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Powell VCR, Barr WA, Hammond AS, Wood BA. Behavioral and phylogenetic correlates of limb length proportions in extant apes and monkeys: Implications for interpreting hominin fossils. J Hum Evol 2024; 190:103494. [PMID: 38564844 DOI: 10.1016/j.jhevol.2024.103494] [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: 06/12/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 04/04/2024]
Abstract
The body proportions of extant animals help inform inferences about the behaviors of their extinct relatives, but relationships between body proportions, behavior, and phylogeny in extant primates remain unclear. Advances in behavioral data, molecular phylogenies, and multivariate analytical tools make it an opportune time to perform comprehensive comparative analyses of primate traditional limb length proportions (e.g., intermembral, humerofemoral, brachial, and crural indices), body size-adjusted long bone proportions, and principal components. In this study we used a mix of newly-collected and published data to investigate whether and how the limb length proportions of a diverse sample of primates, including monkeys, apes, and modern humans, are influenced by behavior and phylogeny. We reconfirm that the intermembral index, followed by the first principal component of traditional limb length proportions, is the single most effective variable distinguishing hominoids and other anthropoids. Combined limb length proportions and positional behaviors are strongly correlated in extant anthropoid groups, but phylogeny is a better predictor of limb length proportion variation than of behavior. We confirm convergences between members of the Atelidae and extant apes (especially Pan), members of the Hylobatidae and Pongo, and a potential divergence of Presbytis limb proportions from some other cercopithecoids, which correlate with adaptations for forelimb-dominated behaviors in some colobines. Collectively, these results substantiate hypotheses indicating that extinct hominins and other hominoid taxa can be distinguished by analyzing combinations of their limb length proportions at different taxonomic levels. From these results, we hypothesize that fossil skeletons characterized by notably disparate limb length proportions are unlikely to have exhibited similar behavioral patterns.
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Affiliation(s)
- Vance C R Powell
- Department of Anatomy, Howard University College of Medicine, 520 W St. N.W., Washington, D.C., 20059, USA; Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, D.C., 20052, USA.
| | - W Andrew Barr
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, D.C., 20052, USA
| | - Ashley S Hammond
- Division of Anthropology, American Museum of Natural History (AMNH), New York, N.Y., 10024, USA; New York Consortium in Evolutionary Primatology at AMNH, New York, N.Y., 10024, USA
| | - Bernard A Wood
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, D.C., 20052, USA
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Harper CM, Patel BA. Trabecular bone variation in the gorilla calcaneus. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024:e24939. [PMID: 38631677 DOI: 10.1002/ajpa.24939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 02/15/2024] [Accepted: 04/02/2024] [Indexed: 04/19/2024]
Abstract
OBJECTIVES Calcaneal external shape differs among nonhuman primates relative to locomotion. Such relationships between whole-bone calcaneal trabecular structure and locomotion, however, have yet to be studied. Here we analyze calcaneal trabecular architecture in Gorilla gorilla gorilla, Gorilla beringei beringei, and G. b. graueri to investigate general trends and fine-grained differences among gorilla taxa relative to locomotion. MATERIALS AND METHODS Calcanei were micro-CT scanned. A three-dimensional geometric morphometric sliding semilandmark analysis was carried out and the final landmark configurations used to position 156 volumes of interest. Trabecular thickness (Tb.Th), trabecular spacing (Tb.Sp), and bone volume fraction (BV/TV) were calculated using the BoneJ plugin for ImageJ and MATLAB. Non-parametric MANOVAs were run to test for significant differences among taxa in parameter raw values and z-scores. Parameter distributions were visualized using color maps and summarized using principal components analysis. RESULTS There are no significant differences in raw BV/TV or Tb.Th among gorillas, however G. b. beringei significantly differs in z-scores for both parameters (p = <0.0271). All three taxa exhibit relatively lower BV/TV and Tb.Th in the posterior half of the calcaneus. This gradation is exacerbated in G. b. beringei. G. b. graueri significantly differs from other taxa in Tb.Sp z-scores (p < 0.001) indicating a different spacing distribution. DISCUSSION Relatively higher Tb.Th and BV/TV in the anterior calcaneus among gorillas likely reflects higher forces associated with body mass (transmitted through the subtalar joint) relative to forces transferred through the posterior calcaneus. The different Tb.Sp pattern in G. b. graueri may reflect proposed differences in foot positioning during locomotion.
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Affiliation(s)
- Christine M Harper
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, New Jersey, USA
| | - Biren A Patel
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- Human and Evolutionary Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
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Bleuze MM. Changes in limb bone diaphyseal structure in chimpanzees during development. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024:e24942. [PMID: 38602254 DOI: 10.1002/ajpa.24942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 02/24/2024] [Accepted: 04/02/2024] [Indexed: 04/12/2024]
Abstract
OBJECTIVES This study tests if femoral and humeral cross-sectional geometry (CSG) and cross-sectional properties (CSPs) in an ontogenetic series of wild-caught chimpanzees (Pan troglodytes ssp.) reflect locomotor behavior during development. The goal is to clarify the relationship between limb bone structure and locomotor behavior during ontogeny in Pan. MATERIALS AND METHODS The latex cast method was used to reconstruct cross sections at the midshaft femur and mid-distal humerus. Second moments of area (SMAs) (Ix, Iy, Imax, Imin), which are proportional to bending rigidity about a specified axis, and the polar SMA (J), which is proportional to average bending rigidity, were calculated at section locations. Cross-sectional shape (CSS) was assessed from Ix/Iy and Imax/Imin ratios. Juvenile and adult subsamples were compared. RESULTS Juveniles and adults have significantly greater femoral J compared to humeral J. Mean interlimb proportions of J are not significantly different between the groups. There is an overall decreasing trend in diaphyseal circularity between the juvenile phase of development and adulthood, although significant differences are only found in the humerus. DISCUSSION Juvenile chimpanzee locomotion includes forelimb- and hindlimb-biased behaviors. Juveniles and adults preferentially load their hindlimbs relative to their forelimbs. This may indicate similar locomotor behavior, although other explanations including a diversity of hindlimb-biased locomotor behaviors in juveniles cannot be ruled out. Different ontogenetic trends in forelimb and hindlimb CSS are consistent with limb bone CSG reflecting functional adaptation, albeit the complex nature of bone functional adaptation requires cautious interpretations of skeletal functional morphology from biomechanical analyses.
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Affiliation(s)
- Michele M Bleuze
- Institutional affiliation: Department of Anthropology, California State University Los Angeles, Los Angeles, California, USA
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Kralick AE, Zemel BS, Nolan C, Lin P, Tocheri MW. Relative leg-to-arm skeletal strength proportions in orangutans by species and sex. J Hum Evol 2024; 188:103496. [PMID: 38412694 DOI: 10.1016/j.jhevol.2024.103496] [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: 04/25/2023] [Revised: 01/02/2024] [Accepted: 01/05/2024] [Indexed: 02/29/2024]
Abstract
Among extant great apes, orangutans climb most frequently. However, Bornean orangutans (Pongo pygmaeus) exhibit higher frequencies of terrestrial locomotion than do Sumatran orangutans (Pongo abelii). Variation in long bone cross-sectional geometry is known to reflect differential loading of the limbs. Thus, Bornean orangutans should show greater relative leg-to-arm strength than their Sumatran counterparts. Using skeletal specimens from museum collections, we measured two cross-sectional geometric measures of bone strength: the polar section modulus (Zpol) and the ratio of maximum to minimum area moments of inertia (Imax/Imin), at the midshaft of long bones in Bornean (n = 19) and Sumatran adult orangutans (n = 12) using medical CT and peripheral quantitative CT scans, and compared results to published data of other great apes. Relative leg-to-arm strength was quantified using ratios of femur and tibia over humerus, radius, and ulna, respectively. Differences between orangutan species and between sexes in median ratios were assessed using Wilcoxon rank sum tests. The tibia of Bornean orangutans was stronger relative to the humerus and the ulna than in Sumatran orangutans (p = 0.008 and 0.025, respectively), consistent with behavioral studies that indicate higher frequencies of terrestrial locomotion in the former. In three Zpol ratios, adult female orangutans showed greater leg-to-arm bone strength compared to flanged males, which may relate to females using their legs more during arboreal locomotion than in adult flanged males. A greater amount of habitat discontinuity on Borneo compared to Sumatra has been posited as a possible explanation for observed interspecific differences in locomotor behaviors, but recent camera trap studies has called this into question. Alternatively, greater frequencies of terrestriality in Pongo pygmaeus may be due to the absence of tigers on Borneo. The results of this study are consistent with the latter explanation given that habitat continuity was greater a century ago when our study sample was collected.
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Affiliation(s)
- Alexandra E Kralick
- Studies of Women, Gender, and Sexuality, Harvard University, Cambridge, 02138, USA; Department of Anthropology, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, USA.
| | - Babette S Zemel
- Division of Gastroenterology, Hepatology and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA; Department of Pediatrics, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA
| | - Clara Nolan
- Fine Arts Department, University of Pennsylvania, Philadelphia, PA, 19104, USA; Department of Computer and Information Science, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Phillip Lin
- Stockdale High School, Bakersfield, CA, 93311, USA
| | - 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, D.C., 20013, USA; Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, University of Wollongong, Wollongong, New South Wales, NSW, 2522, Australia
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Alfieri F, Botton-Divet L, Wölfer J, Nyakatura JA, Amson E. A macroevolutionary common-garden experiment reveals differentially evolvable bone organization levels in slow arboreal mammals. Commun Biol 2023; 6:995. [PMID: 37770611 PMCID: PMC10539518 DOI: 10.1038/s42003-023-05371-3] [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: 02/20/2023] [Accepted: 09/18/2023] [Indexed: 09/30/2023] Open
Abstract
Eco-morphological convergence, i.e., similar phenotypes evolved in ecologically convergent taxa, naturally reproduces a common-garden experiment since it allows researchers to keep ecological factors constant, studying intrinsic evolutionary drivers. The latter may result in differential evolvability that, among individual anatomical parts, causes mosaic evolution. Reconstructing the evolutionary morphology of the humerus and femur of slow arboreal mammals, we addressed mosaicism at different bone anatomical spatial scales. We compared convergence strength, using it as indicator of evolvability, between bone external shape and inner structure, with the former expected to be less evolvable and less involved in convergent evolution, due to anatomical constraints. We identify several convergent inner structural traits, while external shape only loosely follows this trend, and we find confirmation for our assumption in measures of convergence magnitude. We suggest that future macroevolutionary reconstructions based on bone morphology should include structural traits to better detect ecological effects on vertebrate diversification.
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Affiliation(s)
- Fabio Alfieri
- Comparative Zoology, Institute for Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, 10117, Berlin, Germany.
- Museum Für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, 10115, Berlin, Germany.
| | - Léo Botton-Divet
- Comparative Zoology, Institute for Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, 10117, Berlin, Germany
| | - Jan Wölfer
- Comparative Zoology, Institute for Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, 10117, Berlin, Germany
| | - John A Nyakatura
- Comparative Zoology, Institute for Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, 10117, Berlin, Germany
| | - Eli Amson
- Paleontology Department, Staatliches Museum für Naturkunde, Rosenstein 1-3, 70191, Stuttgart, Germany
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Rickman J, Burtner AE, Linden TJ, Santana SE, Law CJ. Size And Locomotor Ecology Have Differing Effects on the External and Internal Morphologies of Squirrel (Rodentia: Sciuridae) Limb Bones. Integr Org Biol 2023; 5:obad017. [PMID: 37361915 PMCID: PMC10286724 DOI: 10.1093/iob/obad017] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 04/19/2023] [Accepted: 05/10/2023] [Indexed: 06/28/2023] Open
Abstract
Mammals exhibit a diverse range of limb morphologies that are associated with different locomotor ecologies and structural mechanics. Much remains to be investigated, however, about the combined effects of locomotor modes and scaling on the external shape and structural properties of limb bones. Here, we used squirrels (Sciuridae) as a model clade to examine the effects of locomotor mode and scaling on the external shape and structure of the two major limb bones, the humerus and femur. We quantified humeral and femoral morphologies using 3D geometric morphometrics and bone structure analyses on a sample of 76 squirrel species across their four major ecotypes. We then used phylogenetic generalized linear models to test how locomotor ecology, size, and their interaction influenced morphological traits. We found that size and locomotor mode exhibit different relationships with the external shape and structure of the limb bones, and that these relationships differ between the humerus and femur. External shapes of the humerus and, to a lesser extent, the femur are best explained by locomotor ecology rather than by size, whereas structures of both bones are best explained by interactions between locomotor ecology and scaling. Interestingly, the statistical relationships between limb morphologies and ecotype were lost when accounting for phylogenetic relationships among species under Brownian motion. That assuming Brownian motion confounded these relationships is not surprising considering squirrel ecotypes are phylogenetically clustered; our results suggest that humeral and femoral variation partitioned early between clades and their ecomorphologies were maintained to the present. Overall, our results show how mechanical constraints, locomotor ecology, and evolutionary history may enact different pressures on the shape and structure of limb bones in mammals.
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Affiliation(s)
| | | | - T J Linden
- Department of Biology and Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98105, USA
| | - S E Santana
- Department of Biology and Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98105, USA
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Sarringhaus L, Lewton KL, Iqbal S, Carlson KJ. Ape femoral-humeral rigidities and arboreal locomotion. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2022; 179:624-639. [PMID: 36790629 PMCID: PMC9828227 DOI: 10.1002/ajpa.24632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 06/29/2022] [Accepted: 09/13/2022] [Indexed: 11/07/2022]
Abstract
OBJECTIVES This study investigates patterns of bone functional adaptations in extant apes through comparing hindlimb to forelimb bone rigidity ratios in groups with varying levels of arboreality. MATERIALS AND METHODS Using CT scans, bone rigidity (J) was calculated at three regions of interest (ROI) along femoral and humeral diaphyses in Homo, Pongo, Pan, and Gorilla with further comparisons made between species and subspecies divisions within Pan and Gorilla. RESULTS Consistent with previous work on extant hominoids, species exhibited differences in midshaft femoral to humeral (F/H) rigidity ratios. Results of the present study confirm that these midshaft differences extend to 35% and 65% diaphyseal ROIs. Modern humans, exhibiting larger ratios, and orangutans, exhibiting smaller ratios, bracketed the intermediate African apes in comparisons. Within some African apes, limb rigidity ratios varied significantly between taxonomic groups. Eastern gorillas exhibited the highest mean ratios and chimpanzees the lowest at all three ROIs. In posthoc comparisons, chimpanzees and bonobos did not differ in relative limb rigidity ratios at any of the three ROIs. However, western gorillas were more similar to bonobos than eastern gorillas at 50% and 35% ROIs, but not at the 65% ROI. CONCLUSION Species, and to a lesser extent subspecies, can be distinguished by F/H limb rigidity ratios according to broad positional behavior patterns at multiple regions of interest along the diaphyses. Similarity of bonobos and western gorillas is in line with behavioral data of bonobos being the most terrestrial of Pan species, and western gorillas the most arboreal of the Gorilla groups.
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Affiliation(s)
- Lauren Sarringhaus
- Department of Evolutionary AnthropologyDuke UniversityDurhamNorth CarolinaUSA,Department of AnthropologyUniversity of MichiganAnn ArborMichiganUSA,Department of BiologyJames Madison UniversityHarrisonburgVirginiaUSA
| | - Kristi L. Lewton
- Department of Integrative Anatomical Sciences, Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Safiyyah Iqbal
- School of Animal, Plant and Environmental SciencesUniversity of the WitwatersrandJohannesburgSouth Africa
| | - Kristian J. Carlson
- Department of Integrative Anatomical Sciences, Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCaliforniaUSA,Evolutionary Studies InstituteUniversity of the WitwatersrandJohannesburgSouth Africa
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Laitman JT, Smith HF. The Anatomical Record explores the soul of the anatomical sciences in a groundbreaking special issue: "Evolution of a discipline, the changing face of anatomy". Anat Rec (Hoboken) 2022; 305:762-765. [PMID: 35192241 DOI: 10.1002/ar.24898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 02/08/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Jeffrey T Laitman
- Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Heather F Smith
- Department of Anatomy, Midwestern University, Glendale, Arizona, USA.,School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona, USA
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Integrative Approach Uncovers New Patterns of Ecomorphological Convergence in Slow Arboreal Xenarthrans. J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09590-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractIdentifying ecomorphological convergence examples is a central focus in evolutionary biology. In xenarthrans, slow arboreality independently arose at least three times, in the two genera of ‘tree sloths’, Bradypus and Choloepus, and the silky anteater, Cyclopes. This specialized locomotor ecology is expectedly reflected by distinctive morpho-functional convergences. Cyclopes, although sharing several ecological features with ‘tree sloths’, do not fully mirror the latter in their outstandingly similar suspensory slow arboreal locomotion. We hypothesized that the morphology of Cyclopes is closer to ‘tree sloths’ than to anteaters, but yet distinct, entailing that slow arboreal xenarthrans evolved through ‘incomplete’ convergence. In a multivariate trait space, slow arboreal xenarthrans are hence expected to depart from their sister taxa evolving toward the same area, but not showing extensive phenotypical overlap, due to the distinct position of Cyclopes. Conversely, a pattern of ‘complete’ convergence (i.e., widely overlapping morphologies) is hypothesized for ‘tree sloths’. Through phylogenetic comparative methods, we quantified humeral and femoral convergence in slow arboreal xenarthrans, including a sample of extant and extinct non-slow arboreal xenarthrans. Through 3D geometric morphometrics, cross-sectional properties (CSP) and trabecular architecture, we integratively quantified external shape, diaphyseal anatomy and internal epiphyseal structure. Several traits converged in slow arboreal xenarthrans, especially those pertaining to CSP. Phylomorphospaces and quantitative convergence analyses substantiated the expected patterns of ‘incomplete’ and ‘complete’ convergence for slow arboreal xenarthrans and ‘tree sloths’, respectively. This work, highlighting previously unidentified convergence patterns, emphasizes the value of an integrative multi-pronged quantitative approach to cope with complex mechanisms underlying ecomorphological convergence.
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Amson E, Bibi F. Differing effects of size and lifestyle on bone structure in mammals. BMC Biol 2021; 19:87. [PMID: 33926429 PMCID: PMC8086358 DOI: 10.1186/s12915-021-01016-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 04/01/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Mammals are a highly diverse group, with body mass ranging from 2 g to 170 t, and encompassing species with terrestrial, aquatic, aerial, and subterranean lifestyles. The skeleton is involved in most aspects of vertebrate life history, but while previous macroevolutionary analyses have shown that structural, phylogenetic, and functional factors influence the gross morphology of skeletal elements, their inner structure has received comparatively little attention. Here we analysed bone structure of the humerus and mid-lumbar vertebrae across mammals and their correlations with different lifestyles and body size. RESULTS We acquired bone structure parameters in appendicular and axial elements (humerus and mid-lumbar vertebra) from 190 species across therian mammals (placentals + marsupials). Our sample captures all transitions to aerial, fully aquatic, and subterranean lifestyles in extant therian clades. We found that mammalian bone structure is highly disparate and we show that the investigated vertebral structure parameters mostly correlate with body size, but not lifestyle, while the opposite is true for humeral parameters. The latter also show a high degree of convergence among the clades that have acquired specialised (non-terrestrial) lifestyles. CONCLUSIONS In light of phylogenetic, size, and functional factors, the distribution of each investigated structural parameter reveals patterns explaining the construction of appendicular and axial skeletal elements in mammalian species spanning most of the extant diversity of the clade in terms of body size and lifestyle. These patterns should be further investigated with analyses focused on specific lifestyle transitions that would ideally include key fossils.
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Affiliation(s)
- Eli Amson
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115, Berlin, Germany.
- Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, 70191, Stuttgart, Germany.
| | - Faysal Bibi
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115, Berlin, Germany
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11
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Mossor AM, Austin BL, Avey-Arroyo JA, Butcher MT. A Horse of a Different Color?: Tensile Strength and Elasticity of Sloth Flexor Tendons. Integr Org Biol 2021; 2:obaa032. [PMID: 33796818 DOI: 10.1093/iob/obaa032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tendons must be able to withstand the tensile forces generated by muscles to provide support while avoiding failure. The properties of tendons in mammal limbs must therefore be appropriate to accommodate a range of locomotor habits and posture. Tendon collagen composition provides resistance to loading that contributes to tissue strength which could, however, be modified to not exclusively confer large strength and stiffness for elastic energy storage/recovery. For example, sloths are nearly obligate suspenders and cannot run, and due to their combined low metabolic rate, body temperature, and rate of digestion, they have an extreme need to conserve energy. It is possible that sloths have a tendon "suspensory apparatus" functionally analogous to that in upright ungulates, thus allowing for largely passive support of their body weight below-branch, while concurrently minimizing muscle contractile energy expenditure. The digital flexor tendons from the fore- and hindlimbs of two-toed (Choloepus hoffmanni) and three-toed (Bradypus variegatus) sloths were loaded in tension until failure to test this hypothesis. Overall, tensile strength and elastic (Young's) modulus of sloth tendons were low, and these material properties were remarkably similar to those of equine suspensory "ligaments." The results also help explain previous findings in sloths showing relatively low levels of muscle activation in the digital flexors during postural suspension and suspensory walking.
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Affiliation(s)
- A M Mossor
- Department of Biological Sciences, Youngstown State University, Youngstown, OH USA
| | - B L Austin
- Department of Biological Sciences, Youngstown State University, Youngstown, OH USA
| | | | - M T Butcher
- Department of Biological Sciences, Youngstown State University, Youngstown, OH USA
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López‐Aguirre C, Wilson LAB, Koyabu D, Tu VT, Hand SJ. Variation in cross‐sectional shape and biomechanical properties of the bat humerus under Wolff's law. Anat Rec (Hoboken) 2021; 304:1937-1952. [DOI: 10.1002/ar.24620] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 02/10/2021] [Accepted: 02/17/2021] [Indexed: 11/12/2022]
Affiliation(s)
- Camilo López‐Aguirre
- Earth and Sustainability Science Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales Sydney New South Wales Australia
| | - Laura A. B. Wilson
- Earth and Sustainability Science Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales Sydney New South Wales Australia
- School of Archaeology and Anthropology, Australian National University Canberra ACT Australia
| | - Daisuke Koyabu
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong Kowloon Hong Kong
- Department of Molecular Craniofacial Embryology Tokyo Medical and Dental University Tokyo Japan
| | - Vuong Tan Tu
- Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology Hanoi Vietnam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology Hanoi Vietnam
| | - Suzanne J. Hand
- Earth and Sustainability Science Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales Sydney New South Wales Australia
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López-Aguirre C, Hand SJ, Koyabu D, Tu VT, Wilson LAB. Phylogeny and foraging behaviour shape modular morphological variation in bat humeri. J Anat 2020; 238:1312-1329. [PMID: 33372711 DOI: 10.1111/joa.13380] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 11/19/2020] [Accepted: 11/20/2020] [Indexed: 01/18/2023] Open
Abstract
Bats show a remarkable ecological diversity that is reflected both in dietary and foraging guilds (FGs). Cranial ecomorphological adaptations linked to diet have been widely studied in bats, using a variety of anatomical, computational and mathematical approaches. However, foraging-related ecomorphological adaptations and the concordance between cranial and postcranial morphological adaptations remain unexamined in bats and limited to the interpretation of traditional aerodynamic properties of the wing (e.g. wing loading [WL] and aspect ratio [AR]). For this reason, the postcranial ecomorphological diversity in bats and its drivers remain understudied. Using 3D virtual modelling and geometric morphometrics (GMM), we explored the phylogenetic, ecological and biological drivers of humeral morphology in bats, evaluating the presence and magnitude of modularity and integration. To explore decoupled patterns of variation across the bone, we analysed whole-bone shape, diaphyseal and epiphyseal shape. We also tested whether traditional aerodynamic wing traits correlate with humeral shape. By studying 37 species from 20 families (covering all FGs and 85% of dietary guilds), we found similar patterns of variation in whole-bone and diaphyseal shape and unique variation patterns in epiphyseal shape. Phylogeny, diet and FG significantly correlated with shape variation at all levels, whereas size only had a significant effect on epiphyseal morphology. We found a significant phylogenetic signal in all levels of humeral shape. Epiphyseal shape significantly correlated with wing AR. Statistical support for a diaphyseal-epiphyseal modular partition of the humerus suggests a functional partition of shape variability. Our study is the first to show within-structure modular morphological variation in the appendicular skeleton of any living tetrapod. Our results suggest that diaphyseal shape correlates more with phylogeny, whereas epiphyseal shape correlates with diet and FG.
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Affiliation(s)
- Camilo López-Aguirre
- Earth and Sustainability Science Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Suzanne J Hand
- Earth and Sustainability Science Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Daisuke Koyabu
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong.,Department of Molecular Craniofacial Embryology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Vuong Tan Tu
- Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, Hanoi, Vietnam.,Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Laura A B Wilson
- Earth and Sustainability Science Research Centre, School of Biological, Earth & Environmental Sciences, University of New South Wales, Sydney, NSW, Australia.,School of Archaeology & Anthropology, Australian National University, Canberra, ACT, Australia
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14
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Nadell JA, Elton S, Kovarovic K. Ontogenetic and morphological variation in primate long bones reflects signals of size and behavior. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2020; 174:327-351. [PMID: 33368154 DOI: 10.1002/ajpa.24198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/08/2020] [Accepted: 11/19/2020] [Indexed: 11/05/2022]
Abstract
OBJECTIVES Many primates change their locomotor behavior as they mature from infancy to adulthood. Here we investigate how long bone cross-sectional geometry in Pan, Gorilla, Pongo, Hylobatidae, and Macaca varies in shape and form over ontogeny, including whether specific diaphyseal cross sections exhibit signals of periosteal adaptation or canalization. MATERIALS AND METHODS Diaphyseal cross sections were analyzed in an ontogenetic series across infant, juvenile, and adult subgroups. Three-dimensional laser-scanned long bone models were sectioned at midshaft (50% of biomechanical length) and distally (20%) along the humerus and femur. Traditional axis ratios acted as indices of cross-sectional circularity, while geometric morphometric techniques were used to study cross-sectional allometry and ontogenetic trajectory. RESULTS The humeral midshaft is a strong indicator of posture and locomotor profile in the sample across development, while the mid-femur appears more reflective of shifts in size. By comparison, the distal diaphyses of both limb elements are more ontogenetically constrained, where periosteal shape is largely static across development relative to size, irrespective of a given taxon's behavior or ecology. DISCUSSION Primate limb shape is not only highly variable between taxa over development, but at discrete humeral and femoral diaphyseal locations. Overall, periosteal shape of the humeral and femoral midshaft cross sections closely reflects ontogenetic transitions in behavior and size, respectively, while distal shape in both bones appears more genetically constrained across intraspecific development, regardless of posture or size. These findings support prior research on tradeoffs between function and safety along the limbs.
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Affiliation(s)
- Jason A Nadell
- Department of Anthropology, Durham University, Durham, United Kingdom
| | - Sarah Elton
- Department of Anthropology, Durham University, Durham, United Kingdom
| | - Kris Kovarovic
- Department of Anthropology, Durham University, Durham, United Kingdom
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15
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Profico A, Bondioli L, Raia P, O'Higgins P, Marchi D. morphomap: An R package for long bone landmarking, cortical thickness, and cross‐sectional geometry mapping. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2020; 174:129-139. [DOI: 10.1002/ajpa.24140] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 06/15/2020] [Accepted: 08/11/2020] [Indexed: 01/15/2023]
Affiliation(s)
- Antonio Profico
- PalaeoHub, Department of Archaeology University of York York UK
| | - Luca Bondioli
- Service of Bioarchaeology Service Museo delle Civiltà Rome Italy
| | - Pasquale Raia
- Dipartimento di Scienze della Terra, dell'Ambiente e delle Risorse Università di Napoli Federico II Naples Italy
| | - Paul O'Higgins
- PalaeoHub, Department of Archaeology University of York York UK
- Hull York Medical School University of York York UK
- Centre for Forensic Anthropology University of Western Australia Perth Australia
| | - Damiano Marchi
- Department of Biology University of Pisa Pisa Italy
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences University of the Witwatersrand Johannesburg‐Braamfontein South Africa
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16
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Terhune CE, Sylvester AD, Scott JE, Ravosa MJ. Internal architecture of the mandibular condyle of rabbits is related to dietary resistance during growth. J Exp Biol 2020; 223:jeb220988. [PMID: 32127379 DOI: 10.1242/jeb.220988] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 02/25/2020] [Indexed: 12/11/2022]
Abstract
Although there is considerable evidence that bone responds to the loading environment in which it develops, few analyses have examined phenotypic plasticity or bone functional adaptation in the masticatory apparatus. Prior work suggests that masticatory morphology is sensitive to differences in food mechanical properties during development; however, the importance of the timing/duration of loading and variation in naturalistic diets is less clear. Here, we examined microstructural and macrostructural differences in the mandibular condyle in four groups of white rabbits (Oryctolagus cuniculus) raised for a year on diets that varied in mechanical properties and timing of the introduction of mechanically challenging foods, simulating seasonal variation in diet. We employed sliding semilandmarks to locate multiple volumes of interest deep to the mandibular condyle articular surface, and compared bone volume fraction, trabecular thickness and spacing, and condylar size/shape among experimental groups. The results reveal a shared pattern of bony architecture across the articular surface of all treatment groups, while also demonstrating significant among-group differences. Rabbits raised on mechanically challenging diets have significantly increased bone volume fraction relative to controls fed a less challenging diet. The post-weaning timing of the introduction of mechanically challenging foods also influences architectural properties, suggesting that bone plasticity can extend well into adulthood and that bony responses to changes in loading may be rapid. These findings demonstrate that bony architecture of the mandibular condyle in rabbits responds to variation in mechanical loading during an organism's lifetime and has the potential to track dietary variation within and among species.
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Affiliation(s)
- Claire E Terhune
- Department of Anthropology, University of Arkansas, Fayetteville, AR 72701, USA
| | - Adam D Sylvester
- Center for Functional Anatomy and Evolution, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jeremiah E Scott
- Department of Medical Anatomical Sciences, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Matthew J Ravosa
- Departments of Biological Sciences, Aerospace & Mechanical Engineering, and Anthropology, University of Notre Dame, Notre Dame, IN 46556, USA
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17
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Lewton KL, Patel BA. Calcaneal elongation and bone strength in leaping galagids. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 171:430-438. [PMID: 31710709 DOI: 10.1002/ajpa.23970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 08/06/2019] [Accepted: 10/27/2019] [Indexed: 11/11/2022]
Abstract
OBJECTIVES Small-bodied vertical clinging and leaping primates have elongated calcanei which enhance leap performance by optimizing leap velocity, distance, and acceleration, but at the expense of experiencing relatively large forces during takeoff and landing. This study tests the hypothesis that the elongated calcaneus of leaping galagids is adapted to resist larger and more stereotyped bending loads compared to more quadrupedal galagids. MATERIALS AND METHODS The calcanei of 14 individuals of Otolemur and 14 individuals of Galago (three species of each genus) were μCT scanned. Calcaneal cross-sectional properties (maximum and minimum second moments of area and polar section modulus) were obtained from a slice representing the 50% position of bone segment length and dimensionless ratios were created for each variable using calcaneal cuboid facet area as a proxy for body mass. RESULTS There were no significant differences in size-adjusted bending strength between Galago and Otolemur. Galago exhibited more elliptically shaped calcaneal cross sections, however, suggesting that its calcanei are more adapted to stereotyped loading regimes than those of Otolemur. DISCUSSION The results suggest that the calcaneus of specialized leapers is adapted to more stereotyped loading patterns. The lack of predicted bone strength differences between Galago and Otolemur may be related to body size differences between these taxa, or it may indicate that loads encountered by Galago during naturalistic leaping are not reflected in the available experimental force data.
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Affiliation(s)
- Kristi L Lewton
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California.,Department of Biological Sciences, Human & Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Biren A Patel
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California.,Department of Biological Sciences, Human & Evolutionary Biology Section, University of Southern California, Los Angeles, California
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18
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Crane MA, Kato KM, Patel BA, Huttenlocker AK. Histovariability in human clavicular cortical bone microstructure and its mechanical implications. J Anat 2019; 235:873-882. [PMID: 31373387 DOI: 10.1111/joa.13056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2019] [Indexed: 12/17/2022] Open
Abstract
The human clavicle (i.e. collarbone) is an unusual long bone due to its signature S-shaped curve and variability in macrostructure observed between individuals. Because of the complex nature of how the upper limb moves, as well as due to its complex musculoskeletal arrangement, the biomechanics, in particular the mechanical loadings, of the clavicle are not fully understood. Given that bone remodeling can be influenced by bone stress, the histologic organization of Haversian bone offers a hypothesis of responses to force distributions experienced across a bone. Furthermore, circularly polarized light microscopy can be used to determine the orientation of collagen fibers, providing additional information on how bone matrix might organize to adapt to direction of external loads. We examined Haversian density and collagen fiber orientation, along with cross-sectional geometry, to test whether the clavicle midshaft shows unique adaptation to atypical load-bearing when compared with the sternal (medial) and acromial (lateral) shaft regions. Because fractures are most common at the midshaft, we predicted that the cortical bone structure would show both disparities in Haversian remodeling and nonrandomly oriented collagen fibers in the midshaft compared with the sternal and acromial regions. Human clavicles (n = 16) were sampled via thin-sections at the sternal, middle, and acromial ends of the shaft, and paired sample t-tests were employed to evaluate within-individual differences in microstructural or geometric properties. We found that Haversian remodeling is slightly but significantly reduced in the middle of the bone. Analysis of collagen fiber orientation indicated nonrandom fiber orientations that are overbuilt for tensile loads or torsion but are poorly optimized for compressive loads throughout the clavicle. Geometric properties of percent bone area, polar second moment of area, and shape (Imax /Imin ) confirmed the conclusions drawn by existing research on clavicle macrostructure. Our results highlight that mediolateral shape changes might be accompanied by slight changes in Haversian density, but bone matrix organization is predominantly adapted to resisting tensile strains or torsion throughout and may be a major factor in the risk of fracture when experiencing atypical compression.
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Affiliation(s)
- Matthew A Crane
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Kyle M Kato
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Biren A Patel
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.,Human and Evolutionary Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Adam K Huttenlocker
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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19
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Marchi D, Harper C, Chirchir H, Ruff C. Relative fibular strength and locomotor behavior in KNM-WT 15000 and OH 35. J Hum Evol 2019; 131:48-60. [DOI: 10.1016/j.jhevol.2019.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/01/2019] [Accepted: 02/21/2019] [Indexed: 12/14/2022]
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20
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Pallas L, Daver G, Mackaye HT, Likius A, Vignaud P, Guy F. A window into the early evolutionary history of Cercopithecidae: Late Miocene evidence from Chad, Central Africa. J Hum Evol 2019; 132:61-79. [PMID: 31203852 DOI: 10.1016/j.jhevol.2019.03.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 03/11/2019] [Accepted: 03/13/2019] [Indexed: 10/26/2022]
Abstract
Central Africa is known as a major center of diversification for extant Old World Monkeys (OWM) and yet has a poorly documented fossil record of monkeys. Here we report a new colobine monkey (Cercopithecoides bruneti sp. nov.) from the Central African hominin-bearing fossiliferous area of Toros-Menalla, Chad at ca. 7 Ma. In addition to filling a gap in the spatial and temporal record of early OWM evolutionary history, we assess the ecomorphological diversity of early OWM by providing evidence on the onset of a folivorous diet and a partial reacquisition of terrestrial locomotor habits among Miocene colobines. We also support the phylogenetic affinities of the genus Cercopithecoides among the stem group of the extant African colobine monkeys.
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Affiliation(s)
- Laurent Pallas
- PALEVOPRIM: Laboratoire de Paléontologie, Evolution, Paléoécosystèmes et Paléoprimatologie, CNRS UMR 7262, Université de Poitiers, 86022 Poitiers cedex, France
| | - Guillaume Daver
- PALEVOPRIM: Laboratoire de Paléontologie, Evolution, Paléoécosystèmes et Paléoprimatologie, CNRS UMR 7262, Université de Poitiers, 86022 Poitiers cedex, France
| | - Hassane T Mackaye
- Département de Paléontologie, Université de N'Djamena, BP 1117, N'Djamena, Chad
| | - Andossa Likius
- Département de Paléontologie, Université de N'Djamena, BP 1117, N'Djamena, Chad
| | - Patrick Vignaud
- PALEVOPRIM: Laboratoire de Paléontologie, Evolution, Paléoécosystèmes et Paléoprimatologie, CNRS UMR 7262, Université de Poitiers, 86022 Poitiers cedex, France
| | - Franck Guy
- PALEVOPRIM: Laboratoire de Paléontologie, Evolution, Paléoécosystèmes et Paléoprimatologie, CNRS UMR 7262, Université de Poitiers, 86022 Poitiers cedex, France.
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21
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Lewton KL, Ritzman T, Copes LE, Garland T, Capellini TD. Exercise‐induced loading increases ilium cortical area in a selectively bred mouse model. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 168:543-551. [DOI: 10.1002/ajpa.23770] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/10/2018] [Accepted: 12/13/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Kristi L. Lewton
- Department of Integrative Anatomical Sciences Keck School of Medicine, University of Southern California, Los Angeles, CA
- Department of Biological Sciences Human & Evolutionary Biology Section, University of Southern California, Los Angeles, CA
- Department of Human Evolutionary Biology Harvard University, Cambridge, MA
| | - Terrence Ritzman
- Department of Neuroscience Washington University School of Medicine, St. Louis, MO
- Department of Anthropology Washington University St. Louis, MO
- Human Evolution Research Institute University of Cape Town, Cape Town, South Africa
| | - Lynn E. Copes
- Department of Medical Sciences, Frank H. Netter MD School of Medicine Quinnipiac University, Hamden, CT
| | - Theodore Garland
- Department of Evolution, Ecology, and Organismal Biology University of California Riverside, Riverside, CA
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22
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Lague MR, Chirchir H, Green DJ, Mbua E, Harris JWK, Braun DR, Griffin NL, Richmond BG. Cross-sectional properties of the humeral diaphysis of Paranthropus boisei: Implications for upper limb function. J Hum Evol 2018; 126:51-70. [PMID: 30583844 DOI: 10.1016/j.jhevol.2018.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 04/24/2018] [Accepted: 05/02/2018] [Indexed: 12/14/2022]
Abstract
A ∼1.52 Ma adult upper limb skeleton of Paranthropus boisei (KNM-ER 47000) recovered from the Koobi Fora Formation, Kenya (FwJj14E, Area 1A) includes most of the distal half of a right humerus (designated KNM-ER 47000B). Natural transverse fractures through the diaphysis of KNM-ER 470000B provide unobstructed views of cortical bone at two sections typically used for analyzing cross-sectional properties of hominids (i.e., 35% and 50% of humerus length from the distal end). Here we assess cross-sectional properties of KNM-ER 47000B and two other P. boisei humeri (OH 80-10, KNM-ER 739). Cross-sectional properties for P. boisei associated with bending/torsional strength (section moduli) and relative cortical thickness (%CA; percent cortical area) are compared to those reported for nonhuman hominids, AL 288-1 (Australopithecus afarensis), and multiple species of fossil and modern Homo. Polar section moduli (Zp) are assessed relative to a mechanically relevant measure of body size (i.e., the product of mass [M] and humerus length [HL]). At both diaphyseal sections, P. boisei exhibits %CA that is high among extant hominids (both human and nonhuman) and similar to that observed among specimens of Pleistocene Homo. High values for Zp relative to size (M × HL) indicate that P. boisei had humeral bending strength greater than that of modern humans and Neanderthals and similar to that of great apes, A. afarensis, and Homo habilis. Such high humeral strength is consistent with other skeletal features of P. boisei (reviewed here) that suggest routine use of powerful upper limbs for arboreal climbing.
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Affiliation(s)
- Michael R Lague
- School of Natural Sciences and Mathematics, Stockton University, 101 Vera King Farris Drive, Galloway, NJ 08205, USA.
| | - Habiba Chirchir
- Department of Biological Sciences, Marshall University, USA; Human Origins Program, National Museum of Natural History, Smithsonian Institution, USA
| | - David J Green
- Department of Anatomy, Campbell University School of Osteopathic Medicine, USA; Department of Anatomy, Midwestern University, USA
| | - Emma Mbua
- Department of Biological Sciences, Mount Kenya University, Kenya
| | | | - David R Braun
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, USA; Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Germany
| | - Nicole L Griffin
- Department of Anatomy and Cell Biology, Lewis Katz School of Medicine, Temple University, USA
| | - Brian G Richmond
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Germany; Division of Anthropology, American Museum of Natural History, USA
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23
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Granatosky MC, Karantanis NE, Rychlik L, Youlatos D. A suspensory way of life: Integrating locomotion, postures, limb movements, and forces in two-toed sloths Choloepus didactylus (Megalonychidae, Folivora, Pilosa). JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:570-588. [PMID: 30129260 DOI: 10.1002/jez.2221] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 06/25/2018] [Accepted: 08/24/2018] [Indexed: 12/22/2022]
Abstract
Over the last decade, we have learned much about the anatomy, evolutionary history, and biomechanics of the extant sloths. However, most of this study has involved studying sloths in controlled conditions, and few studies have explored how these animals are behaving in a naturalistic setting. In this study, we integrate positional activities in naturalistic conditions with kinematic and kinetic observations collected on a simulated runway to best capture the biomechanical behavior of Linnaeus's two-toed sloths. We confirm that the dominant positional behaviors consist of hanging below the support using a combination of forelimbs and hindlimbs, and walking quadrupedally below the branches. The majority of these behaviors occur on horizontal substrates that are approximately 5-10 cm in diameter. The kinematics of suspensory walking observed both in the naturalistic settings and on simulated arboreal runways are dominated by movement of the proximal limb elements, while distal limb elements tend to show little excursion. Joint kinematics are similar between the naturalistic setting and the simulated runway, but movements of the shoulder and hip tend to be exaggerated while moving in simulated conditions. Kinetic patterns of the two-toed sloth can be explained almost entirely by considering them as an inverted linked strut. However, medially directed forces toward the substrate were more frequent than expected in the forelimb, which may help sloths maintain a better "grip" on the substrate. This study serves as a model of how to gain a comprehensive understanding of the functional-adaptive profile of a particular species.
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Affiliation(s)
- Michael C Granatosky
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois
| | - Nikolaos E Karantanis
- Princess Royal College of Animal Management and Saddlery, Capel Manor College, London, UK.,Department of Zoology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Leszek Rychlik
- Department of Systematic Zoology, Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Dionisios Youlatos
- Department of Zoology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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24
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Voeten DFAE, Cubo J, de Margerie E, Röper M, Beyrand V, Bureš S, Tafforeau P, Sanchez S. Wing bone geometry reveals active flight in Archaeopteryx. Nat Commun 2018. [PMID: 29535376 PMCID: PMC5849612 DOI: 10.1038/s41467-018-03296-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Archaeopteryx is an iconic fossil taxon with feathered wings from the Late Jurassic of Germany that occupies a crucial position for understanding the early evolution of avian flight. After over 150 years of study, its mosaic anatomy unifying characters of both non-flying dinosaurs and flying birds has remained challenging to interpret in a locomotory context. Here, we compare new data from three Archaeopteryx specimens obtained through phase-contrast synchrotron microtomography to a representative sample of archosaurs employing a diverse array of locomotory strategies. Our analyses reveal that the architecture of Archaeopteryx's wing bones consistently exhibits a combination of cross-sectional geometric properties uniquely shared with volant birds, particularly those occasionally utilising short-distance flapping. We therefore interpret that Archaeopteryx actively employed wing flapping to take to the air through a more anterodorsally posteroventrally oriented flight stroke than used by modern birds. This unexpected outcome implies that avian powered flight must have originated before the latest Jurassic.
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Affiliation(s)
- Dennis F A E Voeten
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS-40220, 38043, Grenoble Cedex, France. .,Department of Zoology and Laboratory of Ornithology, Palacký University, 17. listopadu 50, 771 46, Olomouc, Czech Republic.
| | - Jorge Cubo
- Sorbonne Université, CNRS-INSU, Institut des Sciences de la Terre Paris, ISTeP UMR 7193, F-75005, Paris, France
| | - Emmanuel de Margerie
- CNRS, Laboratoire d'éthologie animale et humaine, Université de Rennes 1, Université de Caen Normandie, 263 Avenue du Général Leclerc, 35042, Rennes, France
| | - Martin Röper
- Bürgermeister-Müller-Museum, Bahnhofstrasse 8, 91807, Solnhofen, Germany.,Bayerische Staatssammlung für Paläontologie und Geologie, Richard-Wagner-Str. 10, D-80333, München, Germany
| | - Vincent Beyrand
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS-40220, 38043, Grenoble Cedex, France.,Department of Zoology and Laboratory of Ornithology, Palacký University, 17. listopadu 50, 771 46, Olomouc, Czech Republic
| | - Stanislav Bureš
- Department of Zoology and Laboratory of Ornithology, Palacký University, 17. listopadu 50, 771 46, Olomouc, Czech Republic
| | - Paul Tafforeau
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS-40220, 38043, Grenoble Cedex, France
| | - Sophie Sanchez
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, CS-40220, 38043, Grenoble Cedex, France.,Science for Life Laboratory and Uppsala University, Subdepartment of Evolution and Development, Department of Organismal Biology, Evolutionary Biology Centre, Norbyvägen 18A, 752 36, Uppsala, Sweden
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25
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Patel BA, Organ JM, Jashashvili T, Bui SH, Dunsworth HM. Ontogeny of hallucal metatarsal rigidity and shape in the rhesus monkey (Macaca mulatta) and chimpanzee (Pan troglodytes). J Anat 2018; 232:39-53. [PMID: 29098692 PMCID: PMC5735049 DOI: 10.1111/joa.12720] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2017] [Indexed: 11/28/2022] Open
Abstract
Life history variables including the timing of locomotor independence, along with changes in preferred locomotor behaviors and substrate use during development, influence how primates use their feet throughout ontogeny. Changes in foot function during development, in particular the nature of how the hallux is used in grasping, can lead to different structural changes in foot bones. To test this hypothesis, metatarsal midshaft rigidity [estimated from the polar second moment of area (J) scaled to bone length] and cross-sectional shape (calculated from the ratio of maximum and minimum second moments of area, Imax /Imin ) were examined in a cross-sectional ontogenetic sample of rhesus macaques (Macaca mulatta; n = 73) and common chimpanzees (Pan troglodytes; n = 79). Results show the hallucal metatarsal (Mt1) is relatively more rigid (with higher scaled J-values) in younger chimpanzees and macaques, with significant decreases in relative rigidity in both taxa until the age of achieving locomotor independence. Within each age group, Mt1 rigidity is always significantly higher in chimpanzees than macaques. When compared with the lateral metatarsals (Mt2-5), the Mt1 is relatively more rigid in both taxa and across all ages; however, this difference is significantly greater in chimpanzees. Length and J scale with negative allometry in all metatarsals and in both species (except the Mt2 of chimpanzees, which scales with positive allometry). Only in macaques does Mt1 midshaft shape significantly change across ontogeny, with older individuals having more elliptical cross-sections. Different patterns of development in metatarsal diaphyseal rigidity and shape likely reflect the different ways in which the foot, and in particular the hallux, functions across ontogeny in apes and monkeys.
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Affiliation(s)
- Biren A. Patel
- Department of Integrative Anatomical SciencesKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
- Human and Evolutionary Biology SectionDepartment of Biological SciencesUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Jason M. Organ
- Department of Anatomy and Cell BiologyIndiana University School of MedicineIndianapolisINUSA
- Department of Biomedical EngineeringIndiana University – Purdue University IndianapolisIndianapolisINUSA
| | - Tea Jashashvili
- Molecular Imaging CenterDepartment of RadiologyKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
- Department of Geology and PaleontologyGeorgian National MuseumTbilisiGeorgia
| | - Stephanie H. Bui
- Human and Evolutionary Biology SectionDepartment of Biological SciencesUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Holly M. Dunsworth
- Department of Sociology and AnthropologyUniversity of Rhode IslandKingstonRIUSA
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26
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The Postcranial Musculoskeletal System of Xenarthrans: Insights from over Two Centuries of Research and Future Directions. J MAMM EVOL 2017. [DOI: 10.1007/s10914-017-9408-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Sylvester AD, Terhune CE. Trabecular mapping: Leveraging geometric morphometrics for analyses of trabecular structure. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 163:553-569. [PMID: 28432829 DOI: 10.1002/ajpa.23231] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 04/04/2017] [Accepted: 04/04/2017] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Trabecular microstructure of limb bone epiphyses has been used to elucidate the relationship between skeletal form and behavior among mammals. Such studies have often relied on the analysis of a single volume of interest (VOI). Here we present a method for evaluating variation in bone microstructure across articular surfaces by leveraging sliding semilandmarks. METHODS Two samples were used to demonstrate the proposed methodology and test the hypothesis that microstructural variables are homogeneously distributed: tali from two ape genera (Pan and Pongo, n = 9) and modern human distal femora (n = 10). Sliding semilandmarks were distributed across articular surfaces and used to locate the position of multiple VOIs immediately deep to the cortical shell. Trabecular bone properties were quantified using the BoneJ plugin for ImageJ. Nonparametric MANOVA tests were used to make group comparisons and differences were explored using principal components analysis and visualized using color maps. RESULTS Tests reveal that trabecular parameters are not distributed homogeneously and identify differences between chimpanzee and orangutan tali with regards to trabecular spacing and degree of anisotropy, with chimpanzee tali being more anisotropic and having more uniformly spaced trabeculae. Human males and females differed in the pattern of trabecular spacing with males having more uniform trabecular spacing across the joint surface. CONCLUSIONS The proposed procedure quantifies variation in trabecular bone parameters across joint surfaces and allows for meaningful statistical comparisons between groups of interest. Consequently it holds promise to help elucidate links between trabecular bone structure and animal behavior.
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Affiliation(s)
- Adam D Sylvester
- Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Claire E Terhune
- Department of Anthropology, University of Arkansas, Fayetteville, Arkansas
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Granatosky MC, Schmitt D. Forelimb and hind limb loading patterns during below branch quadrupedal locomotion in the two‐toed sloth. J Zool (1987) 2017. [DOI: 10.1111/jzo.12455] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- M. C. Granatosky
- Department of Organismal Biology and Anatomy University of Chicago Chicago IL USA
| | - D. Schmitt
- Department of Evolutionary Anthropology Duke University Durham NC USA
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Marchi D, Ruff CB, Capobianco A, Rafferty KL, Habib MB, Patel BA. The locomotion ofBabakotia radofilaiinferred from epiphyseal and diaphyseal morphology of the humerus and femur. J Morphol 2016; 277:1199-218. [DOI: 10.1002/jmor.20569] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 04/06/2016] [Accepted: 05/27/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Damiano Marchi
- Department of Biology; University of Pisa; Pisa 56126 Italy
- Evolutionary Studies Institute, University of the Witwatersrand; Johannesburg WITS 2050 South Africa
| | - Christopher B. Ruff
- Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine; Baltimore Maryland 21111
| | - Alessio Capobianco
- Department of Biology; University of Pisa; Pisa 56126 Italy
- Scuola Normale Superiore; Pisa 56126 Italy
| | - Katherine L. Rafferty
- Department of Orthodontics School of Dentistry; University of Washington; Seattle Washington 98195
| | - Michael B. Habib
- Department of Cell and Neurobiology Keck School of Medicine; University of Southern California; Los Angeles California 90033
| | - Biren A. Patel
- Evolutionary Studies Institute, University of the Witwatersrand; Johannesburg WITS 2050 South Africa
- Department of Cell and Neurobiology Keck School of Medicine; University of Southern California; Los Angeles California 90033
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Burgess ML, Schmitt D, Zeininger A, McFarlin SC, Zihlman AL, Polk JD, Ruff CB. Ontogenetic scaling of fore limb and hind limb joint posture and limb bone cross-sectional geometry in vervets and baboons. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 161:72-83. [DOI: 10.1002/ajpa.23009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 12/26/2022]
Affiliation(s)
- M. Loring Burgess
- Center for Functional Anatomy and Evolution; Johns Hopkins University School of Medicine; Baltimore MD
| | - Daniel Schmitt
- Department of Evolutionary Anthropology; Duke University; Durham NC
| | - Angel Zeininger
- Department of Evolutionary Anthropology; Duke University; Durham NC
| | - Shannon C. McFarlin
- Department of Anthropology; Center for the Advanced Study of Human Paleobiology, the George Washington University; Washington DC
| | | | - John D. Polk
- Department of Anthropology; University of Illinois at Urbana-Champaign; Urbana IL
| | - Christopher B. Ruff
- Center for Functional Anatomy and Evolution; Johns Hopkins University School of Medicine; Baltimore MD
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Sarringhaus LA, MacLatchy LM, Mitani JC. Long bone cross-sectional properties reflect changes in locomotor behavior in developing chimpanzees. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 160:16-29. [PMID: 26780478 DOI: 10.1002/ajpa.22930] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 12/08/2015] [Accepted: 12/10/2015] [Indexed: 11/07/2022]
Abstract
OBJECTIVES Recent studies indicate that the locomotor behavior of wild chimpanzees changes during development. Before transitioning to quadrupedal knuckle-walking in adulthood, young chimpanzees engage in a significant amount of upper limb loading suspensory behavior. We investigated whether these dramatic changes in locomotion influence the strength and shape of chimpanzee long bones. MATERIALS AND METHODS We examined changes in chimpanzee arboreal locomotion over the course of development using behavioral data collected on wild chimpanzees. We measured the midshaft geometric properties of femora and humeri of wild-caught individuals housed in museum collections using micro computed tomographic scans. RESULTS Chimpanzees spent less time moving arboreally as they aged. Femoral/humeral strength ratios also increased with age, as predicted by the changing loading environment during development. Additional analyses revealed that femoral shape, but not humeral shape, varied across chimpanzee age classes. Adult femora were more elliptical compared with those of infants. This change in adult femora is consistent with the observation that adult chimpanzees spend most of their time moving terrestrially and consequently experience a less variable loading environment than do infants. DISCUSSION Taken together, these findings contribute to our understanding of how ontogenetic changes in function affect form. As similar changes may have characterized the behavioral and skeletal ontogeny of extinct hominoids including hominins, these findings furnish a potential means to make inferences about the behavior of fossil taxa based on the structural properties of their bones.
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Affiliation(s)
- Lauren A Sarringhaus
- Evolutionary Studies Institute, Palaeosciences Centre, University of the Witwatersrand, Johannesburg, South Africa.,University of Maryland University College Europe, PE28 4DE, England
| | - Laura M MacLatchy
- Department of Anthropology, University of Michigan, Ann Arbor, MI, 48109
| | - John C Mitani
- Department of Anthropology, University of Michigan, Ann Arbor, MI, 48109
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Nadell JA, Shaw CN. Phenotypic plasticity and constraint along the upper and lower limb diaphyses ofHomo sapiens. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2015; 159:410-22. [DOI: 10.1002/ajpa.22889] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/16/2015] [Accepted: 10/18/2015] [Indexed: 11/10/2022]
Affiliation(s)
| | - Colin N. Shaw
- Department of Archaeology and Anthropology; University of Cambridge; Cambridge UK
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Almécija S, Orr CM, Tocheri MW, Patel BA, Jungers WL. Exploring Phylogenetic and Functional Signals in Complex Morphologies: The Hamate of Extant Anthropoids as a Test-Case Study. Anat Rec (Hoboken) 2014; 298:212-29. [DOI: 10.1002/ar.23079] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 10/11/2014] [Indexed: 11/05/2022]
Affiliation(s)
- Sergio Almécija
- Department of Anatomical Sciences; Stony Brook University School of Medicine; Stony Brook New York
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona; Edifici Z (ICTA-ICP), campus de la UAB, c/ de les Columnes, s/n., 08193 Cerdanyola del Vallès Barcelona Spain
- NYCEP Morphometrics Group
| | - Caley M. Orr
- Department of Anatomy; Midwestern University; Downers Grove Illinois
| | - Matthew W. Tocheri
- Human Origins Program, Department of Anthropology; National Museum of Natural History, Smithsonian Institution; 10th and Constitution Avenue NW Washington DC
- Department of Anthropology; Center for the Advanced Study of Hominid Paleobiology, The George Washington University; Washington DC
| | - Biren A. Patel
- Cell and Neurobiology; Keck School of Medicine, University of Southern California; Los Angeles California
- Human and Evolutionary Biology Section; Department of Biological Sciences, University of Southern California; Los Angeles California
| | - William L. Jungers
- Department of Anatomical Sciences; Stony Brook University School of Medicine; Stony Brook New York
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Milella M. The influence of life history and sexual dimorphism on entheseal changes in modern humans and African great apes. PLoS One 2014; 9:e107963. [PMID: 25251439 PMCID: PMC4175998 DOI: 10.1371/journal.pone.0107963] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 08/16/2014] [Indexed: 11/19/2022] Open
Abstract
Entheseal changes have been widely studied with regard to their correlation to biomechanical stress and their usefulness for biocultural reconstructions. However, anthropological and medical studies have demonstrated the marked influence of both age and sex on the development of these features. Studies of entheseal changes are mostly aimed in testing functional hypotheses and are mostly focused on modern humans, with few data available for non-human primates. The lack of comparative studies on the effect of age and sex on entheseal changes represent a gap in our understanding of the evolutionary basis of both development and degeneration of the human musculoskeletal system. The aim of the present work is to compare age trajectories and patterns of sexual dimorphism in entheseal changes between modern humans and African great apes. To this end we analyzed 23 postcranial entheses in a human contemporary identified skeletal collection (N = 484) and compared the results with those obtained from the analysis of Pan (N = 50) and Gorilla (N = 47) skeletal specimens. Results highlight taxon-specific age trajectories possibly linked to differences in life history schedules and phyletic relationships. Robusticity trajectories separate Pan and modern humans from Gorilla, whereas enthesopathic patterns are unique in modern humans and possibly linked to their extended potential lifespan. Comparisons between sexes evidence a decreasing dimorphism in robusticity from Gorilla, to modern humans to Pan, which is likely linked to the role played by size, lifespan and physical activity on robusticity development. The present study confirms previous hypotheses on the possible relevance of EC in the study of life history, pointing moreover to their usefulness in evolutionary studies.
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Affiliation(s)
- Marco Milella
- Anthropological Institute and Museum, University of Zurich, Zurich, Switzerland
- * E-mail:
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