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Orr CM, Atkinson R, Ernewein J, Tocheri MW. Carpal kinematics and morphological correlates of wrist ulnar deviation mobility in nonhuman anthropoid primates. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024; 183:e24728. [PMID: 36924247 DOI: 10.1002/ajpa.24728] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 02/09/2023] [Accepted: 03/05/2023] [Indexed: 03/18/2023]
Abstract
OBJECTIVES Primates employ wrist ulnar deviation during a variety of locomotor and manipulative behaviors. Extant hominoids share a derived condition in which the ulnar styloid process has limited articulation or is completely separated from the proximal carpals, which is often hypothesized to increase ulnar deviation range of motion. Acute angulation of the hamate's triquetral facet is also hypothesized to facilitate ulnar deviation mobility and mechanics. In this study, we test these longstanding ideas. METHODS Three-dimensional (3D) carpal kinematics were examined using a cadaveric sample of Pan troglodytes, Pongo sp., and five monkey species. Ulnar styloid projection and orientation of the hamate's triquetral facet were quantified using 3D models. RESULTS Although carpal rotation patterns in Pan and Pongo were uniquely similar in some respects, P. troglodytes exhibited overall kinematic similarity with large terrestrial cercopithecoids (Papio and Mandrillus). Pongo, Macaca, and Ateles had high wrist ulnar deviation ranges of motion, but Pongo did this via a unique mechanism. In Pongo, the triquetrum functions as a distal carpal rather than part of the proximal row. Ulnar styloid projection and wrist ulnar deviation range of motion were not correlated but ulnar deviation range of motion and the triquetrohamate facet orientation were correlated. CONCLUSIONS Increased ulnar deviation mobility is not the function of ulnar styloid withdrawal in hominoids. Instead, this feature probably reduces stress on the ulnar side wrist or is a byproduct of adaptations that increase supination. Orientation of the hamate's triquetral facet offers some potential to reconstruct ulnar deviation mobility in extinct primates.
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Affiliation(s)
- Caley M Orr
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Anthropology, University of Colorado Denver, Denver, Colorado, USA
| | - Richard Atkinson
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, Illinois, USA
| | - Jamie Ernewein
- Modern Human Anatomy Program, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- University of Colorado School of Medicine, Colorado State University, Fort Collins, Colorado, USA
- College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Matthew W Tocheri
- Department of Anthropology, Lakehead University, Thunder Bay, Ontario, Canada
- Human Origins Program, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
- Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, University of Wollongong, Wollongong, Australia
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2
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Law CJ, Hlusko LJ, Tseng ZJ. Uncovering the mosaic evolution of the carnivoran skeletal system. Biol Lett 2024; 20:20230526. [PMID: 38263882 PMCID: PMC10806395 DOI: 10.1098/rsbl.2023.0526] [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: 11/09/2023] [Accepted: 12/21/2023] [Indexed: 01/25/2024] Open
Abstract
The diversity of vertebrate skeletons is often attributed to adaptations to distinct ecological factors such as diet, locomotion, and sensory environment. Although the adaptive evolution of skull, appendicular skeleton, and vertebral column is well studied in vertebrates, comprehensive investigations of all skeletal components simultaneously are rarely performed. Consequently, we know little of how modes of evolution differ among skeletal components. Here, we tested if ecological and phylogenetic effects led to distinct modes of evolution among the cranial, appendicular and vertebral regions in extant carnivoran skeletons. Using multivariate evolutionary models, we found mosaic evolution in which only the mandible, hindlimb and posterior (i.e. last thoracic and lumbar) vertebrae showed evidence of adaptation towards ecological regimes whereas the remaining skeletal components reflect clade-specific evolutionary shifts. We hypothesize that the decoupled evolution of individual skeletal components may have led to the origination of distinct adaptive zones and morphologies among extant carnivoran families that reflect phylogenetic hierarchies. Overall, our work highlights the importance of examining multiple skeletal components simultaneously in ecomorphological analyses. Ongoing work integrating the fossil and palaeoenvironmental record will further clarify deep-time drivers that govern the carnivoran diversity we see today and reveal the complexity of evolutionary processes in multicomponent systems.
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Affiliation(s)
- Chris J. Law
- Department of Integrative Biology, University of Texas, Austin, TX, USA
- Burke Museum and Department of Biology, University of Washington, Seattle, WA, USA
- Department of Integrative Biology, University of California, Berkeley, CA, USA
| | - Leslea J. Hlusko
- National Research Center on Human Evolution (CENIEH), Burgos, Spain
| | - Z. Jack Tseng
- Department of Integrative Biology, University of California, Berkeley, CA, USA
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Frost SR, Jablonski NG, Haile-Selassie Y. The earliest most complete skeleton of Theropithecus. J Hum Evol 2023; 180:103370. [PMID: 37167814 DOI: 10.1016/j.jhevol.2023.103370] [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: 08/05/2022] [Revised: 03/30/2023] [Accepted: 03/30/2023] [Indexed: 05/13/2023]
Abstract
The middle Pliocene site of Woranso-Mille in the Afar Region of Ethiopia has yielded numerous significant early hominin fossils representing multiple, coexisting taxa. Here we report on another significant discovery, the oldest partial skeleton of the papionin, Theropithecus. The specimen was recovered from the Aralee Issie collection area over multiple field seasons from 2004 through 2019. The specimen was unearthed in situ from the fluvial facies of the Mesgid Dora Tuff dated to 3.66-3.57 Ma. The partial skeleton, ARI-VP-1/26, is that of a subadult male lacking a skull. In the absence of unambiguously associated craniodental remains, the male status of the specimen was established from the dimensions of the long bones in comparison to those of other Theropithecus from Woranso-Mille. ARI-VP-1/26 is noteworthy because it preserves partial hand and foot skeletons, including a complete set of metacarpals from the left side. The theropith status of ARI-VP-1/26 was established based on the detailed anatomy of the postcranial skeleton, especially the proximal and distal humerus, proximal radius, and proximal femur. The morphology of the postcranium of ARI-VP-1/26 is consistent with that of recognized Theropithecus from Woranso-Mille and, specifically, with specimens recognized as Theropithecus oswaldi cf. darti from other sites. The ratio of the lengths of the first metacarpal to metacarpals 2-5 in ARI-VP-1/26 is intermediate between that seen in extant Papio and Theropithecus. In Theropithecus gelada and Theropithecus brumpti, the pairing of pollical and indical metacarpals of near equal length contributes to the species' high opposability index and is associated with a 'manual grazing' feeding habit. Cercopithecids constitute 43% of the identified vertebrates at Aralee Issie, and T. oswaldi cf. darti is the most common mammalian species. The monkeys of Aralee Issie lived in an open shrubland habitat, but the specific reasons for their high prevalence at the site are unclear.
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Affiliation(s)
- Stephen R Frost
- Department of Anthropology, University of Oregon, Eugene, OR 97403-1218, USA.
| | - Nina G Jablonski
- Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA
| | - Yohannes Haile-Selassie
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85281, USA
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4
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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: 4] [Impact Index Per Article: 4.0] [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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Wennemann SE, Lewton KL, Orr CM, Almécija S, Tocheri MW, Jungers WL, Patel BA. A geometric morphometric approach to investigate primate proximal phalanx diaphysis shape. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2022; 177:581-602. [PMID: 35755956 PMCID: PMC9231826 DOI: 10.1002/ajpa.24460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Current approaches to quantify phalangeal curvature assume that the long axis of the bone's diaphysis approximates the shape of a portion of a circle (included angle method) or a parabola (second-degree polynomial method). Here we developed, tested, and employed an alternative geometric morphometrics-based approach to quantify diaphysis shape of proximal phalanges in humans, apes and monkeys with diverse locomotor behaviors. 100 landmarks of the central longitudinal axis were extracted from 3D surface models and analyzed using 2DGM methods, including Generalized Procrustes Analyses. Principal components analyses were performed and PC1 scores (>80% of variation) represented the dorsopalmar shape of the bone's central longitudinal axis and separated taxa consistently and in accord with known locomotor behavioral profiles. The most suspensory taxa, including orangutans, hylobatids and spider monkeys, had significantly lower PC1 scores reflecting the greatest amounts of phalangeal curvature. In contrast, bipedal humans and the quadrupedal cercopithecoid monkeys sampled (baboons, proboscis monkeys) exhibited significantly higher PC1 scores reflecting flatter phalanges. African ape (gorillas, chimpanzees and bonobos) phalanges fell between these two extremes and were not significantly different from each other. PC1 scores were significantly correlated with both included angle and the a coefficient of a second-degree polynomial calculated from the same landmark dataset, but had a significantly higher correlation with included angles. Our alternative approach for quantifying diaphysis shape of proximal phalanges to investigate dorsopalmar curvature is replicable and does not assume a priori either a circle or parabola model of shape, making it an attractive alternative compared with existing methodologies.
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Affiliation(s)
- Sophie E. Wennemann
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Kristi L. Lewton
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA,Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Caley M. Orr
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045, USA,Department of Anthropology, University of Colorado Denver, Denver, CO 80217, USA
| | - Sergio Almécija
- Division of Anthropology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA,New York Consortium in Evolutionary Primatology, New York, NY, USA,Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, c/ Columnes s/n, Campus de la UAB, 08193, Cerdanyola del Vallès, Barcelona, Spain
| | - Matthew W. Tocheri
- Department of Anthropology, Lakehead University, Thunder Bay, Ontario P7B 5E1, Canada,Human Origins Program, National Museum of Natural History, Smithsonian Institution, Washington DC 20013, USA,Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, University of Wollongong, Wollongong, New South Wales, 2522, Australia
| | - William L. Jungers
- Department of Anatomical Sciences, Stony Brook University School of Medicine, Stony Brook, NY 11794, USA,Association Vahatra, BP 3972, Antananarivo 101, Madagascar
| | - Biren A. Patel
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA,Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA,Corresponding author: Biren A. Patel, 1333 San Pablo Street, BMT 404, Keck School of Medicine, University of Southern California, Los Angeles CA, 90033, USA;
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6
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Anderson M. An assessment of the postcranial skeleton of the Paracolobus mutiwa (Primates: Colobinae) specimen KNM-WT 16827 from Lomekwi, West Turkana, Kenya. J Hum Evol 2021; 156:103012. [PMID: 34004496 DOI: 10.1016/j.jhevol.2021.103012] [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: 03/09/2019] [Revised: 04/09/2021] [Accepted: 04/10/2021] [Indexed: 11/17/2022]
Abstract
The postcranium of a large-bodied colobine monkey attributed to Paracolobus mutiwa from the site of Lomekwi, West Turkana, Kenya, is described. The partial skeleton (KNM-WT 16827) was recovered from locality LO 1, dated to 2.58-2.53 Ma, and preserves postcranial elements including fragments of scapula, humerus, proximal ulna, proximal radius, os coxae, proximal femur, astragalus, and calcaneus. KNM-WT 16827 was identified as P. mutiwa based on cranial similarities to the holotype female maxilla (KNM-ER 3843) and the holotype of Paracolobus chemeroni (KNM-BC 3), but is currently the only specimen of this taxon with associated cranial and postcranial elements. The skeleton is morphologically distinct from other large cercopithecid specimens from the Turkana Basin, including several assigned to Cercopithecoides williamsi, Cercopithecoides kimeui, Rhinocolobus turkanaensis, and Theropithecus oswaldi and differs from KNM-BC 3 in the larger cranium and shorter and more robust long bones. KNM-WT 16827 has forelimb and hindlimb features exhibiting a mixture of traits more associated with terrestrial locomotor behavior, including robust humeral deltoid tuberosity, retroflexed humeral medial epicondyle, deep ulnar trochlear notch, relatively short lower iliac height, prominent femoral greater trochanter, asymmetrical astragalar trochlea, and weak digit flexor grooves on the calcaneus. KNM-WT 16827 is also proportionally distinct from KNM-BC 3 and other Turkana Basin specimens attributed to large-bodied taxa such as C. williamsi, C. kimeui, R. turkanaensis, and T. oswaldi in having relatively shorter limbs and smaller tarsals. The traits shared with P. chemeroni and other extinct taxa are either typical for colobines, or likely due to P. mutiwa and P. chemeroni sharing adaptations for terrestrial locomotion relative to extant colobinans. Although a full cranial assessment is needed, based on its postcranial morphology KNM-WT 16827 is distinct from KNM-BC 3, C. williamsi, R. turkanaensis, Theropithecus, and extant colobines, warranting further analyses to better assess the taxonomic assignment of the specimen.
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Affiliation(s)
- Monya Anderson
- Department of Anthropology, Texas A&M University, Anthropology 225, TAMU 4352, College Station, TX, 77843, USA.
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7
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Prang TC, Ramirez K, Grabowski M, Williams SA. Ardipithecus hand provides evidence that humans and chimpanzees evolved from an ancestor with suspensory adaptations. SCIENCE ADVANCES 2021; 7:eabf2474. [PMID: 33627435 PMCID: PMC7904256 DOI: 10.1126/sciadv.abf2474] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/12/2021] [Indexed: 05/08/2023]
Abstract
The morphology and positional behavior of the last common ancestor of humans and chimpanzees are critical for understanding the evolution of bipedalism. Early 20th century anatomical research supported the view that humans evolved from a suspensory ancestor bearing some resemblance to apes. However, the hand of the 4.4-million-year-old hominin Ardipithecus ramidus purportedly provides evidence that the hominin hand was derived from a more generalized form. Here, we use morphometric and phylogenetic comparative methods to show that Ardipithecus retains suspensory adapted hand morphologies shared with chimpanzees and bonobos. We identify an evolutionary shift in hand morphology between Ardipithecus and Australopithecus that renews questions about the coevolution of hominin manipulative capabilities and obligate bipedalism initially proposed by Darwin. Overall, our results suggest that early hominins evolved from an ancestor with a varied positional repertoire including suspension and vertical climbing, directly affecting the viable range of hypotheses for the origin of our lineage.
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Affiliation(s)
- Thomas C Prang
- Department of Anthropology, Texas A&M University, College Station, TX 77843, USA.
| | - Kristen Ramirez
- New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
- Department of Anthropology, CUNY Graduate Center, New York, NY 10016, USA
- Office of Medical Education, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Mark Grabowski
- Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University, Liverpool, UK
- Centre for Ecology and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Scott A Williams
- New York Consortium in Evolutionary Primatology, New York, NY 10024, USA
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY 10003, USA
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg, South Africa
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8
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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: 9] [Impact Index Per Article: 2.3] [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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Correlation between musculoskeletal structure of the hand and primate locomotion: Morphometric and mechanical analysis in prehension using the cross- and triple-ratios. PLoS One 2020; 15:e0232397. [PMID: 32365096 PMCID: PMC7197777 DOI: 10.1371/journal.pone.0232397] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 04/14/2020] [Indexed: 11/22/2022] Open
Abstract
Biometric ratios of the relative length of the rays in the hand have been analyzed between primate species in the light of their hand function or phylogeny. However, how relative lengths among phalanges are mechanically linked to the grasping function of primates with different locomotor behaviors remains unclear. To clarify this, we calculated cross and triple-ratios, which are related to the torque distribution, and the torque generation mode at different joint angles using the lengths of the phalanges and metacarpal bones in 52 primates belonging to 25 species. The torque exerted on the finger joint and traction force of the flexor tendons necessary for a cylindrical grip and a suspensory hand posture were calculated using the moment arm of flexor tendons measured on magnetic resonance images, and were compared among Hylobates spp., Ateles sp., and Papio hamadryas. Finally, the torques calculated from the model were validated by a mechanical study detecting the force exerted on the phalanx by pulling the digital flexor muscles during suspension in these three species. Canonical discriminant analysis of cross and triple-ratios classified primates almost in accordance with their current classification based on locomotor behavior. The traction force was markedly reduced with flexion of the MCP joint parallel to the torque in brachiating primates; this was notably lower in the terrestrial quadrupedal primates than in the arboreal primates at mild flexion. Our mechanical study supported these features in the torque and traction force generation efficiencies. Our results suggest that suspensory or terrestrial quadrupedal primates have hand structures that can exert more torque at a suspensory posture, or palmigrade and digitigrade locomotion, respectively. Furthermore, our study suggests availability of the cross and triple-ratios as one of the indicators to estimate the hand function from the skeletal structure.
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10
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Not all fine-branch locomotion is equal: Grasping morphology determines locomotor performance on narrow supports. J Hum Evol 2020; 142:102767. [DOI: 10.1016/j.jhevol.2020.102767] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 02/19/2020] [Accepted: 02/19/2020] [Indexed: 02/05/2023]
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Ríos‐Orjuela JC, Camacho‐Bastidas JS, Jerez A. Appendicular morphology and locomotor performance of two morphotypes of continental anoles: Anolis heterodermus and Anolis tolimensis. J Anat 2020; 236:252-273. [PMID: 31724173 PMCID: PMC6956434 DOI: 10.1111/joa.13092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2019] [Indexed: 11/30/2022] Open
Abstract
Anolis lizards have been a model of study in ecomorphology in the Caribbean islands because species with the same type of microhabitat share similar morphological features. But despite their great diversity, little is known about continental species. We analyzed the relationship between the anatomical characteristics of the appendicular skeleton and the locomotor performance of two Anolis species found in Colombia that have different use of habitat. Anolis heterodermus, a strictly arboreal species, was compared with Anolis tolimensis, which inhabits the lower strata of vegetation. These two species differ in their body plan not only in body shape and external morphological features, but also in the skeleton and appendicular musculature. The results highlight the muscle and bone specializations associated with the use of habitat in this genus, such as the presence of more robust bones to enlarge the surface of muscle insertion, the thickening and loss of carpal parts, thickening of tendons associated with the manus, and greater development of muscle mass in the forelimbs by A. heterodermus with respect to A. tolimensis. These differences are related to the use of the microhabitat and the locomotor style of each species.
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Affiliation(s)
- Juan Camilo Ríos‐Orjuela
- Laboratorio de Ecología EvolutivaDepartamento de BiologíaFacultad de CienciasUniversidad Nacional de ColombiaBogotáColombia
- Museu de Zoologia da Universidade de São PauloSão PauloBrazil
| | | | - Adriana Jerez
- Laboratorio de Ecología EvolutivaDepartamento de BiologíaFacultad de CienciasUniversidad Nacional de ColombiaBogotáColombia
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Orr CM. Kinematics of the anthropoid os centrale and the functional consequences of scaphoid-centrale fusion in African apes and hominins. J Hum Evol 2017; 114:102-117. [PMID: 29447753 DOI: 10.1016/j.jhevol.2017.10.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 09/21/2017] [Accepted: 10/05/2017] [Indexed: 02/07/2023]
Abstract
In most primates, the os centrale is interposed between the scaphoid, trapezoid, trapezium, and head of the capitate, thus constituting a component of the wrist's midcarpal complex. Scaphoid-centrale fusion is among the clearest morphological synapomorphies of African apes and hominins. Although it might facilitate knuckle-walking by increasing the rigidity and stability of the radial side of the wrist, the exact functional significance of scaphoid-centrale fusion is unclear. If fusion acts to produce a more rigid radial wrist that stabilizes the hand and limits shearing stresses, then in taxa with a free centrale, it should anchor ligaments that check extension and radial deviation, but exhibit motion independent of the scaphoid. Moreover, because the centrale sits between the scaphoid and capitate (a major stabilizing articulation), scaphoid-centrale mobility should correlate with scaphocapitate mobility in extension and radial deviation. To test these hypotheses, the centrale's ligamentous binding was investigated via dissection in Pongo and Papio, and the kinematics of the centrale were quantified in a cadaveric sample of anthropoids (Pongo sp., Ateles geoffroyi, Colobus guereza, Macaca mulatta, and Papio anubis) using a computed-tomography-based method to track wrist-bone motion. Results indicate that the centrale rotates freely relative to the scaphoid in all taxa. However, centrale mobility is only correlated with scaphocapitate mobility during extension in Pongo-possibly due to differences in overall wrist configuration between apes and monkeys. If an extant ape-like wrist characterized early ancestors of African apes and hominins, then scaphoid-centrale fusion would have increased midcarpal rigidity in extension relative to the primitive condition. Although biomechanically consistent with a knuckle-walking hominin ancestor, this assumes that the trait evolved specifically for that biological role, which must be squared with contradictory interpretations of extant and fossil hominoid morphology. Regardless of its original adaptive significance, scaphoid-centrale fusion likely presented a constraint on early hominin midcarpal mobility.
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Affiliation(s)
- Caley M Orr
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA; Department of Anthropology, University of Colorado Denver, Denver, CO, USA.
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Druelle F, Young J, Berillon G. Behavioral implications of ontogenetic changes in intrinsic hand and foot proportions in olive baboons (Papio Anubis). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 165:65-76. [DOI: 10.1002/ajpa.23331] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/15/2017] [Accepted: 09/18/2017] [Indexed: 01/30/2023]
Affiliation(s)
- François Druelle
- Laboratory for Functional Morphology, Department of Biology; University of Antwerp, Universiteitsplein 1; Antwerpen, B-2610 Belgium
- Primatology Station of the CNRS, UPS 846, RD 56; Rousset-sur-Arc, 13790 France
| | - Jesse Young
- Department of Anatomy and Neurobiology; Northeast Ohio Medical University, NEOMED 4209 State Route 44; Rootstown Ohio 44272
| | - Gilles Berillon
- Primatology Station of the CNRS, UPS 846, RD 56; Rousset-sur-Arc, 13790 France
- Département de Préhistoire; Musée de L'Homme, UMR 7194 CNRS-MNHN, Place du Trocadéro; Paris, 75116 France
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14
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Intra-individual variation in hand postures during terrestrial locomotion in Japanese macaques (Macaca fuscata). Primates 2017; 59:61-68. [DOI: 10.1007/s10329-017-0619-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 07/08/2017] [Indexed: 10/19/2022]
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15
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Zeininger A, Shapiro LJ, Raichlen DA. Ontogenetic changes in limb postures and their impact on effective limb length in baboons (P
apio cynocephalus
). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 163:231-241. [DOI: 10.1002/ajpa.23201] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/08/2017] [Accepted: 02/20/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Angel Zeininger
- Department of Evolutionary Anthropology; Duke University; Box 90383 Durham North Carolina 27708
| | - Liza J. Shapiro
- Department of Anthropology; The University of Texas at Austin; 2201 Speedway C3200 Austin Texas 78712
| | - David A. Raichlen
- School of Anthropology; The University of Arizona; 1009 E. South Campus Dr Tucson Arizona 85721
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Orr CM. Locomotor Hand Postures, Carpal Kinematics During Wrist Extension, and Associated Morphology in Anthropoid Primates. Anat Rec (Hoboken) 2016; 300:382-401. [DOI: 10.1002/ar.23507] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 06/13/2016] [Accepted: 07/20/2016] [Indexed: 11/12/2022]
Affiliation(s)
- Caley M. Orr
- Department of Cell and Developmental BiologyUniversity of Colorado School of MedicineMail Stop F435, 13001 East 17th PlaceAurora Colorado
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17
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Fontanarrosa G, Abdala V. Bone indicators of grasping hands in lizards. PeerJ 2016; 4:e1978. [PMID: 27168987 PMCID: PMC4860302 DOI: 10.7717/peerj.1978] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 04/06/2016] [Indexed: 11/20/2022] Open
Abstract
Grasping is one of a few adaptive mechanisms that, in conjunction with clinging, hooking, arm swinging, adhering, and flying, allowed for incursion into the arboreal eco-space. Little research has been done that addresses grasping as an enhanced manual ability in non-mammalian tetrapods, with the exception of studies comparing the anatomy of muscle and tendon structure. Previous studies showed that grasping abilities allow exploitation for narrow branch habitats and that this adaptation has clear osteological consequences. The objective of this work is to ascertain the existence of morphometric descriptors in the hand skeleton of lizards related to grasping functionality. A morphological matrix was constructed using 51 morphometric variables in 278 specimens, from 24 genera and 13 families of Squamata. To reduce the dimensions of the dataset and to organize the original variables into a simpler system, three PCAs (Principal Component Analyses) were performed using the subsets of (1) carpal variables, (2) metacarpal variables, and (3) phalanges variables. The variables that demonstrated the most significant contributions to the construction of the PCA synthetic variables were then used in subsequent analyses. To explore which morphological variables better explain the variations in the functional setting, we ran Generalized Linear Models for the three different sets. This method allows us to model the morphology that enables a particular functional trait. Grasping was considered the only response variable, taking the value of 0 or 1, while the original variables retained by the PCAs were considered predictor variables. Our analyses yielded six variables associated with grasping abilities: two belong to the carpal bones, two belong to the metacarpals and two belong to the phalanges. Grasping in lizards can be performed with hands exhibiting at least two different independently originated combinations of bones. The first is a combination of a highly elongated centrale bone, reduced palmar sesamoid, divergence angles above 90°, and slender metacarpal V and phalanges, such as exhibited by Anolis sp. and Tropidurus sp. The second includes an elongated centrale bone, lack of a palmar sesamoid, divergence angles above 90°, and narrow metacarpal V and phalanges, as exhibited by geckos. Our data suggest that the morphological distinction between graspers and non-graspers is demonstrating the existence of ranges along the morphological continuum within which a new ability is generated. Our results support the hypothesis of the nested origin of grasping abilities within arboreality. Thus, the manifestation of grasping abilities as a response to locomotive selective pressure in the context of narrow-branch eco-spaces could also enable other grasping-dependent biological roles, such as prey handling.
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Affiliation(s)
| | - Virginia Abdala
- Instituto de Biodiversidad Neotropical, UNT- CONICET, Tucuman, Argentina
- Facultad de Ciencias Naturales e IML, UNT, Cátedra de Biología General, Tucuman, Argentina
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Morphological Diversity in the Digital Rays of Primate Hands. DEVELOPMENTS IN PRIMATOLOGY: PROGRESS AND PROSPECTS 2016. [DOI: 10.1007/978-1-4939-3646-5_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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19
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Patterns, Variability, and Flexibility of Hand Posture During Locomotion in Primates. DEVELOPMENTS IN PRIMATOLOGY: PROGRESS AND PROSPECTS 2016. [DOI: 10.1007/978-1-4939-3646-5_13] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Fernández PJ, Almécija S, Patel BA, Orr CM, Tocheri MW, Jungers WL. Functional aspects of metatarsal head shape in humans, apes, and Old World monkeys. J Hum Evol 2015; 86:136-46. [DOI: 10.1016/j.jhevol.2015.06.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 05/26/2015] [Accepted: 06/08/2015] [Indexed: 11/28/2022]
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21
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Frost SR, Gilbert CC, Pugh KD, Guthrie EH, Delson E. The Hand of Cercopithecoides williamsi (Mammalia, Primates): Earliest Evidence for Thumb Reduction among Colobine Monkeys. PLoS One 2015; 10:e0125030. [PMID: 25993410 PMCID: PMC4439063 DOI: 10.1371/journal.pone.0125030] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 03/20/2015] [Indexed: 11/25/2022] Open
Abstract
Thumb reduction is among the most important features distinguishing the African and Asian colobines from each other and from other Old World monkeys. In this study we demonstrate that the partial skeleton KNM-ER 4420 from Koobi Fora, Kenya, dated to 1.9 Ma and assigned to the Plio-Pleistocene colobine species Cercopithecoides williamsi, shows marked reduction of its first metacarpal relative to the medial metacarpals. Thus, KNM-ER 4420 is the first documented occurrence of cercopithecid pollical reduction in the fossil record. In the size of its first metacarpal relative to the medial metacarpals, C. williamsi is similar to extant African colobines, but different from cercopithecines, extant Asian colobines and the Late Miocene colobines Microcolobus and Mesopithecus. This feature clearly links the genus Cercopithecoides with the extant African colobine clade and makes it the first definitive African colobine in the fossil record. The postcranial adaptations to terrestriality in Cercopithecoides are most likely secondary, while ancestral colobinans (and colobines) were arboreal. Finally, the absence of any evidence for pollical reduction in Mesopithecus implies either independent thumb reduction in African and Asian colobines or multiple colobine dispersal events out of Africa. Based on the available evidence, we consider the first scenario more likely.
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Affiliation(s)
- Stephen R. Frost
- Department of Anthropology, 1218 University of Oregon, Eugene, Oregon, 97403–1218, United States of America
| | - Christopher C. Gilbert
- Department of Anthropology, Hunter College of the City University of New York, New York, New York, 10065, United States of America
- New York Consortium in Evolutionary Primatology, New York, New York, 10024, United States of America
- PhD Program in Anthropology, The Graduate Center, City University of New York, New York, New York, 10016, United States of America
| | - Kelsey D. Pugh
- New York Consortium in Evolutionary Primatology, New York, New York, 10024, United States of America
- PhD Program in Anthropology, The Graduate Center, City University of New York, New York, New York, 10016, United States of America
| | - Emily H. Guthrie
- Department of Anthropology, 1218 University of Oregon, Eugene, Oregon, 97403–1218, United States of America
- Human Subjects Division, University of Washington, Seattle, Washington, 98185, United States of America
| | - Eric Delson
- New York Consortium in Evolutionary Primatology, New York, New York, 10024, United States of America
- PhD Program in Anthropology, The Graduate Center, City University of New York, New York, New York, 10016, United States of America
- Department of Vertebrate Paleontology, American Museum of Natural History, New York, New York, 10024, United States of America
- Department of Anthropology, Lehman College, City University of New York, Bronx, New York, 10468, United States of America
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22
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Matarazzo SA. Trabecular architecture of the manual elements reflects locomotor patterns in primates. PLoS One 2015; 10:e0120436. [PMID: 25793781 PMCID: PMC4368714 DOI: 10.1371/journal.pone.0120436] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 01/22/2015] [Indexed: 11/18/2022] Open
Abstract
The morphology of trabecular bone has proven sensitive to loading patterns in the long bones and metacarpal heads of primates. It is expected that we should also see differences in the manual digits of primates that practice different methods of locomotion. Primate proximal and middle phalanges are load-bearing elements that are held in different postures and experience different mechanical strains during suspension, quadrupedalism, and knuckle walking. Micro CT scans of the middle phalanx, proximal phalanx and the metacarpal head of the third ray were used to examine the pattern of trabecular orientation in Pan, Gorilla, Pongo, Hylobates and Macaca. Several zones, i.e., the proximal ends of both phalanges and the metacarpal heads, were capable of distinguishing between knuckle-walking, quadrupedal, and suspensory primates. Orientation and shape seem to be the primary distinguishing factors but differences in bone volume, isotropy index, and degree of anisotropy were seen across included taxa. Suspensory primates show primarily proximodistal alignment in all zones, and quadrupeds more palmar-dorsal orientation in several zones. Knuckle walkers are characterized by having proximodistal alignment in the proximal ends of the phalanges and a palmar-dorsal alignment in the distal ends and metacarpal heads. These structural differences may be used to infer locmotor propensities of extinct primate taxa.
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Affiliation(s)
- Stacey A. Matarazzo
- Anthropology Department, University of Massachusetts at Amherst, Massachusetts, United States of America
- * E-mail:
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23
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Lewton KL. Pelvic Form and Locomotor Adaptation in Strepsirrhine Primates. Anat Rec (Hoboken) 2014; 298:230-48. [DOI: 10.1002/ar.23070] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 10/11/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Kristi L. Lewton
- Department of Anatomy and Neurobiology; Boston University School of Medicine; Boston Massachusetts
- Department of Human Evolutionary Biology; Harvard University; Cambridge Massachusetts
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24
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Rein TR, Harvati K. Exploring third metacarpal capitate facet shape in early hominins. Anat Rec (Hoboken) 2012; 296:240-9. [PMID: 23233292 DOI: 10.1002/ar.22635] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 09/17/2012] [Accepted: 10/22/2012] [Indexed: 11/06/2022]
Abstract
The joint between the capitate and third metacarpal plays an important role in stabilizing the manus during hand use in great apes and humans. Researchers have examined the morphology of this region in humans, our fossil relatives, and other extant primates to try to understand the importance of this joint in human evolution. The first goal of our research was to explore shape variation of the third metacarpal capitate facet across extant anthropoids, including hominoids, cercopithecoids, and platyrrhines. This analysis allowed us to examine the range of variation in the capitate facet and the degree to which locomotor behavior, phylogeny, and size explained shape variation. We also examined capitate facet shape in the early hominin fossil record in order to explore how the shape of this articular surface has changed during early hominin evolution. We captured six landmark coordinates on the edge of the capitate facet in extant anthropoids and fossil specimens to quantify and visualize shape variation in this region. We used principal components analysis, Procrustes distances, and multivariate regression analysis to investigate different possible influences on shape variation. We found that shape variation corresponded to function, phylogeny, and size. With the exception of brachiation, shape variation did not clearly correspond with any specific locomotor behavior. However, we identified a shift in the relative mediolateral breadth of the capitate facet during early hominin evolution, which is most likely one of several adaptations for a more stable joint surface.
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Affiliation(s)
- Thomas R Rein
- Department of Early Prehistory and Quaternary Ecology, Paleoanthropology Section, Senckenberg Center for Human Evolution and Paleoecology, Eberhard Karls Universität Tübingen, Rümelinstr. 23, 72070 Tübingen, Germany.
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25
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Rein TR, McCarty LA. Metacarpophalangeal Joint Orientation in Anthropoid Manual Phalanges. Anat Rec (Hoboken) 2012; 295:2057-68. [DOI: 10.1002/ar.22600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Accepted: 07/20/2012] [Indexed: 11/08/2022]
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26
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Sylvester AD, Pfisterer T. Quantifying lateral femoral condyle ellipticalness in chimpanzees, gorillas, and humans. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2012; 149:458-67. [DOI: 10.1002/ajpa.22144] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 08/20/2012] [Indexed: 11/09/2022]
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27
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Patel BA, Larson SG, Stern JT. Electromyography of wrist and finger flexor muscles in olive baboons (Papio anubis). J Exp Biol 2012; 215:115-23. [DOI: 10.1242/jeb.063107] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Some non-human primates use digitigrade hand postures when walking slowly on the ground. As a component of an extended limb, a digitigrade posture can help minimize wrist joint moments thereby requiring little force production directly from wrist flexors (and/or from the assistance of finger flexors) to maintain limb posture. As a consequence, less active muscle volume would be required from these anti-gravity muscles and overall metabolic costs associated with locomotion could be reduced. To investigate whether the use of digitigrade hand postures during walking in primates entails minimal use of anti-gravity muscles, this study examined electromyography (EMG) patterns in both the wrist and finger flexor muscles in facultatively digitigrade olive baboons (Papio anubis) across a range of speeds. The results demonstrate that baboons can adopt a digitigrade hand posture when standing and moving at slow speeds without requiring substantial EMG activity from distal anti-gravity muscles. Higher speed locomotion, however, entails increasing EMG activity and is accompanied by a dynamic shift to a more palmigrade-like limb posture. Thus, the ability to adopt a digitigrade hand posture by monkeys is an adaptation for ground living, but it was never co-opted for fast locomotion. Rather, digitigrady in primates appears to be related to energetic efficiency for walking long distances.
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Affiliation(s)
- Biren A. Patel
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794-8081, USA
| | - Susan G. Larson
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794-8081, USA
| | - Jack T. Stern
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794-8081, USA
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