Anthropometric fluctuating asymmetries in living humans through the eyes of an anthropologist.

There are many environmental and genetic factors that disrupt the stable structure of development in organisms. Although the strength of these vary, they leave certain signs in the body structure. Fluctuating asymmetry is a widely used population-level index of developmental instability, developmental noise, and robustness. Many bilateral traits are used in fluctuating asymmetry studies in humans. These traits include dermatoglyphics, limb lengths and widths, bilateral facial characters, and teeth. In this review, I evaluate the measurement methods of many bilateral anthropometric characters, taken from the bodies of living individuals with classical digital calipers.

Factors Associated With Highest Symptoms of Anxiety During COVID-19: Cross-Cultural Study of 23 Countries.

The COVID-19 restrictions have impacted people's lifestyles in all spheres (social, psychological, political, economic, and others). This study explored which factors affected the level of anxiety during the time of the first wave of COVID-19 and subsequent quarantine in a substantial proportion of 23 countries, included in this study. The data was collected from May to August 2020 (5 June 2020). The sample included 15,375 participants from 23 countries: (seven from Europe: Belarus, Bulgaria, Croatia, Hungary, Italy, Romania, Russia; 11 from West, South and Southeast Asia: Armenia, India, Indonesia, Iran, Iraq, Jordan, Malaysia, Pakistan, Saudi Arabia, Thailand, Turkey; two African: Nigeria and Tanzania; and three from North, South, and Central America: Brazil, Canada, United States). Level of anxiety was measured by means of the 7-item Generalized Anxiety Disorder Scale (GAD-7) and the 20-item first part of The State-Trait Anxiety Inventory (STAI)-State Anxiety Inventory (SAI). Respondents were also asked about their personal experiences with COVID-19, attitudes toward measures introduced by governments, changes in attitudes toward migrants during a pandemic, family income, isolation conditions, etc. The factor analysis revealed that four factors explained 45.08% of variance in increase of anxiety, and these components were interpreted as follows: (1) personal awareness of the threat of COVID-19, (2) personal reaction toward officially undertaken measures and attitudes to foreigners, (3) personal trust in official sources, (4) personal experience with COVID-19. Three out of four factors demonstrated strong associations with both scales of anxiety: high level of anxiety was significantly correlated with high level of personal awareness of the threat of COVID-19, low level of personal reaction toward officially undertaken measures and attitudes to foreigners, and high level of presence of personal experience with COVID-19. Our study revealed significant main effects of sex, country, and all four factors on the level of anxiety. It was demonstrated that countries with higher levels of anxiety assessed the real danger of a pandemic as higher, and had more personal experience with COVID-19. Respondents who trusted the government demonstrated lower levels of anxiety. Finally, foreigners were perceived as the cause of epidemic spread.

Relationship between parental consanguinity and digit ratios (2D:4D) among Turkish newborns in Sivas.

OBJECTIVES: The aim of this study was to investigate the effects of parental consanguinity on the 2D:4D digit ratio of newborn infants, whose parents were the first cousins. METHODS: The study included healthy and full-term newborn infants, delivered in a hospital, at the gestational ages from 37 to 41 weeks. A total of 225 newborns and their parents were included in the study. Of these 225 newborns; 100 were inbred and 125 were outbred infants. We used a Vernier caliper to measure the length of the second and fourth digits of the newborns (accuracy: 0.01 mm). RESULTS: Controlling for education and number of pregnancies, male newborns had lower digit ratios than female newborns, for both left and right hands. There were, moreover, differences between inbred and outbred samples. We determined that inbreeding was related to a reduction in the digit ratios regardless of the side of the hand and the sex of the infant, showing a consistent tendency to appear more masculine. Interaction between marriage type*sex was highly significant. CONCLUSIONS: Parental consanguinity appears to cause fetal masculinization of digit ratios by increasing fetal stress among Turkish newborns.

Prenatal exposure to oestrogens estimated by digit ratio (2d/4d) and breast size in young nulliparous women.

Digit ratio (2d/4d) in humans is commonly used as a proxy for the exposure to oestrogens and androgens in prenatal life. Masculinisation/feminisation in adults may be also related to digit ratio and therefore to the oestrogen/androgen ratio in prenatal life. It has been shown, for instance, that Waist-to-Hip ratio (WHR) and the amount and distribution of body fat are related to digit ratio in women. A species-specific, sexually dimorphic morphological trait in humans is also a pair of permanent breasts that develop during puberty, under the influence of oestrogens. Here we test if prenatal exposure to oestrogens (in relation to androgens), measured by digit ratio, may also be related to breast size in young, nulliparous women. 133 Turkish students (mean age 22.2) were measured. Breast size was calculated as the difference between breast and under-breast circumferences. We found that when controlling for body mass index (BMI), both right and left digit ratios correlate positively with breast size. This relationship is stronger for the digit ratio of the right hand, which confirms that this side is a better measure of sex differences. Thus, higher exposure to oestrogens in prenatal life is related with stronger expression of a sexually dimorphic trait, such as breast size, in adult women.

Self-reported aggressiveness is not related to developmental instability.

OBJECTIVE: In recent years, several researchers have focused on the relationship between fluctuating asymmetry and aggression. These studies reveal conflicting results. In this study, we examined the relationship between bodily symmetry and self-reported aggressive behavior in healthy young people living in Turkey. METHODS: The sample comprised of 100 male and 102 female university students recruited from Cumhuriyet University, Sivas. The Buss and Perry aggressiveness questionnaire was used. Four bilateral traits were measured for fluctuating asymmetry analysis. For the subsequent statistical analyses, only the composite asymmetry index was used. RESULTS: There was no relationship between composite asymmetry and any component of aggressiveness for either sex. CONCLUSIONS: Our findings for people living in Turkey did not support the hypothesis that aggressiveness, as a signal of evolutionary fitness, is related to developmental instability.

Growth and fluctuating asymmetry of human newborns: influence of inbreeding and parental education.

Historically, medical concerns about the deleterious effects of closely inbred marriages have focused on the risk posed by recessive Mendelian disease, with much less attention to developmental instability. We studied the effects of inbreeding (first-cousin marriage) on growth and fluctuating asymmetry of 200 full-term infants (101 inbred and 99 outbred) whose parents were of similar socioeconomic status in Sivas Province, Turkey. In addition to differences in their mean inbreeding coefficients (f = 1/16 for first cousins and f < 1/1,024 for unrelated parents), the consanguineous parents were less well educated (3 years, on average for both husbands and wives). We measured weight, height, head circumference, and chest circumference of the newborns, as well as four bilateral traits (ear width, ear length, and second and fourth digit lengths). After taking education into account, none of the measures of size (weight, height, head circumference, and chest circumference) and fluctuating asymmetry differed between the inbred and outbred groups. Male children of well-educated parents, however, were larger and had less fluctuating asymmetry. Female children of well-educated parents weighed more than those of less well-educated parents, but were otherwise indistinguishable for height, head circumference, chest circumference, and fluctuating asymmetry. We conclude that inbreeding depression causes neither an increase in fluctuating asymmetry of full-term newborns, nor a decrease in body size. Unmeasured variables correlated with education appear to have an effect on fluctuating asymmetry and size of male children and only a weak effect on size (weight) of female children.

Inbreeding is associated with lower 2D: 4D digit ratio.

OBJECTIVES: While consanguineous marriage has been shown to result in a small increase in risk of recessive Mendelian disorders among offspring, far less research has been conducted on the effects of inbreeding on complex traits. These effects, thought to result from increased developmental instability due to loss of heterozygosity, are expected to be found more pervasively than rare recessive Mendelian traits and are expected to result in increased developmental noise. Here, we test for a direct effect of inbreeding on 2D : 4D, a putative indicator of prenatal hormonal environment. METHODS: We compared the 2D : 4D ratios of 122 male and 108 female consanguineous (children of first cousin marriages) high school and university students to those of 142 male and 122 females controls. RESULTS: Across hands and sex, consanguineous parentage was consistently associated with lower, more masculine-typical, digit ratios. Digit ratios were 1.3-1.9 times more variable among the consanguineous group than the control group. While socio-economic status cannot explain the effects seen in our data, we found that lower, more masculinized, digit ratios were associated with lower family income. CONCLUSIONS: Our results suggest that consanguineous marriages are associated with a fetal environment that influences morphological development and may have associated behavioral sequelae.

Extreme behavioral lateralization and the remodeling of the distal humerus.

OBJECTIVES: The effects of extreme behavioral lateralization (i.e., extreme handedness) on the epicondylar breadth are poorly understood. This study was conducted in order to determine the effects of high levels of right- and left-handedness on epicondyle of the humerus. METHODS: Elbow width of 186 healthy male university students who completed their physical development (extreme left handed = 92, mean age = 18.67, SD = 0.61; extreme right handed = 94, mean age = 18.55, SD = 0.58) were measured with 0.01 mm sensitivity and Edinburgh Handedness Inventory was applied to determine the handedness of the individuals. Participants with scores of +100 were designated as extreme right-handers, and participants with scores of -100 were designed as extreme left-handers. RESULTS: According to the findings, the degree of directional asymmetry was +1.22 (SD = 2.24) in the extreme right handed, whereas in extreme left handed -0.59 (SD = 1.74). The relative deviation percentage in the extreme right handed was 3.1% whereas 2.2% in the extreme left handed. CONCLUSIONS: It could be stated that extreme handedness has an influence on the asymmetry of epicondyle of the humerus; nevertheless, this effect is more significant in the extreme right handed. This is likely to result from the necessity for left-handed people to adapt themselves to the conditions of a dominantly "right-handed" world.

Facial soft tissue thickness in individuals with different occlusion patterns in adult Turkish subjects.

Knowledge of variation in facial soft tissue thickness is important for forensic anthropologists, dentists, and plastic surgeons. Forensic anthropologists use such information as a guide in facial reconstruction and superimposition methods. The purpose of this study was to measure facial tissue thicknesses of adult males and females of Turkish origin across different types of occlusion, and to compare the results with each other and with values obtained for other populations. The study was conducted on 200 healthy individuals. The analysis of facial tissue thickness included 20 landmarks (10 dentoskeletal and 10 soft tissue) and 10 linear variables. Sex-based variation in facial tissue thickness was noted. The highest soft tissue thickness values were observed in the group with Class III occlusion type at Sn-A point for both the females (16.9, SD=2.4) and the males (17.8, SD=3.3). In the Class I group, the highest tissue depth was observed at Sn-A point (15.3, SD=2.1) in females, and at Li-Id point (17.1, SD=1.9) in males. In the Class II group, contrary to the findings for Class I, the highest soft tissue depth was at Li-Id point (16.0, SD=1.4) in females, and at Sn-A point (18.1, SD=2.6) in males. In conclusion, facial tissue thickness varied in adults depending on the sex and on the type of occlusion.

Relationship between shortness of final body height and fluctuating asymmetry in Turkish young males.

BACKGROUND: Body height is a versatile bio-indicator in that it reflects the quality of physical development. Fluctuating asymmetry, on the other hand, refers to small random deviations from perfect symmetry in bilaterally paired structures and is believed to reflect the ability of an organism to cope with genetic and environmental stresses during its development. AIM: This study sought to investigate the relationship between body height and fluctuating asymmetry in young adult males who display different height-development structures. SUBJECT AND METHODS: Height and eight bilateral non-facial traits were measured in a sample of 320 young male individuals from different socioeconomic backgrounds who display differences in height. Z-scores of each individual were calculated based on the age-range values indicated in the Center for Disease Control's (CDC) 2000 growth data of the US. RESULTS: The five measurements demonstrating fluctuating asymmetry indicate that there is a significant increase in fluctuating asymmetry that parallels the decrease in body height. Developmental stability increases with the increasing body height. CONCLUSION: This finding implies that the stresses causing slower growth in body height might have negative effects also on fluctuating asymmetry.

Does urban poverty increase body fluctuating asymmetry?

Perturbations during development leave enduring signs on the adult body. Fluctuating asymmetry (FA) is a good bio-indicator of stress during ontogeny. The aim of this study is to determine the effect of urban poverty on the fluctuating asymmetry of young Turkish males. Young males from a lower socioeconomic group (N = 140, Mean age = 18.17 +/- 0.61) were selected from slum areas of Ankara, the capital of Turkey, where urban poverty is intense. An upper socioeconomic group, on the other hand, consisted of students from two private colleges and included children from some of the richest families in Turkey (N = 120, Mean age = 18.08 +/- 0.54). Eight anthropometric traits of all subjects were measured. Considering the seven measurements demonstrate ideal FA, the individuals living in poor areas of the city displayed higher FA. The discrepancy between the two groups was even greater for a measure of composite FA. In conclusion, poor living conditions in Ankara, where urban poverty is intense, adversely impact the developmental stability of young Turkish males.

Tall men with medium body fat mass percentage display more developmental stability.

A symmetrical body may signal the ability of an individual to cope with developmental perturbations and may thus be considered a 'health certificate'. It is known that symmetrical men are considered more attractive by women and that their reproductive success is higher. This study examined the associations between measures of body structure and fluctuating asymmetry in young Turkish men. Weight, height, and bioelectrical impedance were measured in a sample of 250 men residing in Ankara (mean age=18.4, SD=0.6), and body mass index was calculated. Fluctuating asymmetry was measured using hand length, hand width, elbow width, wrist width, knee width, ankle width, foot length, foot width, ear length, and ear width. According to the obtained findings, there is a negative linear relationship between composite fluctuating asymmetry (CFA) and height, and a positive quadratic relationship between CFA and fat mass. These results might indicate that the tall Turkish men with medium body fat mass percentage display more developmental stability.

Fluctuating and directional asymmetry in young human males: effect of heavy working condition and socioeconomic status.

Many adverse environmental and genetic factors can affect stability of development during human growth. Although the level of fluctuating asymmetry (FA) may be influenced by environmental and genetic stress encountered during this period, directional asymmetry (DA) is largely attributable to differential mechanical loading during bone growth, for example, handedness. I assessed the effects of heavy working conditions and socioeconomic conditions on asymmetry levels in three groups of young human males: 1) individuals employed in the heavy industry sector (n = 104, mean age = 18.48 +/- 0.61 years), 2) individuals who had the same socioeconomic status as the laborers (n = 102, mean age = 18.39 +/- 0.58 years) but were not laborers, and 3) nonlaborers from the higher socioeconomic levels of society (n = 103, mean age = 18.43 +/- 0.67). For all subjects, hand length, hand width, elbow width, wrist width, knee width, ankle width, foot length, foot width, ear length, and ear width were measured. All measurements of the upper extremities in the labor group appeared to exhibit DA; in the other two groups only hand measurements exhibited DA. According to analysis of FA, subjects living in poor conditions exhibited more FA than their nonlaborer peers living in better conditions. In addition, biomechanical pressures due to heavy working conditions of the labor group appeared to cause increased DA in the upper extremities: DA increased with an increase in the number of years working.

Brief communication: Facial fluctuating asymmetry as a marker of sex differences of the response to phenotypic stresses.

Fluctuating asymmetry (FA) is thought to increase as a result of environmental perturbations during development. A number of studies involving measures of health and developmental stability other than FA have discussed the presumed increased buffering in females relative to males. But, there is little evidence in the literature on FA to support this hypothesis. This research was conducted to determine the level of difference in terms of facial FA between sexes under different environmental conditions. Group 1 included final year students from three high schools in Yenimahalle, a slum district of Ankara (males: N = 163, mean age = 17.55, sd = 0.50; females: N = 141, mean age = 17.48, sd = 0.38). Group 2 included students with higher socioeconomic background and was composed of final year students from three different private schools located in Cankaya (N = 171, mean age = 17.44, sd = 0.26; females: N = 152, mean age = 17.38, sd = 0.31). Digital images were used to assess the degree of facial asymmetry as measured from eight paired traits and calculated as a composite score. The study shows that the male students had higher facial asymmetry than the female students. However, the present difference reaches a significant level in the low-socioeconomic status group. As a result, it could be inferred that differences in developmental stability between sexes might emerge under stressful conditions.

Effect of inbreeding depression on growth and fluctuating asymmetry in Turkish young males.

This study sought to examine the effects of inbreeding on physical development and fluctuating asymmetry (FA). A total 144 male high-school students (mean age = 18.11 +/- 0.52) whose parents are first cousins (F = 0.125) of low-socioeconomic status and 146 male students (mean age = 18.08 +/- 0.54) from the same school who do not have any consanguineous parents (F = 0) were observed in Ankara. In addition to the weight and height measurements of the individuals, eight bilateral traits (hand width, elbow width, wrist width, knee width, ankle width, foot width, ear length, and ear width) were measured. Whereas the inbred group has lower values in terms of weight and height, the difference in body mass index between the groups is not significant. Although the inbred group is more asymmetric in terms of the observed bilateral traits, the differences are below the significance level. However, the composite FA index shows that the inbred group is more asymmetric and the difference is significant (P < 0.05). Inbreeding depression has a negative effect on weight and height development, and a negative effect on developmental stability.

Anthropometric characteristics of young Turkish male athletes.

Comparative reports on the anthropometric characteristics of athletes are certainly important in modern sports and have long been studied by sports scientists. Studies on Turkish athletes however, are limited. In the present study physical characteristics of athletes active in various sports (American football, basketball, volleyball and football) were observed and compared to each other and to those of non-athlete individuals. 153 volunteer male subjects participated in the study. All of the athletes were licensed members of teams in inter-university leagues. All subjects were given information about the objectives of the study and were advised of the manner with which the anthropometric measurements would be obtained. In addition to 17 anthropometric values, body mass index (BMI) and somatotype components were calculated and evaluated. Length, breadth, and girth values were evaluated by ANCOVA and height and weight were used as co-variate factors. The other variables were evaluated by metric and non-metric ANOVA. The results of the study indicate that basketball and volleyball players were characteristic with their longer lower limb length; American football players were with their wider biiliac breadth and higher girth values; and football players with their small structure. It was also observed that Turkish athletes have higher endomorphy and lower mesomorphy values when compared to athletes from other countries.

Biomechanical pressures and upper extremity asymmetry: a study on young laborers.

The purpose of this study is to reveal the impacts of biomechanical pressures of heavy working conditions on the upper extremities of young laborers. The study covers the examination of the upper extremities of 104 young laborers in the industrial workshops of Ankara, Turkey regarding bilateral asymmetry. The average age of the laborers was 18.48 +/- 0.61 years. The control group consisted of 102 non-laborers with an average age of 18.39 +/- 0.58 years. The laborers were measured with regard to width of elbows, wrists, and hands, and the length of hands. No significant difference between the groups was observed with the exception of average wrist width. However, while the labor group showed directional asymmetry in all measurements, the non-laborers exhibited directional asymmetry only in hand width and length. Consequently, the study revealed that biomechanical pressures tend to increase directional asymmetry in the upper extremities.

Body composition of young laborers: the results of a bioelectrical impedance analysis.

The aim of this study was to determine the changes caused by physical stress on the body composition of young males. In order to show these changes, the study was performed with 104 young male laborers who worked through their adolescence and who were currently working in workshops in the industrial sector (Group 1, mean age 18.48 +/- 0.61 years). For the control group, two groups of the same age but having a difference in terms of socioeconomic status were chosen. The first one of these was comprised of individuals who had the same socioeconomic status as the laborers (Group 2, n = 102, mean age 18.39 +/- 0.58 years) but were not laborers. The second control group was composed of individuals from the higher socioeconomic levels of society (Group 3, n = 103, mean age 18.43 +/- 0.67). Measurements of the height of the individuals were taken with a standard portable anthropometer, and their body weight and BIA measurements were taken with Tanita TBF-305 leg-to-leg body composition analysis equipment. The results of the analysis show that the weight, height, BMI and fat mass values of the laborers were significantly lower (P < 0.05-0.001) than those of Group 3, but were not statistically different from those of Group 2. These findings reveal that the effects of socioeconomic conditions on body composition outweigh those of working conditions.

Growth and nutritional status of male adolescent laborers in Ankara, Turkey.

Undernutrition, pathogenic agents, and poor living conditions are of primary importance in the evaluation of adverse environmental conditions' effects on human growth; but child labor (an equally significant factor, especially in underdeveloped countries) is generally overlooked or ignored. The aim of this study is to focus on this subject and clarify the effects of labor on the physical growth and nutritional status of child and adolescent laborers. In this study, the height and weight of 532 male adolescent laborers aged 13.5-18.5 years and their non-laboring peers (n = 451) (the control group) were measured by standard anthropometric techniques and equipment. The individuals of both groups come from lower socioeconomic strata and share similar living conditions. Data were transformed to z-scores, using the US Center for Disease Control and Prevention's 2000 growth charts. The analyses show that the z-scores for height-for-age, weight-for-age, and body mass index (BMI)-for-age were negative in both groups. The z-scores of laborers' height-for-age and weight-for-age values lie below the controls', but there is no significant difference between the two groups' BMI-for-age scores. In the laboring group, the percentages of stunting (-2 SD of height-for-age), underweight (-2 SD of weight-for-age), and wasting (-2 SD of BMI-for-age) were 14.3, 2.6, and 0.2, respectively. These values suggest that malnutrition is not a common problem among adolescent laborers living in Ankara; but laboring is an important cause of faltering in growth, particularly in linear growth, in less or underdeveloped economic environments.