Journal of Morphology最新文献

{"title":"Aplacophoran traits in the late Ordovician septemchitonid polyplacophorans","authors":"Jerzy Dzik","doi":"10.1002/jmor.21700","DOIUrl":"10.1002/jmor.21700","url":null,"abstract":"<p>A sample of phosphatized, originally calcareous, mollusk shells from the Katian age uppermost Mójcza Limestone at its type locality yielded a few hundred polyplacophoran plates. The chelodids are very rare among them. Three septemchitonid species dominate. They represent a gradation from underived steep roof-like plates to almost cylindrical ones, leaving only a narrow ventral slit for the foot. Apparently, this represents the first step toward the extremely derived ‘segmented clam’ Bauplan of the Silurian <i>Carnicoleus</i>, with plates completely closed at the venter except for the mouth and anal openings. To enable growth, the plates became thinner and more flexible (or perhaps resorbed) along the dorsum. The tendency toward reduction of the ventral gap of the plates in the early Paleozoic septemchitonid polyplacophorans implies their lack of ability to cling to the substrate with a muscular foot. In compensation, their plates changed toward a more efficient protective function, covering the animal body sides more and more completely. This may explain the origin of the ventral furrow of extant solenogasters hiding the rudimentary foot. An opposite route was chosen by the coeval <i>Acaenoplax</i> lineage, in which the plates did not contact each other, exposing much of the soft body on the dorsum. In both cases the animals appeared to be worm-like, perhaps representing different ways of evolution from the Paleozoic chitons to the extant aplacophorans.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140876601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative morphology of the oropharyngeal denticles in the order Rhinopristiformes and its functional implications (Chondrichthyes: Batoidea)","authors":"Dhayana C. S. Oliveira,&nbsp;Karla D. A. Soares","doi":"10.1002/jmor.21708","DOIUrl":"10.1002/jmor.21708","url":null,"abstract":"<p>Guitarfishes and sawfishes are included in the order Rhinopristiformes, which currently encompasses five families: Pristidae, Rhinobatidae, Trygonorrhinidae, Rhinidae and Glaucostegidae. Considering the low number of studies focused on oral structures in Rhinopristiformes and the need to better understand their internal morphology, this study aimed to (1) evaluate and describe the morphological variation of the oropharyngeal denticles of guitarfishes and sawfish; (2) evaluate and describe the ontogenetic and sexual variation of the oropharyngeal denticles of <i>Zapteryx brevirostris</i>; (3) propose characters potentially useful for taxonomic and systematic purposes and (4) discuss the possible functions and advantages of these structures. Tissue samples were taken from the oropharyngeal region of specimens preserved in 70% alcohol and then prepared for visualization in scanning electron microscopy. A new method for sampling the pharynx region is proposed herein. Considerable morphological variation between families and genera was observed. However, no variation between conspecifics was found. Regional variations of denticles when examining a single individual were observed in shape, ornamentation, and orientation. In <i>Zapteryx brevirostris</i>, males had a significantly higher density of denticles in the ventral region than females and lower densities were observed in juveniles. The four characters discussed here are based on the presence of keels, number of cusps, distal end elongation and width/length ratio of the oropharyngeal denticles. Among the possible functions and advantages of these structures are the improvement of food adherence, tissue protection against food abrasion and parasitism, and attenuation of hydrodynamic drag in the oropharyngeal cavity during food ingestion.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140891884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlated evolution of beak and braincase morphology is present only in select bird clades","authors":"Xiaoni Xu,&nbsp;Rossy Natale","doi":"10.1002/jmor.21703","DOIUrl":"10.1002/jmor.21703","url":null,"abstract":"<p>Complex morphological structures, such as skulls or limbs, are often composed of multiple morphological components (e.g., bones, sets of bones) that may evolve in a covaried manner with one another. Previous research has reached differing conclusions on the number of semi-independent units, or modules, that exist in the evolution of structures and on the strength of the covariation, or integration, between these hypothesized modules. We focus on the avian skull as an example of a complex morphological structure for which highly variable conclusions have been reached in the numerous studies analyzing support for a range of simple to complex modularity hypotheses. We hypothesized that past discrepancies may stem from both the differing densities of data used to analyze support for modularity hypotheses and the differing taxonomic levels of study. To test these hypotheses, we applied a comparative method to 3D geometric morphometric data collected from the skulls of a diverse order of birds (the Charadriiformes) to test support for 11 distinct hypotheses of modular skull evolution. Across all Charadriiformes, our analyses suggested that charadriiform skull evolution has been characterized by the semi-independent, but still correlated, evolution of the beak from the rest of the skull. When we adjusted the density of our morphometric data, this result held, but the strength of the signal varied substantially. Additionally, when we analyzed subgroups within the order in isolation, we found support for distinct hypotheses between subgroups. Taken together, these results suggest that differences in the methodology of past work (i.e., statistical method and data density) as well as clade-specific dynamics may be the reasons past studies have reached varying conclusions.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21703","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140891893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tradeoffs between bite force and gape in Eulemur and Varecia","authors":"Myra F. Laird,&nbsp;Taylor A. Polvadore,&nbsp;Gabrielle A. Hirschkorn,&nbsp;Julie C. McKinney,&nbsp;Callum F. Ross,&nbsp;Andrea B. Taylor,&nbsp;Claire E. Terhune,&nbsp;Jose Iriarte-Diaz","doi":"10.1002/jmor.21699","DOIUrl":"10.1002/jmor.21699","url":null,"abstract":"<p>In 1974, Sue Herring described the relationship between two important performance variables in the feeding system, bite force and gape. These variables are inversely related, such that, without specific muscular adaptations, most animals cannot produce high bite forces at large gapes for a given sized muscle. Despite the importance of these variables for feeding biomechanics and functional ecology, the paucity of in vivo bite force data in primates has led to bite forces largely being estimated through ex vivo methods. Here, we quantify and compare in vivo bite forces and gapes with output from simulated musculoskeletal models in two craniofacially distinct strepsirrhines: <i>Eulemur</i>, which has a shorter jaw and slower chewing cycle durations relative to jaw length and body mass compared to <i>Varecia</i>. Bite forces were collected across a range of linear gapes from 16 adult lemurs (suborder Strepsirrhini) at the Duke Lemur Center in Durham, North Carolina representing three species: <i>Eulemur flavifrons</i> (<i>n</i> = 6; 3F, 3M), <i>Varecia variegata</i> (<i>n</i> = 5; 3F, 2M), and <i>Varecia rubra</i> (<i>n</i> = 5; 5F). Maximum linear and angular gapes were significantly higher for <i>Varecia</i> compared to <i>Eulemur</i> (<i>p</i> = .01) but there were no significant differences in recorded maximum in vivo bite forces (<i>p</i> = .88). Simulated muscle models using architectural data for these taxa suggest this approach is an accurate method of estimating bite force-gape tradeoffs in addition to variables such as fiber length, fiber operating range, and gapes associated with maximum force. Our in vivo and modeling data suggest <i>Varecia</i> has reduced bite force capacities in favor of absolutely wider gapes compared to <i>Eulemur</i> in relation to their longer jaws. Importantly, our comparisons validate the simulated muscle approach for estimating bite force as a function of gape in extant and fossil primates.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21699","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140876602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An atlas of anatomical variants of the human calcaneus","authors":"Samuel James Cockerill,&nbsp;Matilde Arnay-de-la-Rosa,&nbsp;Emilio González-Reimers","doi":"10.1002/jmor.21706","DOIUrl":"https://doi.org/10.1002/jmor.21706","url":null,"abstract":"<p>The usefulness of anatomical variation is determined by the knowledge of why nonmetric traits appear. Clear descriptions of the traits are a necessary task, due to the risk of confusing anatomical variants and evidence of trauma. Numerous interpretations of the appearance of calcaneal anatomical variants add to the need of an anatomical atlas of calcaneal nonmetric traits. We have analyzed a total of 886 calcanei; 559 belong to different modern and pre-Hispanic samples, and 327 bones were studied from a reference collection from Athens. In this study, we present the anatomical variations that exist on the calcaneus bone, some of which have rarely been mentioned in previous research. The standardization of methods proposed may be useful to experts working in human anatomy, physical anthropology as well as comparative morphology, due to usefulness of this information during surgery, and bioanthropology to observe and study the lifestyle of past populations.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ontogenetic changes in jaw leverage and skull shape in tufted and untufted capuchins","authors":"Megan A. Holmes,&nbsp;Claire E. Terhune,&nbsp;Janine Chalk-Wilayto,&nbsp;Caitlin B. Yoakum,&nbsp;Parker Taylor,&nbsp;Rocio Ramirez,&nbsp;Megan P. Solís,&nbsp;Taylor A. Polvadore,&nbsp;Callum F. Ross,&nbsp;Andrea B. Taylor,&nbsp;Mariana Dutra Fogaca,&nbsp;Myra F. Laird","doi":"10.1002/jmor.21705","DOIUrl":"https://doi.org/10.1002/jmor.21705","url":null,"abstract":"<p>The ontogeny of feeding is characterized by shifting functional demands concurrent with changes in craniofacial anatomy; relationships between these factors will look different in primates with disparate feeding behaviors during development. This study examines the ontogeny of skull morphology and jaw leverage in tufted (<i>Sapajus</i>) and untufted (<i>Cebus</i>) capuchin monkeys. Unlike <i>Cebus</i>, <i>Sapajus</i> have a mechanically challenging diet and behavioral observations of juvenile <i>Sapajus</i> suggest these foods are exploited early in development. Landmarks were placed on three-dimensional surface models of an ontogenetic series of <i>Sapajus</i> and <i>Cebus</i> skulls (<i>n</i> = 53) and used to generate shape data and jaw-leverage estimates across the tooth row for three jaw-closing muscles (temporalis, masseter, medial pterygoid) as well as a weighted combined estimate. Using geometric morphometric methods, we found that skull shape diverges early and shape is significantly different between <i>Sapajus</i> and <i>Cebus</i> throughout ontogeny. Additionally, jaw leverage varies with age and position on the tooth row and is greater in <i>Sapajus</i> compared to <i>Cebus</i> when calculated at the permanent dentition. We used two-block partial least squares analyses to identify covariance between skull shape and each of our jaw muscle leverage estimates. <i>Sapajus</i>, but not <i>Cebus</i>, has significant covariance between all leverage estimates at the anterior dentition. Our findings show that <i>Sapajus</i> and <i>Cebus</i> exhibit distinct craniofacial morphologies early in ontogeny and strong covariance between leverage estimates and craniofacial shape in <i>Sapajus</i>. These results are consistent with prior behavioral and comparative work suggesting these differences are a function of selection for exploiting mechanically challenging foods in <i>Sapajus</i>, and further emphasize that these differences appear quite early in ontogeny. This research builds on prior work that has highlighted the importance of understanding ontogeny for interpreting adult morphology.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphological variation of tail bone among two chicken breeds and their F1 progeny","authors":"Prudence Nyirimana,&nbsp;Daisuke Kondoh,&nbsp;Jumpei Tomiyasu,&nbsp;Momoka Watanabe,&nbsp;Yume Okada,&nbsp;Yuma Nishida,&nbsp;Tatsuhiko Goto","doi":"10.1002/jmor.21704","DOIUrl":"https://doi.org/10.1002/jmor.21704","url":null,"abstract":"<p>Fancy breeds of Japanese indigenous chicken display extensive morphological diversity, particularly in tail feathers. Although marked differences in tail and bone traits have been reported between Tosa-jidori (wild type) and Minohikichabo (rich type) breeds, little is known about the pattern of genetic inheritance in cross experiments. Therefore, this study aimed to investigate the strain and sex effects, and inheritance patterns, in the morphometric variation of pygostyle bones among Tosa-jidori, Minohikichabo, and their F₁ hybrids. Five morphological traits, angle of the apex of the pygostyle, pygostyle length, margo cranialis length, tail feather number, and body weight, were evaluated at the adult stage. A significant strain difference was detected in all traits, whereas significant sex differences were observed in only three traits, but not in the angle of the apex of the pygostyle and tail feather number. In F₁ hybrids, the angle of the apex of the pygostyle was significantly different to that of Tosa-jidori but not that of Minohikichabo, whereas the pygostyle length and tail number of F₁ hybrids were significantly different from those of Minohikichabo but not those of Tosa-jidori. A significant heterosis effect was found in the margo cranialis length and body weight. All five traits showed nonadditive inheritance patterns but varied in each trait between partial dominance (angle of the apex of pygostyle), full dominance (pygostyle length and tail feather number), and over-dominance (margo cranialis length and body weight). Interestingly, different patterns of genetic inheritance in the F₁ hybrid were observed at different locations, even within the same pygostyle bone. Using the Japanese indigenous chicken model, these results provide a substantial step toward understanding the genetic architecture of morphology in chickens.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140826169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative finite element analysis of the first thoracic vertebra in artiodactyls","authors":"Sandra Schüler,&nbsp;Alana C. Sharp,&nbsp;John A. Nyakatura","doi":"10.1002/jmor.21695","DOIUrl":"https://doi.org/10.1002/jmor.21695","url":null,"abstract":"<p>Artiodactyls exhibit a striking diversity of the cervical vertebral column in terms of length and overall mobility. Using finite element analysis, this study explores the morphology at the cervico-thoracic boundary and its performance under loads in artiodactyls with different habitual neck postures and body sizes. The first thoracic vertebra of 36 species was loaded with (i) a compressive load on the vertebral body to model the weight of the head and neck exerted onto the trunk; and (ii) a tensile load at the spinous process to model the pull via the nuchal ligament. Additional focus was laid on the peculiar shape of the first thoracic vertebra in giraffes. We hypothesized that a habitually upright neck posture should be reflected in the greater ability to withstand compressive loads compared to tensile loads, whereas for species with a habitually suspended posture it should be the opposite. In comparison to species with a suspended posture, species with an upright posture exhibited lower stress (except Giraffidae). For compressive loads in larger species, stress surprisingly increased. Tensile loads in larger species resulted in decreased stress only in species with an intermediate or suspensory neck posture. High stress under tensile loads was mainly reflecting the relative length of the spinous process, while high stress under compressive loads was common in more “bell”-shaped vertebral bodies. The data supports a stability-mobility trade-off at the cervico-thoracic transition in giraffes. Performance under load at the cervico-thoracic boundary is indicative of habitual neck posture and is influenced by body size.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jmor.21695","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140818953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative skull osteology of Amphisbaena arda and Amphisbaena vermicularis (Squamata: Amphisbaenidae)","authors":"Carolina L. Paiva,&nbsp;Christy A. Hipsley,&nbsp;Johannes Müller,&nbsp;Hussam Zaher,&nbsp;Henrique C. Costa","doi":"10.1002/jmor.21702","DOIUrl":"https://doi.org/10.1002/jmor.21702","url":null,"abstract":"<p>The skull anatomy of amphisbaenians directly influences their capacity to burrow and is crucial for the study of their systematics, which ultimately contributes to our comprehension of their evolution and ecology. In this study, we employed three-dimensional X-ray computed tomography to provide a detailed description and comprehensive comparison of the skull anatomy of two amphisbaenian species with similar external morphology, <i>Amphisbaena arda</i> and <i>Amphisbaena vermicularis</i>. Our findings revealed some differences between the species, especially in the sagittal crest of the parietal bone, the ascendant process, and the transverse occipital crest of the occipital complex. We also found intraspecific variation within <i>A. vermicularis</i>, with some specimens displaying morphology that differed from their conspecifics but not from <i>A. arda</i>. The observed intraspecific variation within <i>A. vermicularis</i> cannot be attributed to soil features because all specimens came from the same locality. Specimen size and soil type may play a role in the observed differences between <i>A. arda</i> and <i>A. vermicularis</i>, as the single <i>A. arda</i> specimen is the largest of our sample and soil type and texture differ between the collection sites of the two species.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140818925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lectin binding to pectoral fin of neonate little skates reared under ambient and projected-end-of-century temperature regimes","authors":"Peyton Thomas,&nbsp;Emily E. Peele,&nbsp;Kara E. Yopak,&nbsp;James A. Sulikowski,&nbsp;Stephen T. Kinsey","doi":"10.1002/jmor.21698","DOIUrl":"https://doi.org/10.1002/jmor.21698","url":null,"abstract":"<p>The glycosylation of macromolecules can vary both among tissue structural components and by adverse conditions, potentially providing an alternative marker of stress in organisms. Lectins are proteins that bind carbohydrate moieties and lectin histochemistry is a common method to visualize microstructures in biological specimens and diagnose pathophysiological states in human tissues known to alter glycan profiles. However, this technique is not commonly used to assess broad-spectrum changes in cellular glycosylation in response to environmental stressors. In addition, the binding of various lectins has not been studied in elasmobranchs (sharks, skates, and rays). We surveyed the binding tissue structure specificity of 14 plant-derived lectins, using both immunoblotting and immunofluorescence, in the pectoral fins of neonate little skates (<i>Leucoraja erinacea</i>). Skates were reared under present-day or elevated (+5°C above ambient) temperature regimes and evaluated for lectin binding as an indicator of changing cellular glycosylation and tissue structure. Lectin labeling was highly tissue and microstructure specific. Dot blots revealed no significant changes in lectin binding between temperature regimes. In addition, lectins only detected in the elevated temperature treatment were <i>Canavalia ensiformis</i> lectin (Concanavalin A) in spindle cells of muscle and <i>Ricinus communis</i> agglutinin in muscle capillaries. These results provide a reference for lectin labeling in elasmobranch tissue that may aid future investigations.</p>","PeriodicalId":16528,"journal":{"name":"Journal of Morphology","volume":"285 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140651191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}