Validation of the Short Version (TLS-15) of the Triangular Love Scale (TLS-45) across 37 Languages.

Love is a phenomenon that occurs across the world and affects many aspects of human life, including the choice of, and process of bonding with, a romantic partner. Thus, developing a reliable and valid measure of love experiences is crucial. One of the most popular tools to quantify love is Sternberg's 45-item Triangular Love Scale (TLS-45), which measures three love components: intimacy, passion, and commitment. However, our literature review reveals that most studies (64%) use a broad variety of shortened versions of the TLS-45. Here, aiming to achieve scientific consensus and improve the reliability, comparability, and generalizability of results across studies, we developed a short version of the scale-the TLS-15-comprised of 15 items with 5-point, rather than 9-point, response scales. In Study 1 (N = 7,332), we re-analyzed secondary data from a large-scale multinational study that validated the original TLS-45 to establish whether the scale could be truncated. In Study 2 (N = 307), we provided evidence for the three-factor structure of the TLS-15 and its reliability. Study 3 (N = 413) confirmed convergent validity and test-retest stability of the TLS-15. Study 4 (N = 60,311) presented a large-scale validation across 37 linguistic versions of the TLS-15 on a cross-cultural sample spanning every continent of the globe. The overall results provide support for the reliability, validity, and cross-cultural invariance of the TLS-15, which can be used as a measure of love components-either separately or jointly as a three-factor measure.

Exploring Attitudes Toward "Sugar Relationships" Across 87 Countries: A Global Perspective on Exchanges of Resources for Sex and Companionship.

The current study investigates attitudes toward one form of sex for resources: the so-called sugar relationships, which often involve exchanges of resources for sex and/or companionship. The present study examined associations among attitudes toward sugar relationships and relevant variables (e.g., sex, sociosexuality, gender inequality, parasitic exposure) in 69,924 participants across 87 countries. Two self-report measures of Acceptance of Sugar Relationships (ASR) developed for younger companion providers (ASR-YWMS) and older resource providers (ASR-OMWS) were translated into 37 languages. We tested cross-sex and cross-linguistic construct equivalence, cross-cultural invariance in sex differences, and the importance of the hypothetical predictors of ASR. Both measures showed adequate psychometric properties in all languages (except the Persian version of ASR-YWMS). Results partially supported our hypotheses and were consistent with previous theoretical considerations and empirical evidence on human mating. For example, at the individual level, sociosexual orientation, traditional gender roles, and pathogen prevalence were significant predictors of both ASR-YWMS and ASR-OMWS. At the country level, gender inequality and parasite stress positively predicted the ASR-YWMS. However, being a woman negatively predicted the ASR-OMWS, but positively predicted the ASR-YWMS. At country-level, ingroup favoritism and parasite stress positively predicted the ASR-OMWS. Furthermore, significant cross-subregional differences were found in the openness to sugar relationships (both ASR-YWMS and ASR-OMWS scores) across subregions. Finally, significant differences were found between ASR-YWMS and ASR-OMWS when compared in each subregion. The ASR-YWMS was significantly higher than the ASR-OMWS in all subregions, except for Northern Africa and Western Asia.

Body proportions according to stature groups in elite athletes.

The aim of this study was to investigate whether body proportions change as stature increases in elite Spanish athletes. The sample includes a total of 2,030 participants, comprised of 1,357 adult males, and 673 adult females. The male athletes were classified into five groups by stature, and the female athletes were classified separately into four stature groups. Ten anthropometric measurements were collected, and eleven body proportions were calculated. The body proportions with significant differences between stature groups in males were relative arm length (0.53-1.60%), relative forearm length (0.69-2.08%), relative thigh length (1.17-1.56%), relative tibial length (1.37-6.39%), cormic index (-0.94 - -4.49%), Manouvrier index (1.60-9.60%), and crural index (1.05-4.79%). In females, the body proportions with significant differences were relative forearm length (1.43%), relative thigh length (1.94-3.88%), relative tibial length (2.74-4.56%), cormic index (-0.74 - -3.72%), and Manouvrier index (1.97-8.71%). The distal parts of the upper and lower limbs increase proportionally as stature increases, whereas relative hand and foot lengths, which are the most distal parts of the extremities, remain constant in elite athletes.

Sex differences in human mate preferences vary across sex ratios.

A wide range of literature connects sex ratio and mating behaviours in non-human animals. However, research examining sex ratio and human mating is limited in scope. Prior work has examined the relationship between sex ratio and desire for short-term, uncommitted mating as well as outcomes such as marriage and divorce rates. Less empirical attention has been directed towards the relationship between sex ratio and mate preferences, despite the importance of mate preferences in the human mating literature. To address this gap, we examined sex ratio's relationship to the variation in preferences for attractiveness, resources, kindness, intelligence and health in a long-term mate across 45 countries (n = 14 487). We predicted that mate preferences would vary according to relative power of choice on the mating market, with increased power derived from having relatively few competitors and numerous potential mates. We found that each sex tended to report more demanding preferences for attractiveness and resources where the opposite sex was abundant, compared to where the opposite sex was scarce. This pattern dovetails with those found for mating strategies in humans and mate preferences across species, highlighting the importance of sex ratio for understanding variation in human mate preferences.

Sex Differences in Mate Preferences Across 45 Countries: A Large-Scale Replication.

Considerable research has examined human mate preferences across cultures, finding universal sex differences in preferences for attractiveness and resources as well as sources of systematic cultural variation. Two competing perspectives-an evolutionary psychological perspective and a biosocial role perspective-offer alternative explanations for these findings. However, the original data on which each perspective relies are decades old, and the literature is fraught with conflicting methods, analyses, results, and conclusions. Using a new 45-country sample (N = 14,399), we attempted to replicate classic studies and test both the evolutionary and biosocial role perspectives. Support for universal sex differences in preferences remains robust: Men, more than women, prefer attractive, young mates, and women, more than men, prefer older mates with financial prospects. Cross-culturally, both sexes have mates closer to their own ages as gender equality increases. Beyond age of partner, neither pathogen prevalence nor gender equality robustly predicted sex differences or preferences across countries.

Piecewise regression equations for estimating stature: an anthropometric study in Spanish females.

In forensic anthropology, generic equations are generally preferred for estimation of stature. However, recent studies have demonstrated that regression equations specific to stature groups yield more accurate predictions. Almost all previous studies have been conducted on male subjects, and it is not currently known how well such equations work for females. Therefore, this study aims to test whether regression equations specific to stature groups work for females as well. To this end, a cross-sectional study was conducted to estimate stature on a sample of 351 Spanish adult females. The participants were randomized into a calibration group (n = 185) and a validation group (n = 166). Equations for stature estimation based on tibial length were developed in the calibration group, which was categorized according to stature (short, medium, and tall) using the 15th and 85th percentiles as cut-off points. The standard errors of the estimations (SEEs) for the group-specific regression equations (SEE = 2.35-2.66 cm) were lower than for the general formula derived for all participants of the calibration group (SEE = 3.46 cm). The specific equations resulted in smaller differences between estimated and recorded statures than the generic equation when we tested the equations with the validation group. Additionally, the SEE values of the stature-specific equations are lower compared to generic equations applied to other human populations. In conclusion, the group-specific equations from tibial length have high accuracy compared with previously derived equations for Spanish females and other populations. This procedure for estimating stature thereby improves the tools available to forensic scientists.

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.

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.

Modernization, collectivism, and gender equality predict love experiences in 45 countries.

Recent cross-cultural and neuro-hormonal investigations have suggested that love is a near universal phenomenon that has a biological background. Therefore, the remaining important question is not whether love exists worldwide but which cultural, social, or environmental factors influence experiences and expressions of love. In the present study, we explored whether countries' modernization indexes are related to love experiences measured by three subscales (passion, intimacy, commitment) of the Triangular Love Scale. Analyzing data from 9474 individuals from 45 countries, we tested for relationships with country-level predictors, namely, modernization proxies (i.e., Human Development Index, World Modernization Index, Gender Inequality Index), collectivism, and average annual temperatures. We found that mean levels of love (especially intimacy) were higher in countries with higher modernization proxies, collectivism, and average annual temperatures. In conclusion, our results grant some support to the hypothesis that modernization processes might influence love experiences.

Universality of the Triangular Theory of Love: Adaptation and Psychometric Properties of the Triangular Love Scale in 25 Countries.

The Triangular Theory of Love (measured with Sternberg's Triangular Love Scale - STLS) is a prominent theoretical concept in empirical research on love. To expand the culturally homogeneous body of previous psychometric research regarding the STLS, we conducted a large-scale cross-cultural study with the use of this scale. In total, we examined more than 11,000 respondents, but as a result of applied exclusion criteria, the final analyses were based on a sample of 7332 participants from 25 countries (from all inhabited continents). We tested configural invariance, metric invariance, and scalar invariance, all of which confirmed the cultural universality of the theoretical construct of love analyzed in our study. We also observed that levels of love components differ depending on relationship duration, following the dynamics suggested in the Triangular Theory of Love. Supplementary files with all our data, including results on love intensity across different countries along with STLS versions adapted in a few dozen languages, will further enable more extensive research on the Triangular Theory of Love.

Affective Interpersonal Touch in Close Relationships: A Cross-Cultural Perspective.

Interpersonal touch behavior differs across cultures, yet no study to date has systematically tested for cultural variation in affective touch, nor examined the factors that might account for this variability. Here, over 14,000 individuals from 45 countries were asked whether they embraced, stroked, kissed, or hugged their partner, friends, and youngest child during the week preceding the study. We then examined a range of hypothesized individual-level factors (sex, age, parasitic history, conservatism, religiosity, and preferred interpersonal distance) and cultural-level factors (regional temperature, parasite stress, regional conservatism, collectivism, and religiosity) in predicting these affective-touching behaviors. Our results indicate that affective touch was most prevalent in relationships with partners and children, and its diversity was relatively higher in warmer, less conservative, and religious countries, and among younger, female, and liberal people. This research allows for a broad and integrated view of the bases of cross-cultural variability in affective touch.

Stature estimation based on tibial length in different stature groups of Spanish males.

It is well-known that secular trends affect human stature and constitution, and this fact should be taken into consideration in forensic anthropology, especially in stature estimation. Recently, stature-group-specific equations have been developed to take into account these variations. The aim of the present study is to estimate living stature according to tibial length in different stature groups in a sample of Spanish adult males in order to improve the accuracy of previous equations. A cross-sectional study was conducted on a sample of 495 Spanish Caucasian participants who were randomized into two groups, the study group with 249 participants and the cross-validation group with 246 participants. Specific equations were obtained according to stature groups using the 15th and 85th percentiles as cut off points. The results showed that the coefficient of determination (R2) and standard error of estimation (SEE) were lower with the specific equations based on stature groups (R2=0.22-0.57; SEE=2.12-2.66cm) than the equation with all participants of the study group (R2 = 0.77; SEE=3.29cm). The equations were tested in the cross-validation group, whose results showed more accuracy in the equations for a stature <185.9cm (i.e., in people with short and medium statures). In conclusion, the stature-group-specific equations based on tibial lengths of Spanish adult males are more accurate for stature estimation than other equations that have been formulated in the Spanish population. In forensic settings, it is recommended to use regression equations specific to stature groups when estimating stature.

Contrasting Computational Models of Mate Preference Integration Across 45 Countries.

Humans express a wide array of ideal mate preferences. Around the world, people desire romantic partners who are intelligent, healthy, kind, physically attractive, wealthy, and more. In order for these ideal preferences to guide the choice of actual romantic partners, human mating psychology must possess a means to integrate information across these many preference dimensions into summaries of the overall mate value of their potential mates. Here we explore the computational design of this mate preference integration process using a large sample of n = 14,487 people from 45 countries around the world. We combine this large cross-cultural sample with agent-based models to compare eight hypothesized models of human mating markets. Across cultures, people higher in mate value appear to experience greater power of choice on the mating market in that they set higher ideal standards, better fulfill their preferences in choice, and pair with higher mate value partners. Furthermore, we find that this cross-culturally universal pattern of mate choice is most consistent with a Euclidean model of mate preference integration.

Growth patterns and physical plasticity in adolescent laborers.

Data about the effects of working environment and excessive physical loads on human growth and constitution are insufficient. Although there are a few studies which link growth retardation in children's stature and long bones to their exposure to hard labor, it is difficult to discern whether the detrimental effects of compressive forces on growth result solely from severe compressive stresses or from the subjects' poor economic and substandard nutritional conditions as well. The aim of this study was to clarify this issue by comparing the anthropometric dimensions of laboring and non-laboring adolescents; both groups came from lower socioeconomic strata and were subject to poor living conditions. The laboring group consisted of 532 male apprentices aged 13.5-18.5, and the control group, of their 451 non-laboring peers who were attending school during the period of observation. Body weight, 3 vertical dimensions (stature, upper and lower limb lengths), 2 diameters (elbow and knee breadths), and 3 circumferences (contracted and relaxed upper arm girth and calf girth) were measured. In addition, relative growth according to the body height for each variable was computed, since relative variables are more valuable in evaluating the effects of excessive loading on the human body. The analyses showed that all vertical dimensions of laboring adolescents lagged behind those of their non-laboring peers. There were also clear differences between the two groups with regard to relative diameters and girths. The pressure effects of physical activity stimulate the transversal growth of the long bones. Similarly, circumferences, especially contracted upper arm girth relative to stature, are more developed in the laboring group than in the non-laboring group. These findings suggest that excessive workloads retard adolescents' vertical growth, especially in upper parts of the body, but that they stimulate transversal growth of the long bones and muscle development.

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.

The ultrastructural alterations in rat corneas with experimentally-induced diabetes mellitus.

OBJECTIVE: To examine the ultrastructural changes of rat corneas in streptozotocin (STZ) induced diabetes mellitus and the follow-up insulin treatment. METHODS: Sprague-Dawley type rats was used for experimental procedures during the period from January to April 2003 at Baskent University, Ankara, Turkey. Rats were studied in 4 groups; group 1: controls, group 2: sham controls (single dose IV sodium citrate), group 3: STZ-induced diabetes mellitus (single dose 45 mg/kg STZ intravenously), group 4: diabetes mellitus + insulin treatment (8 U/day). RESULTS: We observed degenerative changes in the epithelial layer, stromal keratocytes and endothelial cells in diabetic group. In contrast, the corneal layers have revealed positive alterations in the insulin-treated group. The statistical analyses showed significant narrowing in the epithelial layer in the diabetic group (p=0.002), whereas thickening was observed in the epithelial basement membrane and Descemet's membrane (p=0.002). CONCLUSION: It was determined that diabetes mellitus causes degenerative changes in cornea, which are positively influenced by short-term insulin treatment.

Body height estimation based on dimensions of sacral and coccygeal vertebrae.

This study is to evaluate whether it is possible to predict living stature from sacral and coccygeal vertebral dimensions. Individual vertebral body heights, sacral height (SH), and sacrococcygeal height (SCH) were recorded from the magnetic resonance images of 42 adult males. Sum of the heights of five sacral vertebrae (sigmaS), the first four coccygeal vertebrae (sigmaC), and the total height of the sacral and the first four coccygeal vertebrae together (sigmaSC) were also recorded. Linear regression equations for stature estimation were produced using the above mentioned variables. The regression equations were constructed and tested by using jack-knife procedure. Statistical analyses indicated that the combined variables (SH, SCH, sigmaS, sigmaC, sigmaSC) were more accurate predictors of stature than the heights of individual vertebrae. The results of the study pointed out that the equations derived from sacrococcygeal dimensions perform somewhat better than ones based on foot and head variables, but worse than those based on long-bone length. As a conclusion, the dimensions of sacral and coccygeal vertebrae could be used for stature estimation when long bones are not available.