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Galis F, Van Dooren TJM, van der Geer AAE. Breaking the constraint on the number of cervical vertebrae in mammals: On homeotic transformations in lorises and pottos. Evol Dev 2022; 24:196-210. [PMID: 36316803 PMCID: PMC9788262 DOI: 10.1111/ede.12424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 07/26/2022] [Accepted: 10/10/2022] [Indexed: 11/07/2022]
Abstract
Mammals almost always have seven cervical vertebrae. The strong evolutionary constraint on changes in this number has been broken in sloths and manatees. We have proposed that the extremely low activity and metabolic rates of these species relax the stabilizing selection against changes in the cervical count. Our hypothesis is that strong stabilizing selection in other mammals is largely indirect and due to associated pleiotropic effects, including juvenile cancers. Additional direct selection can occur due to biomechanical problems (thoracic outlet syndrome). Low metabolic and activity rates are thought to diminish these direct and indirect effects. To test this hypothesis within the primates, we have compared the number of cervical vertebrae of three lorisid species with particularly low activity and metabolic rates with those of more active primate species, including with their phylogenetically closest active relatives, the galagids (bushbabies). In support of our hypothesis, we found that 37.6% of the lorisid specimens had an abnormal cervical count, which is a higher percentage than in the other nine primate families, in which the incidence varied from zero to 2.2%. We conclude that our data support the importance of internal selection in constraining evolvability and of a relaxed stabilizing selection for increasing evolvability. Additionally, we discuss that there is no support for a role of the muscularized diaphragm in the evolutionary constraint.
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Affiliation(s)
- Frietson Galis
- Naturalis Biodiversity CenterLeidenThe Netherlands,Institute of BiologyLeiden UniversityLeidenThe Netherlands
| | - Tom J. M. Van Dooren
- Naturalis Biodiversity CenterLeidenThe Netherlands,CNRS, Institute of Ecology and Environmental Sciences iEES ParisSorbonne University ParisParisFrance
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2
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Vertebral anomalies in a natural population of Taricha granulosa (Caudata: Salamandridae). ZOOMORPHOLOGY 2022. [DOI: 10.1007/s00435-022-00559-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AbstractDevelopmental plasticity, a common pattern in lissamphibian evolution, results in numerous alternative morphologies among species and also within populations. In the present study, a natural population of the salamander Taricha granulosa (Salamandridae) was examined to detect variation in the vertebral count and to identify potential deformities of their vertebral column. The number of trunk vertebrae varied between 11 and 13 and we recorded 58 individuals with 69 anomalous vertebral elements. These anomalies range from congenital malformations (block vertebrae, unilateral bars, hemivertebrae), extra ossifications in the haemal region, to posttraumatic pathologies. Most osseous pathologies were encountered in the caudal region of the axial skeleton. Our data suggest a high frequency of vertebral malformations in salamanders; however, the identification of the exact causes remains challenging.
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3
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Krenn VA, Fornai C, Webb NM, Woodert MA, Prosch H, Haeusler M. The morphological consequences of segmentation anomalies in the human sacrum. AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY 2022; 177:690-707. [PMID: 36787761 PMCID: PMC9303760 DOI: 10.1002/ajpa.24466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 11/25/2021] [Accepted: 12/07/2021] [Indexed: 04/27/2023]
Abstract
OBJECTIVES Despite the high frequency of segmentation anomalies in the human sacrum, their evolutionary and clinical implications remain controversial. Specifically, inconsistencies involving the classification and counting methods obscure accurate assessment of lumbosacral transitional vertebrae. Therefore, we aim to establish more reliable morphological and morphometric methods for differentiating between sacralizations and lumbarizations in clinical and paleontological contexts. MATERIALS AND METHODS Using clinical CT data from 145 individuals aged 14-47 years, vertebral counts and the spatial relationship between the sacrum and adjoining bony structures were assessed, while the morphological variation of the sacrum was assessed using geometric morphometrics based on varied landmark configurations. RESULTS The prevalence of lumbosacral and sacrococcygeal segmentation anomalies was 40%. Lumbarizations and sacralizations were reliably distinguishable based on the spatial relationship between the iliac crest and the upward or downward trajectory of the linea terminalis on the sacrum. Different craniocaudal orientations of the alae relative to the corpus of the first sacral vertebra were also reflected in the geometric morphometric analyses. The fusion of the coccyx (32%) was frequently coupled with lumbarizations, suggesting that the six-element sacra more often incorporate the coccyx rather than the fifth lumbar vertebra. CONCLUSIONS Our approach allowed the consistent identification of segmentation anomalies even in isolated sacra. Additionally, our outcomes either suggest that homeotic border shifts often affect multiple spinal regions in a unidirectional way, or that sacrum length is highly conserved perhaps due to functional constraints. Our results elucidate the potential clinical, biomechanical, and evolutionary significance of lumbosacral transitional vertebrae.
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Affiliation(s)
- Viktoria A Krenn
- Institute of Evolutionary Medicine, University of Zurich, Zürich, Switzerland
- Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria
| | - Cinzia Fornai
- Institute of Evolutionary Medicine, University of Zurich, Zürich, Switzerland
- Department of Evolutionary Anthropology, University of Vienna, Vienna, Austria
- VieSID, Vienna School of Interdisciplinary Dentistry, Klosterneuburg, Austria
| | - Nicole M Webb
- Institute of Evolutionary Medicine, University of Zurich, Zürich, Switzerland
- Department of Palaeoanthropology, Senckenberg Research Institute and Natural History Museum Frankfurt, Frankfurt, Germany
- Institute of Archaeological Sciences, Senckenberg Centre for Human Evolution and Palaeoenvironment, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Mirella A Woodert
- Institute of Evolutionary Medicine, University of Zurich, Zürich, Switzerland
| | - Helmut Prosch
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Martin Haeusler
- Institute of Evolutionary Medicine, University of Zurich, Zürich, Switzerland
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4
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Mulley JF. Regulation of posterior Hox genes by sex steroids explains vertebral variation in inbred mouse strains. J Anat 2022; 240:735-745. [PMID: 34747015 PMCID: PMC8930804 DOI: 10.1111/joa.13580] [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: 08/31/2021] [Revised: 10/08/2021] [Accepted: 10/21/2021] [Indexed: 11/29/2022] Open
Abstract
A series of elegant embryo transfer experiments in the 1950s demonstrated that the uterine environment could alter vertebral patterning in inbred mouse strains. In the intervening decades, attention has tended to focus on the technical achievements involved and neglected the underlying biological question: how can genetically homogenous individuals have a heterogenous number of vertebrae? Here I revisit these experiments and, with the benefit of knowledge of the molecular-level processes of vertebral patterning gained over the intervening decades, suggest a novel hypothesis for homeotic transformation of the last lumbar vertebra to the adjacent sacral type through regulation of Hox genes by sex steroids. Hox genes are involved in both axial patterning and development of male and female reproductive systems and have been shown to be sensitive to sex steroids in vitro and in vivo. Regulation of these genes by sex steroids and resulting alterations to vertebral patterning may hint at a deep evolutionary link between the ribless lumbar region of mammals and the switch from egg-laying to embryo implantation. An appreciation of the impact of sex steroids on Hox genes may explain some puzzling aspects of human disease, and highlights the spine as a neglected target for in utero exposure to endocrine disruptors.
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5
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Essay the (unusual) heuristic value of Hox gene clusters; a matter of time? Dev Biol 2022; 484:75-87. [PMID: 35182536 DOI: 10.1016/j.ydbio.2022.02.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 12/22/2022]
Abstract
Ever since their first report in 1984, Antennapedia-type homeobox (Hox) genes have been involved in such a series of interesting observations, in particular due to their conserved clustered organization between vertebrates and arthropods, that one may legitimately wonder about the origin of this heuristic value. In this essay, I first consider different examples where Hox gene clusters have been instrumental in providing conceptual advances, taken from various fields of research and mostly involving vertebrate embryos. These examples touch upon our understanding of genomic evolution, the revisiting of 19th century views on the relationships between development and evolution and the building of a new framework to understand long-range and pleiotropic gene regulation during development. I then discuss whether the high value of the Hox gene family, when considered as an epistemic object, is related to its clustered structure (and the absence thereof in some animal species) and, if so, what is it in such particular genetic oddities that made them so generous in providing the scientific community with interesting information.
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6
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Rojas CV, Olivares JI, Tutor PM, Sánchez M, Alemán Aguilera I. Ontogeny of morphological variations in the vertebral column: Prevalence and bony variability in young Spanish children. Ann Anat 2022; 240:151888. [PMID: 35032564 DOI: 10.1016/j.aanat.2022.151888] [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: 11/19/2021] [Revised: 01/07/2022] [Accepted: 01/08/2022] [Indexed: 10/19/2022]
Abstract
Pre- and postnatal development and variability in discrete vertebral traits have been poorly described in embryonic studies. Numerous authors have reported that these variations are observable only from adolescence; scientific publications on the vertebrae of fetuses and infants are scarce. Thus, the aims of this study were to (1) describe the ontogeny and variability of anatomical variations in the vertebral column of a Spanish infant population and (2) analyze the frequency and relationship between sex, age, and intertrait variables. A total of 4728 vertebrae from 197 skeletons were studied. The age at death ranged from 22 intrauterine weeks to 8 years. Twenty morphological traits related to vertebral column development were analyzed. A descriptive statistical analysis was performed, and the chi-square test was used to measure the relationship between sex, age, and intertrait variables. We observed that 88.32% of skeletons expressed discrete traits along the spine. In fetuses, the double transverse foramen and unclosed transverse process of the axis were the most prevalent traits. In infants older than one year, the appearance of the L5 cleft neural arch, unclosed transverse process of the atlas, and craniocaudal shifts were frequent. A significant result was found between sex and the unclosed transverse process in the axis. The intertrait relationship was significant for all traits that shared the same embryonic structure. Morphological variations became visible following the appearance of ossification centers during the pre- and postnatal periods, and their etiology was associated with embryonic development.
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Affiliation(s)
- Catherine Villoria Rojas
- Departamento de Medicina Legal, Psiquiatría y Anatomía Patológica, Universidad Complutense de Madrid, Spain.
| | - Javier Irurita Olivares
- Departamento de Medicina Legal, Toxicología y Antropología Física, Universidad de Granada, Spain.
| | - Pilar Mata Tutor
- Departamento de Medicina Legal, Psiquiatría y Anatomía Patológica, Universidad Complutense de Madrid, Spain.
| | - María Sánchez
- Departamento de Medicina Legal, Psiquiatría y Anatomía Patológica, Universidad Complutense de Madrid, Spain.
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7
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Schut PC, Brosens E, Van Dooren TJM, Galis F, Ten Broek CMA, Baijens IMM, Dremmen MHG, Tibboel D, Schol MP, de Klein A, Eggink AJ, Cohen-Overbeek TE. Exploring copy number variants in deceased fetuses and neonates with abnormal vertebral patterns and cervical ribs. Birth Defects Res 2020; 112:1513-1525. [PMID: 32755042 PMCID: PMC7689732 DOI: 10.1002/bdr2.1786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 07/03/2020] [Accepted: 07/21/2020] [Indexed: 12/13/2022]
Abstract
Background Cervical patterning abnormalities are rare in the general population, but one variant, cervical ribs, is particularly common in deceased fetuses and neonates. The discrepancy between the incidence in the general population and early mortality is likely due to indirect selection against cervical ribs. The cause for the co‐occurrence of cervical ribs and adverse outcome remains unidentified. Copy number variations resulting in gain or loss of specific genes involved in development and patterning could play a causative role. Methods Radiographs of 374 deceased fetuses and infants, including terminations of pregnancies, stillbirths and neonatal deaths, were assessed. Copy number profiles of 265 patients were determined using single nucleotide polymorphism array. Results 274/374 patients (73.3%) had an abnormal vertebral pattern, which was associated with congenital abnormalities. Cervical ribs were present in 188/374 (50.3%) and were more common in stillbirths (69/128 [53.9%]) and terminations of pregnancies (101/188 [53.7%]), compared to live births (18/58, 31.0%). Large (likely) deleterious copy number variants and aneuploidies were prevalent in these patients. None of the rare copy number variants were recurrent or overlapped with candidate genes for vertebral patterning. Conclusions The large variety of copy number variants in deceased fetuses and neonates with similar abnormalities of the vertebral pattern probably reflects the etiological heterogeneity of vertebral patterning abnormalities. This genetic heterogeneity corresponds with the hypothesis that cervical ribs can be regarded as a sign of disruption of critical, highly interactive stages of embryogenesis. The vertebral pattern can probably provide valuable information regarding fetal and neonatal outcome.
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Affiliation(s)
- Pauline C Schut
- Department of Obstetrics and Gynecology, Division of Obstetrics and Fetal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Erwin Brosens
- Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Tom J M Van Dooren
- Naturalis Biodiversity Center, Leiden, The Netherlands.,CNRS, Institute of Ecology and Environmental Sciences iEES Paris, Sorbonne University, Paris, France
| | | | | | - Inge M M Baijens
- Department of Obstetrics and Gynecology, Division of Obstetrics and Fetal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Marjolein H G Dremmen
- Department of Radiology, Division of Paediatric Radiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Dick Tibboel
- Department of Paediatric Surgery, Erasmus MC, Erasmus University Medical Center Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Martin P Schol
- Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Annelies de Klein
- Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Alex J Eggink
- Department of Obstetrics and Gynecology, Division of Obstetrics and Fetal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Titia E Cohen-Overbeek
- Department of Obstetrics and Gynecology, Division of Obstetrics and Fetal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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Evolution of the Mammalian Neck from Developmental, Morpho-Functional, and Paleontological Perspectives. J MAMM EVOL 2020. [DOI: 10.1007/s10914-020-09506-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
AbstractThe mammalian neck adopts a variety of postures during daily life and generates numerous head trajectories. Despite its functional diversity, the neck is constrained to seven cervical vertebrae in (almost) all mammals. Given this low number, an unexpectedly high degree of modularity of the mammalian neck has more recently been uncovered. This work aims to review neck modularity in mammals from a developmental, morpho-functional, and paleontological perspective and how high functional diversity evolved in the mammalian neck after the occurrence of meristic limitations. The fixed number of cervical vertebrae and the developmental modularity of the mammalian neck are closely linked to anterior Hox genes expression and strong developmental integration between the neck and other body regions. In addition, basic neck biomechanics promote morpho-functional modularity due to preferred motion axes in the cranio-cervical and cervico-thoracic junction. These developmental and biomechanical determinants result in the characteristic and highly conserved shape variation among the vertebrae that delimits morphological modules. The step-wise acquisition of these unique cervical traits can be traced in the fossil record. The increasing functional specialization of neck modules, however, did not evolve all at once but started much earlier in the upper than in the lower neck. Overall, the strongly conserved modularity in the mammalian neck represents an evolutionary trade-off between the meristic constraints and functional diversity. Although a morpho-functional partition of the neck is common among amniotes, the degree of modularity and the way neck disparity is realized is unique in mammals.
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9
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Miscarriage is associated with cervical ribs in thoracic outlet syndrome patients. Early Hum Dev 2020; 144:105027. [PMID: 32247157 DOI: 10.1016/j.earlhumdev.2020.105027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/23/2020] [Accepted: 03/23/2020] [Indexed: 11/22/2022]
Abstract
The constancy of the number of cervical vertebrae in mammals is probably the result of selection against associated variations. A survey among patients with and without cervical ribs showed an association between miscarriage and the presence of cervical ribs. This supports the hypothesized selection against variations in cervical vertebral number.
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10
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Partiot C, Guillon M, Peressinotto D, Castex D, Maureille B. Cervical ribs in human early life: morphological variability and first identification as a morbidity criterion in a past population. J Anat 2020; 237:119-132. [PMID: 32187701 DOI: 10.1111/joa.13178] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/16/2020] [Accepted: 02/14/2020] [Indexed: 10/24/2022] Open
Abstract
Despite the medical literature on supernumerary cervical ribs in extant adult samples, little is known about their development and occurrence in early infancy. The documentation of cervical ribs in modern samples of fetuses and neonates is indeed affected by ethical as well as technical limitations. The aim of the present study was to investigate their frequencies and morphological variability in the first known archaeological collection of very young children with this anatomical variant. The study sample comes from the 8B-51 necropolis on the Saï island (Sudan) and dates to the Classic Kerma Period (XVIIIe-XVIe centuries BC). It consists of 64 individuals deceased between 24 weeks of amenorrhoea and 2 years of age. Bilateral or unilateral cervical ribs were found in 27 individuals. A total of 43 cervical ribs were identified, 38 of which are fully preserved. According to these observations, at least 42% of the individuals have unilateral or bilateral cervical ribs, with an average maximum length of < 1 cm. This frequency is very high compared to those observed in contemporary adult samples (up to 3%). First, the comparison of our results with biological and genetic research demonstrating the link between the occurrence of cervical ribs and a reduced chance of survival during infancy allows the first identification of this trait as an indicator of morbidity in an archaeological collection, a morbidity to which a genetic homogeneity or even endogamy could contribute. Second, the number of ribs studied makes it possible to propose a morphological classification based on the general shape and the shape of the articular facets, classification that can be used tos refine the analyses of the trait in future samples.
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Affiliation(s)
- Caroline Partiot
- UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac Cedex, France
| | - Mark Guillon
- UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac Cedex, France.,Inrap, Boulevard de Verdun, Le Grand Quevilly, France
| | - David Peressinotto
- UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac Cedex, France.,Hades Archéologie, Balma, France
| | - Dominique Castex
- UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac Cedex, France
| | - Bruno Maureille
- UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac Cedex, France
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11
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Cervical ribs and other abnormalities of the vertebral pattern in children with esophageal atresia and anorectal malformations. Pediatr Res 2020; 87:773-778. [PMID: 31645054 DOI: 10.1038/s41390-019-0631-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/26/2019] [Accepted: 09/29/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND In mammals the vertebral column has a constant pattern, particularly in the cervical region, which is likely the result of stabilizing selection. The prevalence of cervical ribs and extended vertebral pattern abnormalities is increased in deceased fetuses and neonates and associated with structural and chromosomal anomalies. The hypothesized close interaction between vertebral patterning and organogenesis in early embryogenesis could be studied in children with esophageal atresia and anorectal malformations by evaluating the radiographs of the vertebral column and the type and number of associated anomalies METHODS: The vertebral pattern of 367 children diagnosed with an esophageal atresia (n = 135), anorectal malformation (n = 215), or both (n = 17) was assessed on radiographs. RESULTS The vertebral pattern was abnormal in 170/202 (84.2%) children in whom this could be assessed, and cervical ribs were present in 147/335 (43.9%). Extended vertebral pattern abnormalities became more frequent with an increasing number of associated structural abnormalities. Cervical ribs were particularly common in children with chromosomal and genetic abnormalities (18/20, 90.0%). CONCLUSIONS Cervical ribs are frequent and abnormal vertebral patterns are more extended in the presence of associated anomalies. These findings support the hypothesized selection against vertebral patterning variations and emphasize the relevance of assessment of the vertebral pattern.
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12
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Kudlicki A. Why a Constant Number of Vertebrae? Digital Control of Segmental Identity during Vertebrate Development: The Somite Cycle Controls a Digital, Chromatin-Based Counter That Defines Segmental Identity and Body Plans in Vertebrate Animals. Bioessays 2019; 42:e1900133. [PMID: 31755133 DOI: 10.1002/bies.201900133] [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: 08/01/2019] [Revised: 11/01/2019] [Indexed: 11/06/2022]
Abstract
It is not understood how the numbers and identities of vertebrae are controlled during mammalian development. The remarkable robustness and conservation of segmental numbers may suggest the digital nature of the underlying process. The study proposes a mechanism that allows cells to obtain and store the segmental information in digital form, and to produce a pattern of chromatin accessibility that in turn regulates Hox gene expression specific to the metameric segment. The model requires that a regulatory element be present such that the number of occurrences of the motif between two consecutive Hox genes equals the number of segments under the control of the anterior gene. This is true for the recently discovered hydroxyl radical cleavage 3bp-periodic (HRC3) motif, associated with histone modifications and developmental genes. The finding not only allows the correct prediction of the numbers of segments using only sequence information, but also resolves the 40-year-old enigma of the function of temporal and spatial collinearity of Hox genes. The logic of the mechanism is illustrated in the attached animated video. How different aspects of the proposed mechanism can be tested experimentally is also discussed.
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Affiliation(s)
- Andrzej Kudlicki
- Institute for Translational Sciences, Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, USA
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13
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Arlegi M, Veschambre‐Couture C, Gómez‐Olivencia A. Evolutionary selection and morphological integration in the vertebral column of modern humans. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 171:17-36. [DOI: 10.1002/ajpa.23950] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 07/03/2019] [Accepted: 09/26/2019] [Indexed: 01/22/2023]
Affiliation(s)
- Mikel Arlegi
- Departamento de Estratigrafía y Paleontología, Facultad de Ciencia y TecnologíaUniversidad del País Vasco‐Euskal Herriko Unibertsitatea (UPV/EHU) Leioa Spain
- Université de Bordeaux, PACEA UMR 5199 Pessac France
| | | | - Asier Gómez‐Olivencia
- Departamento de Estratigrafía y Paleontología, Facultad de Ciencia y TecnologíaUniversidad del País Vasco‐Euskal Herriko Unibertsitatea (UPV/EHU) Leioa Spain
- IKERBASQUE. Basque Foundation for Science Bizkaia Spain
- Centro UCM‐ISCIII de Investigación sobre Evolución y Comportamiento Humanos Madrid Spain
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14
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Williams SA, Spear JK, Petrullo L, Goldstein DM, Lee AB, Peterson AL, Miano DA, Kaczmarek EB, Shattuck MR. Increased variation in numbers of presacral vertebrae in suspensory mammals. Nat Ecol Evol 2019; 3:949-956. [DOI: 10.1038/s41559-019-0894-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 04/08/2019] [Indexed: 11/09/2022]
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15
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Love AC, Yoshida Y. Reflections on Model Organisms in Evolutionary Developmental Biology. Results Probl Cell Differ 2019; 68:3-20. [PMID: 31598850 DOI: 10.1007/978-3-030-23459-1_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This chapter reflects on and makes explicit the distinctiveness of reasoning practices associated with model organisms in the context of evolutionary developmental research. Model organisms in evo-devo instantiate a unique synthesis of model systems strategies from developmental biology and comparative strategies from evolutionary biology that negotiate a tension between developmental conservation and evolutionary change to address scientific questions about the evolution of development and the developmental basis of evolutionary change. We review different categories of model systems that have been advanced to understand practices found in the life sciences in order to comprehend how evo-devo model organisms instantiate this synthesis in the context of three examples: the starlet sea anemone and the evolution of bilateral symmetry, leeches and the origins of segmentation in bilaterians, and the corn snake to understand major evolutionary change in axial and appendicular morphology.
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Affiliation(s)
- Alan C Love
- Department of Philosophy and Minnesota Center for Philosophy of Science, University of Minnesota - Twin Cities, Minneapolis, MN, USA.
| | - Yoshinari Yoshida
- Department of Philosophy and Minnesota Center for Philosophy of Science, University of Minnesota - Twin Cities, Minneapolis, MN, USA
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16
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Schut P, Verdijk RM, Joosten M, Eggink AJ. Prenatal diagnosis of cervical ribs by three-dimensional ultrasound in a foetus with a herniated Dandy-Walker cyst. BMJ Case Rep 2018; 11:e225381. [PMID: 30567892 PMCID: PMC6303663 DOI: 10.1136/bcr-2018-225381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2018] [Indexed: 11/03/2022] Open
Abstract
We present a case report of a foetus with a herniated Dandy-Walker cyst and bilateral rudimentary cervical ribs. The cervical ribs were visualised prenatally by three-dimensional ultrasound and confirmed by post-termination radiography. The prevalence of cervical ribs is higher in deceased fetuses and neonates with or without structural abnormalities compared with healthy individuals and might be regarded as a marker of disadvantageous fetal development. We demonstrate that evaluation of the fetal vertebral pattern by three-dimensional ultrasonography, including the cervical region, is feasible and could provide valuable information regarding fetal and neonatal prognosis.
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Affiliation(s)
- Pauline Schut
- Prenatal Medicine, Erasmus MC, Rotterdam, The Netherlands
| | | | | | - Alex J Eggink
- Department of Obstetrics and Gynecology, Erasmus MC, Rotterdam, The Netherlands
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17
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Shapiro LJ, Kemp AD. Functional and developmental influences on intraspecific variation in catarrhine vertebrae. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 168:131-144. [DOI: 10.1002/ajpa.23730] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 09/13/2018] [Accepted: 09/26/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Liza J. Shapiro
- Department of Anthropology University of Texas at Austin Austin Texas
| | - Addison D. Kemp
- Department of Anthropology University of Texas at Austin Austin Texas
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Galis F, Metz JA, van Alphen JJ. Development and Evolutionary Constraints in Animals. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2018. [DOI: 10.1146/annurev-ecolsys-110617-062339] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We review the evolutionary importance of developmental mechanisms in constraining evolutionary changes in animals—in other words, developmental constraints. We focus on hard constraints that can act on macroevolutionary timescales. In particular, we discuss the causes and evolutionary consequences of the ancient metazoan constraint that differentiated cells cannot divide and constraints against changes of phylotypic stages in vertebrates and other higher taxa. We conclude that in all cases these constraints are caused by complex and highly controlled global interactivity of development, the disturbance of which has grave consequences. Mutations that affect such global interactivity almost unavoidably have many deleterious pleiotropic effects, which will be strongly selected against and will lead to long-term evolutionary stasis. The discussed developmental constraints have pervasive consequences for evolution and critically restrict regeneration capacity and body plan evolution.
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Affiliation(s)
- Frietson Galis
- Naturalis Biodiversity Center, 2333 CR Leiden, The Netherlands
| | - Johan A.J. Metz
- Naturalis Biodiversity Center, 2333 CR Leiden, The Netherlands
- International Institute for Applied Systems Analysis, A-2361 Laxenburg, Austria
- Mathematical Institute, University of Leiden; 2333 CA Leiden, The Netherlands
| | - Jacques J.M. van Alphen
- Naturalis Biodiversity Center, 2333 CR Leiden, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE Amsterdam, The Netherlands
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Yun S, Park S, Park JG, Huh JD, Shin YG, Yun JH. Spinal Enumeration by Morphologic Analysis of Spinal Variants: Comparison to Counting in a Cranial-To-Caudal Manner. Korean J Radiol 2018; 19:1140-1146. [PMID: 30386145 PMCID: PMC6201970 DOI: 10.3348/kjr.2018.19.6.1140] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 05/06/2018] [Indexed: 11/22/2022] Open
Abstract
Objective To compare the spinal enumeration methods that establish the first lumbar vertebra in patients with spinal variants. Materials and Methods Of the 1446 consecutive patients who had undergone computed tomography of the spine from March 2012 to July 2016, 100 patients (62 men, 38 women; mean age, 47.9 years; age range, 19-88 years) with spinal variants were included. Two radiologists (readers 1 and 2) established the first lumbar vertebra through morphologic analysis of the thoracolumbar junction, and labeled the vertebra by counting in a cranial-to-caudal manner. Inter-observer agreement was established. Additionally, reader 1 detected the 20th vertebra under the assumption that there are 12 thoracic vertebra, and then classified it as a thoracic vertebra, lumbar vertebra, or thoracolumbar transitional vertebra (TLTV), on the basis of morphologic analysis. Results The first lumbar vertebra, as established by morphologic analysis, was labeled by each reader as the 21st segment in 65.0% of the patients, as the 20th segment in 31.0%, and as the 19th segment in 4.0%. Inter-observer agreement between the two readers in determining the first lumbar vertebra, based on morphologic analysis, was nearly perfect (κ value: 1.00). The 20th vertebra was morphologically classified as a TLTV in 60.0% of the patients, as the first lumbar segment in 31.0%, as the second lumbar segment in 4.0%, and as a thoracic segment in 5.0%. Conclusion The establishment of the first lumbar vertebra using morphologic characteristics of the thoracolumbar junction in patients with spinal variants was consistent with the morphologic traits of vertebral segmentation.
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Affiliation(s)
- Sam Yun
- Department of Radiology, Kosin University Gospel Hospital, Busan 49267, Korea
| | - Sekyoung Park
- Department of Radiology, Kosin University Gospel Hospital, Busan 49267, Korea
| | - Jung Gu Park
- Department of Radiology, Kosin University Gospel Hospital, Busan 49267, Korea
| | - Jin Do Huh
- Department of Radiology, Kosin University Gospel Hospital, Busan 49267, Korea
| | - Young Gyung Shin
- Department of Radiology, Kosin University Gospel Hospital, Busan 49267, Korea
| | - Jong Hyouk Yun
- Department of Radiology, Kosin University Gospel Hospital, Busan 49267, Korea
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20
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Brocal J, De Decker S, José-López R, Manzanilla EG, Penderis J, Stalin C, Bertram S, Schoenebeck JJ, Rusbridge C, Fitzpatrick N, Gutierrez-Quintana R. C7 vertebra homeotic transformation in domestic dogs - are Pug dogs breaking mammalian evolutionary constraints? J Anat 2018; 233:255-265. [PMID: 29761492 DOI: 10.1111/joa.12822] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2018] [Indexed: 12/20/2022] Open
Abstract
The number of cervical vertebrae in mammals is almost constant at seven, regardless of their neck length, implying that there is selection against variation in this number. Homebox (Hox) genes are involved in this evolutionary mammalian conservation, and homeotic transformation of cervical into thoracic vertebrae (cervical ribs) is a common phenotypic abnormality when Hox gene expression is altered. This relatively benign phenotypic change can be associated with fatal traits in humans. Mutations in genes upstream of Hox, inbreeding and stressors during organogenesis can also cause cervical ribs. The aim of this study was to describe the prevalence of cervical ribs in a large group of domestic dogs of different breeds, and explore a possible relation with other congenital vertebral malformations (CVMs) in the breed with the highest prevalence of cervical ribs. By phenotyping we hoped to give clues as to the underlying genetic causes. Twenty computed tomography studies from at least two breeds belonging to each of the nine groups recognized by the Federation Cynologique Internationale, including all the brachycephalic 'screw-tailed' breeds that are known to be overrepresented for CVMs, were reviewed. The Pug dog was more affected by cervical ribs than any other breed (46%; P < 0.001), and was selected for further analysis. No association was found between the presence of cervical ribs and vertebral body formation defect, bifid spinous process, caudal articular process hypoplasia/aplasia and an abnormal sacrum, which may infer they have a different aetiopathogenesis. However, Pug dogs with cervical ribs were more likely to have a transitional thoraco-lumbar vertebra (P = 0.041) and a pre-sacral vertebral count of 26 (P < 0.001). Higher C7/T1 dorsal spinous processes ratios were associated with the presence of cervical ribs (P < 0.001), supporting this is a true homeotic transformation. Relaxation of the stabilizing selection has likely occurred, and the Pug dog appears to be a good naturally occurring model to further investigate the aetiology of cervical ribs, other congenital vertebral anomalies and numerical alterations.
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Affiliation(s)
- J Brocal
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - S De Decker
- Department of Veterinary Clinical Science and Services, The Royal Veterinary College, University of London, North Mymms, Hertfordshire, UK
| | - R José-López
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - E G Manzanilla
- Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
| | - J Penderis
- Vet-Extra Neurology, Broadleys Veterinary Hospital, Stirling, UK
| | - C Stalin
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - S Bertram
- Department of Veterinary Clinical Science and Services, The Royal Veterinary College, University of London, North Mymms, Hertfordshire, UK
| | - J J Schoenebeck
- Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Midlothian, UK
| | - C Rusbridge
- Fitzpatrick Referrals, Eashing, Surrey, UK.,School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, Surrey, UK
| | | | - R Gutierrez-Quintana
- School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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Schut PC, Ten Broek CMA, Cohen-Overbeek TE, Bugiani M, Steegers EAP, Eggink AJ, Galis F. Increased prevalence of abnormal vertebral patterning in fetuses and neonates with trisomy 21. J Matern Fetal Neonatal Med 2018; 32:2280-2286. [PMID: 29353507 DOI: 10.1080/14767058.2018.1431622] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To assess the prevalence of an abnormal number of ribs in a cohort of fetuses and neonates with trisomy 21 and compare this with a subgroup of fetuses without anomalies. MATERIALS AND METHODS Radiographs of 67 deceased fetuses, neonates, and infants that were diagnosed with trisomy 21 were reviewed. Terminations of pregnancy were included. The control group was composed of 107 deceased fetuses, neonates, and infants without known chromosomal abnormalities, structural malformations, infections or placental pathology. Cases in which the number of thoracic ribs or presence of cervical ribs could not be reliably assessed were excluded. The literature concerning vertebral patterning in trisomy 21 cases and healthy subjects was reviewed. RESULTS Absent or rudimentary 12th thoracic ribs were found in 26/54 (48.1%) cases with trisomy 21 and cervical ribs were present in 27/47 (57.4%) cases. This prevalence was significantly higher compared to controls (28/100, 28.0%, Χ2(1) = 6.252, p = .012 and 28/97, 28.9%, Χ2(1) = 10.955, p < .001, respectively). CONCLUSIONS Rudimentary or absent 12th thoracic ribs and cervical ribs are significantly more prevalent in deceased fetuses and infants with trisomy 21.
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Affiliation(s)
- Pauline C Schut
- a Department of Obstetrics and Gynecology , Erasmus MC University Medical Center , Division of Obstetrics and Prenatal Medicine , Rotterdam , The Netherlands
| | | | - Titia E Cohen-Overbeek
- a Department of Obstetrics and Gynecology , Erasmus MC University Medical Center , Division of Obstetrics and Prenatal Medicine , Rotterdam , The Netherlands
| | - Marianna Bugiani
- c Department of Pathology , VU University Medical Centre , Amsterdam , The Netherlands
| | - Eric A P Steegers
- a Department of Obstetrics and Gynecology , Erasmus MC University Medical Center , Division of Obstetrics and Prenatal Medicine , Rotterdam , The Netherlands
| | - Alex J Eggink
- a Department of Obstetrics and Gynecology , Erasmus MC University Medical Center , Division of Obstetrics and Prenatal Medicine , Rotterdam , The Netherlands
| | - Frietson Galis
- b Naturalis Biodiversity Center , Leiden , The Netherlands
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22
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Tague RG. Proximate cause, anatomical correlates, and obstetrical implication of a supernumerary lumbar vertebra in humans. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 165:444-456. [PMID: 29159938 DOI: 10.1002/ajpa.23361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Three issues are considered on variation in number of presacral vertebrae (PSV) in humans: (1) sexual difference in number of PSV, (2) inactivation of Hoxd-11 gene as etiology for a supernumerary lumbar vertebra, and (3) anatomical correlates of a supernumerary lumbar vertebra, including lumbar-sacral nearthrosis, and pelvic size. MATERIALS AND METHODS Sample was 407 skeletonized females and 1,318 males from United States; ages at death were 20 to 49 years. Two subsamples of males were used: (1) 98 with modal numbers of cervical, thoracic, lumbar, and sacral vertebrae (PSV = 24) and (2) 45 with a supernumerary lumbar vertebra but modal numbers for other vertebral segments (PSV = 25). Measurements were taken of ulna, second metacarpal, vertebrae, femur, and pelvis; presence of lumbar-sacral nearthrosis was observed. RESULTS Although 90% of females and males have 24 PSV, females have higher frequency of 23 PSV and males have higher frequency of 25 PSV. Compared to males with 24 PSV, males with 25 PSV and supernumerary lumbar vertebra show (1) no difference in anatomies associated with inactivation of Hoxd-11, and (2) higher frequency of lumbar-sacral nearthrosis and smaller pelvic inlet circumference. DISCUSSION Sexual difference in number of PSV may be due to tempo of somite formation and Hox gene activation. Hypothesis is not supported that a supernumerary lumbar vertebra is due to inactivation of Hoxd-11. The presence of a supernumerary lumbar vertebra is associated with small pelvic inlet circumference, which can be obstetrically disadvantageous.
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Affiliation(s)
- Robert G Tague
- Department of Geography and Anthropology, Louisiana State University, Baton Rouge, Louisiana, 70803
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23
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van der Geer AAE, Galis F. High incidence of cervical ribs indicates vulnerable condition in Late Pleistocene woolly rhinoceroses. PeerJ 2017; 5:e3684. [PMID: 28875067 PMCID: PMC5580387 DOI: 10.7717/peerj.3684] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 07/22/2017] [Indexed: 11/20/2022] Open
Abstract
Mammals as a rule have seven cervical vertebrae, a number that remains remarkably constant. Changes of this number are associated with major congenital abnormalities (pleiotropic effects) that are, at least in humans, strongly selected against. Recently, it was found that Late Pleistocene mammoths (Mammuthus primigenius) from the North Sea have an unusually high incidence of abnormal cervical vertebral numbers, approximately ten times higher than that of extant elephants. Abnormal numbers were due to the presence of large cervical ribs on the seventh vertebra, indicating a homeotic change from a cervical rib-less vertebra into a thoracic rib-bearing vertebra. The high incidence of cervical ribs indicates a vulnerable condition and is thought to be due to inbreeding and adverse conditions that may have impacted early pregnancies in declining populations. In this study we investigated the incidence of cervical ribs in another extinct Late Pleistocene megaherbivore from the North Sea and the Netherlands, the woolly rhinoceros (Coelodonta antiquitatis). We show that the incidence of abnormal cervical vertebral numbers in the woolly rhinoceros is unusually high for mammals (15,6%, n = 32) and much higher than in extant Rhinoceratidae (0%, n = 56). This indicates that woolly rhinoceros lived under vulnerable conditions, just like woolly mammoths. The vulnerable condition may well have contributed to their eventual extinction.
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Affiliation(s)
- Alexandra A E van der Geer
- Naturalis Biodiversity Center, Leiden, the Netherlands.,Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Zografou, Greece
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24
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Ten Broek CMA, Bots J, Bugiani M, Galis F, Van Dongen S. No relationship between vertebral column shifts and limb fluctuating asymmetry in human foetuses. PeerJ 2017. [PMID: 28626605 PMCID: PMC5470575 DOI: 10.7717/peerj.3359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Disturbance from the normal developmental trajectory of a trait during growth—the so-called developmental instability—can be observed morphologically through phenodeviants and subtle deviations from perfect symmetry (fluctuating asymmetry). This study investigates the relationship between phenodeviance in the human vertebral column (as a result of axial patterning defects) and limb fluctuating asymmetry. Since both types of markers of developmental instability have been found associated with congenital abnormalities in humans, we anticipate a relationship between them if the concept of developmental instability, measured through either phenodeviants or asymmetry, would reflect an organism-wide process. Yet we did not find any support for this hypothesis. We argue that the vast differences in the developmental processes involved in both systems renders these two markers of developmental instability unrelated, in spite of their associations with other congenital abnormalities. Our results thus contribute to the growing awareness that developmental instability is not an organism-wide property.
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Affiliation(s)
- Clara M A Ten Broek
- Naturalis Biodiversity Center, Leiden, Netherlands.,Evolutionary Ecology Group, Department of Biology, Universiteit Antwerpen, Wilrijk, Antwerp, Belgium
| | - Jessica Bots
- Evolutionary Ecology Group, Department of Biology, Universiteit Antwerpen, Wilrijk, Antwerp, Belgium
| | - Marianna Bugiani
- Department of Pathology, VU Medical Center, Amsterdam, Netherlands
| | | | - Stefan Van Dongen
- Evolutionary Ecology Group, Department of Biology, Universiteit Antwerpen, Wilrijk, Antwerp, Belgium
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25
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Karapetian MK. Discrete morphological variants of human cervical vertebrae: Exploring pattern of distribution and biological significance. HOMO-JOURNAL OF COMPARATIVE HUMAN BIOLOGY 2017; 68:176-198. [PMID: 28404241 DOI: 10.1016/j.jchb.2017.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 03/04/2017] [Indexed: 10/20/2022]
Abstract
Studies on discrete traits of the human cervical vertebrae, appearing at certain intervals during the last century, posed some questions regarding evolutionary processes that human cervical spine underwent during phylogenesis. To address questions of significance of these morphological traits we need first a good knowledge of the extent of their variation in modern humans. The aim of the current work was to integrate available data on the occurrence of various non-metric traits in the human cervical spine and search for the pattern of their distribution on intra- and inter-population levels. The study was based on data from five osteological samples from North America (Terry and Grant collections) and Russia (mid 20th c. and 18th c.); and data taken from literature. Traits were categorized into rare (<3%), low frequency (up to 10%), often encountered (10-30%) and characteristic for modern humans (>50% on average). Several traits showed mild to strong association with each other indicating interrelation between various spine characteristics. Of the traits analyzed, the following had consistent pattern of sex-related variability: complete dorsal ponticle, bifid spinous processes and cervical ribs; and ancestry-related variability: dorsal ponticle and bifid spinous processes. Each ancestry group (European, African, Asian and North American) had its specifics regarding the latter two traits which might be related to genetic isolation. Most of the traits, however, showed relatively similar pattern of distribution among various populations, including the pattern of within-spine variability. This suggests a common intraspecific pattern and a possible link to some fundamental characteristics of the human vertebral column.
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Affiliation(s)
- M K Karapetian
- Research Institute and Museum of Anthropology, Lomonosov Moscow State University, Moscow 125009, Russia.
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26
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Tague RG. Sacral Variability in Tailless Species: Homo sapiens
and Ochotona princeps. Anat Rec (Hoboken) 2017; 300:798-809. [DOI: 10.1002/ar.23555] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 10/05/2016] [Accepted: 11/26/2016] [Indexed: 12/29/2022]
Affiliation(s)
- Robert G. Tague
- Department of Geography and Anthropology; Louisiana State University; Baton Rouge Louisiana
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27
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Developmental Origins of Limb Developmental Instability in Human Fetuses: Many Abnormalities Make the Difference. Symmetry (Basel) 2017. [DOI: 10.3390/sym9040051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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28
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Adverse Fetal and Neonatal Outcome and an Abnormal Vertebral Pattern: A Systematic Review. Obstet Gynecol Surv 2016; 71:741-750. [DOI: 10.1097/ogx.0000000000000388] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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The Epidemiological, Morphological, and Clinical Aspects of the Cervical Ribs in Humans. BIOMED RESEARCH INTERNATIONAL 2016; 2016:8034613. [PMID: 27975060 PMCID: PMC5126392 DOI: 10.1155/2016/8034613] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 12/22/2022]
Abstract
A familiarity with the anatomy of some types of bone anomalies is necessary for clinicians involved in many medical areas. The aim of this paper is to review the newest literature concerning the morphology, embryology, clinical image, and therapeutic methods of the cervical ribs in the humans. The incidence of cervical ribs has been found to vary from 0.58% in Malaysian population to 6.2% in Turkish population. Cervical ribs have clinical implications that are generally divided into neurological or vascular. This study is of particular importance for clinicians, as early identification of cervical ribs may prevent life-threatening complications.
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Oostra RJ, Boer L, van der Merwe AE. Paleodysmorphology and paleoteratology: Diagnosing and interpreting congenital conditions of the skeleton in anthropological contexts. Clin Anat 2016; 29:878-91. [PMID: 27554863 DOI: 10.1002/ca.22769] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 08/10/2016] [Accepted: 08/19/2016] [Indexed: 11/08/2022]
Abstract
Most congenital conditions have low prevalence, but collectively they occur in a few percent of all live births. Congenital conditions are rarely encountered in anthropological studies, not least because many of them have no obvious effect on the skeleton. Here, we discuss two groups of congenital conditions that specifically affect the skeleton, either qualitatively or quantitatively. Skeletal dysplasias (osteochondrodysplasias) interfere with the histological formation, growth and maturation of skeletal tissues leading to diminished postural length, but the building plan of the body is unaffected. Well- known skeletal dysplasias represented in the archeological record include osteogenesis imperfecta and achondroplasia. Dysostoses, in contrast, interfere with the building plan of the body, leading to e.g. missing or extraskeletal elements, but the histology of the skeletal tissues is unaffected. Dysostoses can concern the extremities (e.g., oligodactyly and polydactyly), the vertebral column (e.g., homeotic and meristic anomalies), or the craniofacial region. Conditions pertaining to the cranial sutures, i.e., craniosynostoses, can be either skeletal dysplasias or dysostoses. Congenital conditions that are not harmful to the individual are known as anatomical variations, several of which have a high and population-specific prevalence that could potentially make them useful for determining ethnic origins. In individual cases, specific congenital conditions could be determinative in establishing identity, provided that ante-mortem registration of those conditions was ensured. Clin. Anat. 29:878-891, 2016. © 2016 The Authors Clinical Anatomy published by Wiley Periodicals, Inc. on behalf of American Association of Clinical Anatomists.
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Affiliation(s)
- Roelof-Jan Oostra
- Department of Anatomy, Embryology and Physiology, University of Amsterdam, Academic Medical Center, Amsterdam, The Netherlands.
| | - Lucas Boer
- Department of Anatomy and Museum for Anatomy and Pathology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Alie E van der Merwe
- Department of Anatomy, Embryology and Physiology, University of Amsterdam, Academic Medical Center, Amsterdam, The Netherlands
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Veraa S, Bergmann W, van den Belt AJ, Wijnberg I, Back W. EX VIVO COMPUTED TOMOGRAPHIC EVALUATION OF MORPHOLOGY VARIATIONS IN EQUINE CERVICAL VERTEBRAE. Vet Radiol Ultrasound 2016; 57:482-8. [DOI: 10.1111/vru.12393] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 05/25/2016] [Accepted: 05/27/2016] [Indexed: 11/27/2022] Open
Affiliation(s)
- Stefanie Veraa
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine; Utrecht University; Yalelaan 110, 3584 CM (Veraa, van den Belt)
| | - Wilhelmina Bergmann
- Department of Pathobiology, Faculty of Veterinary Medicine; Utrecht University; Yalelaan 1, 3584 CL (Bergmann)
| | - Antoon-Jan van den Belt
- Division of Diagnostic Imaging, Faculty of Veterinary Medicine; Utrecht University; Yalelaan 110, 3584 CM (Veraa, van den Belt)
| | - Inge Wijnberg
- Department of Equine Sciences, Faculty of Veterinary Medicine; Utrecht University; Yalelaan 114, 3584 CM (Wijnberg, Back) Utrecht The Netherlands
| | - Willem Back
- Department of Equine Sciences, Faculty of Veterinary Medicine; Utrecht University; Yalelaan 114, 3584 CM (Wijnberg, Back) Utrecht The Netherlands
- Department of Surgery and Anaesthesiology of Domestic Animals, Faculty of Veterinary Medicine; Ghent University; Salisburylaan 133, B-9820 Merelbeke Belgium (Back)
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Slijepčević M, Galis F, Arntzen JW, Ivanović A. Homeotic transformations and number changes in the vertebral column of Triturus newts. PeerJ 2015; 3:e1397. [PMID: 26587355 PMCID: PMC4647568 DOI: 10.7717/peerj.1397] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/20/2015] [Indexed: 01/23/2023] Open
Abstract
We explored intraspecific variation in vertebral formulae, more specifically the variation in the number of thoracic vertebrae and frequencies of transitional sacral vertebrae in Triturus newts (Caudata: Salamandridae). Within salamandrid salamanders this monophyletic group shows the highest disparity in the number of thoracic vertebrae and considerable intraspecific variation in the number of thoracic vertebrae. Triturus species also differ in their ecological preferences, from predominantly terrestrial to largely aquatic. Following Geoffroy St. Hilaire's and Darwin's rule which states that structures with a large number of serially homologous repetitive elements are more variable than structures with smaller numbers, we hypothesized that the variation in vertebral formulae increases in more elongated species with a larger number of thoracic vertebrae. We furthermore hypothesized that the frequency of transitional vertebrae will be correlated with the variation in the number of thoracic vertebrae within the species. We also investigated potential effects of species hybridization on the vertebral formula. The proportion of individuals with a number of thoracic vertebrae different from the modal number and the range of variation in number of vertebrae significantly increased in species with a larger number of thoracic vertebrae. Contrary to our expectation, the frequencies of transitional vertebrae were not correlated with frequencies of change in the complete vertebrae number. The frequency of transitional sacral vertebra in hybrids did not significantly differ from that of the parental species. Such a pattern could be a result of selection pressure against transitional vertebrae and/or a bias towards the development of full vertebrae numbers. Although our data indicate relaxed selection for vertebral count changes in more elongated, aquatic species, more data on different selective pressures in species with different numbers of vertebrae in the two contrasting, terrestrial and aquatic environments are needed to test for causality.
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Affiliation(s)
- Maja Slijepčević
- Institute for Biological Research “Siniša Stanković”, University of Belgrade, Belgrade, Serbia
| | | | | | - Ana Ivanović
- Naturalis Biodiversity Center, Leiden, The Netherlands
- Institute of Zoology, Faculty of Biology, University of Belgrade, Belgrade, Serbia
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Fast running restricts evolutionary change of the vertebral column in mammals. Proc Natl Acad Sci U S A 2014; 111:11401-6. [PMID: 25024205 DOI: 10.1073/pnas.1401392111] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The mammalian vertebral column is highly variable, reflecting adaptations to a wide range of lifestyles, from burrowing in moles to flying in bats. However, in many taxa, the number of trunk vertebrae is surprisingly constant. We argue that this constancy results from strong selection against initial changes of these numbers in fast running and agile mammals, whereas such selection is weak in slower-running, sturdier mammals. The rationale is that changes of the number of trunk vertebrae require homeotic transformations from trunk into sacral vertebrae, or vice versa, and mutations toward such transformations generally produce transitional lumbosacral vertebrae that are incompletely fused to the sacrum. We hypothesize that such incomplete homeotic transformations impair flexibility of the lumbosacral joint and thereby threaten survival in species that depend on axial mobility for speed and agility. Such transformations will only marginally affect performance in slow, sturdy species, so that sufficient individuals with transitional vertebrae survive to allow eventual evolutionary changes of trunk vertebral numbers. We present data on fast and slow carnivores and artiodactyls and on slow afrotherians and monotremes that strongly support this hypothesis. The conclusion is that the selective constraints on the count of trunk vertebrae stem from a combination of developmental and biomechanical constraints.
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Reumer JWF, Ten Broek CMA, Galis F. Extraordinary incidence of cervical ribs indicates vulnerable condition in Late Pleistocene mammoths. PeerJ 2014; 2:e318. [PMID: 24711969 PMCID: PMC3970796 DOI: 10.7717/peerj.318] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 03/03/2014] [Indexed: 11/26/2022] Open
Abstract
The number of cervical vertebrae in mammals is highly conserved at seven. We have shown that changes of this number are selected against due to a coupling with major congenital abnormalities (pleiotropic effects). Here we show that the incidence of abnormal cervical vertebral numbers in Late Pleistocene mammoths from the North Sea is high (33.3%) and approximately 10 times higher than that of extant elephants (3.6%). Abnormal numbers were due to the presence of large cervical ribs on the seventh vertebra, which we deduced from the presence of rib articulation facets on sixth (posterior side) and seventh (anterior side) cervical vertebrae. The incidence of abnormal cervical vertebral numbers in mammoths appears to be much higher than in other mammalian species, apart from exceptional sloths, manatees and dugongs and indicates a vulnerable condition. We argue that the increased incidence of cervical ribs in mammoths is probably caused by inbreeding and adverse conditions that impact early pregnancies in declining populations close to extinction in the Late Pleistocene.
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Affiliation(s)
- Jelle W F Reumer
- Natural History Museum , Rotterdam , The Netherlands ; Faculty of Geosciences, Utrecht University , Utrecht , The Netherlands
| | - Clara M A Ten Broek
- Naturalis Biodiversity Center, Terrestrial Zoology/Geology , Leiden , The Netherlands ; University Antwerp, Evolutionary Ecology Group , Antwerp , Belgium
| | - Frietson Galis
- Naturalis Biodiversity Center, Terrestrial Zoology/Geology , Leiden , The Netherlands
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ten Broek CMA, Bots J, Varela-Lasheras I, Bugiani M, Galis F, Van Dongen S. Amniotic fluid deficiency and congenital abnormalities both influence fluctuating asymmetry in developing limbs of human deceased fetuses. PLoS One 2013; 8:e81824. [PMID: 24312362 PMCID: PMC3842303 DOI: 10.1371/journal.pone.0081824] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 10/17/2013] [Indexed: 11/19/2022] Open
Abstract
Fluctuating asymmetry (FA), as an indirect measure of developmental instability (DI), has been intensively studied for associations with stress and fitness. Patterns, however, appear heterogeneous and the underlying causes remain largely unknown. One aspect that has received relatively little attention in the literature is the consequence of direct mechanical effects on asymmetries. The crucial prerequisite for FA to reflect DI is that environmental conditions on both sides should be identical. This condition may be violated during early human development if amniotic fluid volume is deficient, as the resulting mechanical pressures may increase asymmetries. Indeed, we showed that limb bones of deceased human fetuses exhibited increased asymmetry, when there was not sufficient amniotic fluid (and, thus, space) in the uterine cavity. As amniotic fluid deficiency is known to cause substantial asymmetries and abnormal limb development, these subtle asymmetries are probably at least in part caused by the mechanical pressures. On the other hand, deficiencies in amniotic fluid volume are known to be associated with other congenital abnormalities that may disturb DI. More specifically, urogenital abnormalities can directly affect/reduce amniotic fluid volume. We disentangled the direct mechanical effects on FA from the indirect effects of urogenital abnormalities, the latter presumably representing DI. We discovered that both factors contributed significantly to the increase in FA. However, the direct mechanical effect of uterine pressure, albeit statistically significant, appeared less important than the effects of urogenital abnormalities, with an effect size only two-third as large. We, thus, conclude that correcting for the relevant direct factors allowed for a representative test of the association between DI and stress, and confirmed that fetuses form a suitable model system to increase our understanding in patterns of FA and symmetry development.
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Affiliation(s)
- Clara Mariquita Antoinette ten Broek
- Group of Evolutionary Ecology, University of Antwerp, Antwerp, Belgium
- Department of Terrestrial Zoology, Naturalis Biodiversity Center, Leiden, The Netherlands
- * E-mail:
| | - Jessica Bots
- Group of Evolutionary Ecology, University of Antwerp, Antwerp, Belgium
| | - Irma Varela-Lasheras
- Department of Patterning and Morphogenesis, Gulbenkian Institute of Science, Oeiros, Portugal
| | - Marianna Bugiani
- Department of Pathology, VU Medical Centre, Amsterdam, The Netherlands
| | - Frietson Galis
- Department of Terrestrial Zoology, Naturalis Biodiversity Center, Leiden, The Netherlands
| | - Stefan Van Dongen
- Group of Evolutionary Ecology, University of Antwerp, Antwerp, Belgium
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