Predictor Of Body Size Research Articles

Subterranean rodents of the genusCtenomys(Caviomorpha, Ctenomyidae) follow the converse to Bergmann's rule

AbstractAim We analysed body‐size variation in relation to latitude, longitude, elevation and environmental variables inCtenomys(tuco‐tucos), subterranean rodents in the Ctenomyidae (Caviomorpha). We tested the existence of inter‐ and intraspecific size clines to determine if these rodents follow Bergmann's rule, to compare intra‐ and interspecific size trends and to assess the relevance of the subterranean lifestyle on these trends.Location South America, south of 15° latitude.Methods This paper is based on 719 specimens of tuco‐tucos from 133 localities of Argentina, Bolivia, Chile, Paraguay, Peru and Uruguay, representing 47 named species and 32 undescribed forms. Intraspecific analyses were performed forCtenomys talarumThomas, 1898 and theCtenomys perrensiThomas, 1896 species complex. Head and body length and weight were used for estimating body size. Geographical independent variables included latitude, longitude and altitude. Environmental independent variables were mean minimal and maximal monthly temperature, mean annual temperature, mean minimal and maximal precipitation, and total annual precipitation. To estimate seasonality, the annual variability of the climatic factors was calculated as their coefficients of variation and the difference between maximum and minimum values. Mean annual actual evapotranspiration (AET), and mean annual, January (summer) and July (winter) potential evapotranspiration (PET) values were also calculated for each locality, as well as annual, summer and winter water balance (WB). Statistical analyses consisted of simple and multiple regression and nonparametric correlation.Results Body size ofCtenomysdecreases interspecifically from 15°00′ S to 48°15′ S and from 56°33′ W to 71°46′ W, and is positively correlated with ambient temperature and precipitation. The best predictors of body size according to multiple regression analyses were mean annual temperature, the difference between mean maximum and minimum annual temperatures, annual PET, the difference between summer and winter PET, and annual and winter water balance. These patterns are repeated, but not identically, at a smaller geographical scale within the speciesC. talarumand the superspeciesC. perrensi.Main conclusions Tuco‐tucos follow the converse to Bergmann's rule at the interspecific level. At the intraspecific level some parallel trends were observed, but the smaller scale of these analyses, involving a very reduced variation of environmental factors, necessitates caution in interpreting results. The subterranean lifestyle probably insulates these rodents from the external temperature. The observed latitudinal body‐size gradients are more probably related to seasonality, ambient energy, primary productivity and/or intensity of predation.

Female-specific color is a signal of quality in the striped plateau lizard (Sceloporus virgatus)

Recent theoretical and empirical studies confirm that male mate choice and/or female--female mate competition can be expressed in the absence of sex-role reversal. Such reproductive patterns may select for the evolution of female traits that indicate female phenotypic or genotypic quality among non--role-reversed species. Although attention to the evolution and function of female ornaments is increasing, additional focus is needed on female-specific ornaments (those not expressed in conspecific males) and on nonavian systems in order to gain a broad understanding of how selection acts directly on ornamentation of female animals. In the striped plateau lizard, Sceloporus virgatus, only females develop orange throat patches during the reproductive season. The color peaks in expression near the time of ovulation and appears to stimulate male courtship. Here, I examine whether this female-specific ornament can be used by males to reliably assess female phenotypic quality. Using multivariate regression analyses, I show that the area of the orange color patch predicts body condition and mite load, the chroma (i.e., saturation) of the color patch predicts body size, and both patch area and chroma reliably predict average egg mass. Thus, female reproductive color may function as a condition-dependent signal, indicating phenotypic quality to potential mates. Copyright 2006.

Regression analysis between body and head measurements of Chinese alligators (Alligator sinensis) in the captive population

Four body-size and fourteen head-size measurements were taken from each Chinese alligator (Alligator sinensis) according to the measurements adapted from Verdade. Regression equations between body-size and head-size variables were presented to predict body size from head dimension. The coefficients of determination of captive animals concerning body- and head-size variables can be considered extremely high, which means most of the head-size variables studied can be useful for predicting body length. The result of multivariate allometric analysis indicated that the head elongates as in most other species of crocodilians. The allometric coefficients of snout length (SL) and lower ramus (LM) were greater than those of other variables of head, which was considered to be possibly correlated to fights and prey. On the contrary, allometric coefficients for the variables of obita (OW, OL) and postorbital cranial roof (LCR), were lower than those of other variables.

Evolution of body size in the genusDamaliscus: a comparison with hartebeestAlcelaphusspp.

AbstractIn species with low levels of sexual size dimorphism, it may be relatively easy to detect the role of natural selection in the evolution of body size. Habitat primary production (HPP) appears to be a key factor in the divergence of size in the hartebeest clade (Alcelaphusspp.), such that subspecies in less productive savannahs are smaller than those in richer ones. Here I test whether a similar pattern exists within the genusDamaliscus(topi and their allies). Basal skull length was used as a surrogate of body size and measured in the seven allopatric subspecies ofDamaliscus. Means for each subspecies and sex were regressed against climatic factors as surrogates of HPP. Variation in skull length acrossDamaliscustaxa was less than in hartebeest. Two clusters were present in both sexes and corresponded to the distinction between the species,Damaliscus dorcasandDamaliscus lunatus. This may reflect differences in productivity between edaphic grasslands, occupied by allD. lunatus, and dry grasslands, occupied byD. dorcas. Mean annual rainfall was the best predictor of body size in males and showed a non‐significant positive tendency in females. After accounting for phylogenetic effects, these correlations were both non‐significant. Edaphic grasslands might be less dependent on precipitation for primary production because the impeded drainage of their soil prolongs water availability after the end of the rains. Furthermore, they are probably more consistent in productivity across African regions than secondary grasslands and savannah woodlands, which rely on rainfall for grass growth. These properties of edaphic grasslands may explain why size inDamaliscusappears to be less sensitive to variation in rainfall and less variable across subspecies than inAlcelaphus.

Geographic Variation in Somatic Growth of Redside Shiner

AbstractThe geographic variation in growth rate and resulting body size is poorly known for most fish species. In this paper, we used data derived from otoliths to describe patterns of growth in redside shiners Richardsonius balteatus from seven native populations across the southern portion of its range, and we compare growth with latitude, elevation, and growing season to determine which of these environmental factors best predicts the growth patterns among these populations. To determine whether observed differences in growth resulted from environmental or genetic variation, we conducted a common‐environment experiment on fish from three of the seven populations that showed contrasting patterns between latitude and length of growing season. Redside shiners exhibited about a 60% difference in size at age among populations in their natural environments. Growing season length was the best predictor of body size among these populations (Akaike weight = 0.78). In a common environment, temperature‐specific growth rates differed among populations, indicating that some of the observed differences in size at age among populations are genetically based. Although populations of redside shiners with shorter growing seasons exhibited higher field growth rates than expected, the pattern of variation in individual growth rates among populations in a common environment was not consistent with either a countergradient variation model or a local adaptation model of growth.

A quantitative analysis of the mechanism that controls body size in Manduca sexta

BackgroundBody size is controlled by mechanisms that terminate growth when the individual reaches a species-specific size. In insects, it is a pulse of ecdysone at the end of larval life that causes the larva to stop feeding and growing and initiate metamorphosis. Body size is a quantitative trait, so it is important that the problem of control of body size be analyzed quantitatively. The processes that control the timing of ecdysone secretion in larvae of the moth Manduca sexta are sufficiently well understood that they can be described in a rigorous manner.ResultsWe develop a quantitative description of the empirical data on body size determination that accurately predicts body size for diverse genetic strains. We show that body size is fully determined by three fundamental parameters: the growth rate, the critical weight (which signals the initiation of juvenile hormone breakdown), and the interval between the critical weight and the secretion of ecdysone. All three parameters are easily measured and differ between genetic strains and environmental conditions. The mathematical description we develop can be used to explain how variables such as growth rate, nutrition, and temperature affect body size.ConclusionOur analysis shows that there is no single locus of control of body size, but that body size is a system property that depends on interactions among the underlying determinants of the three fundamental parameters. A deeper mechanistic understanding of body size will be obtained by research aimed at uncovering the molecular mechanisms that give these three parameters their particular quantitative values.

A socially enforced signal of quality in a paper wasp

Organisms use signals of quality to communicate information about aspects of their relative phenotypic and genetic constitution. Badges of status are a subset of signals of quality that reveal information about an individual's size and dominance. In general, signals of quality require high and differential costs to remain honest (that is, prevent low-quality cheaters from exploiting any fitness benefits associated with communicating high quality). The theoretically required costs for badges of status remain controversial because the development (or 'production') of such signals often seems to be relatively cost-free. One important hypothesis is that such signals impose social (or 'maintenance') costs incurred through repeated agonistic interactions with other individuals. However, convincing empirical evidence for social costs remains elusive. Here we report social costs in a previously undescribed badge of status: the highly variable black facial patterns of female paper wasps, Polistes dominulus. Facial patterns strongly predict body size and social dominance. Moreover, in staged contests between pairs of unfamiliar wasps, subordinate wasps with experimentally altered facial features ('cheaters') received considerably more aggression from the dominant than did sham controls, indicating that facial patterns are signals and that dishonest signalling imposes social costs.

Multiple Ornaments in Male Northern Cardinals,Cardinalis cardinalis, as Indicators of Condition

AbstractInvestigations of male ornaments in the context of sexual selection have tended to focus on single ornaments, although many species of birds possess multiple ornaments. Understanding the evolution of multiple ornaments requires knowledge of correlations among ornaments in the same individual and the extent to which ornament expression reflects individual condition and behavior. Variation in four male ornaments in socially monogamous, biparental northern cardinals (Cardinalis cardinalis) was related to body size, indices of condition, level of paternal care, and reproductive success. Redness of breast plumage positively predicted body size and negatively predicted nestling feeding rate. Bill color predicted current body condition, with birds with redder bills in better condition. Birds with smaller black face masks had greater reproductive success. These results are consistent with the hypothesis that different ornaments in male cardinals provide information on different aspects of condition and behavior.

Prenatal factors, childhood growth trajectories and age at menarche

In recent studies a larger birth size has been shown to delay the timing of menarche. The mechanisms underlying this association are not clear, however, as birthweight is a predictor of body size in childhood, and a large body size is known to be associated with an early onset of menarche. Data from a representative British cohort of 2547 girls born in 1946 who were followed prospectively throughout childhood were used. Information was available on prenatal characteristics, birthweight, height, weight and social circumstances during childhood, and on age at menarche. Random coefficients models were used to estimate the individual trajectories in height and body mass index (BMI) up to age 7 years. The parameters identified by these models were then included in Weibull survival models for the timing of menarche together with birthweight. Birthweight was found to positively influence height and BMI values at age 2 years, but not to affect their rates of change from age 2 to 7 years. Initial analyses showed low birthweight to be associated with an early onset of menarche, but after controlling for growth in infancy this effect was reversed, with girls who were heavy at birth reaching menarche earlier than others with similar infant growth. Rapid growth in infancy was also related to early pubertal maturation. The effects of birthweight and infant growth disappeared, however, when further controlled for growth from age 2 to 7 years. The effects of birthweight and growth in infancy on the timing of menarche seem to be mediated through growth in early childhood. These findings are consistent with the possibility that timing of menarche may be set in utero or early in life, although it may be modified by changes in body size and composition in childhood.

Prenatal factors, childhood growth trajectories and age at menarche

Background In recent studies a larger birth size has been shown to delay the timing of menarche. The mechanisms underlying this association are not clear, however, as birthweight is a predictor of body size in childhood, and a large body size is known to be associated with an early onset of menarche. Methods Data from a representative British cohort of 2547 girls born in 1946 who were followed prospectively throughout childhood were used. Information was available on prenatal characteristics, birthweight, height, weight and social circumstances during childhood, and on age at menarche. Random coefficients models were used to estimate the individual trajectories in height and body mass index (BMI) up to age 7 years. The parameters identified by these models were then included in Weibull survival models for the timing of menarche together with birthweight. Results Birthweight was found to positively influence height and BMI values at age 2 years, but not to affect their rates of change from age 2 to 7 years. Initial analyses showed low birthweight to be associated with an early onset of menarche, but after controlling for growth in infancy this effect was reversed, with girls who were heavy at birth reaching menarche earlier than others with similar infant growth. Rapid growth in infancy was also related to early pubertal maturation. The effects of birthweight and infant growth disappeared, however, when further controlled for growth from age 2 to 7 years. Conclusions The effects of birthweight and growth in infancy on the timing of menarche seem to be mediated through growth in early childhood. These findings are consistent with the possibility that timing of menarche may be set in utero or early in life, although it may be modified by changes in body size and composition in childhood.

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Similarities in Body Image in Sisters: The Role of Sociocultural Internalization and Social Comparison

The sociocultural theory of body image disturbance states that Western women experience pressure from sources such as parents, peers, and the media to maintain thinness. Social comparison theory emphasises the role of comparing one's appearance to others. Body image disturbance; awareness and Internalization of sociocultural messages regarding thinness; and sibling social comparisons were examined in 41 closest-in-age sisters through self-report questionnaires. Sisters showed similar levels of body image disturbance and sociocultural awareness and internalization. Sibling comparisons were negative for younger sisters but neutral or positive for older sisters. Sociocultural internalization predicted body dissatisfaction in both sisters, and body size distortion in younger sisters. Negative sibling comparisons during teenage years predicted body size distortion and body dissatisfaction in younger sisters, and preference for thinness in older sisters.

THE RELIABILITY OF SKINFOLD-CALIPERS FOR MEASURING BLUBBER THICKNESS OF STELLER SEA LION PUPS (EUMETOPIAS JUBATUS)

Twelve dead Steller sea lion pups (Eumetopias jubatus) aged 3-14 d were recovered from rookeries in Southeast Alaska. They had a wide range of body sizes and conditions (small to large and fat to no fat). The ability of calipers to estimate the thickness of their blubber layer was assessed with a set of skinfold calipers. Average error of measurement for skin and blubber thickness was an acceptable 5.4%, but the skin and blubber of the pups were highly compressible. Skinfold thickness increased with body mass but did not necessarily reflect the development of blubber, given that pups with no blubber also showed an increase in skinfold thickness with increases in body mass. Skinfold thickness of sea lion pups appears to predict body size better than it predicts blubber thickness, making it difficult if not impossible to develop a simple index of body condition or a calculation of percent body fat for Steller sea lion pups from skinfold caliper measurements.

Natural history of the growth of the hand: part II--hand length as a treatment guide in the pediatric trauma patient.

In a previous study, we defined the natural history of the growth of the hand. In particular, we demonstrated that the palmar aspect of the hand is approximately 0.78% of body surface area (BSA). We also demonstrated a relationship between the area of the palmar surface of the hand and the total BSA as growth proceeds. Seeking to improve the usefulness of hand size as a guide to predicting body size, we examined the length of the hand as a predictor of body mass and BSA. Bilateral hand tracings were obtained from 800 volunteers ranging in age from 2 to 89 years. The hand tracings were measured, and the length and width of the hands were determined. The height and weight of each individual were measured, and his or her BSA was calculated. The data was subjected to statistical and graphical analyses. Hand length is an excellent predictor of BSA and body mass. Hand length as a predictor of body size is independent of the gender of the subject and most accurate for ages 2 to 17 years. The correlation is so highly predictive that it is possible to derive a treatment guide based on hand length. The length of the hand predicts body weight and BSA and can be used to predict baseline intravenous fluid requirements and the volume of packed red blood cells to be transfused to raise the hematocrit 3%. Hand length is a simple measurement that may be used as a treatment guide. Hand length will predict body weight and body surface area independently of the gender of the subject.

Bergmann's rule in the ant lion Myrmeleon immaculatus DeGeer (Neuroptera: Myrmeleontidae): geographic variation in body size and heterozygosity

Summary Aim Geographic variation in body size and heterozygosity were surveyed for discrete populations of the ant lion, Myrmeleon immaculatus DeGeer, collected from the central and northeastern United States. LocationCollection sites were located in the central and eastern United States ranging from western Oklahoma to northern New York. Methods We collected 872 M. immaculatus larvae from thirty‐four collecting sites. At each site, we randomly sampled ant lion pits and collected between fifteen and fifty‐two larvae in total. Larvae were preserved in 95% ETOH for morphological analysis and frozen in a −80°C freezer for protein electrophoresis. We measured the body size of eighty‐five preserved adult M. immaculatus obtained from museum collections using head width as an indicator of body size. Five enzymes [GPI (glucose phosphate isomerase), MDH (malate dehydrogenase), PEP (peptidase), DIA (diaphorase) and SOD (superoxide dismutase)] were used in the heterozygosity analyses. Results Larval and adult body size increased with latitude, but decreased with elevation. Average heterozygosity, measured at five polymorphic loci, also increased significantly with latitude. Minimum temperature variance was the best predictor of body size, whereas precipitation and maximum temperature were the best predictors of heterozygosity. Populations were genetically differentiated from one another and showed a pattern of isolation by distance, as measured by Wright's Fst values and Nei's genetic distances. Main conclusions Sampling artifacts, heat conservation, character displacement, cell‐size variation, density‐dependent mortality, and differential dispersal probably cannot account for latitudinal variation in ant lion body size. Our results implicate the importance of diurnal photoperiod, which varies with latitude, but not with elevation. Because photoperiod often controls growth, diapause, and metamorphosis, it may be an important determinant of latitudinal clines in body size and life history of insects.

Visual cues to female physical attractiveness.

Evolutionary psychology suggests that a woman's sexual attractiveness is based on cues of health and reproductive potential. In recent years, research has focused on the ratio of the width of the waist to the width of the hips (the waist-to-hip ratio (WHR). A low WHR (i.e. a curvaceous body) is believed to correspond to the optimal fat distribution for high fertility, and so this shape should be highly attractive. In this paper we present evidence that weight scaled for height (the body mass index (BMI)) is the primary determinant of sexual attractiveness rather than WHR. BMI is also strongly linked to health and reproductive potential. Furthermore, we show how covariation of apparent BMI and WHR in previous studies led to the overestimation of the importance of WHR in the perception of female attractiveness. Finally, we show how visual cues, such as the perimeter-area ratio (PAR), can provide an accurate and reliable index of an individual's BMI and could be used by an observer to differentiate between potential partners.

Self-concept and body-image disturbance: Which self-beliefs predict body size overestimation?

Two studies investigated the relation between self-concept and body-image disturbance in selected female undergraduates. In each study, high- and low-body-shape-concerned women completed a set of self-concept assessments, including both appearance-specific questions and a measure of general self-discrepancies. One month later, they participated in an experiment in which they made judgments comparing the sizes of body silhouettes to their own bodies. Signal detection analysis indicated that the groups differed significantly on the criterion for deciding that a silhouette was larger than their own bodies (bias) but not on the ability to accurately discriminate among silhouettes (sensitivity). Among self-concept measures, overall actual:ideal self-discrepancy was the best predictor of subjects' biases in estimating their own body sizes.

The sounds of bicolor damselfish (Pomacentrus partitus): Predictors of body size and a spectral basis for individual recognition and assessment

Evidence is provided that the ‘‘chirp,’’ a sound commonly produced by males of the bicolor damselfish (family: Pomacentridae) possesses an anatomical constraint: The peak frequency within its power spectrum reflects a clear inverse relationship to body size. For every 1-mm change in the standard length of a male (range: 50–69 mm), the peak frequency of its sounds shifts by approximately 20 Hz. The ultimate constraint appears to be the volume of an individual’s gas bladder. This provides an individualistic feature to the sounds of different sized colony members, all of whose sounds possess an otherwise extremely stereotyped temporal pattern of their included pulses. This finding may aid in clarifying the mechanism that provides the clue for the already established acoustical recognition of individuals within colonies of the species.

Self-Discrepancy Theory as a Framework for Understanding Bulimic Symptomatology and Associated Distress

Self-Discrepancy Theory as a Framework for Understanding Bulimic Symptomatology and Associated DistressMaureen T. Forston and Annette L. StantonMaureen T. ForstonSearch for more papers by this author and Annette L. Stanton1 Auburn University2 University of KansasSearch for more papers by this authorPublished Online:January 2011PDFPDF PLUS ShareShare onFacebookTwitterLinkedInRedditEmail ToolsAdd to favoritesDownload CitationsTrack Citations About Next article FiguresReferencesRelatedDetails Cited byCited by1. Images of bodies in mass and social media and body dissatisfaction: The role of internalization and self-discrepancyOnline publication date: 20 December 2022. Go to citation Crossref Google Scholar2. Who we are and how we feel: Self-discrepancy theory and specific affective statesOnline publication date: Go to citation Crossref Google Scholar3. Online publication date: Go to citation Crossref Google Scholar4. The Relationship Between Body Image Concerns, Eating Disorders and Internet Use, Part II: An Integrated Theoretical ModelOnline publication date: 7 October 2015. Go to citation Crossref Google Scholar5. Relationship between self-discrepancy and worries about penis size in men with body dysmorphic disorderOnline publication date: Go to citation Crossref Google Scholar6. Inspired by Hope, Motivated by Envy: Comparing the Effects of Discrete Emotions in the Process of Social Comparison to Media FiguresOnline publication date: 1 April 2014. Go to citation Crossref Google ScholarKristin E. Heron and Joshua M. Smyth7. Body Image Discrepancy and Negative Affect in Women's Everyday Lives: An Ecological Momentary Assessment Evaluation of Self-Discrepancy TheoryOnline publication date: 27 February 2013. Go to citation Crossref Google Scholar8. Body self-discrepancies and women's social physique anxiety: The moderating role of the feared bodyOnline publication date: 8 March 2011. Go to citation Crossref Google Scholar9. Bulimic and Depressive Symptoms: Self-Discrepancies and AcceptanceOnline publication date: 3 September 2010. Go to citation Crossref Google Scholar10. Subclinical bulimia vs. depression in an interpersonal contextOnline publication date: Go to citation Crossref Google Scholar11. Women’s and Men’s Eating Behavior Following Exposure to Ideal-Body Images and TextOnline publication date: 29 June 2016. Go to citation Crossref Google Scholar12. Associations Between Appearance-Related Self-Discrepancies and Young Women's and Men's Affect, Body Satisfaction, and Emotional Eating: A Comparison of Fixed-Item and Participant-Generated Self-DiscrepanciesOnline publication date: 2 July 2016. Go to citation Crossref Google Scholar13. Television and Perceived Peer Expectations of Body Size Among African American Adolescent GirlsOnline publication date: Go to citation Crossref Google Scholar14. Indoor lighting preferences and bulimic behaviorOnline publication date: Go to citation Crossref Google ScholarKristen Harrison15. Ourselves, Our Bodies: Thin-Ideal Media, Self-Discrepancies, and Eating Disorder Symptomatology in AdolescentsOnline publication date: 1 June 2005. Go to citation Crossref Google Scholar16. Own versus Other Standpoints in Self-Regulation: Developmental Antecedents and Functional ConsequencesOnline publication date: 1 September 1999. Go to citation Crossref Google Scholar17. Self-Discrepancy Theory, Standards for Body Evaluation, and Eating Disorder Symptomatology Among College WomenOnline publication date: Go to citation Crossref Google Scholar18. Cultural Differences in the Relation between Self-discrepancy and Life SatisfactionOnline publication date: Go to citation Crossref Google Scholar19. Body image: A cognitive self-schema construct?Online publication date: Go to citation Crossref Google ScholarMarcela L. Szymanski and Thomas F. Cash20. Body-Image Disturbances and Self-Discrepancy Theory: Expansion of the Body-Image Ideals QuestionnaireOnline publication date: 21 January 2011. Go to citation Crossref Google Scholar21. The Development and Validation of the Body-Image Ideals QuestionnaireOnline publication date: Go to citation Crossref Google Scholar22. Self-concept and body-image disturbance: Which self-beliefs predict body size overestimation?Online publication date: Go to citation Crossref Google Scholar23. In Pursuit of the Perfect Appearance: Discrepancies Among Self-Ideal Percepts of Multiple Physical Attributes 1Online publication date: Go to citation Crossref Google Scholar Volume 11Issue 2Jun 1992 Information© 1992 Guilford Publications Inc.PDF download

Obesity in offspring of diabetic Pima Indian women despite normal birth weight.

The relationships of birth weight and maternal diabetes to the development of obesity were examined at 5-19 yr of age in the offspring of Pima Indian women. At each age, offspring of diabetic women, even those who were of normal birth weight, had a higher mean weight relative to height than offspring of nondiabetic and prediabetic women. Birth weight was predictive of relative weight in 5- to 9- and 10- to 14-yr-old offspring of nondiabetic women but not in the oldest group. In contrast, for offspring of prediabetic and diabetic women, birth weight was not predictive of subsequent obesity at any age studied. Offspring of diabetic women were heavier than offspring of nondiabetic and prediabetic women regardless of birth weight. Thus, maternal diabetes was important in predicting body size in the offspring even after accounting for the effects of the birth weight and maternal body size.