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Dunmore CJ, Bachmann S, Synek A, Pahr DH, Skinner MM, Kivell TL. The deep trabecular structure of first metacarpals in extant hominids. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2024; 183:e24695. [PMID: 36790736 DOI: 10.1002/ajpa.24695] [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: 07/07/2022] [Revised: 11/07/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
OBJECTIVES Recent studies have associated subarticular trabecular bone distribution in the extant hominid first metacarpal (Mc1) with observed thumb use, to infer fossil hominin thumb use. Here, we analyze the entire Mc1 to test for interspecific differences in: (1) the absolute volume of trabecular volume fraction, (2) the distribution of the deeper trabecular network, and (3) the distribution of trabeculae in the medullary cavity, especially beneath the Mc1 disto-radial flange. MATERIALS AND METHODS Trabecular bone was imaged using micro-computed tomography in a sample of Homo sapiens (n = 11), Pan paniscus (n = 10), Pan troglodytes (n = 11), Gorilla gorilla (n = 10) and Pongo sp., (n = 7). Using Canonical Holistic Morphometric Analysis (cHMA), we tested for interspecific differences in the trabecular bone volume fraction (BV/TV) and its relative distribution (rBV/TV) throughout the Mc1, including within the head, medullary cavity, and base. RESULTS P. paniscus had the highest, and H. sapiens the lowest, BV/TV relative to other species. rBV/TV distribution statistically distinguished the radial concentrations and lack of medullary trabecular bone in the H. sapiens Mc1 from all other hominids. H. sapiens and, to a lesser extent, G. gorilla also had a significantly higher trabecular volume beneath the disto-radial flange relative to other hominids. DISCUSSION These results are consistent with differences in observed thumb use in these species and may also reflect systemic differences in bone volume fraction. The trabecular bone extension into the medullary cavity and concentrations beneath the disto-radial flange may represent crucial biomechanical signals that will aid in the inference of fossil hominin thumb use.
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Affiliation(s)
- Christopher J Dunmore
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK
| | - Sebastian Bachmann
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, Vienna, Austria
| | - Alexander Synek
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, Vienna, Austria
| | - Dieter H Pahr
- Institute of Lightweight Design and Structural Biomechanics, TU Wien, Vienna, Austria
- Department of Anatomy and Biomechanics, Division Biomechanics, Karl Landsteiner University of Health Sciences, Krems, Austria
| | - Matthew M Skinner
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa
| | - Tracy L Kivell
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa
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Young MW, McKamy AJ, Dickinson E, Yarbro J, Ragupathi A, Guru N, Avey-Arroyo JA, Butcher MT, Granatosky MC. Three toes and three modes: Dynamics of terrestrial, suspensory, and vertical locomotion in brown-throated three-toed sloths (Bradypodidae, Xenarthra). JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:383-397. [PMID: 36747379 DOI: 10.1002/jez.2684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 02/08/2023]
Abstract
Living sloths exhibit numerous anatomical specializations towards inverted quadrupedalism, however, previous studies have noted a more varied locomotor repertoire than previously anticipated. In this study, we present spatiotemporal gait characteristics and triaxial kinetic data from the brown-throated three-toed sloth (Bradypus variegatus) across three locomotor modes: terrestrial quadrupedal "crawling", suspensory walking, and vertical climbing. Compared to quadrupedal crawling and suspensory walking, B. variegatus adopted longer contact times and stride durations, larger duty factors, and greater speed during vertical climbing. Net fore-aft impulses were significantly greater during vertical climbing in both limb pairs than in quadrupedal crawling and suspensory walking. Functionally, during quadrupedal crawling and vertical climbing, both limb pairs served propulsive roles, while differentiation between a propulsive forelimb and braking hindlimb was observed during suspension. Net tangential forces differentiated vertical climbing kinetics from the other modes of locomotion, with the introduction of bidirectional pulling and pushing forces in the forelimb and hindlimb, respectively. The net mediolateral impulses were similar in vertical climbing and quadrupedal crawling as both limb pairs directed forces in one direction, whereas during suspensory walking, the laterally dominant forelimb was opposed by the medially dominant hindlimb. In total, this study provides novel data on the diverse locomotor dynamics in a slow-moving arboreal tetrapod and posits new testable hypotheses about the neuroplasticity and ease of transitioning between locomotor behaviors. The strikingly similar kinetic profiles of quadrupedal crawling and suspensory walking compared to vertical climbing suggest shared neuromuscular and mechanical demands between these mirrored locomotor modes.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Andrew J McKamy
- Department of Biological Sciences, Youngstown State University, Youngstown, Ohio, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Johnathan Yarbro
- New York Institute of Technology College of Osteopathic Medicine, Jonesboro, Arkansas, USA
| | - Ashwin Ragupathi
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Navjot Guru
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | | | - Michael T Butcher
- Department of Biological Sciences, Youngstown State University, Youngstown, Ohio, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA.,Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
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3
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Mossor AM, Young JW, Butcher MT. Does a suspensory lifestyle result in increased tensile strength?: Organ level material properties of sloth limb bones. J Exp Biol 2022; 225:274333. [PMID: 35142360 DOI: 10.1242/jeb.242866] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 02/07/2022] [Indexed: 11/20/2022]
Abstract
The material composition of vertebrate connective tissue is highly conserved across taxa. Existing data suggest that the compressive and tensile strength of limb bones are very similar despite marked variation in limb posture and locomotor patterns. However, the material properties of limb bone tissue from suspensory taxa have not been formally evaluated. Sloths are nearly obligatory in their use of below-branch suspensory locomotion and posture, thus placing their limb bones and associated soft tissue structures under routine tensile loading. It is possible that sloth limb bones are modified for enhanced tensile strength, perhaps at the expense of compressive strength. Fore- and hindlimb bones of two-toed (Choloepus hoffmanni) and three-toed (Bradypus variegatus) sloths were tested in compression and bending to evaluate this hypothesis. Strength and elastic (Young's) modulus were similarly lower in sloth limb bones during both compression and bending, as compared to pronograde taxa. Ratios of peak bending strength to compressive strength additionally were elevated (sloths: 1.4-1.7; upright taxa: 0.6-1.2) for sloth limb bones. Overall, the material properties measured from the limb bones of tree sloths support our hypothesis of predicted function in a tensile limb system. Future studies should aim to directly test bones in tension to confirm indications of elevated axial tensile strength. Nevertheless, the results herein expand understanding of functional adaptation in mammalian tissue for a range of locomotor/postural behaviors that were previously unexplored.
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Affiliation(s)
- A M Mossor
- Department of Biological Sciences, Youngstown State University, Youngstown OH 44555, USA.,Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown OH, USA
| | - J W Young
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown OH, USA
| | - M T Butcher
- Department of Biological Sciences, Youngstown State University, Youngstown OH 44555, USA
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Houssaye A, de Perthuis A, Houée G. Sesamoid bones also show functional adaptation in their microanatomy-The example of the patella in Perissodactyla. J Anat 2022; 240:50-65. [PMID: 34402049 PMCID: PMC8655183 DOI: 10.1111/joa.13530] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 07/21/2021] [Accepted: 07/21/2021] [Indexed: 11/27/2022] Open
Abstract
The patella is the largest sesamoid bone of the skeleton. It is strongly involved in the knee, improving output force and velocity of the knee extensors, and thus plays a major role in locomotion and limb stability. However, the relationships between its structure and functional constraints, that would enable a better understanding of limb bone functional adaptations, are poorly known. This contribution proposes a comparative analysis, both qualitative and quantitative, of the microanatomy of the whole patella in perissodactyls, which show a wide range of morphologies, masses, and locomotor abilities, in order to investigate how the microanatomy of the patella adapts to evolutionary constraints. The inner structure of the patella consists of a spongiosa surrounded by a compact cortex. Contrary to our expectations, there is no increase in compactness with bone size, and thus body size and weight, but only an increase in the tightness of the spongiosa. No particular thickening of the cortex associated with muscle insertions is noticed but a strong thickening is observed anteriorly at about mid-length, where the strong intermediate patellar ligament inserts. The trabeculae are mainly oriented perpendicularly to the posterior articular surface, which highlights that the main stress is anteroposteriorly directed, maintaining the patella against the femoral trochlea. Conversely, anteriorly, trabeculae are rather circumferentially oriented, following the insertion of the patellar ligament and, possibly also, of the quadriceps tendon. A strong variation is observed among perissodactyl families but also intraspecifically, which is in accordance with previous studies suggesting a higher variability in sesamoid bones. Clear trends are nevertheless observed between the three families. Equids have a much thinner cortex than ceratomorphs. Rhinos and equids, both characterized by a development of the medial border, show an increase in trabecular density laterally suggesting stronger stresses laterally. The inner structure in tapirs is more homogeneous despite the absence of medial development of the medial border with no "compensation" of the inner structure, which suggests different stresses on their knees associated with a different morphology of their patellofemoral joint.
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Affiliation(s)
- Alexandra Houssaye
- Département Adaptations du vivantUMR 7179 CNRS/Muséum National d'Histoire NaturelleParisFrance
| | - Adrien de Perthuis
- Département Adaptations du vivantUMR 7179 CNRS/Muséum National d'Histoire NaturelleParisFrance
| | - Guillaume Houée
- Département Adaptations du vivantUMR 7179 CNRS/Muséum National d'Histoire NaturelleParisFrance
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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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Gavazzi LM, Kjosness KM, Reno PL. Ossification pattern of the unusual pisiform in two-toed (Choloepus) and three-toed sloths (Bradypus). Anat Rec (Hoboken) 2021; 305:1804-1819. [PMID: 34779120 DOI: 10.1002/ar.24832] [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: 09/02/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 11/06/2022]
Abstract
Two-toed (Choloepus sp.) and three-toed (Bradypus sp.) sloths possess short, rounded pisiforms that are rare among mammals and differ from other members of Xenarthra like the giant anteater (Myrmecophaga tridactyla) which retain elongated, rod-like pisiforms in common with most mammals. Using photographs, radiographs, and μCT, we assessed ossification patterns in the pisiform and the paralogous tarsal, the calcaneus, for two-toed sloths, three-toed sloths, and giant anteaters to determine the process by which pisiform reduction occurs in sloths and compare it to other previously studied examples of pisiform reduction in humans and orangutans. Both extant sloth genera achieve pisiform reduction through the loss of a secondary ossification center and the likely disruption of the associated growth plate based on an unusually porous subchondral surface. This represents a third unique mechanism of pisiform reduction among mammals, along with primary ossification center loss in humans and retention of two ossification centers with likely reduced growth periods in orangutans. Given the remarkable similarities between two-toed and three-toed sloth pisiform ossification patterns and the presence of pisiform reduction in fossil sloths, extant sloth pisiform morphology does not appear to represent a recent convergent adaptation to suspensory locomotion, but instead is likely to be an ancestral trait of Folivora that emerged early in the radiation of extant and fossil sloths.
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Affiliation(s)
- Lia M Gavazzi
- School of Biomedical Sciences, Kent State University, Kent, Ohio, USA.,Musculoskeletal Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, USA
| | - Kelsey M Kjosness
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, Pennsylvania, USA
| | - Philip L Reno
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, Pennsylvania, USA
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7
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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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8
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Houssaye A, Martin F, Boisserie JR, Lihoreau F. Paleoecological Inferences from Long Bone Microanatomical Specializations in Hippopotamoidea (Mammalia, Artiodactyla). J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09536-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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9
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Spear JK, Williams SA. Mosaic patterns of homoplasy accompany the parallel evolution of suspensory adaptations in the forelimb of tree sloths (Folivora: Xenarthra). Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlaa154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Abstract
We examine how derived functional signal and phylogenetic inheritance interact in the forelimb of tree sloths, to understand the relative contribution of each in the evolution of a novel morphobehavioural suite. Molecular and craniodental data demonstrate that extant tree sloths evolved suspensory behaviours and associated morphologies from a non-suspensory ancestor independently of one another, making them a useful model system. We find that convergence in univariate traits is expressed mosaically, although the signal is largely functional. Three-dimensional analyses suggest there is greater conservatism of gross morphology in more proximal bones than in more distal elements. Convergence in some univariate scapular traits is independent of the gross morphology of the scapula itself, demonstrating that functionally relevant morphologies were mapped on to a more conserved scapular shape. Our results suggest that morphological homoplasy is expressed in a mosaic manner. The relationship between homoplasy and trait integration may be more nuanced than previously thought, even within a single adaptive system.
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Affiliation(s)
- Jeffrey K Spear
- Center for the Study of Human Origins & Department of Anthropology, New York University, New York, USA
- New York Consortium in Evolutionary Primatology, New York, USA
| | - Scott A Williams
- Center for the Study of Human Origins & Department of Anthropology, New York University, New York, USA
- New York Consortium in Evolutionary Primatology, New York, USA
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10
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Alfieri F, Nyakatura JA, Amson E. Evolution of bone cortical compactness in slow arboreal mammals. Evolution 2020; 75:542-554. [PMID: 33314086 DOI: 10.1111/evo.14137] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/16/2020] [Accepted: 11/22/2020] [Indexed: 01/26/2023]
Abstract
Convergent evolution is a major topic in evolutionary biology. Low bone cortical compactness (CC, a measure of porosity of cortical bone) in the extant genera of "tree sloths," has been linked to their convergent slow arboreal ecology. This proposed relationship of low CC with a slow arboreal lifestyle suggests potential convergent evolution of this trait in other slow arboreal mammals. Femoral and humeral CC were analyzed in "tree sloths," lorisids, koala, and extinct palaeopropithecids and Megaladapis, in comparison to closely related but ecologically distinct taxa, in a phylogenetic framework. Low CC in "tree sloths" is unparalleled by any analyzed clade and the high CC in extinct sloths suggests the recent convergence of low CC in "tree sloths." A tendency for low CC was found in Palaeopropithecus and Megaladapis. However, lorisids and the koala yielded unexpected CC patterns, preventing the recognition of a straightforward convergence of low CC in slow arboreal mammals. This study uncovers a complex relationship between CC and convergent evolution of slow arboreality, highlighting the multifactorial specificity of bone microstructure.
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Affiliation(s)
- Fabio Alfieri
- Institut für Biologie, Humboldt Universität zu Berlin, Berlin, Germany.,Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Berlin, Germany
| | - John A Nyakatura
- Institut für Biologie, Humboldt Universität zu Berlin, Berlin, Germany
| | - Eli Amson
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Berlin, Germany
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Wölfer J, Nyakatura JA. Weighing homoplasy against alternative scenarios with the help of macroevolutionary modeling: A case study on limb bones of fossorial sciuromorph rodents. Ecol Evol 2019; 9:11025-11039. [PMID: 31641452 PMCID: PMC6802075 DOI: 10.1002/ece3.5592] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 07/30/2019] [Indexed: 11/29/2022] Open
Abstract
Homoplasy is a strong indicator of a phenotypic trait's adaptive significance when it can be linked to a similar function. We assessed homoplasy in functionally relevant scapular and femoral traits of Marmotini and Xerini, two sciuromorph rodent clades that independently acquired a fossorial lifestyle from an arboreal ancestor. We studied 125 species in the scapular dataset and 123 species in the femoral dataset. Pairwise evolutionary model comparison was used to evaluate whether homoplasy of trait optima is more likely than other plausible scenarios. The most likely trend of trait evolution among all traits was assessed via likelihood scoring of all considered models. The homoplasy hypothesis could never be confirmed as the single most likely model. Regarding likelihood scoring, scapular traits most frequently did not differ among Marmotini, Xerini, and arboreal species. For the majority of femoral traits, results indicate that Marmotini, but not Xerini, evolved away from the ancestral arboreal condition. We conclude on the basis of the scapular results that the forelimbs of fossorial and arboreal sciuromorphs share mostly similar functional demands, whereas the results on the femur indicate that the hind limb morphology is less constrained, perhaps depending on the specific fossorial habitat.
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Affiliation(s)
- Jan Wölfer
- AG Morphologie und FormengeschichteInstitut für BiologieHumboldt‐Universität zu BerlinBerlinGermany
- Bild Wissen Gestaltung, Ein Interdisziplinäres LaborHumboldt‐Universität zu BerlinBerlinGermany
| | - John A. Nyakatura
- AG Morphologie und FormengeschichteInstitut für BiologieHumboldt‐Universität zu BerlinBerlinGermany
- Bild Wissen Gestaltung, Ein Interdisziplinäres LaborHumboldt‐Universität zu BerlinBerlinGermany
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