6 postnatal months), the immature external shell is accompanied by an isotropic internal structure, with thin and densely packed trabeculae. After the initial attempts of locomotion, bone volume fraction decreases, while anisotropy and trabecular thickness increase. These internal changes correspond to the maturation of the external shell, which is now more defined and shows the development of the articular surfaces. DISCUSSION The internal and external morphology of the human talus reflects the diverse load on the foot during the initial phases of the bipedal locomotion, with the youngest group potentially reflecting the lack of readiness of the human talus to bear forces and perform bipedal walking. These results highlight the link between mechanical loading and bone development in the human talus during the acquisition of bipedalism, providing new insight into the early phases of talar development.
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Affiliation(s)
- Carla Figus
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Nicholas B. Stephens
- Department of AnthropologyPennsylvania State UniversityState CollegePennsylvaniaUSA
| | - Rita Sorrentino
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
- Department of Biological, Geological and Environmental Sciences – BigeaUniversity of BolognaBolognaItaly
| | - Eugenio Bortolini
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
- Human Ecology and Archaeology (HUMANE)IMF, CSI0CBarcelonaSpain
| | - Simona Arrighi
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Owen A. Higgins
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Federico Lugli
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Giulia Marciani
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
- Research Unit Prehistory and Anthropology, Department of Physical Sciences, Earth and EnvironmentUniversity of SienaSienaItaly
| | - Gregorio Oxilia
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Matteo Romandini
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Sara Silvestrini
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
| | - Fabio Baruffaldi
- Laboratory of Medical TechnologyIRCCS Istituto Ortopedico RizzoliBolognaItaly
| | - Maria Giovanna Belcastro
- Department of Biological, Geological and Environmental Sciences – BigeaUniversity of BolognaBolognaItaly
| | - Federico Bernardini
- Department of Humanistic StudiesUniversità Ca'FoscariVeneziaItaly
- Multidisciplinary LaboratoryAbdus Salam International Centre for Theoretical PhysicsTriesteItaly
| | - Anna Festa
- Laboratory of Medical TechnologyIRCCS Istituto Ortopedico RizzoliBolognaItaly
| | - Tamás Hajdu
- Department of Biological Anthropology, Institute of Biology, Faculty of ScienceEötvös Loránd UniversityBudapestHungary
| | | | - Ildiko Pap
- Department of Biological Anthropology, Institute of Biology, Faculty of ScienceEötvös Loránd UniversityBudapestHungary
- Department of Biological Anthropology, Institute of Biology, Faculty of Science and InformaticsSzeged UniversitySzegedHungary
- Department of AnthropologyHungarian Natural History MuseumBudapestHungary
| | - Tamás Szeniczey
- Department of Biological Anthropology, Institute of Biology, Faculty of ScienceEötvös Loránd UniversityBudapestHungary
| | - Claudio Tuniz
- Multidisciplinary LaboratoryAbdus Salam International Centre for Theoretical PhysicsTriesteItaly
- Centre for Archaeological ScienceUniversity of WollongongWollongongNew South WalesAustralia
| | - Timothy M. Ryan
- Department of AnthropologyPennsylvania State UniversityState CollegePennsylvaniaUSA
| | - Stefano Benazzi
- Department of Cultural HeritageUniversity of BolognaRavennaItaly
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
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7
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D’Antona G, Burtscher M. Muscle endurance: Is bipedalism the cause? Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.1067396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
One may ask if the transition to bipedalism from the condition of quadrupedalism, which occurred about 7 million years ago, has been the cause or consequence of a series of fundamental physiological muscular aspects including the cost of locomotion, a crucial determinant of endurance, which has been found to be significantly lower in humans than in apes. This issue strictly links to unsolved issues regarding the significance of several muscular structural and functional adaptations, classically attributed to bipedalism and its associated locomotions, which we cannot simply attribute to the acquisition of the upright position and which may directly or indirectly contribute to the observed changes in muscle energetics that make the modern human an exceptional endurance walker and runner compared to quadrupedals.
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8
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The evolution of human step counts and its association with the risk of chronic disease. Curr Biol 2022; 32:R1206-R1214. [PMID: 36347224 DOI: 10.1016/j.cub.2022.09.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Walking - humans' most fundamental form of moderate intensity physical activity - is associated with reduced risks of morbidity and mortality. Evolutionary perspectives have contributed much to understanding the effects of walking and other physical activities on health; however, we know comparatively little about how step counts (steps taken per day) changed over the course of human evolution, potentially affecting how selection operated on physiological responses to moderate intensity physical activity that influence morbidity and mortality. Here, we compare step counts across humans and our closest living relatives, the great apes. Compiling data from epidemiology and comparative physiology, we show how step counts more than tripled during human evolution, potentially linking higher levels of moderate intensity physical activity with reduced morbidity and mortality, and we highlight how recent decreases in step counts are an evolutionary mismatch. We raise the hypothesis that the dose-response relationship between moderate intensity physical activity and health was shifted in humans to require more steps per day to promote extended healthspan and lifespan.
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Widyastuti K, Reuillon R, Chapron P, Abdussalam W, Nasir D, Harrison ME, Morrogh-Bernard H, Imron MA, Berger U. Assessing the impact of forest structure disturbances on the arboreal movement and energetics of orangutans—An agent-based modeling approach. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.983337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Agent-based models have been developed and widely employed to assess the impact of disturbances or conservation management on animal habitat use, population development, and viability. However, the direct impacts of canopy disturbance on the arboreal movement of individual primates have been less studied. Such impacts could shed light on the cascading effects of disturbances on animal health and fitness. Orangutans are an arboreal primate that commonly encounters habitat quality deterioration due to land-use changes and related disturbances such as forest fires. Forest disturbance may, therefore, create a complex stress scenario threatening orangutan populations. Due to forest disturbances, orangutans may adapt to employ more terrestrial, as opposed to arboreal, movements potentially prolonging the search for fruiting and nesting trees. In turn, this may lead to changes in daily activity patterns (i.e., time spent traveling, feeding, and resting) and available energy budget, potentially decreasing the orangutan's fitness. We developed the agent-based simulation model BORNEO (arBOReal aNimal movEment mOdel), which explicitly describes both orangutans' arboreal and terrestrial movement in a forest habitat, depending on distances between trees and canopy structures. Orangutans in the model perform activities with a motivation to balance energy intake and expenditure through locomotion. We tested the model using forest inventory data obtained in Sebangau National Park, Central Kalimantan, Indonesia. This allowed us to construct virtual forests with real characteristics including tree connectivity, thus creating the potential to expand the environmental settings for simulation experiments. In order to parameterize the energy related processes of the orangutans described in the model, we applied a computationally intensive evolutionary algorithm and evaluated the simulation results against observed behavioral patterns of orangutans. Both the simulated variability and proportion of activity budgets including feeding, resting, and traveling time for female and male orangutans confirmed the suitability of the model for its purpose. We used the calibrated model to compare the activity patterns and energy budgets of orangutans in both natural and disturbed forests . The results confirm field observations that orangutans in the disturbed forest are more likely to experience deficit energy balance due to traveling to the detriment of feeding time. Such imbalance is more pronounced in males than in females. The finding of a threshold of forest disturbances that affects a significant change in activity and energy budgets suggests potential threats to the orangutan population. Our study introduces the first agent-based model describing the arboreal movement of primates that can serve as a tool to investigate the direct impact of forest changes and disturbances on the behavior of species such as orangutans. Moreover, it demonstrates the suitability of high-performance computing to optimize the calibration of complex agent-based models describing animal behavior at a fine spatio-temporal scale (1-m and 1-s granularity).
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Sellers WI, Cross CF, Fukuhara A, Ishiguro A, Hirasaki E. Producing non-steady-state gaits (starting, stopping, and turning) in a biologically realistic quadrupedal simulation. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.954838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Multibody dynamic analysis (MDA) has become part of the standard toolkit used to reconstruct the biomechanics of extinct animals. However, its use is currently almost exclusively limited to steady state activities such as walking and running at constant velocity. If we want to reconstruct the full range of activities that a given morphology can achieve then we must be able to reconstruct non-steady-state activities such as starting, stopping, and turning. In this paper we demonstrate how we can borrow techniques from the robotics literature to produce gait controllers that allow us to generate non-steady-state gaits in a biologically realistic quadrupedal simulation of a chimpanzee. We use a novel proportional-derivative (PD) reach controller that can accommodate both the non-linear contraction dynamics of Hill-type muscles and the large numbers of both single-joint and two-joint muscles to allow us to define the trajectory of the distal limb segment. With defined autopodial trajectories we can then use tegotae style locomotor controllers that use decentralized reaction force feedback to control the trajectory speed in order to produce quadrupedal gait. This combination of controllers can generate starting, stopping, and turning kinematics, something that we believe has never before been achieved in a simulation that uses both physiologically realistic muscles and a high level of anatomical fidelity. The gait quality is currently relatively low compared to the more commonly used feedforward control methods, but this can almost certainly be improved in future by using more biologically based foot trajectories and increasing the complexity of the underlying model and controllers. Understanding these more complex gaits is essential, particularly in fields such as paleoanthropology where the transition from an ancestral hominoid with a diversified repertoire to a bipedal hominin is of such fundamental importance, and this approach illustrates one possible avenue for further research in this area.
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11
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Granatosky MC, Toussaint SLD, Young MW, Panyutina A, Youlatos D. The northern treeshrew (Scandentia: Tupaiidae: Tupaia belangeri) in the context of primate locomotor evolution: A comprehensive analysis of gait, positional, and grasping behavior. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:645-665. [PMID: 35451573 DOI: 10.1002/jez.2597] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/25/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
The locomotor behaviors of treeshrews are often reported as scurrying "squirrel-like" movements. As such, treeshrews have received little attention beyond passing remarks in regard to primate locomotor evolution. However, scandentians vary considerably in habitat and substrate use, thus categorizing all treeshrew locomotion based on data collected from a single species is inappropriate. This study presents data on gait characteristics, positional, and grasping behavior of the northern treeshrew (Tupaia belangeri) and compares these findings to the fat-tailed dwarf lemur (Cheirogaleus medius) to assess the role of treeshrews as a model for understanding the origins of primate locomotor and grasping evolution. We found that northern treeshrews were primarily arboreal and shared their activities between quadrupedalism, climbing and leaping in rates similar to fat-tailed dwarf lemurs. During quadrupedal locomotion, they exhibited a mixture of gait characteristics consistent with primates and other small-bodied non-primate mammals and demonstrated a hallucal grasping mode consistent with primates. These data reveal that northern treeshrews show a mosaic of primitive mammalian locomotor characteristics paired with derived primate features. Further, this study raises the possibility that many of the locomotor and grasping characteristics considered to be "uniquely" primate may ultimately be features consistent with Euarchonta.
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Affiliation(s)
- Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | | | - Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Aleksandra Panyutina
- Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russian Federation
| | - Dionisios Youlatos
- Department of Zoology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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12
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Calcar femorale variation in extant and fossil hominids: Implications for identifying bipedal locomotion in fossil hominins. J Hum Evol 2022; 167:103183. [DOI: 10.1016/j.jhevol.2022.103183] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 03/04/2022] [Accepted: 03/10/2022] [Indexed: 11/21/2022]
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13
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Assessing chimpanzees’ fluency of movement: applications for monitoring health and welfare. Appl Anim Behav Sci 2022. [DOI: 10.1016/j.applanim.2022.105612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Kraft TS, Venkataraman VV, Wallace IJ, Crittenden AN, Holowka NB, Stieglitz J, Harris J, Raichlen DA, Wood B, Gurven M, Pontzer H. The energetics of uniquely human subsistence strategies. Science 2021; 374:eabf0130. [PMID: 34941390 DOI: 10.1126/science.abf0130] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Thomas S Kraft
- Department of Anthropology, University of California, Santa Barbara, CA, USA.,Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Department of Anthropology, University of Utah, Salt Lake City, UT, USA
| | - Vivek V Venkataraman
- Institute for Advanced Study in Toulouse, Toulouse, France.,Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada
| | - Ian J Wallace
- Department of Anthropology, University of New Mexico, Albuquerque, NM, USA
| | | | | | | | - Jacob Harris
- Department of Anthropology, University of California, Los Angeles, CA, USA.,Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA
| | - David A Raichlen
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Brian Wood
- Department of Human Behavior, Ecology, and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Department of Anthropology, University of California, Los Angeles, CA, USA
| | - Michael Gurven
- Department of Anthropology, University of California, Santa Barbara, CA, USA
| | - Herman Pontzer
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA.,Duke Global Health Institute, Duke University, Durham, NC, USA
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15
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Bird EE, Kivell TL, Skinner MM. Patterns of internal bone structure and functional adaptation in the hominoid scaphoid, lunate, and triquetrum. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021. [DOI: 10.1002/ajpa.24449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Emma E. Bird
- Skeletal Biology Research Centre, School of Anthropology and Conservation University of Kent Canterbury UK
| | - Tracy L. Kivell
- Skeletal Biology Research Centre, School of Anthropology and Conservation University of Kent Canterbury UK
- Department of Human Evolution Max Planck Institute for Evolutionary Anthropology Leipzig Germany
| | - Matthew M. Skinner
- Skeletal Biology Research Centre, School of Anthropology and Conservation University of Kent Canterbury UK
- Department of Human Evolution Max Planck Institute for Evolutionary Anthropology Leipzig Germany
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16
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Arias-Martorell J, Zeininger A, Kivell TL. Trabecular structure of the elbow reveals divergence in knuckle-walking biomechanical strategies of African apes. Evolution 2021; 75:2959-2971. [PMID: 34570906 DOI: 10.1111/evo.14354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/29/2021] [Accepted: 08/03/2021] [Indexed: 01/04/2023]
Abstract
African apes engage in a distinct form of locomotion called knuckle-walking, but there is much ambiguity as to when and how this locomotor behavior evolved. This study aims to elucidate potential differences in knuckle-walking elbow posture and loading in African apes through the study of trabecular bone. Using a whole-epiphysis approach, we quantified variation in the trabecular structure of the distal humerus of chimpanzees, western lowland gorillas, and mountain gorillas in comparison to orang-utans, siamangs, and a sample of Old and New World monkeys. Results demonstrate differences in the distribution of trabecular bone within the distal humerus that are consistent across taxa that habitually use a flexed-elbow posture in comparison to those that use an extended elbow during locomotion. Western lowland gorillas show an extended-elbow pattern consistent with the straight forelimb position during knuckle-walking, whereas chimpanzees show a flexed-elbow pattern. Unexpectedly, mountain gorillas show an intermediate pattern between their western counterparts and chimpanzees. The differences found in elbow joint posture between chimpanzees and gorillas, and between gorilla species, point to diversification in the knuckle-walking biomechanical strategies among African apes, which has implications in the debate regarding the locomotor behavior from which human bipedalism arose.
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Affiliation(s)
- Julia Arias-Martorell
- Institut Català de Paleontologia Miquel Crusafont, Edifici ICTA-ICP, Carrer Columnes s/n, Campus de la UAB, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain.,Animal Postcranial Evolution (APE) Laboratory, School of Anthropology and Conservation, Marlowe Building, University of Kent, Canterbury, UK
| | - Angel Zeininger
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina, USA
| | - Tracy L Kivell
- Animal Postcranial Evolution (APE) Laboratory, School of Anthropology and Conservation, Marlowe Building, University of Kent, Canterbury, UK.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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17
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Lindshield S, Hernandez-Aguilar RA, Korstjens AH, Marchant LF, Narat V, Ndiaye PI, Ogawa H, Piel AK, Pruetz JD, Stewart FA, van Leeuwen KL, Wessling EG, Yoshikawa M. Chimpanzees (Pan troglodytes) in savanna landscapes. Evol Anthropol 2021; 30:399-420. [PMID: 34542218 DOI: 10.1002/evan.21924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 12/17/2020] [Accepted: 07/29/2021] [Indexed: 12/22/2022]
Abstract
Chimpanzees (Pan troglodytes) are the only great apes that inhabit hot, dry, and open savannas. We review the environmental pressures of savannas on chimpanzees, such as food and water scarcity, and the evidence for chimpanzees' behavioral responses to these landscapes. In our analysis, savannas were generally associated with low chimpanzee population densities and large home ranges. In addition, thermoregulatory behaviors that likely reduce hyperthermia risk, such as cave use, were frequently observed in the hottest and driest savanna landscapes. We hypothesize that such responses are evidence of a "savanna landscape effect" in chimpanzees and offer pathways for future research to understand its evolutionary processes and mechanisms. We conclude by discussing the significance of research on savanna chimpanzees to modeling the evolution of early hominin traits and informing conservation programs for these endangered apes.
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Affiliation(s)
- Stacy Lindshield
- Department of Anthropology, Purdue University, West Lafayette, Indiana, USA
| | - R Adriana Hernandez-Aguilar
- Department of Social Psychology and Quantitative Psychology, Faculty of Psychology, University of Barcelona, Barcelona, Spain.,Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Amanda H Korstjens
- Life and Environmental Sciences Department, Bournemouth University, Talbot Campus, Poole, UK
| | | | - Victor Narat
- CNRS/MNHN/Paris Diderot, UMR 7206 Eco-anthropology, Paris, France
| | - Papa Ibnou Ndiaye
- Département de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Hideshi Ogawa
- School of International Liberal Studies, Chukyo University, Toyota, Aichi, Japan
| | - Alex K Piel
- Department of Anthropology, University College London, London, UK
| | - Jill D Pruetz
- Department of Anthropology, Texas State University, San Marcos, Texas, USA
| | - Fiona A Stewart
- Department of Anthropology, University College London, London, UK.,School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK
| | - Kelly L van Leeuwen
- Department of Life and Environmental Sciences, Bournemouth University, Talbot Campus, Poole, UK
| | - Erin G Wessling
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Midori Yoshikawa
- Department of Zoology, National Museum of Nature and Science, Ibaraki, Tokyo, Japan
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18
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Raichlen DA, Pontzer H. Energetic and endurance constraints on great ape quadrupedalism and the benefits of hominin bipedalism. Evol Anthropol 2021; 30:253-261. [PMID: 34347329 DOI: 10.1002/evan.21911] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 01/13/2021] [Accepted: 05/12/2021] [Indexed: 11/10/2022]
Abstract
Bipedal walking was one of the first key behavioral traits that defined the evolution of early hominins. While it is not possible to identify specific selection pressures underlying bipedal evolution, we can better understand how the adoption of bipedalism may have benefited our hominin ancestors. Here, we focus on how bipedalism relaxes constraints on nonhuman primate quadrupedal limb mechanics, providing key advantages during hominin evolution. Nonhuman primate quadrupedal kinematics, especially in our closest living relatives, the great apes, are dominated by highly flexed limb joints, often associated with high energy costs, and are constrained by the need to reduce loads on mobile, but less stable forelimb joints. Bipedal walking would have allowed greater hind limb joint extension, which is associated with reduced energy costs and increased endurance. We suggest that relaxing these constraints provided bipedal hominins important benefits associated with long distance foraging and mobility.
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Affiliation(s)
- David A Raichlen
- Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Herman Pontzer
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina, USA.,Duke Global Health Institute, Duke University, Durham, North Carolina, USA
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19
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Bird EE, Kivell TL, Skinner MM. Cortical and trabecular bone structure of the hominoid capitate. J Anat 2021; 239:351-373. [PMID: 33942895 PMCID: PMC8273598 DOI: 10.1111/joa.13437] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 01/02/2023] Open
Abstract
Morphological variation in the hominoid capitate has been linked to differences in habitual locomotor activity due to its importance in movement and load transfer at the midcarpal joint proximally and carpometacarpal joints distally. Although the shape of bones and their articulations are linked to joint mobility, the internal structure of bones has been shown experimentally to reflect, at least in part, the loading direction and magnitude experienced by the bone. To date, it is uncertain whether locomotor differences among hominoids are reflected in the bone microarchitecture of the capitate. Here, we apply a whole‐bone methodology to quantify the cortical and trabecular architecture (separately and combined) of the capitate across bipedal (modern Homo sapiens), knuckle‐walking (Pan paniscus, Pan troglodytes, Gorilla sp.), and suspensory (Pongo sp.) hominoids (n = 69). It is hypothesized that variation in bone microarchitecture will differentiate these locomotor groups, reflecting differences in habitual postures and presumed loading force and direction. Additionally, it is hypothesized that trabecular and cortical architecture in the proximal and distal regions, as a result of being part of mechanically divergent joints proximally and distally, will differ across these portions of the capitate. Results indicate that the capitate of knuckle‐walking and suspensory hominoids is differentiated from bipedal Homo primarily by significantly thicker distal cortical bone. Knuckle‐walking taxa are further differentiated from suspensory and bipedal taxa by more isotropic trabeculae in the proximal capitate. An allometric analysis indicates that size is not a significant determinate of bone variation across hominoids, although sexual dimorphism may influence some parameters within Gorilla. Results suggest that internal trabecular and cortical bone is subjected to different forces and functional adaptation responses across the capitate (and possibly other short bones). Additionally, while separating trabecular and cortical bone is normal protocol of current whole‐bone methodologies, this study shows that when applied to carpals, removing or studying the cortical bone separately potentially obfuscates functionally relevant signals in bone structure.
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Affiliation(s)
- Emma E Bird
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Tracy L Kivell
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Matthew M Skinner
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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20
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Cazenave M, Oettlé A, Pickering TR, Heaton JL, Nakatsukasa M, Francis Thackeray J, Hoffman J, Macchiarelli R. Trabecular organization of the proximal femur in Paranthropus robustus: Implications for the assessment of its hip joint loading conditions. J Hum Evol 2021; 153:102964. [PMID: 33713985 DOI: 10.1016/j.jhevol.2021.102964] [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: 06/05/2020] [Revised: 01/28/2021] [Accepted: 01/28/2021] [Indexed: 11/19/2022]
Abstract
Reconstruction of the locomotor repertoire of the australopiths (Australopithecus and Paranthropus) has progressively integrated information from the mechanosensitive internal structure of the appendicular skeleton. Recent investigations showed that the arrangement of the trabecular network at the femoral head center is biomechanically compatible with the pattern of cortical bone distribution across the neck, both suggesting a full commitment to bipedalism in australopiths, but associated with a slightly altered gait kinematics compared to Homo involving more lateral deviation of the body center of mass over the stance limb. To provide a global picture in Paranthropus robustus of the trabecular architecture of the proximal femur across the head, neck and greater trochanter compartments, we applied techniques of virtual imaging to the variably preserved Early Pleistocene specimens SK 82, SK 97, SK 3121, SKW 19 and SWT1/LB-2 from the cave site of Swartkrans, South Africa. We also assessed the coherence between the structural signals from the center of the head and those from the trabecular network of the inferolateral portion of the head and the inferior margin of the neck, sampling the so-called vertical bundle, which in humans represents the principal compressive system of the joint. Our analyses show a functionally related trabecular organization in Pa. robustus that closely resembles the extant human condition, but which also includes some specificities in local textural arrangement. The network of the inferolateral portion of the head shows a humanlike degree of anisotropy and a bone volume fraction intermediate between the extant human and the African ape patterns. These results suggest slight differences in gait kinematics between Pa. robustus and extant humans. The neck portion of the vertical bundle revealed a less biomechanically sensitive signal. Future investigations on the australopith hip joint loading environment should more carefully investigate the trabecular structure of the trochanteric region and possible structural covariation between cortical bone distribution across the neck and site-specific trabecular properties of the arcuate bundle.
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Affiliation(s)
- Marine Cazenave
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK.
| | - Anna Oettlé
- Department of Anatomy and Histology, Sefako Makgatho Health Sciences University, Ga-Rankuwa, Pretoria, South Africa
| | - Travis Rayne Pickering
- Department of Anthropology, University of Wisconsin, Madison, USA; Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa; Plio-Pleistocene Palaeontology Section, Department of Vertebrates, Ditsong National Museum of Natural History (Transvaal Museum), Pretoria, South Africa
| | - Jason L Heaton
- Department of Biology, Birmingham-Southern College, Birmingham, USA; Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa; Plio-Pleistocene Palaeontology Section, Department of Vertebrates, Ditsong National Museum of Natural History (Transvaal Museum), Pretoria, South Africa
| | - Masato Nakatsukasa
- Laboratory of Physical Anthropology, Department of Zoology, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - J Francis Thackeray
- Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jakobus Hoffman
- South African Nuclear Energy Corporation SOC Ltd., Pelindaba, South Africa
| | - Roberto Macchiarelli
- Département Homme & Environnement, UMR 7194 CNRS, Muséum national d'Histoire naturelle, 75116, Paris, France; Unité de Formation Géosciences, Université de Poitiers, Poitiers, France
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21
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22
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Thompson NE. The biomechanics of knuckle-walking: 3-D kinematics of the chimpanzee and macaque wrist, hand and fingers. J Exp Biol 2020; 223:jeb224360. [PMID: 32554524 DOI: 10.1242/jeb.224360] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 06/05/2020] [Indexed: 08/26/2023]
Abstract
The origin and evolution of knuckle-walking has long been a key focus in understanding African ape, including human, origins. Yet, despite numerous studies documenting morphological characteristics potentially associated with knuckle-walking, little quantitative three-dimensional (3-D) data exist of forelimb motion during knuckle-walking. Nor do any comparative 3-D data exist for hand postures used during quadrupedalism in monkeys. This lack of data has limited the testability of proposed adaptations for knuckle-walking in African apes. This study presents the first 3-D kinematic data of the wrist, hand and metacarpophalangeal joints during knuckle-walking in chimpanzees and in macaques using digitigrade and palmigrade hand postures. These results clarify the unique characteristics of, and commonalities between, knuckle-walking and digitigrady/palmigrady in multiple planes of motion. Notably, chimpanzees utilized more wrist ulnar deviation than any macaque hand posture. Maximum extension of the chimpanzee wrist was slight (5-20 deg) and generally overlapped with macaque digitigrady. Metacarpophalangeal joint motion displayed distinct differences between digits in both species, likely related to the timing of force application. These data also reveal that maximum metacarpophalangeal extension angles during knuckle-walking (26-59 deg) were generally higher than previously considered. In macaques, maximum metacarpophalangeal extension during digitigrady and palmigrady overlapped for most digits, highlighting additional complexity in the interpretation of skeletal features that may be related to limiting metacarpophalangeal motion. Most importantly, however, these new 3-D data serve as a fundamental dataset with which evaluation of proposed musculoskeletal adaptations for knuckle-walking can be tested.
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Affiliation(s)
- Nathan E Thompson
- Department of Anatomy, NYIT College of Osteopathic Medicine, Old Westbury, NY 11568, USA
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23
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Morphometric analysis of the hominin talus: Evolutionary and functional implications. J Hum Evol 2020; 142:102747. [PMID: 32240884 DOI: 10.1016/j.jhevol.2020.102747] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 01/07/2020] [Accepted: 01/21/2020] [Indexed: 11/21/2022]
Abstract
The adoption of bipedalism is a key benchmark in human evolution that has impacted talar morphology. Here, we investigate talar morphological variability in extinct and extant hominins using a 3D geometric morphometric approach. The evolutionary timing and appearance of modern human-like features and their contributions to bipedal locomotion were evaluated on the talus as a whole, each articular facet separately, and multiple combinations of facets. Distinctive suites of features are consistently present in all fossil hominins, despite the presence of substantial interspecific variation, suggesting a potential connection of these suites to bipedal gait. A modern human-like condition evolved in navicular and lateral malleolar facets early in the hominin lineage compared with other facets, which demonstrate more complex morphological variation within Homininae. Interestingly, navicular facet morphology of Australopithecus afarensis is derived in the direction of Homo, whereas more recent hominin species such as Australopithecus africanus and Australopithecus sediba retain more primitive states in this facet. Combining the navicular facet with the trochlea and the posterior calcaneal facet as a functional suite, however, distinguishes Australopithecus from Homo in that the medial longitudinal arch had not fully developed in the former. Our results suggest that a more everted foot and stiffer medial midtarsal region are adaptations that coincide with the emergence of bipedalism, whereas a high medial longitudinal arch emerges later in time, within Homo. This study provides novel insights into the emergence of talar morphological traits linked to bipedalism and its transition from a facultative to an obligate condition.
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24
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Abstract
Here we present evidence of hominin locomotor behavior from the trabecular bone of the femur. We show evidence for habitual use of highly flexed hip postures, which could potentially indicate regular climbing in a South African hominin from Sterkfontein, which is either Paranthropus robustus or Homo. Second, we present evidence that Australopithecus africanus likely did not climb at the frequencies seen in extant nonhuman apes, and exhibits a modern, human-like pattern of loading at the hip joint. These results challenge the prevailing view of a single transition to bipedalism within the hominin clade by providing evidence of climbing in a more recent, non-Australopithecus South African hominin, and add to the increasing evidence for locomotor diversity in the hominin clade. Bipedalism is a defining trait of the hominin lineage, associated with a transition from a more arboreal to a more terrestrial environment. While there is debate about when modern human-like bipedalism first appeared in hominins, all known South African hominins show morphological adaptations to bipedalism, suggesting that this was their predominant mode of locomotion. Here we present evidence that hominins preserved in the Sterkfontein Caves practiced two different locomotor repertoires. The trabecular structure of a proximal femur (StW 522) attributed to Australopithecus africanus exhibits a modern human-like bipedal locomotor pattern, while that of a geologically younger specimen (StW 311) attributed to either Homo sp. or Paranthropus robustus exhibits a pattern more similar to nonhuman apes, potentially suggesting regular bouts of both climbing and terrestrial bipedalism. Our results demonstrate distinct morphological differences, linked to behavioral differences between Australopithecus and later hominins in South Africa and contribute to the increasing evidence of locomotor diversity within the hominin clade.
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25
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Ragni AJ. Trabecular architecture of the capitate and third metacarpal through ontogeny in chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla). J Hum Evol 2019; 138:102702. [PMID: 31805487 DOI: 10.1016/j.jhevol.2019.102702] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 11/18/2022]
Abstract
Chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla) both knuckle-walk in adulthood but are known to develop their locomotor strategies differently. Using dentally defined age-groups of both Pan and Gorilla and behavioral data from the literature, this study presents an internal trabecular bone approach to better understand the morphological ontogeny of knuckle-walking in these taxa. Capitate and third metacarpal bones were scanned by μCT at 23-43 μm resolution with scaled volumes of interest placed centrally within the head of the capitate and base of the third metacarpal. Trabecular measures related to activity level (size-adjusted bone volume/total volume, trabecular number, and bone surface area/bone volume) met expectations of decreasing through ontogeny in both taxa. Degree of anisotropy did not show statistical support for predicted species differences, but this may be due to the sample size as observed changes through ontogeny reflect expected trends in the capitate. Analyses of principal trabecular orientation corroborated known behavioral differences related to variation of hand use in these taxa, but only Pan showed directional patterning associated with suggested wrist posture. Assessment of allometry showed that the trabecular bone of larger animals is characterized by fewer and thinner trabeculae relative to bone size. In combination, these findings confirm the efficacy of trabecular bone in reflecting locomotor ontogeny differences between closely related taxa. These techniques show promise for use within the hominin fossil record, particularly for taxa hypothesized to be arboreal in some capacity.
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Affiliation(s)
- Anna J Ragni
- Richard Gilder Graduate School, American Museum of Natural History, New York, NY, USA; New York Consortium in Evolutionary Primatology, New York, NY, USA; Department of Anthropology, Smithsonian Institution, National Museum of Natural History, Washington, DC, USA.
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26
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Georgiou L, Kivell TL, Pahr DH, Buck LT, Skinner MM. Trabecular architecture of the great ape and human femoral head. J Anat 2019; 234:679-693. [PMID: 30793309 PMCID: PMC6481414 DOI: 10.1111/joa.12957] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2019] [Indexed: 11/27/2022] Open
Abstract
Studies of femoral trabecular structure have shown that the orientation and volume of bone are associated with variation in loading and could be informative about individual joint positioning during locomotion. In this study, we analyse for the first time trabecular bone patterns throughout the femoral head using a whole-epiphysis approach to investigate how potential trabecular variation in humans and great apes relates to differences in locomotor modes. Trabecular architecture was analysed using microCT scans of Pan troglodytes (n = 20), Gorilla gorilla (n = 14), Pongo sp. (n = 5) and Homo sapiens (n = 12) in medtool 4.1. Our results revealed differences in bone volume fraction (BV/TV) distribution patterns, as well as overall trabecular parameters of the femoral head between great apes and humans. Pan and Gorilla showed two regions of high BV/TV in the femoral head, consistent with hip posture and loading during two discrete locomotor modes: knuckle-walking and climbing. Most Pongo specimens also displayed two regions of high BV/TV, but these regions were less discrete and there was more variability across the sample. In contrast, Homo showed only one main region of high BV/TV in the femoral head and had the lowest BV/TV, as well as the most anisotropic trabeculae. The Homo trabecular structure is consistent with stereotypical loading with a more extended hip compared with great apes, which is characteristic of modern human bipedalism. Our results suggest that holistic evaluations of femoral head trabecular architecture can reveal previously undetected patterns linked to locomotor behaviour in extant apes and can provide further insight into hip joint loading in fossil hominins and other primates.
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Affiliation(s)
- Leoni Georgiou
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
| | - Tracy L. Kivell
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
| | - Dieter H. Pahr
- Institute for Lightweight Design and Structural BiomechanicsVienna University of TechnologyViennaAustria
- Department of Anatomy and BiomechanicsKarl Landsteiner Private University of Health SciencesKrems an der DonauAustria
| | - Laura T. Buck
- Department of AnthropologyUniversity of CaliforniaDavisCAUSA
| | - Matthew M. Skinner
- Skeletal Biology Research CentreSchool of Anthropology and ConservationUniversity of KentCanterburyUK
- Department of Human EvolutionMax Planck Institute for Evolutionary AnthropologyLeipzigGermany
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27
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Martin MA. Biological Anthropology in 2018: Grounded in Theory, Questioning Contexts, Embracing Innovation. AMERICAN ANTHROPOLOGIST 2019. [DOI: 10.1111/aman.13233] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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28
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Druelle F, Berthet M, Quintard B. The body center of mass in primates: Is it more caudal than in other quadrupedal mammals? AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:170-178. [DOI: 10.1002/ajpa.23813] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 02/10/2019] [Accepted: 02/19/2019] [Indexed: 12/16/2022]
Affiliation(s)
- François Druelle
- Laboratory for Functional Morphology, Biology DepartmentUniversity of Antwerp Campus Drie Eiken (Building D) Antwerp Belgium
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29
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Druelle F, Schoonaert K, Aerts P, Nauwelaerts S, Stevens JMG, D'Août K. Segmental morphometrics of bonobos (Pan paniscus): are they really different from chimpanzees (Pan troglodytes)? J Anat 2018; 233:843-853. [PMID: 30294787 PMCID: PMC6231171 DOI: 10.1111/joa.12894] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2018] [Indexed: 11/28/2022] Open
Abstract
The inertial properties of body segments reflect performance and locomotor habits in primates. While Pan paniscus is generally described as more gracile, lighter in body mass, and as having relatively longer and heavier hindlimbs than Pan troglodytes, both species exhibit very similar patterns of (quadrupedal and bipedal) kinematics, but show slightly different locomotor repertoires. We used a geometric model to estimate the inertial properties for all body segments (i.e. head, trunk, upper and lower arms, hand, thigh, shank and foot) using external length and diameter measurements of 12 anaesthetized bonobos (eight adults and four immatures). We also calculated whole limb inertial properties. When we compared absolute and relative segment morphometric and inertial variables between bonobos and chimpanzees, we found that adult bonobos are significantly lighter than adult chimpanzees. The bonobo is also shorter in head length, upper and lower arm lengths, and foot length, and is generally lighter in most absolute segment mass values (except head and hand). In contrast, the bonobo has a longer trunk. When scaled relative to body mass, most differences disappear between the two species. Only the longer trunk and the shorter head of the bonobo remain apparent, as well as the lighter thigh compared with the chimpanzee. We found similar values of natural pendular periods of the limbs in both species, despite differences in absolute limb lengths, masses, mass centres (for the hindlimb) and moments of inertia. While our data contradict the commonly accepted view that bonobos have relatively longer and heavier hindlimbs than chimpanzees, they are consistent with the observed similarities in the quadrupedal and bipedal kinematics between these species. The morphological differences between both species are more subtle than those previously described from postcranial osteological materials.
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Affiliation(s)
- François Druelle
- Laboratory for Functional MorphologyUniversity of AntwerpWilrijkBelgium
| | - Kirsten Schoonaert
- Laboratory for Functional MorphologyUniversity of AntwerpWilrijkBelgium
- Antwerp Zoo Centre for Research and ConservationAntwerpBelgium
| | - Peter Aerts
- Laboratory for Functional MorphologyUniversity of AntwerpWilrijkBelgium
- Department of Movement and Sports SciencesUniversity of GhentGentBelgium
| | - Sandra Nauwelaerts
- Laboratory for Functional MorphologyUniversity of AntwerpWilrijkBelgium
- Antwerp Zoo Centre for Research and ConservationAntwerpBelgium
| | - Jeroen M. G. Stevens
- Antwerp Zoo Centre for Research and ConservationAntwerpBelgium
- Institute of Ageing and Chronic DiseaseUniversity of LiverpoolLiverpoolUK
| | - Kristiaan D'Août
- Behavioural Ecology and Ecophysiology GroupUniversity of AntwerpWilrijkBelgium
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Thompson NE, Rubinstein D, Larson SG. Great ape thorax and shoulder configuration-An adaptation for arboreality or knuckle-walking? J Hum Evol 2018; 125:15-26. [PMID: 30502892 DOI: 10.1016/j.jhevol.2018.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 09/19/2018] [Accepted: 09/24/2018] [Indexed: 10/28/2022]
Abstract
Great apes exhibit a suite of morphological traits of the shoulder and upper thorax that have traditionally been linked to orthograde arborealism. Recently it has been proposed that these traits are instead adaptations for knuckle-walking, and more broadly, that knuckle-walking itself is an adaptation for shock absorption during terrestriality. Here we test several tenets of these hypotheses using kinematic and kinetic data from chimpanzees and macaques, and electromyographic data of shoulder muscle activity in chimpanzees. We collected 3D kinematic data to quantify motion of the acromion and trunk during quadrupedalism and vertical climbing in chimpanzees as well as ground reaction forces to investigate the presence and magnitude of impact transient forces during terrestrial locomotion in chimpanzees and macaques. We also investigated patterns of recruitment of select forelimb musculature (triceps brachii and serratus anterior) using previously collected data in chimpanzees to determine whether these muscles may function to absorb impact transient forces. We found that the acromion is significantly more elevated in vertical climbing than during knuckle-walking, while dorsoventral ranges and magnitudes of motion were similar between gaits. Ground reaction forces indicate that only a minority of strides in either chimpanzees or macaques have transient forces and, when present, these transient forces as well as loading rates are small. Electromyographic results show that activity of the triceps brachii may facilitate energy absorption while serratus anterior likely functions to support the trunk, as in other primates. Our data suggest there is little to no evidence supporting recent hypotheses that the African ape upper thorax and shoulder configuration is an adaptation for knuckle-walking, or more broadly, that knuckle-walking exists as an adaptation to absorb impact shock during terrestriality. We do however find some evidence that shoulder configuration allows greater scapular elevation in chimpanzees during arboreal behaviors (e.g., vertical climbing).
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Affiliation(s)
- Nathan E Thompson
- Department of Anatomy, NYIT College of Osteopathic Medicine, Old Westbury, NY 11568, USA.
| | - Danielle Rubinstein
- New York Institute of Technology, College of Osteopathic Medicine, NY 11568 USA
| | - Susan G Larson
- Department of Anatomical Sciences, Stony Brook University School of Medicine, Stony Brook, NY 11794-8081, USA
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Ryan TM, Carlson KJ, Gordon AD, Jablonski N, Shaw CN, Stock JT. Human-like hip joint loading in Australopithecus africanus and Paranthropus robustus. J Hum Evol 2018; 121:12-24. [DOI: 10.1016/j.jhevol.2018.03.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 03/22/2018] [Accepted: 03/23/2018] [Indexed: 02/02/2023]
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Georgiou L, Kivell TL, Pahr DH, Skinner MM. Trabecular bone patterning in the hominoid distal femur. PeerJ 2018; 6:e5156. [PMID: 30002981 PMCID: PMC6035864 DOI: 10.7717/peerj.5156] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 06/13/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND In addition to external bone shape and cortical bone thickness and distribution, the distribution and orientation of internal trabecular bone across individuals and species has yielded important functional information on how bone adapts in response to load. In particular, trabecular bone analysis has played a key role in studies of human and nonhuman primate locomotion and has shown that species with different locomotor repertoires display distinct trabecular architecture in various regions of the skeleton. In this study, we analyse trabecular structure throughout the distal femur of extant hominoids and test for differences due to locomotor loading regime. METHODS Micro-computed tomography scans of Homo sapiens (n = 11), Pan troglodytes (n = 18), Gorilla gorilla (n = 14) and Pongo sp. (n = 7) were used to investigate trabecular structure throughout the distal epiphysis of the femur. We predicted that bone volume fraction (BV/TV) in the medial and lateral condyles in Homo would be distally concentrated and more anisotropic due to a habitual extended knee posture at the point of peak ground reaction force during bipedal locomotion, whereas great apes would show more posteriorly concentrated BV/TV and greater isotropy due to a flexed knee posture and more variable hindlimb use during locomotion. RESULTS Results indicate some significant differences between taxa, with the most prominent being higher BV/TV in the posterosuperior region of the condyles in Pan and higher BV/TV and anisotropy in the posteroinferior region in Homo. Furthermore, trabecular number, spacing and thickness differ significantly, mainly separating Gorilla from the other apes. DISCUSSION The trabecular architecture of the distal femur holds a functional signal linked to habitual behaviour; however, there was more similarity across taxa and greater intraspecific variability than expected. Specifically, there was a large degree of overlap in trabecular structure across the sample, and Homo was not as distinct as predicted. Nonetheless, this study offers a comparative sample of trabecular structure in the hominoid distal femur and can contribute to future studies of locomotion in extinct taxa.
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Affiliation(s)
- Leoni Georgiou
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent at Canterbury, Canterbury, Kent, UK
| | - Tracy L. Kivell
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent at Canterbury, Canterbury, Kent, UK
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Dieter H. Pahr
- Institute for Lightweight Design and Structural Biomechanics, Vienna University of Technology, Vienna, Austria
- Department of Anatomy and Biomechanics, Karl Landsteiner Private University of Health Sciences, Krems an der Donau, Austria
| | - Matthew M. Skinner
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent at Canterbury, Canterbury, Kent, UK
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Sellers WI, Hirasaki E. Quadrupedal locomotor simulation: producing more realistic gaits using dual-objective optimization. ROYAL SOCIETY OPEN SCIENCE 2018; 5:171836. [PMID: 29657790 PMCID: PMC5882714 DOI: 10.1098/rsos.171836] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 02/01/2018] [Indexed: 06/08/2023]
Abstract
In evolutionary biomechanics it is often considered that gaits should evolve to minimize the energetic cost of travelling a given distance. In gait simulation this goal often leads to convincing gait generation. However, as the musculoskeletal models used get increasingly sophisticated, it becomes apparent that such a single goal can lead to extremely unrealistic gait patterns. In this paper, we explore the effects of requiring adequate lateral stability and show how this increases both energetic cost and the realism of the generated walking gait in a high biofidelity chimpanzee musculoskeletal model. We also explore the effects of changing the footfall sequences in the simulation so it mimics both the diagonal sequence walking gaits that primates typically use and also the lateral sequence walking gaits that are much more widespread among mammals. It is apparent that adding a lateral stability criterion has an important effect on the footfall phase relationship, suggesting that lateral stability may be one of the key drivers behind the observed footfall sequences in quadrupedal gaits. The observation that single optimization goals are no longer adequate for generating gait in current models has important implications for the use of biomimetic virtual robots to predict the locomotor patterns in fossil animals.
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Affiliation(s)
- William Irvin Sellers
- School of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
| | - Eishi Hirasaki
- Primate Research Institute, Kyoto University, Inuyama, Japan
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Samuel DS, Nauwelaerts S, Stevens JMG, Kivell TL. Hand pressures during arboreal locomotion in captive bonobos (Pan paniscus). J Exp Biol 2018. [DOI: 10.1242/jeb.170910] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Evolution of the human hand has undergone a transition from use during locomotion to use primarily for manipulation. Previous comparative morphological and biomechanical studies have focused on potential changes in manipulative abilities during human hand evolution, but few have focused on functional signals for arboreal locomotion. Here, we provide this comparative context though the first analysis of hand loading in captive bonobos during arboreal locomotion. We quantify pressure experienced by the fingers, palm and thumb in bonobos during vertical locomotion, suspension and arboreal knuckle-walking. Results show that pressure experienced by the fingers is significantly higher during knuckle-walking compared with similar pressures experienced by the fingers and palm during suspensory and vertical locomotion. Peak pressure is most often experienced at or around the third digit in all locomotor modes. Pressure quantified for the thumb is either very low or absent, despite the thumb making contact with the substrate during all suspensory and vertical locomotor trials. Unlike chimpanzees, the bonobos do not show a rolling pattern of digit contact with the substrate during arboreal knuckle-walking but, instead, digits 3 and 4 typically touch down first and digit 5 almost always made contact with the substrate. These results have implications for interpreting extant and fossilised hand morphology; we expect bonobo (and chimpanzee) bony morphology to primarily reflect the biomechanical loading of knuckle-walking, while functional signals for arboreal locomotion in fossil hominins are most likely to appear in the fingers, particularly digit 3, and least likely to appear in the morphology of the thumb.
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Affiliation(s)
- Diana S. Samuel
- Animal Postcranial Evolution (APE) Lab, Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
| | - Sandra Nauwelaerts
- Laboratory for Functional morphology, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
- Centre for Research and Conservation (CRC), Koningin Astridplein 20-26, 2018 Antwerp, Belgium
| | - Jeroen M. G. Stevens
- Centre for Research and Conservation (CRC), Koningin Astridplein 20-26, 2018 Antwerp, Belgium
- Behavioral Ecology and Ecophysiology group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Tracy L. Kivell
- Animal Postcranial Evolution (APE) Lab, Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany
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