Determinants of variation in adult body height

Final body height is achieved as the result of a combination of genetic and environmental factors. The aim of this article is to review past studies on body height that have followed different scientific traditions. In modern Western societies, about 20% of variation in body height is due to environmental variation. In poorer environments, this proportion is probably larger, with lower heritability of body height as well as larger socioeconomic body height differences. The role of childhood environment is seen in the increase in body height during the 20th century simultaneously with the increase in the standard of living. The most important non-genetic factors affecting growth and adult body height are nutrition and diseases. Short stature is associated with poorer education and lower social position in adulthood. This is mainly due to family background, but other environmental factors in childhood also contribute to this association. Body height is a good indicator of childhood living conditions, not only in developing countries but also in modern Western societies. Future studies combining different scientific traditions in auxology are needed to create a more holistic view of body height.     

How Humans Differ from Other Animals in Their Levels of Morphological Variation

Animal species come in many shapes and sizes, as do the individuals and populations that make up each species. To us, humans might seem to show particularly high levels of morphological variation, but perhaps this perception is simply based on enhanced recognition of individual conspecifics relative to individual heterospecifics. We here more objectively ask how humans compare to other animals in terms of body size variation. We quantitatively compare levels of variation in body length (height) and mass within and among 99 human populations and 848 animal populations (210 species). We find that humans show low levels of within-population body height variation in comparison to body length variation in other animals. Humans do not, however, show distinctive levels of within-population body mass variation, nor of among-population body height or mass variation. These results are consistent with the idea that natural and sexual selection have reduced human height variation within populations, while maintaining it among populations. We therefore hypothesize that humans have evolved on a rugged adaptive landscape with strong selection for body height optima that differ among locations.     

Relationship of body composition to somatotype.

The purpose of this study is to determine the relationship in college-aged women between somatotype using both Sheldon's ('69) and Heath and Carter's ('67) procedures, and body composition, as measured by whole-body 40K counting and body density. Sheldon's endomorphy is closely associated with height and weight; Heath and Carter's first component is significantly related to weight and body fatness. Lean body mass (LBM) as a weight or as a percent is not closely related to Sheldon's mesomorphy or Heath and Carter's second component. However, when LBM and height are used as independent variables to estimate somatotype, both variables are significantly related to Heath and Carter's second component, accounting for 61% of the variance. Thus Heath and Carter's second component is significantly associated with LBM for a given body height. Most of the variation in Sheldon's ectomorphy and Heath and Carter's third component can be accounted for by weight and height. Sheldon's somatotype for all three components is not as closely related to body composition as Heath-Carter's. Body composition, as measured by either 40K counting or body density, is found to be important in accounting for variation in Heath and Carter's first and second components.     

哈萨克族中小学生体质发育资料及身体发育指数分析

本文报告了新疆阿勒泰地区7—18岁哈萨克族中小学生体质发育的调查结果。重点分析3456名城镇哈萨克族学生的体质发育资料。体质发育调查指标包括身高、体重、胸围、坐高、肩宽、骨盆宽六项,其增长幅度及变异度皆以体重为大。哈萨克族学生的身高不论男女,在多数年龄组小于国内同龄汉族学生,而体重则多数年龄组大于国内同龄汉族。本文还分析了哈萨克族学生的六项身体发育指数。     

Reduced insulin/IGF-1 signalling and human longevity

Evidence is accumulating that aging is hormonally regulated by an evolutionarily conserved insulin/IGF-1 signalling (IIS) pathway. Mutations in IIS components affect lifespan in Caenorhabditis elegans, Drosophila melanogaster and mice. Most long-lived IIS mutants also show increased resistance to oxidative stress. In D. melanogaster and mice, the long-lived phenotype of several IIS mutants is restricted to females. Here, we analysed the relationship between IIS signalling, body height and longevity in humans in a prospective follow-up study. Based on the expected effects (increased or decreased signalling) of the selected variants in IIS pathway components (GHRHR, GH1, IGF1, INS, IRS1), we calculated composite IIS scores to estimate IIS pathway activity. In addition, we analysed the relative impact on lifespan and body size of the separate variants in multivariate models. In women, lower IIS scores are significantly associated with lower body height and improved old age survival. Multivariate analyses showed that these results were most pronounced for the GH1 SNP, IGF1 CA repeat and IRS1 SNP. In females, for variant allele carriers of the GH1 SNP, body height was 2 cm lower (P = 0.007) and mortality 0.80-fold reduced (P = 0.019) when compared with wild-type allele carriers. Thus, in females, genetic variation causing reduced IIS activation is beneficial for old age survival. This effect was stronger for the GH1 SNP than for variation in the conserved IIS genes that were found to affect longevity in model organisms.     

Heritability of adult body height: a comparative study of twin cohorts in eight countries.

A major component of variation in body height is due to genetic differences, but environmental factors have a substantial contributory effect. In this study we aimed to analyse whether the genetic architecture of body height varies between affluent western societies. We analysed twin data from eight countries comprising 30,111 complete twin pairs by using the univariate genetic model of the Mx statistical package. Body height and zygosity were self-reported in seven populations and measured directly in one population. We found that there was substantial variation in mean body height between countries; body height was least in Italy (177 cm in men and 163 cm in women) and greatest in the Netherlands (184 cm and 171 cm, respectively). In men there was no corresponding variation in heritability of body height, heritability estimates ranging from 0.87 to 0.93 in populations under an additive genes/unique environment (AE) model. Among women the heritability estimates were generally lower than among men with greater variation between countries, ranging from 0.68 to 0.84 when an additive genes/shared environment/unique environment (ACE) model was used. In four populations where an AE model fit equally well or better, heritability ranged from 0.89 to 0.93. This difference between the sexes was mainly due to the effect of the shared environmental component of variance, which appears to be more important among women than among men in our study populations. Our results indicate that, in general, there are only minor differences in the genetic architecture of height between affluent Caucasian populations, especially among men.     

Diurnal variation in stature - Is it more in children or adults?

Stature is the most often used anthropometric measure in the nutritional, growth and development, anthropological and forensic oriented studies. Its estimate is considered to be an important assessment in the identification of unknown human remains and its medico-legal significance is obvious in forensic examinations. Diurnal variation in stature is a biological norm in the human body and its effects can be reflected in the reliability of height data in these studies. We hypothesize that the extent of diurnal variation is more in children as compared to adults in a population.     

Body height of mummified pharaohs supports historical suggestions of sibling marriages

Body height is an important factor in reconstructing health conditions and it serves as an indicator of socio‐economic status. Researchers rely on ancient data to analyze evolutionary aspects of human health and its interrelation with environmental influences. This study presents body height estimates from all periods of ancient Egyptian history and compares the general population with the existing mummies of the members of royal families. A sample of 259 adult Egyptian mummies originating from various collections and published sources with body lengths (long bone measures or/and overall measurements, CT data) were analyzed, and royal mummies were scored with respect to the level of consanguinity. Male royals were taller than males in the general ancient Egyptian population, while female royals were shorter than females in the general population. The body height variation of the royals is significantly reduced when compared with a pool of non‐royal mummies. This provides evidence for inbreeding resulting from consanguineous marriages. However, there appears to be no correlation between the level of inbreeding and individual body height. The random sample of general population does not show signs of inbreeding. Due to the present lack of larger, technically and ethically challenging genetic studies, the selected non‐invasive approach of body height is the most reliable indicator of sibling marriages of pharaohs based on direct physical evidence. Am J Phys Anthropol 157:519–525, 2015. © 2015 Wiley Periodicals, Inc.     

Ontogenetic changes in genetic variances of age-dependent plasticity along a latitudinal gradient

The expression of phenotypic plasticity may differ among life stages of the same organism. Age-dependent plasticity can be important for adaptation to heterogeneous environments, but this has only recently been recognized. Whether age-dependent plasticity is a common outcome of local adaptation and whether populations harbor genetic variation in this respect remains largely unknown. To answer these questions, we estimated levels of additive genetic variation in age-dependent plasticity in six species of damselflies sampled from 18 populations along a latitudinal gradient spanning 3600 km. We reared full sib larvae at three temperatures and estimated genetic variances in the height and slope of thermal reaction norms of body size at three points in time during ontogeny using random regression. Our data show that most populations harbor genetic variation in growth rate (reaction norm height) in all ontogenetic stages, but only some populations and ontogenetic stages were found to harbor genetic variation in thermal plasticity (reaction norm slope). Genetic variances in reaction norm height differed among species, while genetic variances in reaction norm slope differed among populations. The slope of the ontogenetic trend in genetic variances of both reaction norm height and slope increased with latitude. We propose that differences in genetic variances reflect temporal and spatial variation in the strength and direction of natural selection on growth trajectories and age-dependent plasticity. Selection on age-dependent plasticity may depend on the interaction between temperature seasonality and time constraints associated with variation in life history traits such as generation length.     

The relationship between nephron number,kidney size and body weight in two inbred mouse strains

While some reports in humans have shown that nephron number is positively correlated with height, body weight or kidney weight, other studies have not reproduced these findings. To understand the impact of genetic and environmental variation on these relationships, we examined whether nephron number correlates with body weight, kidney planar surface area, or kidney weight in two inbred mouse strains with contrasting kidney sizes but no overt renal pathology: C3H/HeJ and C57BL/6J. C3H/HeJ mice had smaller kidneys at birth and larger kidneys by adulthood, however there was no significant difference in nephron number between the two strains. We did observe a correlation between kidney size and body weight at birth and at adulthood for both strains. However, there was no relationship between nephron number and body weight or between nephron number and kidney size. From other studies, it appears that a greater than 2-fold variation is required in each of these parameters in order to demonstrate these relationships, suggesting they are highly dependent on scale. Our results are therefore not surprising since there was a less than 2-fold variation in each of the parameters examined. In summary, the relationship between nephron number and body or kidney size is most likely to be demonstrated when there is greater phenotypic variation either from genetic and/or environmental factors.     

The relationship between nephron number, kidney size and body weight in two inbred mouse strains

While some reports in humans have shown that nephron number is positively correlated with height, body weight or kidney weight, other studies have not reproduced these findings. To understand the impact of genetic and environmental variation on these relationships, we examined whether nephron number correlates with body weight, kidney planar surface area, or kidney weight in two inbred mouse strains with contrasting kidney sizes but no overt renal pathology: C3H/HeJ and C57BL/6J. C3H/HeJ mice had smaller kidneys at birth and larger kidneys by adulthood, however there was no significant difference in nephron number between the two strains. We did observe a correlation between kidney size and body weight at birth and at adulthood for both strains. However, there was no relationship between nephron number and body weight or between nephron number and kidney size. From other studies, it appears that a greater than two-fold variation is required in each of these parameters in order to demonstrate these relationships, suggesting they are highly dependent on scale. Our results are therefore not surprising since there was a less than two-fold variation in each of the parameters examined. In summary, the relationship between nephron number and body or kidney size is most likely to be demonstrated when there is greater phenotypic variation either from genetic and/or environmental factors.     

Sports-anthropological analysis of Tunisian elite karateka

This study is based on a careful sport anthropological investigation (ca. 15 min) of 25 Tunisian athletes of the Karate team (aged 18 - 31 years) with special permission of the Tunisian Ministry of Youth and Sports. Considering the height of the Tunisian elite athletes (175.6 +/- 4.9 cm), heavier kareteka are bigger (178.9 +/- 2.2 cm vs. 171.4 +/- 3.9 cm). The mean weight was 73.1 +/- 8.2 kg (heavier athletes 78.7 +/- 5.9 kg vs. lighter athletes 66.0 +/- 4.1 kg). On Conrad's chessboard diagram all the Tunisian karateka were placed in the leptomorph half, only two in the metromorph corridor, but most of them in the middle between hypoplastic and hyperplastic poles. The AKS index diagram demonstrates a faint diagonal positioning of the single weight categories, with progression of body mass from the lower to the upper right area. None of the athletes surpasses a body height of 184 cm. The variation of the AKS index is higher than the variation of body height. The constitutional analysis according to Knussmann (1961) reveals an orientation of heavier weight classes towards macrosomia and pyknomorphism. The proportional figures of the athletes show a small variation of joint heights in lower extremities. In Parnell's somatochart (1954, 1958) the concentration of Tunisian karateka is found in the mesoectomorph third as well as in the somatochart of Heath & Carter (1967). Further sport anthropological karate studies should focus on adolescents and females as well as on physiological and biomechanic parameters.     

Foraging ecology and niche partitioning in orb-weaving spiders

Summary Foraging patterns were determined for three orbweaving spiders in several geographical locations varying in percent cover by herbaceous vegetation. Argiope trifasciata was the most common species in early successional habitats, while both Argiope aurantia and Araneus trifolium were more common in wetter, more herbaceous sites. Discriminant analysis revealed that web height selected for webs and body size were the variables that explained most of the variation among populations in foraging patterns. Argiope aurantia forages lowest in vegetation, A. trifasciata at intermediate heights, and A. trifolium near the top of the vegetation. The body size sequence is reversed.Web radius, spider size, and web height appear to explain much of the variation in abundance and size of prey in webs. Species foraging higher in the vegetation take more winged prey, while larger species foraging lower in the vegetation tend to take larger, jumping prey like acridids. Comparison of prey in webs with field estimates of potential prey suggests that orbweavers select large insect prey. Inferential evidence indicates that interspecific competition may be responsible for the divergence in foraging patterns among species reported here. However, field manipulative experiments have not yet indicated that competition among orb-weavers is severe.     

Simple anthropometric and physical performance tests to predict maximal box-lifting ability

Box-lifting ability is an important characteristic of military personnel. The purpose of this paper was to determine the usefulness of the upright row free weight exercise and simple anthropometric tests to predict maximal box-lifting performance that simulates the loading of military supply vehicles. Two groups of adults performed maximal box lifts to 1.4 m (study 1) and 1.7 m (study 2), respectively. All subjects were also tested for upright row 1 repetition maximum (1RM) strength, body mass, height, and body composition. In study 1, a remarkably good prediction of maximal box-lift performance to 1.4 m (42 +/- 12 kg) was obtained from a regression equation including the variables body mass, body composition, and upright row 1RM. Approximately 95% of the variation in 1.4-m box-lifting performance could be accounted for. In contrast, in study 2, only 80% of the variation in 1.7-m box-lifting performance (51 +/- 15 kg) could be accounted for by the best predictor equation. Upright row 1RM strength appears to be a useful tool in the prediction of box-lifting ability to approximately chest height for most adults, probably due to a close match between the muscle groups and contraction modes required during both tasks. Military or other organizations could use the data reported here to substitute simple anthropometry and a 1RM test of strength and for the direct assessment of 1.4-m box-lifting performance.     

Population-demographic structure of the population of Kursk region: anthropometric profile of newborn children

Based on the characteristics of body height and weight in 4905 newborns, the population-genetic structure of the rural raions (districts) of Kursk oblast (region) and in the city of Kursk was determined. An "adaptive norm area" with respect to body weight and height was distinguished for newborns in Kursk oblast. On the average, the anthropometric parameters of 20% of infants from the studied populations fell within this area. The height and growth of newborns exhibited a pronounced geographic variation and depended on the level of urbanization, as well as the sex and the health status of the newborns. In district populations, the body height and the variances of the body height and weight increased with an increase in endogamy. Therefore, the relative numbers of newborns with large values of both weight and height, as well as those with a medium body height and a small body weight, were increased. Conversely, the relative numbers of newborns with a low weight and height and with a disturbed weight-height correlation were decreased.     

The use of biocultural data in interpreting sex differences in body proportions among rural Amazonians

Variation in height and body proportions is relatively well-understood at the inter-population level, but less is known about intra-population variation. This study explores intra-population variation in body proportions among 172 (88 female; 84 male) adult rural Amazonians. We test the hypotheses that: (1) stunting is associated with changes in proportions and fatness; (2) the sexes express different proportions in response to similar environmental stress; and (3) female growth is negatively affected by the costs of reproduction. We examined height, sitting height, and total leg length in subsamples based on sex and nutritional status (stunted/nonstunted) in relation to biocultural factors including access to food and healthcare and female reproductive history parameters. Differences in proportions were examined using the Quick-Test (Tsutakawa and Hewett: Biometrics 33 (1977) 215-219); correlation analyses were used to detect associations between anthropometric data and body fatness, and female reproductive history parameters. We found significantly higher rates of stunting among females (X(2) = 5.31; P = 0.02; RR = 1.4). Stunted individuals exhibited relatively shorter legs than nonstunted individuals (P = 0.02), although this was not found in within-sex analyses. A significant negative correlation was found between leg length index and fatness (P < 0.01). Lastly, females exhibited relatively shorter legs than males (P = 0.0003) and, among females, height and leg length were significantly positively correlated with age-at-first-birth (P < 0.02) suggesting that adolescent pregnancy may negatively affect growth in this population. Our findings provide insights for the study of intra-population variation in body proportions and highlight the importance of biocultural data in interpreting the pattern of variation observed in living and past populations.     

Using photogrammetry and color scoring to assess sexual dimorphism in wild western gorillas (Gorilla gorilla)

Investigating sexual dimorphism is important for our understanding of its influence on reproductive strategies including male-male competition, mate choice, and sexual conflict. Measuring physical traits in wild animals can be logistically challenging and disruptive for the animals. Therefore body size and ornament variation in wild primates have rarely been quantified. Gorillas are amongst the most sexually dimorphic and dichromatic primates. Adult males (silverbacks) possess a prominent sagittal crest, a pad of fibrous and fatty tissue on top of the head, have red crest coloration, their saddle appears silver, and they possess a silverline along their stomach. Here we measure levels of sexual dimorphism and within-male variation of body length, head size, and sexual dichromatism in a population of wild western gorillas using photogrammetry. Digital photogrammetry is a useful and precise method to measure sexual dimorphism in physical traits yielding sexual dimorphism indices (ISD), similar to those derived from traditional measurements of skeletal remains. Silverbacks were on an average 1.23 times longer in body length than adult females. Sexual dimorphism of head size was highest in measures of crest size (max ISD: 60.4) compared with measures of facial height (max ISD: 24.7). The most sexually dimorphic head size measures also showed the highest within-sex variation. We found no clear sex differences in crest coloration but there was large sexual dichromatism with high within-male variation in saddle coloration and silverline size. Further studies should examine if these sexually dimorphic traits are honest signals of competitive ability and confer an advantage in reproductive success.     

Normalization of joint moments during gait: a comparison of two techniques

Joint moments are commonly used to characterize gait. Factors like height and weight influence these moments. This study determined which of two commonly used normalization methods, body mass or body weight times height, most reduced the effects of height and weight on peak hip, knee, and ankle external moments during walking. The effectiveness of each normalization method in reducing gender differences was then tested. Gait data from 158 normal subjects were analyzed using unnormalized values, body mass normalized values, and body weight times height normalized values. Without normalization, height or weight accounted for 7-82% of the variance in all 10 peak components of the moments. With normalization, height and weight accounted for at most 6% of the variance with the exception of the hip adduction moment normalized by body weight times height and the ankle dorsiflexion moment normalized by body mass. For the hip adduction moment normalized by body weight times height, height still accounted for 13% of the variance (p<0.001) and for the ankle dorsiflexion moment normalized by body mass, 22% of the variance (p<0.001). After normalization, significant differences between males and females remained for only two out of 10 moments with the body weight times height method compared to six out of 10 moments with the body mass method. When compared to the unnormalized data, both normalization methods were highly effective in reducing height and weight differences. Even for the two cases where one normalization method was less effective than the other (hip adduction-body weight times height; ankle dorsiflexion-body mass) the normalization process reduced the variance ascribed to height or weight by 48% and 63%, respectively, as compared to the unnormalized data.     

Dosing of growth hormone in growth hormone deficiency

Growth hormone (GH) treatment of GH-deficient (GHD) children is to a certain extent standardized worldwide. Recombinant 22 kDa GH is injected once daily by the subcutaneous route, mostly in the evening. The amount of GH injected (calculated per kg body weight or body surface area, expressed in terms of IU or mg) in prepubertal children mimics the known production rate (approximately 0.02 mg [0. 06 IU]/kg body weight per day). However, there is a wide variation in dosage, the reasons for which are partly unknown and partly due to national traditions and regimes imposed by authorities regulating reimbursement. The situation during puberty is less standardized, with most clinicians still not increasing the dosage according to known production rates. The results of these approaches in terms of adult height outcome are not always satisfactory. In order to achieve optimal height development during childhood, puberty and adulthood, strategies must be developed to individualize GH dosing according to set therapeutical goals taking into account efficacy, safety and cost. The implementation of prediction algorithms will help us to reach these goals. In addition, other response variables will have to be monitored during treatment in order to correct for deficits resulting from GHD.     

Birth month associations with height,head circumference,and limb lengths among peruvian children

Associations between season of birth and body size, morbidity, and mortality have been widely documented, but it is unclear whether different parts of the body are differentially sensitive, and if such effects persist through childhood. This may be relevant to understanding the relationship between early life environment and body size and proportions. We investigated associations between birth month and anthropometry among rural highland (n = 162) and urban lowland (n = 184) Peruvian children aged 6 months to 8 years. Stature; head‐trunk height; total limb, ulna, tibia, hand, and foot lengths; head circumference; and limb measurements relative to head‐trunk height were converted to internal age‐sex‐specific z scores. Lowland and highland datasets were then analyzed separately for birth month trends using cosinor analysis, as urban conditions likely provide a more consistent environment compared with anticipated seasonal variation in the rural highlands. Among highland children birth month associations were significant most strongly for tibia length, followed by total lower limb length and stature, with a peak among November births. Results were not significant for other measurements or among lowland children. The results suggest a prenatal or early postnatal environmental effect on growth that is more marked in limb lengths than trunk length or head size, and persists across the age range studied. We suggest that the results may reflect seasonal variation in maternal nutrition in the rural highlands, but other hypotheses such as variation in maternal vitamin D levels cannot be excluded. Am J Phys Anthropol 154:115–124, 2014. © 2014 The Authors. American Journal of Physical Anthropology Published by Wiley Periodicals, Inc.