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Banyeh M, Mayeem BN, Woli MK, Kolekang AS, Dagungong CB, Bure D, Wemegah RK, Azindow MI, Yakubu S, Seidu M, Baba MM, Essoun E, Owireduwaa N. Exploring Hematological and Biochemical Disparities in Same-Sex and Opposite-Sex Females: A Cross-Sectional Twin Study in a Ghanaian Population. Twin Res Hum Genet 2024; 27:50-55. [PMID: 38444332 DOI: 10.1017/thg.2024.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
There are sex-dependent differences in hematological and biochemical variables in adulthood attributed to the predominant effects of testosterone in males and estrogen in females. The Twin Testosterone Transfer (TTT) hypothesis proposes that opposite-sex females may develop male-typical traits due to exposure to relatively higher levels of prenatal testosterone than same-sex females. Additionally, prenatal testosterone exposure has been suggested as a correlate of current circulating testosterone levels. Consequently, opposite-sex females might exhibit male-typical patterns in their hematological and biochemical variables. Despite this hypothesis, routine laboratory investigations assign the same reference range to all females. Our cross-sectional study, conducted in Tamale from January to September 2022, included 40 twins, comprising 10 opposite-sex (OS) males (25%), 10 OS females (25%), and 20 same-sex (SS) females (50%), all aged between 18 and 27 years. Fasting venous blood samples were collected and analyzed using automated hematology and biochemistry laboratory analyzers. Results indicated that levels of hemoglobin, serum creatinine, gamma-glutamyl transferase, total protein, globulins, and total testosterone were significantly higher in OS males than OS females. Conversely, total cholesterol and low-density lipoprotein cholesterol were significantly higher in OS females than OS males. Unexpectedly, levels of low-density lipoprotein cholesterol and total testosterone were significantly higher in SS females than OS females. Contrary to expectations, opposite-sex females did not exhibit male-typical patterns in their hematological and biochemical variables. This suggests that the TTT effect may not occur or may not be strong enough to markedly affect hematological and biochemical variables in OS females.
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Affiliation(s)
- Moses Banyeh
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Benjamin N Mayeem
- Department of Medical Laboratory, Living Waters Hospital, Ejisu-krapa, Kumasi, Ghana
| | - Moses Kofi Woli
- Department of Medical Diagnostics, College of Health and Well-Being, Kintampo, Ghana
| | - Augusta S Kolekang
- Department of Epidemiology, Biostatistics and Disease Control, University for Development Studies, Tamale, Ghana
| | | | - David Bure
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Romarick Kofi Wemegah
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Mikail Ihsan Azindow
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Suleman Yakubu
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Musah Seidu
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Mohammed Madde Baba
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Elisha Essoun
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
| | - Nancy Owireduwaa
- Department of Biomedical Laboratory Science, University for Development Studies, Tamale, Ghana
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Banyeh M, Yeboah NA, Seidu L, Doglikuu AF. Sex estimation accuracies from variables of the index and ring fingers in a Ghanaian population: Absolute lengths versus length ratios. FORENSIC SCIENCE INTERNATIONAL: REPORTS 2022. [DOI: 10.1016/j.fsir.2022.100277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Lidborg LH, Cross CP, Boothroyd LG. A meta-analysis of the association between male dimorphism and fitness outcomes in humans. eLife 2022; 11:e65031. [PMID: 35179485 PMCID: PMC9106334 DOI: 10.7554/elife.65031] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 02/17/2022] [Indexed: 11/13/2022] Open
Abstract
Humans are sexually dimorphic: men and women differ in body build and composition, craniofacial structure, and voice pitch, likely mediated in part by developmental testosterone. Sexual selection hypotheses posit that, ancestrally, more 'masculine' men may have acquired more mates and/or sired more viable offspring. Thus far, however, evidence for either association is unclear. Here, we meta-analyze the relationships between six masculine traits and mating/reproductive outcomes (96 studies, 474 effects, N = 177,044). Voice pitch, height, and testosterone all predicted mating; however, strength/muscularity was the strongest and only consistent predictor of both mating and reproduction. Facial masculinity and digit ratios did not significantly predict either. There was no clear evidence for any effects of masculinity on offspring viability. Our findings support arguments that strength/muscularity may be sexually selected in humans, but cast doubt regarding selection for other forms of masculinity and highlight the need to increase tests of evolutionary hypotheses outside of industrialized populations.
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Affiliation(s)
- Linda H Lidborg
- Department of Psychology, Durham UniversityDurhamUnited Kingdom
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Butovskaya M, Burkova V, Apalkova Y, Dronova D, Rostovtseva V, Karelin D, Mkrtchyan R, Negasheva M, Batsevich V. Sex, population origin, age and average digit length as predictors of digit ratio in three large world populations. Sci Rep 2021; 11:8157. [PMID: 33854119 PMCID: PMC8046776 DOI: 10.1038/s41598-021-87394-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 03/25/2021] [Indexed: 02/06/2023] Open
Abstract
Recently, a number of authors have claimed that sexual dimorphism in the second-to-fourth digit ratio (2D:4D) is simply dependent on digit length and is an artifact of allometry. The goal of our study is to verify the validity of these assumptions. The study sample comprised 7,582 individuals (3,802 men and 3,780 women) from three large world populations: Europeans (n = 3043), East Africans (n = 2844), and Central Asians (n = 1695). The lengths of the second and fourth digits on both hands were measured. Digit ratios were computed according to standard procedures. Analyses were conducted separately for each hand for the whole sample and in succession for the three large populations. Additionally, we separately tested four age cohorts (≤ 13, 14-18, 19-30, and 31 ≥ years) to test the effect of developmental allometry. The second and fourth digits showed strong positive linear relationships on both hands, and demonstrated an increase with age; digit length in women from the youngest age cohort was longer or equal to that of men, and shorter than men in older age cohorts. However, the 2D:4D magnitude and its sexual dimorphism remained stable throughout the ontogeny. To test for an allometric effect on 2D:4D, the average digit lengths were calculated. Both sex and population origin were permanent reliable predictors of 2D:4D, whereas average digit length was not. Height was applied as another measure of allometric effect on the limited sample (≤ 30 years) from the European population, along with sex and age. No allometric effect was observed in this case. We conclude that sex differences in 2D:4D are not an artifact of allometry.
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Affiliation(s)
- Marina Butovskaya
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Leninsky pr., 32a, Moscow, Russia, 119991.
- National Research University Higher School of Economics, Moscow, Russia.
- Russian State University for the Humanities, Moscow, Russia.
| | - Valentina Burkova
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Leninsky pr., 32a, Moscow, Russia, 119991
- National Research University Higher School of Economics, Moscow, Russia
| | - Yulia Apalkova
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Leninsky pr., 32a, Moscow, Russia, 119991
| | - Daria Dronova
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Leninsky pr., 32a, Moscow, Russia, 119991
| | - Victoria Rostovtseva
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Leninsky pr., 32a, Moscow, Russia, 119991
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Kaczmarski M, Kaczmarek JM, Jankowiak Ł, Kolenda K, Tryjanowski P. Digit ratio in the common toad Bufo bufo: the effects of reduced fingers and of age dependency. ZOOLOGICAL LETTERS 2021; 7:5. [PMID: 33766147 PMCID: PMC7992345 DOI: 10.1186/s40851-021-00174-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
INTRODUCTION Despite the growing number of studies describing digit ratio patterns in tetrapods, knowledge concerning certain basic issues is still scarce. In lower vertebrates such as tailless amphibians (Anura), the numbering of individual fingers on the forelimbs and their homology with the fingers of other vertebrates pose an unsolved problem. Based on reviewed data on anuran limb development, we argue that the correct finger numbering scheme should be based on the assumption that the first finger, not the fifth finger, was reduced on the forelimbs. We analyzed the digit ratio in the common toad (Bufo bufo, Bufonidae), a species characterized by well-developed sexual dimorphism whereby females are larger than males, using both numbering schemes present in the literature. RESULTS We found that the digit ratio on hindlimbs differed significantly between the sexes only in the cases of left 2D:3D, with lower digit ratios in females, and of left 3D:4D, with lower digit ratios in males. We found that sex was the only significant variable for forelimbs, differentiating 2D:3D on the left forelimb, with lower digit ratios in females; 2D:4D on the right forelimb, with lower digit ratios in males; and 3D:4D on both forelimbs, with lower digit ratios in males. These results relate to variant II reflecting the hypothesis that the first digit was reduced during phylogenesis. There was no relationship between the body size (SVL) of individuals and any digit ratio, excluding 2D:4D on the right forelimbs in models with age variables. Additionally, for a subset of data where individual age was known, the models indicated that age was linked to significant differences in 2D:4D and 3D:4D on the left hindlimbs, while age, SVL, and sex influenced 2D:4D on the right forelimbs. CONCLUSION We emphasize the importance of the problem of the correct numbering of forelimb digits in Anura and, under the assumption that it was the fifth digit that was reduced, argue that earlier results on digit ratio in this group should be interpreted with caution. The detected relationship between digit ratio and age in amphibians expands our knowledge, indicating that the age of individuals should be included in future digit ratio studies. This relationship may also apply to studies using digit ratio as a noninvasive indicator of endocrine disruption in amphibians.
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Affiliation(s)
- Mikołaj Kaczmarski
- Institute of Zoology, Poznań University of Life Sciences, Wojska Polskiego 71c, PL 60-625 Poznań, Poland
| | - Jan M. Kaczmarek
- Institute of Zoology, Poznań University of Life Sciences, Wojska Polskiego 71c, PL 60-625 Poznań, Poland
| | - Łukasz Jankowiak
- Institute of Biology, University of Szczecin, Wąska 13, PL 71-415 Szczecin, Poland
| | - Krzysztof Kolenda
- Amphibian Biology Group, Department of Evolutionary Biology and Conservation of Vertebrates, Institute of Environmental Biology, University of Wrocław, Sienkiewicza 21, PL 50-335 Wrocław, Poland
| | - Piotr Tryjanowski
- Institute of Zoology, Poznań University of Life Sciences, Wojska Polskiego 71c, PL 60-625 Poznań, Poland
- Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Prague 6, Czech Republic
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Kowal M, Sorokowski P, Żelaźniewicz A, Nowak J, Orzechowski S, Żurek G, Żurek A, Juszkiewicz A, Wojtycka L, Sieniuć W, Poniatowska M, Tarnowska K, Kowalska K, Drabik K, Łukaszek P, Krawczyk K, Stefaniak T, Danek N. No relationship between the digit ratios (2D:4D) and salivary testosterone change: Study on men under an acute exercise. Sci Rep 2020; 10:10068. [PMID: 32572079 PMCID: PMC7308391 DOI: 10.1038/s41598-020-66915-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 03/16/2020] [Indexed: 01/08/2023] Open
Abstract
The digit ratio (2D:4D) is said to be a potential marker of exposure to prenatal sex steroids. Some studies suggest that the 2D:4D is also linked with the testosterone response to challenging situations due to organizational effect of prenatal hormonal milieu on adult endocrine functioning. However, up to date, there were only four studies (conducted on small samples) that examined the 2D:4D and the testosterone response to a challenging situation (i.e. physical exertion or aggressive context). Here, we examined the relationship between the 2D:4D and the testosterone change under an acute exercise among 97 men. We found that the digit ratios (the right 2D:4D, the left 2D:4D, and the right minus left 2D:4D) were neither predictors of pre-exercise testosterone, nor the change in testosterone level after a cycling task. Our results add a contradictory to previous studies evidence in a discussion on the links of the 2D:4D and the testosterone change.
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Affiliation(s)
- Marta Kowal
- Institute of Psychology, University of Wrocław, Wrocław, Poland
| | - Piotr Sorokowski
- Institute of Psychology, University of Wrocław, Wrocław, Poland.
| | | | - Judyta Nowak
- Department of Human Biology, University of Wrocław, Wrocław, Poland
| | | | - Grzegorz Żurek
- University School of Physical Education in Wrocław, Wrocław, Poland
| | - Alina Żurek
- Institute of Psychology, University of Wrocław, Wrocław, Poland
| | | | - Lidia Wojtycka
- Institute of Psychology, University of Wrocław, Wrocław, Poland
| | | | | | | | - Kaja Kowalska
- Institute of Psychology, University of Wrocław, Wrocław, Poland
| | | | | | | | | | - Natalia Danek
- University School of Physical Education in Wrocław, Wrocław, Poland
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Butovskaya M, Marczak M, Misiak M, Karelin D, Białek M, Sorokowski P. Approach to Resource Management and Physical Strength Predict Differences in Helping: Evidence From Two Small-Scale Societies. Front Psychol 2020; 11:373. [PMID: 32269535 PMCID: PMC7110700 DOI: 10.3389/fpsyg.2020.00373] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 02/18/2020] [Indexed: 01/16/2023] Open
Abstract
Helping behavior is likely to have evolved to increase chances of survival of an individual and their group. Nevertheless, populations differ significantly in their eagerness to help, and little is known about populational and inter-individual determinants of these differences. Previous studies indicated that economic and physiological factors might influence helping behavior. The aim of the present study was to investigate the effects of approach to resource management of a society (immediate-return economy vs. delayed-return economy), prenatal androgenization (based on second-to-fourth digit ratio), and physical strength (based on hand grip strength) on helping behavior toward others. Helping was assessed in terms of both general eagerness to help and differential helping toward: (1) kin, (2) other group members indiscriminately, (3) friends, and (4) those from whom help was obtained in the past. Based on data collected in two small-scale societies (n = 306), we found that people in the egalitarian immediate-return society (the Hadza hunter-gatherers of Tanzania) displayed helping behavior significantly more often than people in a more stratified delayed-return economy (Yali horticulturalists of Papua). Additionally, our results revealed that physical strength was a significant predictor of helping behavior in women but not in men. We discuss our findings in the light of the adaptive value of helping behavior.
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Affiliation(s)
- Marina Butovskaya
- Institute of Ethnology and Anthropology, RAS, Moscow, Russia.,National Research University Higher School of Economics, Moscow, Russia
| | - Michalina Marczak
- Institute of Psychology, University of Wrocław, Wrocław, Poland.,Institute of Psychology, Norwegian University of Science and Technology, Trondheim, Norway
| | - Michał Misiak
- Institute of Psychology, University of Wrocław, Wrocław, Poland
| | | | - Michał Białek
- Institute of Psychology, University of Wrocław, Wrocław, Poland
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Abstract
Although many studies show cultural or ecological variability in moral judgments, cross-cultural responses to the trolley problem (kill one person to save five others) indicate that certain moral principles might be prevalent in human populations. We conducted a study in a traditional, indigenous, non-Western society inhabiting the remote Yalimo valley in Papua, Indonesia. We modified the original trolley dilemma to produce an ecologically valid "falling tree dilemma." Our experiment showed that the Yali are significantly less willing than Western people to sacrifice one person to save five others in this moral dilemma. The results indicate that utilitarian moral judgments to the trolley dilemma might be less widespread than previously supposed. On the contrary, they are likely to be mediated by sociocultural factors.
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Butovskaya M, Burkova V, Karelin D, Filatova V. The association between 2D:4D ratio and aggression in children and adolescents: Cross-cultural and gender differences. Early Hum Dev 2019; 137:104823. [PMID: 31330462 DOI: 10.1016/j.earlhumdev.2019.07.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Two recent meta-analyses have suggested the association between digit ratio (2D:4D) and aggression is weak. This conclusion has been criticised because the meta-analyses conflate forms of aggression that show strong sex differences with those that do not, and most studies have considered post-pubertal participants. AIMS We test the influence of 2D:4D and ethnicity in the expression of aggression in children and adolescents in four ethnic groups of European and African origin. STUDY DESIGN Buss and Perry aggression questionnaire. Direct measurement of the 2nd and 4th digits. SUBJECTS 1296 children and adolescents from Tanzania and Russia from 4 ethnic groups - Datoga, Meru, Russians, Tatars. RESULTS There were ethnic and gender differences in ratings on aggression with boys consistently reporting more physical aggression. In all four samples right 2D:4D was significantly lower in boys, compared to girls. With regard to our total sample of boys, the right 2D:4D was significantly and negatively associated with self-ratings on physical aggression, but no association was found for left 2D:4D. No associations between 2D:4D and physical aggression were found for girls. Hostility was negatively correlated with 2D:4D for boys, and anger was positively correlated with 2D:4D in girls. CONCLUSION Sex differences were strongest for right 2D:4D (boys<girls), and for physical aggression (boys>girls). Right 2D:4D was negatively related to physical aggression in boys only, suggesting possible relationship to prenatal androgenization.
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Affiliation(s)
- M Butovskaya
- Russian State University for the Humanities, Moscow, Russia; Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russia; National Research University Higher School of Economics, Moscow, Russia.
| | - V Burkova
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russia
| | - D Karelin
- Institute of Geography, Russian Academy of Sciences, Moscow, Russia
| | - V Filatova
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russia
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Misiak M, Butovskaya M, Oleszkiewicz A, Sorokowski P. Digit ratio and hand grip strength are associated with male competition outcomes: A study among traditional populations of the Yali and Hadza. Am J Hum Biol 2019; 32:e23321. [PMID: 31512345 DOI: 10.1002/ajhb.23321] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 08/17/2019] [Accepted: 08/28/2019] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVES Indirect measures of physiological features, such as digit ratio and hand grip strength (HGS), are associated with the outcome of male competition activities. However, most of the studies were conducted in developed and industrialized societies. We tested the hypothesis that both digit ratio and HGS are associated with performance in male-specific activities in two traditional preindustrial societies: Yali and Hadza. METHODS To measure masculine behavioral traits, we determined warriorship status (Yali; n = 49) and assessed hunting skills (Yali n = 47 and Hadza n = 49). We also assessed the digit ratio and HGS of each male. We conducted our analyses using the Bayesian approach. RESULTS Bayesian regression models indicated that greater hand grip strength is associated with better hunting outcomes among Hadza males. We did not find a similar link for the Yali. We found anecdotal evidence for the link between left hand digit ratio and the number of birds hunted by Hadza. We found no evidence for the link between digit ratio and performance in male-male competition. CONCLUSIONS Our results suggest that male-male competition outcomes are determined by upper body strength, but only in the Hadza population. We also found limited support for the hypothesis that digit ratio is associated with hunting success among the Hadza. We found no support for the hypothesis concerning the digit ratio or HGS among the Yali. Our research provides partial support for the evolutionary hypotheses based on studies conducted in industrialized populations.
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Affiliation(s)
- Michał Misiak
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wroclaw, Wroclaw, Poland
| | - Marina Butovskaya
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow, Russia
| | - Anna Oleszkiewicz
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wroclaw, Wroclaw, Poland.,Department of Otorhinolaryngology, Smell and Taste Clinic, Dresden, Germany
| | - Piotr Sorokowski
- Faculty of Historical and Pedagogical Sciences, Institute of Psychology, University of Wroclaw, Wroclaw, Poland
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Králík M, Hupková A, Zeman T, Hložek M, Hlaváček L, Slováčková M, Čuta M, Urbanová P. Family effects on the digit ratio (2D:4D): The role of the interbirth interval. Am J Hum Biol 2019; 31:e23260. [PMID: 31183942 DOI: 10.1002/ajhb.23260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 02/26/2019] [Accepted: 05/12/2019] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES Family represents the closest social environment that immediately affects human ontogeny from an early prenatal period. This study aimed to assess sibship influences on the second-to-fourth digit length ratio (2D:4D ratio). METHODS The source sample represented 329 children aged 6.5 to 15.8 years (Czech Republic), including a subsample of 75 sibling pairs. A combination of (a) between-family design (cross-sectional sample) and (b) within-family design (pairs of siblings) was used to study the effect of family variables and interbirth interval (IBI) on the 2D:4D ratio. RESULTS Birth order, number of siblings (except for younger sisters), and sex ratio in siblings were significantly related to the 2D:4D ratio on the right, left, or both hands. At the same time, the relationships were opposite in males and females for birth order, number of older brothers and number of children in the family--increasing values in these variables increased digit ratio in males but decreased digit ratio in females. Mean difference in 2D:4D ratio (DIFF) within pairs (older minus younger sibling) differed from zero only in the "older sister--younger brother" group, where DIFF did not depend on IBI. On the contrary, in remaining pair types the DIFF tended to change with IBI, the strongest in the "older brother--younger sister" pairs. CONCLUSIONS Family variables, especially number of older brothers, should be considered as important confounding factors in 2D:4D ratio studies. However, the effect of these variables might be modified by IBI.
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Affiliation(s)
- Miroslav Králík
- Laboratory of Morphology and Forensic Anthropology (LaMorFA), Department of Anthropology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Adela Hupková
- Laboratory of Morphology and Forensic Anthropology (LaMorFA), Department of Anthropology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Tomáš Zeman
- Laboratory of Neurobiology and Molecular Psychiatry, Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Martin Hložek
- Department of Archaeology and Museology, Faculty of Arts, Masaryk University, Brno, Czech Republic
| | - Lukáš Hlaváček
- Palacký University Olomouc, Conference Services, Olomouc, Czech Republic
| | - Marie Slováčková
- Laboratory of Morphology and Forensic Anthropology (LaMorFA), Department of Anthropology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Martin Čuta
- Laboratory of Morphology and Forensic Anthropology (LaMorFA), Department of Anthropology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Petra Urbanová
- Laboratory of Morphology and Forensic Anthropology (LaMorFA), Department of Anthropology, Faculty of Science, Masaryk University, Brno, Czech Republic
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