Body Shape (body + shape)

Distribution by Scientific Domains
Distribution within Life Sciences

Terms modified by Body Shape

  • body shape change

  • Selected Abstracts


    SEXUAL SELECTION, GENETIC ARCHITECTURE, AND THE CONDITION DEPENDENCE OF BODY SHAPE IN THE SEXUALLY DIMORPHIC FLY PROCHYLIZA XANTHOSTOMA (PIOPHILIDAE)

    EVOLUTION, Issue 1 2005
    Russell Bonduriansky
    Abstract The hypothesis that sexual selection drives the evolution of condition dependence is not firmly supported by empirical evidence, and the process remains poorly understood. First, even though sexual competition typically involves multiple traits, studies usually compare a single sexual trait with a single "control" trait, ignoring variation among sexual traits and raising the possibility of sampling bias. Second, few studies have addressed the genetic basis of condition dependence. Third, even though condition dependence is thought to result from a form of sex-specific epistasis, the evolution of condition dependence has never been considered in relation to intralocus sexual conflict. We argue that condition dependence may weaken intersexual genetic correlations and facilitate the evolution of sexual dimorphism. To address these questions, we manipulated an environmental factor affecting condition (larval diet) and examined its effects on four sexual and four nonsexual traits in Prochyliza xanthostoma adults. As predicted by theory, the strength of condition dependence increased with degree of exaggeration among male traits. Body shape was more condition dependent in males than in females and, perhaps as a result, genetic and environmental effects on body shape were congruent in males, but not in females. However, of the four male sexual traits, only head length was significantly larger in high-condition males after controlling for body size. Strong condition dependence was associated with reduced intersexual genetic correlation. However, homologous male and female traits exhibited correlated responses to condition, suggesting an intersexual genetic correlation for condition dependence itself. Our findings support the role of sexual selection in the evolution of condition dependence, but reveal considerable variation in condition dependence among sexual traits. It is not clear whether the evolution of condition dependence has mitigated or exacerbated intralocus sexual conflict in this species. [source]


    Hazardous Waist: How Body Shape Puts Health at Risk

    NURSING FOR WOMENS HEALTH, Issue 1 2007
    Susan J. Appel PhD
    First page of article [source]


    Size-dependent reproductive dominance in foundresses of Ropalidia plebeiana, an Australian paper wasp forming nest aggregations (Hymenoptera: Vespidae)

    ENTOMOLOGICAL SCIENCE, Issue 4 2003
    Hirokazu FUKUDA
    Abstract The relationship between reproductive status and body size in foundresses of Ropalidia plebeiana, an Australian endemic paper wasp forming huge aggregations of nests, was examined. Foundresses with developed ovaries (laying foundresses) in multifoundress colonies tended to be larger than foundresses in single-foundress colonies and foundresses with undeveloped ovaries (non-laying foundresses). However, the laying foundress was not always the largest of the foundresses in a colony. Body shape in foundresses varied according to simple allometric growth, while foundresses and first brood females diverged in their growth parameters in the preimaginal stage. [source]


    SEXUAL SELECTION, GENETIC ARCHITECTURE, AND THE CONDITION DEPENDENCE OF BODY SHAPE IN THE SEXUALLY DIMORPHIC FLY PROCHYLIZA XANTHOSTOMA (PIOPHILIDAE)

    EVOLUTION, Issue 1 2005
    Russell Bonduriansky
    Abstract The hypothesis that sexual selection drives the evolution of condition dependence is not firmly supported by empirical evidence, and the process remains poorly understood. First, even though sexual competition typically involves multiple traits, studies usually compare a single sexual trait with a single "control" trait, ignoring variation among sexual traits and raising the possibility of sampling bias. Second, few studies have addressed the genetic basis of condition dependence. Third, even though condition dependence is thought to result from a form of sex-specific epistasis, the evolution of condition dependence has never been considered in relation to intralocus sexual conflict. We argue that condition dependence may weaken intersexual genetic correlations and facilitate the evolution of sexual dimorphism. To address these questions, we manipulated an environmental factor affecting condition (larval diet) and examined its effects on four sexual and four nonsexual traits in Prochyliza xanthostoma adults. As predicted by theory, the strength of condition dependence increased with degree of exaggeration among male traits. Body shape was more condition dependent in males than in females and, perhaps as a result, genetic and environmental effects on body shape were congruent in males, but not in females. However, of the four male sexual traits, only head length was significantly larger in high-condition males after controlling for body size. Strong condition dependence was associated with reduced intersexual genetic correlation. However, homologous male and female traits exhibited correlated responses to condition, suggesting an intersexual genetic correlation for condition dependence itself. Our findings support the role of sexual selection in the evolution of condition dependence, but reveal considerable variation in condition dependence among sexual traits. It is not clear whether the evolution of condition dependence has mitigated or exacerbated intralocus sexual conflict in this species. [source]


    Growth in length and in body depth in young-of-the-year perch with different predation risk

    JOURNAL OF FISH BIOLOGY, Issue 3 2004
    C. Magnhagen
    Body shape of young-of-the-year (YOY) perch Perca fluviatilis, and number and size of potential predators (perch and pike Esox lucius) were compared across five lakes in northern Sweden. Body depth and dorsal fin ray length of YOY perch differed between lakes, with high relative body depth and long dorsal fin rays found in the lakes where the number of large piscivores was the highest. The most slender fish were found in the lake where the perch population had the smallest individuals and pike occurred in very low numbers. The average body mass in YOY perch from the two lakes with highest and lowest body depth, respectively, were the same, which indicates a difference between lakes in the relation between growth in length and in depth. Both body depth and fin ray length were correlated with predation risk by pike. Fin ray length was also correlated with number of piscivorous perch. Selection for different body shapes can be caused by different biotic and abiotic factors, singly or in combination, and the results from this study indicates that predation risk is one of these factors affecting body depth and fin ray length in perch. [source]


    SOMATOTYPING, ANTIMODERNISM, AND THE PRODUCTION OF CRIMINOLOGICAL KNOWLEDGE,

    CRIMINOLOGY, Issue 4 2007
    NICOLE RAFTER
    This study analyzes the work of William H. Sheldon, the psychologist, physician, and advocate of the study of body types. It investigates how he arrived at his much-repeated finding that a correlation exists between mesomorphy (a stocky, muscular body build) and delinquency and how his ideas were validated and perpetuated. It reviews what Sheldon actually said about the causes of crime; identifies his goals in searching for a relationship between body shape and criminality; explains how he found audiences for his biological theory at a time when sociological approaches dominated criminology; and attempts to understand the current criminological ambivalence about the scientific status of Sheldon's work, despite its discreditation decades ago. I argue that the tripartite structure of Sheldon's thought attracted three different audiences,methodologists, social scientists, and supporters,and that it encouraged the supporters to fund his research without reference to the critiques of the social scientists. I also argue that somatotyping was part of a broader antimodernist reaction within international scientific communities against the dislocations of twentieth-century life. To understand the origins, acceptance, and maintenance of criminological ideas, we need a historical perspective on figures of the past. Positivism may inform us about what is true and false, but we also need to know how truth and falsity have been constructed over time and how the ideas of earlier criminologists were shaped by their personal and social contexts. [source]


    On the morphology of Acanthostomum spiniceps (Looss, 1896) and A. absconditum (Looss, 1901) (Digenea: Cryptogonimidae: Acanthostominae) with particular reference to the juvenile stage

    ACTA ZOOLOGICA, Issue 3 2006
    Mohammed Hasan Ibraheem
    Abstract The morphology of juvenile and adult stages of Acanthostomum spiniceps and A. absconditum, from bagrid fish of the river Nile in Egypt, was studied with both light and scanning electron microscopy. In early juveniles, circumoral spines are absent and the entire body surface is covered with tegumental spines. Late juveniles show gradual differentiation of the circumoral tegument into a collar of spines associated with a reduction in density of tegumental spines at the posterior extremity of the body. Genital primordia appear when juveniles are about 1.75 mm long. The distributions of tegumental spines on adult A. spiniceps and A. absconditum are similar. Spines are denser on the dorsal and ventral surfaces of the anterior and middle parts of the body and less dense towards the posterior end. The tegumental fold surrounding the ventral sucker of A. absconditum has spines while the fold of A. spiniceps lacks them. The most important morphological features differentiating both species are the number of circumoral spines, body shape, ratio of body length to width, sucker sizes, and the presence or absence of spines on the ventral sucker. [source]


    Rapid morphological change in stream beetle museum specimens correlates with climate change

    ECOLOGICAL ENTOMOLOGY, Issue 5 2008
    JENNIFER BABIN-FENSKE
    Abstract 1.,Climate change has been occurring at unprecedented rates and its impacts on biological populations is beginning to be well documented in the literature. For many species, however, long-term records are not available, and trends have not been documented. 2.,Using museum specimens from southern USA, we show that the stream-dwelling beetle Gyretes sinuatus has shown an 8% increase in body size and change in body shape (fineness ratio) from 1928 to 1988. Any directional morphological change observed over time could be an indicator of a microevolutionary response. 3.,During these 60 years, there have also been changes in temperature, precipitation, and location of collection sites. Unlike the global trend, mean annual temperature in the region has decreased, and furthermore, total annual precipitation has increased. By investigating how these various ecological and geographical variables may affect body size and shape, we can examine which pressures may promote larger and/or thinner beetles. 4.,Results indicate that mean annual temperature was the most predictive variable for the change in size and shape. We suggest there is an adaptive role for temperature on body size and shape of stream dwelling organisms. 5.,We found that museum specimens can be invaluable resources of information when collection date and location information is available. We promote the use of such specimens for future studies of the morphological response to climate change. [source]


    Experiences of pregnancy-related body shape changes and of breast-feeding in women with a history of eating disorders

    EUROPEAN EATING DISORDERS REVIEW, Issue 2 2003
    Gunilla Larsson
    Abstract In spite of the growing problems of eating disorders in society, no publications have reported the cumulative prevalence of eating disorders among childbearing women. The condition may constitute a risk during pregnancy and the childbirth period. This study examined the frequency of self-reported eating disorder histories in women who had been delivered 3,7 months earlier as well as their experiences of body shape changes and breast feeding and the length of the breast-feeding periods. Five hundred and sixteen women were invited to participate, of whom 454 responded to a questionnaire (88 per cent). A history of an eating disorder was reported by 11.5 per cent of the respondents, with a predominance of younger women. Significantly fewer women among those reporting an eating disorder breast-fed their 3-month-old baby. However, no difference was seen regarding feelings related to the transformed body shape. Almost all women described such feelings as positive. Copyright © 2003 John Wiley & Sons, Ltd and Eating Disorders Association. [source]


    ECOLOGICAL SPECIATION IN GAMBUSIA FISHES

    EVOLUTION, Issue 9 2007
    R. Brian Langerhans
    Although theory indicates that natural selection can facilitate speciation as a by-product, demonstrating ongoing speciation via this by-product mechanism in nature has proven difficult. We examined morphological, molecular, and behavioral data to investigate ecology's role in incipient speciation for a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes. We show that adaptation to divergent predator regimes is driving ecological speciation as a by-product. Divergence in body shape, coupled with assortative mating for body shape, produces reproductive isolation that is twice as strong between populations inhabiting different predator regimes than between populations that evolved in similar ecological environments. Gathering analogous data on reproductive isolation at the interspecific level in the genus, we find that this mechanism of speciation may have been historically prevalent in Gambusia. These results suggest that speciation in nature can result as a by-product of divergence in ecologically important traits, producing interspecific patterns that persist long after speciation events have completed. [source]


    CONVERGENCE AND THE MULTIDIMENSIONAL NICHE

    EVOLUTION, Issue 2 2005
    Luke J. Harmon
    Abstract Convergent evolution has played an important role in the development of the ecological niche concept. We investigated patterns of convergent and divergent evolution of Caribbean Anolis lizards. These lizards diversified independently on each of the islands of the Greater Antilles, producing the same set of habitat specialists on each island. Using a phylogenetic comparative framework, we examined patterns of morphological convergence in five functionally distinct sets of morphological characters: body size, body shape, head shape, lamella number, and sexual size dimorphism. We find evidence for convergence among members of the habitat specialist types for each of these five datasets. Furthermore, the patterns of convergence differ among at least four of the five datasets; habitat specialists that are similar for one set of characters are often greatly different for another. This suggests that the habitat specialist niches into which these anoles have evolved are multidimensional, involving several distinct and independent aspects of morphology. [source]


    SEXUAL SELECTION, GENETIC ARCHITECTURE, AND THE CONDITION DEPENDENCE OF BODY SHAPE IN THE SEXUALLY DIMORPHIC FLY PROCHYLIZA XANTHOSTOMA (PIOPHILIDAE)

    EVOLUTION, Issue 1 2005
    Russell Bonduriansky
    Abstract The hypothesis that sexual selection drives the evolution of condition dependence is not firmly supported by empirical evidence, and the process remains poorly understood. First, even though sexual competition typically involves multiple traits, studies usually compare a single sexual trait with a single "control" trait, ignoring variation among sexual traits and raising the possibility of sampling bias. Second, few studies have addressed the genetic basis of condition dependence. Third, even though condition dependence is thought to result from a form of sex-specific epistasis, the evolution of condition dependence has never been considered in relation to intralocus sexual conflict. We argue that condition dependence may weaken intersexual genetic correlations and facilitate the evolution of sexual dimorphism. To address these questions, we manipulated an environmental factor affecting condition (larval diet) and examined its effects on four sexual and four nonsexual traits in Prochyliza xanthostoma adults. As predicted by theory, the strength of condition dependence increased with degree of exaggeration among male traits. Body shape was more condition dependent in males than in females and, perhaps as a result, genetic and environmental effects on body shape were congruent in males, but not in females. However, of the four male sexual traits, only head length was significantly larger in high-condition males after controlling for body size. Strong condition dependence was associated with reduced intersexual genetic correlation. However, homologous male and female traits exhibited correlated responses to condition, suggesting an intersexual genetic correlation for condition dependence itself. Our findings support the role of sexual selection in the evolution of condition dependence, but reveal considerable variation in condition dependence among sexual traits. It is not clear whether the evolution of condition dependence has mitigated or exacerbated intralocus sexual conflict in this species. [source]


    EMPIRICAL EVIDENCE FOR AN OPTIMAL BODY SIZE IN SNAKES

    EVOLUTION, Issue 2 2003
    Scott M. Boback
    Abstract The concept of optimal size has been invoked to explain patterns in body size of terrestrial mammals. However, the generality of this phenomenon has not been tested with similarly complete data from other taxonomic groups. In this study we describe three statistical patterns of body size in snakes, all of which indicate an optimal length of 1.0 m. First, a distribution of largest body lengths of 618 snake species had a single mode at 1.0 m. Second, we found a positive relationship between the size of the largest member of an island snake assemblage and island area and a negative relationship between the size of the smallest member of an island snake assemblage and island area. Best-fit lines through these data cross at a point corresponding to 1.0 m in body length, the presumed optimal size for a one-species island. Third, mainland snake species smaller than 1.0 m become larger on islands whereas those larger than 1.0 m become smaller on islands. The observation that all three analyses converge on a common body size is concordant with patterns observed in mammals and partial analyses of four other disparate animal clades. Because snakes differ so strikingly from mammals (ectotherms, gape-limited predators, elongate body shape) the concordant patterns of these two groups provide strong evidence for the evolution of an optimal body size within independent monophyletic groups. However, snakes differ from other taxonomic groups that have been studied in exhibiting a body size distribution that is not obviously skewed in either direction. We suggest that idiosyncratic features of the natural history of ectotherms allow relatively unconstrained distributions of body size whereas physiological limitations of endotherms constrain distributions of body size to a right skew. [source]


    SPATIOTEMPORAL REORGANIZATION OF GROWTH RATES IN THE EVOLUTION OF ONTOGENY

    EVOLUTION, Issue 4 2000
    Miriam L. Zelditch
    Abstract. Heterochrony, evolutionary changes in rate or timing of development producing parallelism between ontogeny and phylogeny, is viewed as the most common type of evolutionary change in development. Alternative hypotheses such as heterotopy, evolutionary change in the spatial patterning of development, are rarely entertained. We examine the evidence for heterochrony and heterotopy in the evolution of body shape in two clades of piranhas. One of these is the sole case of heterochrony previously reported in the group; the others were previously interpreted as cases of heterotopy. To compare ontogenies of shape, we computed ontogenetic trajectories of shape by multivariate regression of geometric shape variables (i.e., partial warp scores and shape coordinates) on centroid size. Rates of development relative to developmental age and angles between the trajectories were compared statistically. We found a significant difference in developmental rate between species of Serrasalmus, suggesting that heterochrony is a partial explanation for the evolution of body shape, but we also found a significant difference between their ontogenetic transformations; the direction of the difference between them suggests that heterotopy also plays a role in this group. In Pygocentrus we found no difference in developmental rate among species, but we did find a difference in the ontogenies, suggesting that heterotopy, but not heterochrony, is the developmental basis for shape diversification in this group. The prevalence of heterotopy as a source of evolutionary novelty remains largely unexplored and will not become clear until the search for developmental explanations looks beyond heterochrony. [source]


    A new body mass estimation of Brachiosaurus brancai Janensch, 1914 mounted and exhibited at the Museum of Natural History (Berlin, Germany)

    FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 1 2008
    Hanns-Christian Gunga
    Abstract Body mass and surface areas are important in several aspects for an organism living today. Therefore, mass and surface determinations for extinct dinosaurs could be important for paleo-biological aspects as well. Based on photogrammetrical measurement the body mass and body surface area of the Late Jurassic Brachiosaurus brancai Janensch, 1914 from Tendaguru (East Africa), a skeleton mounted and exhibited at the Museum of Natural History in Berlin (Germany), has been re-evaluated. We determined for a slim type of 3D reconstruction of Brachiosaurus brancai a total volume of 47.9 m3 which represents, assuming a mean tissue density of 0.8 kg per 1,000 cm3, a total body mass of 38,000 kg. The volume distributions from the head to the tail were as follows: 0.2 m3 for the head, neck 7.3 m3, fore limbs 2.9 m3, hind limbs 2.6 m3, thoracic-abdominal cavity 32.4 m3, tail 2.2 m3. The total body surface area was calculated to be 119.1 m2, specifically 1.5 m2 for the head, 26 m2 neck, fore limbs 18.8 m2, hind limbs 16.4 m2, 44.2 m2 thoracic-abdominal cavity, and finally the tail 12.2 m2. Finally, allometric equations were used to estimate presumable organ sizes of this extinct dinosaur and to test whether their dimensions really fit into the thoracic and abdominal cavity of Brachiosaurus brancai if a slim body shape of this sauropod is assumed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Classification of upper lateral body shapes for the apparel industry

    HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 5 2010
    Young Lim Choi
    Abstract The lateral body shape is a critical determiner of the fit of garments. Either visual assessment or statistical analysis methods have been used to classify the lateral body types. These methods are limited to some extent since various anthropometric features inherently coexist and interact in a human body shape. This study aims to develop objective criteria for the classification of upper lateral body shapes integrating visual assessment and statistical analysis. The three-dimensional scan data of 246 women between 18 and 49 years old were visually classified into four lateral body shapes by an expert panel. In addition, the back space and lateral angles extracted from the scan data were employed for further statistical analyses. Multinomial logistic regressions were used to develop logit models for lateral body types. It was concluded that the resulting logit models could classify lateral body types and calculate the probability of a set of body scan data being classified as a certain lateral body type. It is expected that this probability might be a guideline to quantify the characteristics of the lateral body shape in the apparel industry. © 2010 Wiley Periodicals, Inc. [source]


    Anorexia nervosa and gender identity disorder in biologic males: A report of two cases

    INTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 1 2004
    Anthony P. Winston
    Abstract Gender identity disorder is a rare disorder of uncertain etiology. The emphasis on body shape in this disorder suggests that there may be an association with anorexia nervosa. Method We report two cases of anorexia nervosa and gender identity disorder in biologic males who presented to an eating disorders service. Results One was treated successfully as an outpatient and subsequently underwent gender reassignment surgery. The other patient required admission and prolonged psychotherapy. Discussion Differences between the two cases are discussed. Issues of gender identity should be considered in the assessment of male patients presenting with anorexia nervosa. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 109,113, 2004. [source]


    The nature of body image disturbance in patients with binge eating disorder

    INTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2003
    Robin M. Masheb
    Abstract Objective This study examined the distinction between body dissatisfaction and self-evaluation unduly influenced by body shape and weight, and their longitudinal relationships to depressive symptomatology and self-esteem in patients with binge eating disorder (BED). Method Ninety-seven patients with BED completed measures tapping these constructs at baseline and again 4 weeks later. Results Change in body dissatisfaction was significantly correlated with both change in depressive symptomatology and change in self-esteem over time, whereas change in self-evaluation was significantly correlated only with change in self-esteem. In addition, change in shape concern, but not change in weight concern, was significantly correlated with change in self-esteem only. Discussion These findings suggest that self-evaluation unduly influenced by body shape is a more useful indicator for BED than body dissatisfaction or self-evaluation unduly influenced by weight. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 33: 333,341, 2003. [source]


    Jordan's and other ecogeographical rules, and the vertebral number in fishes

    JOURNAL OF BIOGEOGRAPHY, Issue 3 2008
    R. M. McDowall
    Abstract Aim, To explore variation in the number of vertebrae in fishes in the context of Jordan's rule and other ecogeographical rules. Location, Global. Methods, The study is based on literature review. Results, The number of vertebrae varies very widely across the diversity of fishes. Jordan's rule states that vertebral number increases with latitude, and this is widely attributed to ambient temperatures during ontogeny of individual fishes. However, the number of vertebrae may depend on both the ontogenetic environment and inheritance. Diverse other aspects of fish development and ecology are suggested as influencing vertebral number, including fish size, phyletic position, body shape and swimming mode. Main conclusions, The number of different factors that influence the number of vertebrae in fishes makes for highly complex patterns of variation, and means that unravelling causes is difficult. The question needs to be addressed at the population/species/species group scale; moreover, the lack of discrimination between environmental and inherited causes of variation adds to the complexity. [source]


    Heritability of life-history tactics and genetic correlation with body size in a natural population of brook charr (Salvelinus fontinalis)

    JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2007
    V. THÉRIAULT
    Abstract A common dimorphism in life-history tactic in salmonids is the presence of an anadromous pathway involving a migration to sea followed by a freshwater reproduction, along with an entirely freshwater resident tactic. Although common, the genetic and environmental influence on the adoption of a particular life-history tactic has rarely been studied under natural conditions. Here, we used sibship-reconstruction based on microsatellite data and an ,animal model' approach to estimate the additive genetic basis of the life-history tactic adopted (anadromy vs. residency) in a natural population of brook charr, Salvelinus fontinalis. We also assess its genetic correlation with phenotypic correlated traits, body size and body shape. Significant heritability was observed for life-history tactic (varying from 0.52 to 0.56 depending on the pedigree scenario adopted) as well as for body size (from 0.44 to 0.50). There was also a significant genetic correlation between these two traits, whereby anadromous fish were genetically associated with bigger size at age 1 (rG = ,0.52 and ,0.61). Our findings thus indicate that life-history tactics in this population have the potential to evolve in response to selection acting on the tactic itself or indirectly via selection on body size. This study is one of the very few to have successfully used sibship-reconstruction to estimate quantitative genetic parameters under wild conditions. [source]


    The role of predation in variation in body shape in guppies Poecilia reticulata: a comparison of field and common garden phenotypes

    JOURNAL OF FISH BIOLOGY, Issue 6 2009
    J. G. Burns
    The body shapes of both wild-caught and laboratory-reared male and female Trinidadian guppies Poecilia reticulata from two low-predation and two high-predation populations were studied, but predation regime did not seem to be the most important factor affecting body shape. Instead, complicated patterns of plasticity in body shape among populations and the sexes were found. In particular, populations differed in the depth of the caudal peduncle, which is the muscular region just anterior to the tail fin rays and from which most swimming power is generated. Strikingly, the direction of population differences in caudal peduncle depth observed in wild-caught individuals was reversed when P. reticulata were raised in a common laboratory environment. [source]


    Reduced swimming abilities in fast-growing transgenic common carp Cyprinus carpio associated with their morphological variations

    JOURNAL OF FISH BIOLOGY, Issue 1 2009
    D. Li
    Critical swimming speeds (Ucrit) and morphological characters were compared between the F4 generation of GH-transgenic common carp Cyprinus carpio and the non-transgenic controls. Transgenic fish displayed a mean absolute Ucrit value 22·3% lower than the controls. Principal component analysis identified variations in body shape, with transgenic fish having significantly deeper head, longer caudal length of the dorsal region, longer standard length (LS) and shallower body and caudal region, and shorter caudal length of the ventral region. Swimming speeds were related to the combination of deeper body and caudal region, longer caudal length of the ventral region, shallower head depth, shorter caudal length of dorsal region and LS. These findings suggest that morphological variations which are poorly suited to produce maximum thrust and minimum drag in GH-transgenic C. carpio may be responsible for their lower swimming abilities in comparison with non-transgenic controls. [source]


    About the oldest domesticates among fishes

    JOURNAL OF FISH BIOLOGY, Issue 2004
    E. K. Balon
    Domestication of mammals such as cattle, dogs, pigs and horses preceded that of fishes by at least 10 000 years. The first domesticated fish was the common carp Cyprinus carpio. Initially it was held as an exploited captive and did not undergo major changes in body shape or colour variations. About 2000 years ago, wild common carp were most abundant in the inland delta of the Danube River. These fish were torpedo shaped, golden-yellow in colour and had two pairs of barbels and a mesh-like scale pattern. Large schools of them thrived and reproduced on the flood plains of the Danube. The Romans kept fishes in specially built ponds at that time. The common carp was an ideal candidate and its rearing became more popular in medieval times. Common carp culture gradually became the most profitable branch of agriculture in central Europe and many special ponds were built. Soon common carp were being produced in pond systems including spawning and growing ponds. Unintentional artificial selection had taken place between the 12th and mid-14th century, and deep bodied and variously scaled or scaleless domesticated forms appeared in nearly every pond system. Some colour aberrations appeared in the 1950s in Japan, which, as koi, became the most expensive of fish. Common carp were not originally domesticated in China but wild ,chi'Carassius auratus occasionally appeared as a xanthic form that, as the goldfish, has been known since 960 A.D. By the 1200s the fish were used as ornamental animals in the garden pools of rich landowners. Circa 1276 to 1546, the Chinese began keeping golden chi in aquarium-like vessels and soon rich and poor alike became breeders of the fancy domesticated goldfish. The variously shaped monstrosities and colour aberrants were freaks but they became very fashionable at that time and still are. Domesticated goldfish monstrosities were first exported from China to Japan and much later to Europe and around the world. More recently other species have been domesticated by aquarists, such as the guppy Poecilia reticulata or the neon tetra Paracheirodon innesi. Other fishes kept as ornamentals, like swordtails Xiphophorus hellerii and platies Xiphophorus maculatus, the discus and angelfishes (Cichlidae), as well as those cultured for food like the rainbow trout Oncorhynchus mykiss, channel catfish Ictalurus punctatus or sturgeons (Acipenseridae) are merely exploited captives. [source]


    Fish functional design and swimming performance

    JOURNAL OF FISH BIOLOGY, Issue 5 2004
    R. W. Blake
    Classifications of fish swimming are reviewed as a prelude to discussing functional design and performance in an ecological context. Webb (1984a, 1998) classified fishes based on body shape and locomotor mode into three basic categories: body and caudal fin (BCF) periodic, BCF transient (fast-starts, turns) and median and paired fin (MPF) swimmers. Swimming performance and functional design is discussed for each of these categories. Webb hypothesized that specialization in any given category would limit performance in any other. For example, routine MPF swimmers should be penalized in BCF transient (fast-start propulsion). Recent studies offer much support for Webb's construct but also suggest some necessary amendments. In particular, design and performance compromises for different swimming modes are associated with fish that employ the same propulsor for more than one task (coupled, e.g. the same propulsor for routine steady swimming and fast-starts). For example, pike (BCF transient specialist) achieve better acceleration performance than trout (generalist). Pike steady (BCF periodic) performance, however, is inferior to that of trout. Fish that employ different propulsors for different tasks (decoupled, e.g. MPF propulsion for low-speed routine swimming and BCF motions for fast-starts) do not show serious performance compromises. For example, certain MPF low-speed swimmers show comparable fast-start performance to BCF forms. Arguably, the evolution of decoupled locomotor systems was a major factor underlying the adaptive radiation of teleosts. Low-speed routine propulsion releases MPF swimmers from the morphological constraints imposed by streamlining allowing for a high degree of variability in form. This contrasts with BCF periodic swimming specialists where representatives of four vertebrate classes show evolutionary convergence on a single, optimal ,thunniform' design. However, recent experimental studies on the comparative performance of carangiform and thunniform swimmers contradict some of the predictions of hydromechanical models. This is addressed in regard to the swimming performance, energetics and muscle physiology of tuna. The concept of gait is reviewed in the context of coupled and decoupled locomotor systems. Biomimetic approaches to the development of Autonomous Underwater Vehicles have given a new context and impetus to research and this is discussed in relation to current views of fish functional design and swimming performance. Suggestions are made for possible future research directions. [source]


    Morphological variability in the Cuatro Cienegas cichlid, Cichlasoma minckleyi

    JOURNAL OF FISH BIOLOGY, Issue 2 2003
    J. Trapani
    The endemic cichlids of the Cuatro Cienegas Basin, Coahuila, Mexico are currently grouped in a single polymorphic species, Cichlasoma minckleyi. Two morphs of C. minckleyi were distinguished largely by features of the trophic apparatus, especially the pharyngeal dentition. Variation in body shape, based upon analysis of a set of linear measures, was continuous and did not allow recognition of discrete morphs. Individuals raised in the laboratory on several different diets indicated that trophic morphology had an important genetic component. Individuals raised in the laboratory, however, did not differentiate to the degree seen in comparably sized individuals collected at Cuatro Cienegas. This may be because snails used as food in the experiments were not as hard as endemic snails and indicated that some aspects of trophic morphology were also dependent upon environmental cues. [source]


    A11. The influence of the media on eating disorders

    JOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2000
    S. Almond
    Background The cause of eating disorders is multifactorial. One of these is sociocultural factors which include family, peers and the media. It has been suggested that constant media pressures can lead to body dissatisfaction, which may result in distorted eating patterns. Aims To review the role of the media in relation to eating disorders Results There has been a shift in the media portrayal of the 'ideal' body size for women, from the voluptuous curved figure of Marilyn Monroe in the 1950s to a thinner 'waif-like' look of Kate Moss in the 1980s. In the mass media shape and weight define perfection. Women perceive themselves as being bigger than they actually are. Their figure deviates from the ideal thus resulting in self body dissatisfaction. 'All I see is these pretty models, I wish I could look like one of them.' ( Wertheim et al. 1997 ) The 'ideal' body image is far from the physiologic norm. Supermodels are born with a specific body type and what the public doesn't understand is that they cannot diet to achieve it. 'Women don't set out to be anorexic, they begin by thinking they're too fat because everywhere they go the media is telling them that they are right' ( Barrett, 1997) Products are often advertised displaying the ideal body shape in the hope that it will enhance the product and create body dissatisfaction. Purchasing the product is perceived as a positive step towards reaching the 'perfect' body image. Concern surrounds the appearance of such advertisements in magazines aimed at adolescent girls, as at this age they are particularly vulnerable to the influences of the media. Stice and Shaw (1994) stated that exposure to the thin 'idea' may have a negative effect on emotions leading to body dissatisfaction. Such emotions include depression, stress, guilt, shame, insecurity, unhappiness, and lower self-confidence. A study by Schotte et al. (1990) indicated that negative emotions can disrupt eating behaviour. Dieters watching a frightening film increased their food intake, whereas nondieters did not. Conclusion The media are not solely responsible for eating disorders but they do contribute by promoting the 'ideal' physique. There is some resistance to media messages, as the majority of people do not develop distorted eating patterns. [source]


    An epidemiological study of environmental factors associated with canine obesity

    JOURNAL OF SMALL ANIMAL PRACTICE, Issue 7 2010
    E. A. Courcier
    Objectives: To assess the relationships between socioeconomic and other environmental factors with canine obesity. Methods: This was a cross-sectional questionnaire study of dog owners attending five primary veterinary practices in the UK. Owners were asked about dog age, neuter status, feeding habits, dog exercise, household income and owner age. The body condition score of the dogs was also assessed. Factors hypothesised to be associated with obesity were investigated. Results: In total, data from 696 questionnaires were evaluated. Out of those data evaluated, 35·3% of dogs (n=246) were classed as an ideal body shape, 38·9% (n=271) were overweight, 20·4% (n=142) were obese and 5·3% (n=37) were underweight. Identified risk factors associated with obesity included owner age, hours of weekly exercise, frequency of snacks/treats and personal income. Clinical Significance: Environmental risk factors associated with canine obesity are multifactorial and include personal income, owner age, frequency of snacks/treats and amount of exercise the dog receives. Awareness about health risks associated with obesity in dogs is significantly less in people in lower income brackets. This phenomenon is recognised in human obesity. [source]


    Phenotypic plasticity of anuran larvae: environmental variables influence body shape and oral morphology in Rana temporaria tadpoles

    JOURNAL OF ZOOLOGY, Issue 2 2002
    Miguel Vences
    Abstract Environmental variables shaped the morphology of tadpoles of the common frog, Rana temporaria, in various ways at the Pyrenean locality Circo de Piedrafita. Examining only specimens in similar developmental stages, those from small ponds (with higher temperature and higher tadpole density) had lower growth rates, lower relative tail height, lower relative body width and fewer labial keratodonts and keratodont rows. The variation in keratodonts may have been caused by heterochrony related to the slower growth rate. The number of lingual papillae also differed between ponds but was not related to pond size. Higher predator densities caused a higher percentage of damaged tails and a lower relative tail length in specimens with apparently intact tails, probably as a result of incomplete regeneration after mutilations earlier in development. [source]


    Differential admixture shapes morphological variation among invasive populations of the lizard Anolis sagrei

    MOLECULAR ECOLOGY, Issue 8 2007
    JASON J. KOLBE
    Abstract The biological invasion of the lizard Anolis sagrei provides an opportunity to study evolutionary mechanisms that produce morphological differentiation among non-native populations. Because the A. sagrei invasion represents multiple native-range source populations, differential admixture as well as random genetic drift and natural selection, could shape morphological evolution during the invasion. Mitochondrial DNA (mtDNA) analyses reveal seven distinct native-range source populations for 10 introduced A. sagrei populations from Florida, Louisiana and Texas (USA), and Grand Cayman, with 2,5 native-range sources contributing to each non-native population. These introduced populations differ significantly in frequencies of haplotypes from different native-range sources and in body size, toepad-lamella number, and body shape. Variation among introduced populations for both lamella number and body shape is explained by differential admixture of various source populations; mean morphological values of introduced populations are correlated with the relative genetic contributions from different native-range source populations. The number of source populations contributing to an introduced population correlates with body size, which appears independent of the relative contributions of particular source populations. Thus, differential admixture of various native-range source populations explains morphological differences among introduced A. sagrei populations. Morphological differentiation among populations is compatible with the hypothesis of selective neutrality, although we are unable to test the hypothesis of interdemic selection among introductions from different native-range source populations. [source]


    Identification and Treatment in Obstetrical Patients

    NURSING FOR WOMENS HEALTH, Issue 6 2006
    Lesa L.K. Chizawsky RN
    Eating disorders are well defined in females ages 14 to 24, and consist primarily of anorexia nervosa (AN) and bulimia nervosa (BN). Collectively, these two eating disorders are characterized by severe disturbances in eating behaviors and acute distress over body shape and weight. In AN, fear of weight gain coupled with a distorted body image leads to refusal to maintain a minimally accepted body weight (American Psychiatric Association [APA], 1994). Although women with BN also overvalue body size and shape, this disorder is characterized by episodes of binge eating followed by efforts to undo the binge episode (oral purging is the most widely known effort) (APA, 1994). Developmental, psychological, socioenvironmental and behavioral factors contribute to the complex development and persistence of AN and BN (Rosen & Neumark-Sztainer, 1998). [source]