A twin registry study of male and female sexual orientation
•Download as DOC, PDF•
1 like•463 views
This document summarizes a journal article that reports on a twin registry study of male and female sexual orientation. The study evaluated the influence of heredity on sexual orientation by comparing concordance rates of sexual orientation in monozygotic and dizygotic twins. The results from this and prior twin studies generally suggest some genetic influence on sexual orientation, though the degree of influence varies across studies. The study reported the highest concordance rates among monozygotic twins compared to dizygotic twins.
Report
Share
Report
Share
Recommended
Integr. Comp. Biol.-2016-Burns-icb-icw017
This document summarizes a symposium presentation on the study of male reproductive morphology across different ecological conditions in five species of Japanese harvestmen. The researchers analyzed reproductive organs from populations that varied in elevation, latitude, and observed male-to-female sex ratios. They found that penis length decreased with increasing latitude, supporting the idea of physiological constraints in marginal habitats. Males from parthenogenetic species with female-biased populations had traits that may enhance precopulatory clasping ability compared to males from species with more even sex ratios. The findings suggest long-term sex ratio biases can influence the evolution of primary and secondary reproductive morphology.
Genetics aggression
1. Researchers study genetic factors related to aggressive behavior using twin and adoption studies to separate genetic and environmental influences. Twin studies compare rates of aggression in monozygotic (identical) twins who share all genes versus dizygotic (fraternal) twins who share about 50% of genes.
2. Meta-analyses of twin and adoption studies suggest genetics can account for around 50% of the variability in aggressive behavior, though the environment also plays a role.
3. While early research linked traits like the XYY genotype to increased aggression, later studies found no single genetic characteristic was associated with aggression, suggesting the initial genetic views of aggression were overemphasized.
Lucy donaldson
This document summarizes a study examining the relationship between linear enamel hypoplasias (LEHs) and adult stature in human skeletal remains from St. Gregory's Priory Cemetery in Canterbury, UK dating to the medieval period. The study found statistically significant relationships between LEHs and stature that differed between males and females. Females who experienced growth disruptions earlier in life tended to be taller, while males who experienced disruptions later were taller. The number of LEHs was also positively correlated with male stature. The results suggest early life stress can have a small impact on maximal adult height.
Variation and causes of variation
Assignment of Animal Breeding
By 16th Batch of Bsc.Ag 6th Semester
Roll No. 21-40
on Variation and Causes of Variation
Disseration Proposal
This document summarizes a proposed study that aims to examine the relationship between athletic participation and sexual aggression in college men. Specifically, it aims to determine if factors like masculinity, competitiveness, and sense of sexual entitlement can explain the reported association between athletics and sexual aggression. The study will survey male college wrestlers and non-athletes on measures of sexual experiences, masculinity, competitiveness, and sexual entitlement. It will analyze the relationships between these variables and test if the association between athletics and sexual aggression remains significant when accounting for masculinity-related factors. The findings could help inform intervention programs targeting populations at risk of sexual aggression.
Gosling
This document discusses a panel on animal personality research. It includes the chairs and presenters, which focus on using animal models like monkeys and fish to better understand the biological, genetic, and environmental bases of personality. The research aims to examine how personality may impact health, how personality can change over the lifespan, and help answer fundamental open questions about the nature and origins of personality.
Mehta & Strough_2009_ Sex segregation across the lifespan
This document summarizes research showing that sex segregation, or the separation of individuals into same-sex groups, persists across the lifespan rather than just being a childhood phenomenon. It reviews literature demonstrating sex segregation in friendships and normative contexts from childhood through older adulthood. Possible mechanisms that may contribute to and result from lifelong sex segregation include behavioral compatibility, communication styles, resistance to cross-sex relationships, and institutional barriers. Future research is needed to better understand the topic across diverse populations and contexts.
Differences in finger length ratios between butch and femine
This journal article examines differences in finger length ratios between self-identified "butch" and "femme" lesbians. Prior research has found that auditory evoked potentials and otoacoustic emissions, markers of prenatal androgen exposure, are more masculine in lesbians compared to heterosexual women. This study explores whether the ratio of the length of the index finger to the ring finger (2D:4D), another purported marker of prenatal androgen exposure, differs between "butch" and "femme" lesbians.
Recommended
Integr. Comp. Biol.-2016-Burns-icb-icw017
This document summarizes a symposium presentation on the study of male reproductive morphology across different ecological conditions in five species of Japanese harvestmen. The researchers analyzed reproductive organs from populations that varied in elevation, latitude, and observed male-to-female sex ratios. They found that penis length decreased with increasing latitude, supporting the idea of physiological constraints in marginal habitats. Males from parthenogenetic species with female-biased populations had traits that may enhance precopulatory clasping ability compared to males from species with more even sex ratios. The findings suggest long-term sex ratio biases can influence the evolution of primary and secondary reproductive morphology.
Genetics aggression
1. Researchers study genetic factors related to aggressive behavior using twin and adoption studies to separate genetic and environmental influences. Twin studies compare rates of aggression in monozygotic (identical) twins who share all genes versus dizygotic (fraternal) twins who share about 50% of genes.
2. Meta-analyses of twin and adoption studies suggest genetics can account for around 50% of the variability in aggressive behavior, though the environment also plays a role.
3. While early research linked traits like the XYY genotype to increased aggression, later studies found no single genetic characteristic was associated with aggression, suggesting the initial genetic views of aggression were overemphasized.
Lucy donaldson
This document summarizes a study examining the relationship between linear enamel hypoplasias (LEHs) and adult stature in human skeletal remains from St. Gregory's Priory Cemetery in Canterbury, UK dating to the medieval period. The study found statistically significant relationships between LEHs and stature that differed between males and females. Females who experienced growth disruptions earlier in life tended to be taller, while males who experienced disruptions later were taller. The number of LEHs was also positively correlated with male stature. The results suggest early life stress can have a small impact on maximal adult height.
Variation and causes of variation
Assignment of Animal Breeding
By 16th Batch of Bsc.Ag 6th Semester
Roll No. 21-40
on Variation and Causes of Variation
Disseration Proposal
This document summarizes a proposed study that aims to examine the relationship between athletic participation and sexual aggression in college men. Specifically, it aims to determine if factors like masculinity, competitiveness, and sense of sexual entitlement can explain the reported association between athletics and sexual aggression. The study will survey male college wrestlers and non-athletes on measures of sexual experiences, masculinity, competitiveness, and sexual entitlement. It will analyze the relationships between these variables and test if the association between athletics and sexual aggression remains significant when accounting for masculinity-related factors. The findings could help inform intervention programs targeting populations at risk of sexual aggression.
Gosling
This document discusses a panel on animal personality research. It includes the chairs and presenters, which focus on using animal models like monkeys and fish to better understand the biological, genetic, and environmental bases of personality. The research aims to examine how personality may impact health, how personality can change over the lifespan, and help answer fundamental open questions about the nature and origins of personality.
Mehta & Strough_2009_ Sex segregation across the lifespan
This document summarizes research showing that sex segregation, or the separation of individuals into same-sex groups, persists across the lifespan rather than just being a childhood phenomenon. It reviews literature demonstrating sex segregation in friendships and normative contexts from childhood through older adulthood. Possible mechanisms that may contribute to and result from lifelong sex segregation include behavioral compatibility, communication styles, resistance to cross-sex relationships, and institutional barriers. Future research is needed to better understand the topic across diverse populations and contexts.
Differences in finger length ratios between butch and femine
This journal article examines differences in finger length ratios between self-identified "butch" and "femme" lesbians. Prior research has found that auditory evoked potentials and otoacoustic emissions, markers of prenatal androgen exposure, are more masculine in lesbians compared to heterosexual women. This study explores whether the ratio of the length of the index finger to the ring finger (2D:4D), another purported marker of prenatal androgen exposure, differs between "butch" and "femme" lesbians.
Homosexuality, birth order, and evolution
This article proposes that homosexuality can be explained by a polygenetic trait influenced by multiple genes. During development, these genes shift male brain development in a more feminine direction. While single alleles may produce homosexuality, carriers of these alleles who are heterosexual tend to be better fathers and more attractive mates. This balanced polymorphism allows alleles that contribute to homosexuality to survive by offsetting their negative reproductive impacts through positively impacting heterosexual carriers. A similar effect is proposed to exist for genes that could produce lesbianism in females.
Theories to Explain the Diversity of Life
This document contains the Theories to Explain the Diversity of Life. Two main theories of evolution i.e. Lamarckism and Darwinism are discussed.
Handedness, sexual orientation and gender
This journal article examines the relationship between handedness, sexual orientation, and gender-related personality traits. The introduction summarizes previous research finding associations between non-right handedness and homosexuality in both men and women, as well as gender identity disorder. Specifically, homosexual men were 34% more likely to be non-right handed than heterosexual men, and homosexual women were 91% more likely to be non-right handed than heterosexual women. The article also reviews evidence of slightly higher rates of left-handedness in males compared to females. Finally, a few studies found that non-right handed women tended to score higher on instrumentality and lower on expressiveness, exhibiting more male-typical personality traits.
Mettler_and_Spellman_2009
This study analyzed a hybrid zone between black-headed grosbeaks and rose-breasted grosbeaks in South Dakota. The researchers collected 143 birds across the hybrid zone and analyzed both morphological characteristics and genetic markers. They found low frequencies of hybrids, stability in the location and width of the hybrid zone over 40 years, and evidence that hybrids have reduced fitness. This supports a model where the hybrid zone is maintained as a "tension zone" due to a balance between dispersal into the zone and selection against hybrids.
Role Of Behavior In Evolution 1
Behavioral traits can change more quickly than morphology in response to environmental cues, allowing behaviors to lead evolutionary changes. A behavioral shift can occur faster than an adaptive change in physiology, taking the lead in evolution. While behaviors are flexible, they can also inhibit evolutionary changes by preventing natural selection from acting on other traits when environments change. A unified framework is needed to understand how behaviors can both drive and inhibit evolutionary processes through altering selection pressures.
Research project power point
The document summarizes a study that examined teenagers' views on masculine and feminine personality traits. Male participants were more likely than females to label traits as stereotypically masculine or feminine. However, both males and females labeled many traits as neutral, contrary to the hypothesis. This may indicate that younger generations are moving away from strict gender stereotypes. Repeating the study with a larger, more diverse sample could provide more insights into generational differences in views of masculinity and femininity.
Fisher theory
1. Fisher's Fundamental Theorem on Natural Selection states that the rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time.
2. The theorem has been revised and clarified over time, but generally means that natural selection will tend to increase the fitness of organisms through changes in gene frequencies.
3. Fisher framed his argument in terms of parental expenditure, suggesting that natural selection will act to equalize the total parental expenditure between male and female offspring to maximize reproductive value.
dissertation complete
This study investigated whether cooperation during predator inspection forms a behavioral syndrome with traits like exploration, boldness, activity, and sociability in guppies. The researcher predicted these behaviors would form a syndrome and that more cooperative individuals would be more explorative, bold, active, and affiliative. The results partially supported this, suggesting bolder individuals are more likely to cooperate during predator inspection. Possible explanations in terms of life history strategies and behavioral mechanisms are discussed, with considerations for ecological and evolutionary effects.
Weinstein08_Temperament_Affiliation
This study examined whether individual differences in infant temperament, as assessed in a biobehavioral assessment between 3-4 months of age, predicted the formation of affiliative relationships in 57 rhesus macaque yearlings. The researchers observed the yearlings over a 10-week period to record affiliative behaviors like proximity, play, contact and grooming. They found that yearlings who had scored high on "equability" as infants, indicating calmness and low activity, had fewer peer relationships. Yearlings also preferentially affiliated with peers who had similar scores on equability and adaptability from the infant assessment. Even after controlling for factors like kinship, rank and sex, infant temperament remained a significant predictor of variation
Biology form 5 chapter 6
Variation exists between individuals of the same species and can be continuous or discontinuous. It is caused by both genetic and environmental factors. Genetic variation results from genetic recombination during meiosis and cell division, as well as from mutations which are sudden changes in genes or chromosomes that can cause genetic disorders or death in humans. Environmental factors can also interact with genetic traits to produce variation important for a species' survival in a changing environment.
A neuropsychologic profile of gays
This article summarizes recent studies examining differences in neuropsychological profiles between homosexual and heterosexual men and women. Some studies have found differences in cognitive patterns between gay men and heterosexual men on tests that typically elicit sex differences, though two studies found no effects of sexual orientation. Little is known about differences between lesbians and heterosexual women, as the few published reports found no significant differences. The studies aim to understand the etiology of sexual orientation by examining neurocognitive development in the framework of psychosexual differentiation between the sexes.
Weinstein 2012 JCP
This study examined factors that predict the longitudinal stability of friendships in juvenile rhesus monkeys from age 1 to age 2. The researchers investigated whether individual characteristics (sex, dominance rank, family size, temperament assessed at 3-4 months) and relationship characteristics (kinship, reciprocity, complexity, similarity in sex, rank and temperament) predicted which friendships persisted over time. They found that males maintained more friendships than females from age 1 to 2. Relationships were more likely to be stable if individuals were similar in temperament, were kin, or the same sex. Reciprocated friendships were also more likely to persist than unidirectional relationships. The findings suggest factors influencing friendship maintenance in rhes
Sexual selection
This document discusses evolutionary theories around sexual selection and relationships. It explains that sexual selection occurs through intrasexual competition between males to attract females, and intersexual selection where females choose their mates. Research by Buss (1989) found cross-cultural differences in mate preferences, with females prioritizing resources and males prioritizing youth and attractiveness. Studies also show females' preferences change across their menstrual cycle and they favor more masculine traits when fertile. However, critics argue these theories are reductionist and deterministic by not accounting for free will or environmental influences on relationships.
Catastrophizing heritability
This study examined the heritability of pain catastrophizing using a twin study design. 400 twins completed measures of pain catastrophizing and underwent a cold pressor task experiment. Results showed pain catastrophizing was 37% heritable, with the remaining 63% due to unique environmental factors. The association between catastrophizing and increased pain response during the cold pressor task was not attributable to shared genetics or environment, suggesting a direct relationship between catastrophizing and experimental pain outcomes. This was the first study to examine the genetic contributions to catastrophizing and its relationship to experimental pain responses.
coldwater_spring
This document provides a summary of an ethnographic study of the former U.S. Bureau of Mines Twin Cities Research Center property in Hennepin County, Minnesota. The study identified Coldwater Spring on the property as culturally significant to Dakota and Ojibwe peoples. Interviews found that the spring is associated with Dakota creation beliefs and ceremonies requiring pure spring water. The study recommends Coldwater Spring as eligible for listing on the National Register of Historic Places as a traditional cultural property. It also reports that a Dakota tribe considers the spring to be a Sacred Site.
Towards a psychological profile for womb twin survivors
The progress of Althea Hayton's 10 year research programme to clarify the psychological profile of the womb twin survivor.
GD0756180
This presentation will be about the child refugees from the Greek Civil War of 1946-1949. Their story is not very well known, yet it is perhaps one of the saddest events in human history. This topic greatly interests me because it involves minorities that are persecuted in Greece.
Twins
This document discusses twins and their dependency on one another. It provides examples of twins Debbie and Dianne who felt comforted by the other's presence in new social situations like kindergarten and birthday parties. The twins note feeling a deep interdependency and relying on each other for support, with one twin being more social to help take pressure off the other. The document also explores reasons twins may differ from each other, such as environmental and epigenetic factors early in development.
Week 6 A2 Gottesman and Shields
The document discusses twin studies as a method used in psychology to understand the influence of genes and environment on behaviors and traits. Identical twins are useful to study because they share 100% of their genes. Comparing identical twins who were reared together or apart, as in adoption studies, allows researchers to determine if similarities in behaviors are due to genetic or environmental factors. The Gottesman and Shields study compared schizophrenia concordance rates in identical and fraternal twins to investigate the relative genetic and environmental influences on the disorder. The study found higher concordance in identical twins, supporting a genetic influence, but less than 100% concordance, also indicating an environmental role. Twin studies are a valuable method but have limitations such as potential bias in
Twins
This document discusses key statistics and information about twin pregnancies. Some key points include:
- Twin pregnancies account for 1% of all pregnancies and have increased risks of mortality and morbidity compared to singletons.
- Zygosity, chorionicity, and amnionicity determine the type and risks associated with different twin pregnancies.
- Monitoring for conditions like twin-twin transfusion syndrome is important in managing high-risk aspects of multiple gestations.
- Factors like discordant growth, vascular connections between twins, and single fetal demise can impact the health of twins.
Twin pregnancy....a journey.....
A 40-year-old primigravida with a BMI of 32 conceived twins through donor oocytes and is now in a twin pregnancy. Due to her advanced maternal age and twin gestation, her pregnancy requires careful monitoring to help ensure a safe journey. Key aspects of her care include screening for fetal abnormalities, monitoring fetal growth and well-being, and watching for potential complications associated with twin pregnancies such as twin-twin transfusion syndrome. Proper labeling and identification of the twins is also important.
Online Advertising
Online advertising provides many benefits for companies but also raises some ethical issues. Twin Info Solutions currently uses cost-per-click advertising and contextual ads to generate leads for their complex BPO services. The report recommends Twin try cost-per-lead models and video/forum ads showcasing customer feedback to better suit their needs. Behavioral targeting and email advertising could also help reach corporate decision makers. Overall online advertising is effective if used strategically while maintaining ethical standards.
More Related Content
What's hot
Homosexuality, birth order, and evolution
This article proposes that homosexuality can be explained by a polygenetic trait influenced by multiple genes. During development, these genes shift male brain development in a more feminine direction. While single alleles may produce homosexuality, carriers of these alleles who are heterosexual tend to be better fathers and more attractive mates. This balanced polymorphism allows alleles that contribute to homosexuality to survive by offsetting their negative reproductive impacts through positively impacting heterosexual carriers. A similar effect is proposed to exist for genes that could produce lesbianism in females.
Theories to Explain the Diversity of Life
This document contains the Theories to Explain the Diversity of Life. Two main theories of evolution i.e. Lamarckism and Darwinism are discussed.
Handedness, sexual orientation and gender
This journal article examines the relationship between handedness, sexual orientation, and gender-related personality traits. The introduction summarizes previous research finding associations between non-right handedness and homosexuality in both men and women, as well as gender identity disorder. Specifically, homosexual men were 34% more likely to be non-right handed than heterosexual men, and homosexual women were 91% more likely to be non-right handed than heterosexual women. The article also reviews evidence of slightly higher rates of left-handedness in males compared to females. Finally, a few studies found that non-right handed women tended to score higher on instrumentality and lower on expressiveness, exhibiting more male-typical personality traits.
Mettler_and_Spellman_2009
This study analyzed a hybrid zone between black-headed grosbeaks and rose-breasted grosbeaks in South Dakota. The researchers collected 143 birds across the hybrid zone and analyzed both morphological characteristics and genetic markers. They found low frequencies of hybrids, stability in the location and width of the hybrid zone over 40 years, and evidence that hybrids have reduced fitness. This supports a model where the hybrid zone is maintained as a "tension zone" due to a balance between dispersal into the zone and selection against hybrids.
Role Of Behavior In Evolution 1
Behavioral traits can change more quickly than morphology in response to environmental cues, allowing behaviors to lead evolutionary changes. A behavioral shift can occur faster than an adaptive change in physiology, taking the lead in evolution. While behaviors are flexible, they can also inhibit evolutionary changes by preventing natural selection from acting on other traits when environments change. A unified framework is needed to understand how behaviors can both drive and inhibit evolutionary processes through altering selection pressures.
Research project power point
The document summarizes a study that examined teenagers' views on masculine and feminine personality traits. Male participants were more likely than females to label traits as stereotypically masculine or feminine. However, both males and females labeled many traits as neutral, contrary to the hypothesis. This may indicate that younger generations are moving away from strict gender stereotypes. Repeating the study with a larger, more diverse sample could provide more insights into generational differences in views of masculinity and femininity.
Fisher theory
1. Fisher's Fundamental Theorem on Natural Selection states that the rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time.
2. The theorem has been revised and clarified over time, but generally means that natural selection will tend to increase the fitness of organisms through changes in gene frequencies.
3. Fisher framed his argument in terms of parental expenditure, suggesting that natural selection will act to equalize the total parental expenditure between male and female offspring to maximize reproductive value.
dissertation complete
This study investigated whether cooperation during predator inspection forms a behavioral syndrome with traits like exploration, boldness, activity, and sociability in guppies. The researcher predicted these behaviors would form a syndrome and that more cooperative individuals would be more explorative, bold, active, and affiliative. The results partially supported this, suggesting bolder individuals are more likely to cooperate during predator inspection. Possible explanations in terms of life history strategies and behavioral mechanisms are discussed, with considerations for ecological and evolutionary effects.
Weinstein08_Temperament_Affiliation
This study examined whether individual differences in infant temperament, as assessed in a biobehavioral assessment between 3-4 months of age, predicted the formation of affiliative relationships in 57 rhesus macaque yearlings. The researchers observed the yearlings over a 10-week period to record affiliative behaviors like proximity, play, contact and grooming. They found that yearlings who had scored high on "equability" as infants, indicating calmness and low activity, had fewer peer relationships. Yearlings also preferentially affiliated with peers who had similar scores on equability and adaptability from the infant assessment. Even after controlling for factors like kinship, rank and sex, infant temperament remained a significant predictor of variation
Biology form 5 chapter 6
Variation exists between individuals of the same species and can be continuous or discontinuous. It is caused by both genetic and environmental factors. Genetic variation results from genetic recombination during meiosis and cell division, as well as from mutations which are sudden changes in genes or chromosomes that can cause genetic disorders or death in humans. Environmental factors can also interact with genetic traits to produce variation important for a species' survival in a changing environment.
A neuropsychologic profile of gays
This article summarizes recent studies examining differences in neuropsychological profiles between homosexual and heterosexual men and women. Some studies have found differences in cognitive patterns between gay men and heterosexual men on tests that typically elicit sex differences, though two studies found no effects of sexual orientation. Little is known about differences between lesbians and heterosexual women, as the few published reports found no significant differences. The studies aim to understand the etiology of sexual orientation by examining neurocognitive development in the framework of psychosexual differentiation between the sexes.
Weinstein 2012 JCP
This study examined factors that predict the longitudinal stability of friendships in juvenile rhesus monkeys from age 1 to age 2. The researchers investigated whether individual characteristics (sex, dominance rank, family size, temperament assessed at 3-4 months) and relationship characteristics (kinship, reciprocity, complexity, similarity in sex, rank and temperament) predicted which friendships persisted over time. They found that males maintained more friendships than females from age 1 to 2. Relationships were more likely to be stable if individuals were similar in temperament, were kin, or the same sex. Reciprocated friendships were also more likely to persist than unidirectional relationships. The findings suggest factors influencing friendship maintenance in rhes
Sexual selection
This document discusses evolutionary theories around sexual selection and relationships. It explains that sexual selection occurs through intrasexual competition between males to attract females, and intersexual selection where females choose their mates. Research by Buss (1989) found cross-cultural differences in mate preferences, with females prioritizing resources and males prioritizing youth and attractiveness. Studies also show females' preferences change across their menstrual cycle and they favor more masculine traits when fertile. However, critics argue these theories are reductionist and deterministic by not accounting for free will or environmental influences on relationships.
What's hot (13)
Viewers also liked
Catastrophizing heritability
This study examined the heritability of pain catastrophizing using a twin study design. 400 twins completed measures of pain catastrophizing and underwent a cold pressor task experiment. Results showed pain catastrophizing was 37% heritable, with the remaining 63% due to unique environmental factors. The association between catastrophizing and increased pain response during the cold pressor task was not attributable to shared genetics or environment, suggesting a direct relationship between catastrophizing and experimental pain outcomes. This was the first study to examine the genetic contributions to catastrophizing and its relationship to experimental pain responses.
coldwater_spring
This document provides a summary of an ethnographic study of the former U.S. Bureau of Mines Twin Cities Research Center property in Hennepin County, Minnesota. The study identified Coldwater Spring on the property as culturally significant to Dakota and Ojibwe peoples. Interviews found that the spring is associated with Dakota creation beliefs and ceremonies requiring pure spring water. The study recommends Coldwater Spring as eligible for listing on the National Register of Historic Places as a traditional cultural property. It also reports that a Dakota tribe considers the spring to be a Sacred Site.
Towards a psychological profile for womb twin survivors
The progress of Althea Hayton's 10 year research programme to clarify the psychological profile of the womb twin survivor.
GD0756180
This presentation will be about the child refugees from the Greek Civil War of 1946-1949. Their story is not very well known, yet it is perhaps one of the saddest events in human history. This topic greatly interests me because it involves minorities that are persecuted in Greece.
Twins
This document discusses twins and their dependency on one another. It provides examples of twins Debbie and Dianne who felt comforted by the other's presence in new social situations like kindergarten and birthday parties. The twins note feeling a deep interdependency and relying on each other for support, with one twin being more social to help take pressure off the other. The document also explores reasons twins may differ from each other, such as environmental and epigenetic factors early in development.
Week 6 A2 Gottesman and Shields
The document discusses twin studies as a method used in psychology to understand the influence of genes and environment on behaviors and traits. Identical twins are useful to study because they share 100% of their genes. Comparing identical twins who were reared together or apart, as in adoption studies, allows researchers to determine if similarities in behaviors are due to genetic or environmental factors. The Gottesman and Shields study compared schizophrenia concordance rates in identical and fraternal twins to investigate the relative genetic and environmental influences on the disorder. The study found higher concordance in identical twins, supporting a genetic influence, but less than 100% concordance, also indicating an environmental role. Twin studies are a valuable method but have limitations such as potential bias in
Twins
This document discusses key statistics and information about twin pregnancies. Some key points include:
- Twin pregnancies account for 1% of all pregnancies and have increased risks of mortality and morbidity compared to singletons.
- Zygosity, chorionicity, and amnionicity determine the type and risks associated with different twin pregnancies.
- Monitoring for conditions like twin-twin transfusion syndrome is important in managing high-risk aspects of multiple gestations.
- Factors like discordant growth, vascular connections between twins, and single fetal demise can impact the health of twins.
Twin pregnancy....a journey.....
A 40-year-old primigravida with a BMI of 32 conceived twins through donor oocytes and is now in a twin pregnancy. Due to her advanced maternal age and twin gestation, her pregnancy requires careful monitoring to help ensure a safe journey. Key aspects of her care include screening for fetal abnormalities, monitoring fetal growth and well-being, and watching for potential complications associated with twin pregnancies such as twin-twin transfusion syndrome. Proper labeling and identification of the twins is also important.
Online Advertising
Online advertising provides many benefits for companies but also raises some ethical issues. Twin Info Solutions currently uses cost-per-click advertising and contextual ads to generate leads for their complex BPO services. The report recommends Twin try cost-per-lead models and video/forum ads showcasing customer feedback to better suit their needs. Behavioral targeting and email advertising could also help reach corporate decision makers. Overall online advertising is effective if used strategically while maintaining ethical standards.
Viewers also liked (9)
Towards a psychological profile for womb twin survivors
Towards a psychological profile for womb twin survivors
Similar to A twin registry study of male and female sexual orientation
Cognitive, behavioral and personality profiles
This study examined the cognitive, behavioral, and personality profiles of male monozygotic triplets who were discordant for sexual orientation. One brother was homosexual (HM) while the other two were heterosexual (HT1 and HT2). The triplets participated in a battery of tests measuring cognitive abilities, personality traits, speech characteristics, and physical traits. The study aimed to determine if HM's profile would differ from his heterosexual brothers, as predicted by theories that biological factors like prenatal hormones influence sexual orientation and related traits. Examining monozygotic triplets discordant for sexual orientation provided a unique opportunity to study potential biological influences while controlling for genetic factors.
Genetic and Environmental Influences on Female SexualOrienta
Genetic and Environmental Influences on Female Sexual
Orientation, Childhood Gender Typicality and Adult
Gender Identity
Andrea Burri1,2*, Lynn Cherkas2, Timothy Spector2, Qazi Rahman1*
1 Biological and Experimental Psychology Group, School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom, 2 Department
of Twin Research and Genetic Epidemiology, King’s College London, London, United Kingdom
Abstract
Background: Human sexual orientation is influenced by genetic and non-shared environmental factors as are two
important psychological correlates – childhood gender typicality (CGT) and adult gender identity (AGI). However,
researchers have been unable to resolve the genetic and non-genetic components that contribute to the covariation
between these traits, particularly in women.
Methodology/Principal Findings: Here we performed a multivariate genetic analysis in a large sample of British female
twins (N = 4,426) who completed a questionnaire assessing sexual attraction, CGT and AGI. Univariate genetic models
indicated modest genetic influences on sexual attraction (25%), AGI (11%) and CGT (31%). For the multivariate analyses, a
common pathway model best fitted the data.
Conclusions/Significance: This indicated that a single latent variable influenced by a genetic component and common non-
shared environmental component explained the association between the three traits but there was substantial
measurement error. These findings highlight common developmental factors affecting differences in sexual orientation.
Citation: Burri A, Cherkas L, Spector T, Rahman Q (2011) Genetic and Environmental Influences on Female Sexual Orientation, Childhood Gender Typicality and
Adult Gender Identity. PLoS ONE 6(7): e21982. doi:10.1371/journal.pone.0021982
Editor: Stacey Cherny, University of Hong Kong, Hong Kong
Received March 9, 2011; Accepted June 14, 2011; Published July 7, 2011
Copyright: � 2011 Burri et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: These authors have no support or funding to report.
Competing Interests: The authors have declared that no competing interests exist.
* E-mail: [email protected] (AB); [email protected] (QR)
Introduction
Understanding of the origins of sexual orientation can help
narrow competing developmental explanations for behavioral sex
differences in general and is of increasing importance to
researchers concerned with the physical and mental health of
sexual minorities [1,2]. Homosexuality appears to be a stable
sexual phenotype in humans with population-based surveys
suggesting lifetime prevalence of 2–4% in men and 0.5–1.5% in
women when measured as exclusive same-sex ‘‘feelings’’ (e.g.,
homosexual attractions and fantasies) [3,4]. The distribution of the
...
A neuropsychologic profile of homo and hetero
This article examines differences in neuropsychological profiles between homosexual and heterosexual men and women. It discusses previous research finding some cognitive differences between gay men and heterosexual men on measures of sex differences. The article presents the theory that prenatal sex hormones influence both sexual orientation and sexually dimorphic cognitive abilities by masculinizing or feminizing neural substrates in the brain during development. Studies of prenatal hormone manipulations in animals support this theory.
A neuropsychologic profile of homosexuasl and heterosexuals
This article examines differences in neuropsychological profiles between homosexual and heterosexual men and women. It discusses previous research finding some cognitive differences between gay men and heterosexual men on measures of sex differences. The article also reviews theories that sexual orientation develops from sex-atypical patterns of brain development influenced by prenatal sex hormones, with high androgen exposure during development masculinizing neural substrates related to sexual orientation and cognition.
Dermatoglyphics, handedness sex, and sexual orientation
This journal article examines the relationship between dermatoglyphics (fingerprint patterns), handedness, sex, and sexual orientation. It suggests that examining characteristics like dermatoglyphics and handedness, whose timing of formation is known, can help localize when sexual orientation is programmed during development. The article notes that fingerprint patterns are determined between 8-16 weeks of fetal life, while handedness appears to depend on prenatal genetic and environmental factors. It aims to replicate and expand on prior research examining theoretical associations between dermatoglyphic asymmetry, handedness, and sexual orientation.
Original ArticleAre there vocal cues to human developmenta.docx
Original Article
Are there vocal cues to human developmental stability? Relationships
between facial fluctuating asymmetry and voice attractiveness
Alexander K. Hill a,1, Rodrigo A. Cárdenas b, John R. Wheatley a, Lisa L.M. Welling a,2, Robert P. Burriss a,3,
Peter Claes c, Coren L. Apicella d, Michael A. McDaniel e, Anthony C. Little f, Mark D. Shriver a, David A. Puts a,g,⁎
a Department of Anthropology, The Pennsylvania State University, University Park, PA 16802, USA
b Department of Psychology, The Pennsylvania State University, University Park, PA 16802, USA
c KU Leuven, ESAT/PSI—UZ Leuven, MIRC—iMinds, Medical IT Department, Belgium
d Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA
e Department of Management, Virginia Commonwealth University, Richmond, VA 23284, USA
f Department of Psychology, University of Bath, Bath, UK
g Center for Brain, Behavior, and Cognition, The Pennsylvania State University, University Park, PA 16802, USA
a b s t r a c ta r t i c l e i n f o
Article history:
Initial receipt 26 November 2015
Final revision received 25 October 2016
Available online xxxx
Keywords:
3D images
Fluctuating asymmetry
Geometric morphometrics
Hunter-gatherers
Mate choice
Sexual selection
Fluctuating asymmetry (FA), deviation from perfect bilateral symmetry, is thought to reflect an organism's rela-
tive inability to maintain stable morphological development in the face of environmental and genetic stressors.
Previous research has documented negative relationships between FA and attractiveness judgments in humans,
but scant research has explored relationships between the human voice and this putative marker of genetic qual-
ity in either sex. Only one study (and in women only) has explored relationships between vocal attractiveness
and asymmetry of the face, a feature-rich trait space central in prior work on human genetic quality and mate
choice. We therefore examined this relationship in three studies comprising 231 men and 240 women from
two Western samples as well as Hadza hunter–gatherers of Tanzania. Voice recordings were collected and
rated for attractiveness, and FA was computed from two-dimensional facial images as well as, for a subset of
men, three-dimensional facial scans. Through meta-analysis of our results and those of prior studies, we found
a negative association between FA and vocal attractiveness that was highly robust and statistically significant
whether we included effect sizes from previously published work, or only those from the present research,
and regardless of the inclusion of any individual sample or method of assessing FA (e.g., facial or limb FA).
Weighted mean correlations between FA and vocal attractiveness across studies were −.23 for men and −.29
for women. This research thus offers strong support for the hypothesis that voices provide cues to genetic quality
in humans.
© 2016 Elsevier Inc. All rights reserved.
1. Introduction
Mate choice is predicated, in part, ...
Original ArticleAre there vocal cues to human developmenta.docx
Original Article
Are there vocal cues to human developmental stability? Relationships
between facial fluctuating asymmetry and voice attractiveness
Alexander K. Hill a,1, Rodrigo A. Cárdenas b, John R. Wheatley a, Lisa L.M. Welling a,2, Robert P. Burriss a,3,
Peter Claes c, Coren L. Apicella d, Michael A. McDaniel e, Anthony C. Little f, Mark D. Shriver a, David A. Puts a,g,⁎
a Department of Anthropology, The Pennsylvania State University, University Park, PA 16802, USA
b Department of Psychology, The Pennsylvania State University, University Park, PA 16802, USA
c KU Leuven, ESAT/PSI—UZ Leuven, MIRC—iMinds, Medical IT Department, Belgium
d Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA
e Department of Management, Virginia Commonwealth University, Richmond, VA 23284, USA
f Department of Psychology, University of Bath, Bath, UK
g Center for Brain, Behavior, and Cognition, The Pennsylvania State University, University Park, PA 16802, USA
a b s t r a c ta r t i c l e i n f o
Article history:
Initial receipt 26 November 2015
Final revision received 25 October 2016
Available online xxxx
Keywords:
3D images
Fluctuating asymmetry
Geometric morphometrics
Hunter-gatherers
Mate choice
Sexual selection
Fluctuating asymmetry (FA), deviation from perfect bilateral symmetry, is thought to reflect an organism's rela-
tive inability to maintain stable morphological development in the face of environmental and genetic stressors.
Previous research has documented negative relationships between FA and attractiveness judgments in humans,
but scant research has explored relationships between the human voice and this putative marker of genetic qual-
ity in either sex. Only one study (and in women only) has explored relationships between vocal attractiveness
and asymmetry of the face, a feature-rich trait space central in prior work on human genetic quality and mate
choice. We therefore examined this relationship in three studies comprising 231 men and 240 women from
two Western samples as well as Hadza hunter–gatherers of Tanzania. Voice recordings were collected and
rated for attractiveness, and FA was computed from two-dimensional facial images as well as, for a subset of
men, three-dimensional facial scans. Through meta-analysis of our results and those of prior studies, we found
a negative association between FA and vocal attractiveness that was highly robust and statistically significant
whether we included effect sizes from previously published work, or only those from the present research,
and regardless of the inclusion of any individual sample or method of assessing FA (e.g., facial or limb FA).
Weighted mean correlations between FA and vocal attractiveness across studies were −.23 for men and −.29
for women. This research thus offers strong support for the hypothesis that voices provide cues to genetic quality
in humans.
© 2016 Elsevier Inc. All rights reserved.
1. Introduction
Mate choice is predicated, in part,.
A neuropsychologic profile of homosexual and heterosexual
This article summarizes recent studies examining differences in neuropsychological profiles between homosexual and heterosexual men and women. Some studies have found differences in cognitive patterns between gay men and heterosexual men on measures of typical sex differences, but two studies found no effects of sexual orientation. Little is known about differences between lesbians and heterosexual women, as the few published reports found no significant differences. The studies aim to understand the etiology of sexual orientation by examining neurocognitive development in the direction of one's opposite sex. Prenatal hormone theory suggests high concentrations of androgenic hormones during brain development masculinize neural substrates related to sexual orientation and cognition.
Homosexuality, birth order, and evolution (2)
This journal article proposes that homosexuality can be explained by a polygenetic trait influenced by multiple genes. During development, these genes shift male brain development in a more feminine direction. While single alleles may produce homosexuality, carriers of these alleles who are heterosexual tend to be better fathers and more attractive mates. There is a balanced polymorphism where the feminizing effects in heterosexuals offsets the reproductive disadvantages of these alleles contributing to homosexuality. The birth order effect on homosexuality may be a byproduct of a mechanism that shifts later-born sons' personalities more femininely, reducing competition with brothers.
Rayner Tai - Empirical Report Complete
This document summarizes a research study that examined differences in the mate preferences of parents based on the gender of their child. The study used an eye tracker to measure how long parents gazed at different characteristics, like attractiveness and career prospects, in profiles of potential sons/daughters-in-law. Based on evolutionary theory, the study predicted that mothers of daughters would spend more time on career traits than other parents, and fathers of sons would spend more time on attractiveness. The results provided support for evolutionary explanations of mate preferences over social role theory.
Finger length ratios in female monozygotic twins
This study examines finger length ratios in female monozygotic twins who are discordant for sexual orientation. Previous research has found that lesbian women tend to have lower finger length ratios, suggesting higher prenatal androgen exposure. The study aims to determine if differences in prenatal environment contribute to differences in sexual orientation for these twins by examining their finger length ratios. If finger length ratios differ between twins discordant for sexual orientation, it would provide evidence that prenatal environment, not just genetics, impacts development of sexual orientation.
The incidence and frequency of marital sex in a national sampleP.docx
The incidence and frequency of marital sex in a national sample
PREVIOUS RESEARCH ON MARITAL INTERCOURSE FREQUENCY
A major source of information on marital sexual frequency is the landmark study by Kinsey and his colleagues (Kinsey, Pomeroy, & Martin, 1948; Kinsey, Pomeroy, Martin & Gebhard, 1953). With a diverse but nonprobability sample, they found that the median frequency of sexual intercourse per week was 2 to 2.5 times for married individuals under the age of 35. In a more recent national nonprobability study, Blumstein and Schwartz (1983) found that young couples had sex about two or three times per week: Forty-five percent of heterosexual couples married for 2 years or less had sex three times per week or more, and another 38% had sex between one and three times per week. For couples married 2 to 10 years, comparable percentages were 27% and 46%. Questions about the frequency of marital sexual intercourse were also included in large-scale studies of childbearing decisions and fertility, which were conducted with probability samples. These fertility studies (e.g., Trussell Westoff, 1980; Udry, 1980; Westoff, 1974), which surveyed only women, found rates of sexual frequency slightly lower than those reported in the nonprobability sexuality studies. For example, Westoff (1974) found that women under the age of 45 had sex an average of 1.7 times per week. The "sexual revolution" of the 1960s and 1970s did not result in much change in the frequency of marital sex. In the recent NORC survey, the average frequency of sex for sexually active, married respondents under age 60 was seven times a month, or 1.6 times a week (Lauman et al., 1994; Michael et al., 1994).
Although the exact average frequency for marital sex varies somewhat across types of studies, one consistent finding from previous research is that respondents who were older or married for a longer period of me reported a frequency lower than respondents who were younger or married for a shorter period of time (Blumstein & Schwartz, 1983; Edwards & Booth, 1976; Greeley, 1991; Hunt, 1974; James, 1983; Kinsey et al., 1948; Kinsey et al., 1953; Michael et al., 1994; Trussell & Westoff, 1980; Westoff, 1974). Longitudinal studies (e.g., James, 1981; Udry, 1980) and retrospective studies (e.g., Greenblat, 1983) have also documented a decline in sexual intercourse over even a few years of marriage.
Studies focusing specifically on older adults have found that marital sex continues beyond the age of 60, but at a lower frequency (for a review, see Riportella-Muller, 1989). The incidence and frequency of sex declines with each additional decade of life (Brecher, 1984). Greeley (1992) reported that the steepest decline in the incidence of marital sex occurs between the 5th and 6th decade of life. Sixty-one percent of people in their fifties reported having sex with their spouse at least once a week, compared with 37% of those in their sixties. These studies of older adults highlight the imp ...
c⃝ Indian Academy of SciencesRESEARCHARTICLESexual con.docx
1) The study used experimental evolution to investigate the interaction between intralocus sexual conflict, sexual dimorphism, and adaptation to environmental variation in Drosophila melanogaster populations selected for desiccation resistance over 46 generations.
2) The desiccation-selected populations showed increased survival time under arid conditions and body weight compared to control populations, but this adaptation came at a cost of reduced preadult viability and female fecundity.
3) The sexes showed differing patterns of desiccation resistance and resource acquisition in response to selection, with a trend toward increasingly female-biased sexual size dimorphism, suggesting divergent selection pressures on males and females from the same environmental stress.
Ans.) Researchers have found much more proof that sexual orientation.pdf
Ans.) Researchers have found much more proof that sexual orientation is to a great extent
controlled by hereditary qualities, not decision. That can undermine a noteworthy contention
against the LBGT people group that claims that these individuals are living \"unnaturally.\"
According to latest research conducted and published in scientific journals the two areas of
human genome - one on the X chromosome and one on chromosome 8.
The relationship amongst science and sexual orientation is a subject of deep research and
analysis. A straightforward and particular determinant for sexual orientation has not been
indisputably illustrated; different studies indicate diverse, notwithstanding clashing positions,
however researchers theorize that a blend of genetics, hormonal and social elements decide
sexual orientation. Biological hypotheses for clarifying the reasons for sexual orientation are
more popular and natural elements may include an intricate interaction of hereditary components
and the early uterine, environment. These variables, which might be identified with the
improvement of a hetero, gay person, promiscuous orientation, incorporate qualities, pre-birth
hormones, and cerebrum structure.
According to a study, every single grown-up twin in Sweden (more than 7,600 twins) found that
same-sex conduct was clarified by both genetic elements and individual-particular natural
sources, (for example, pre-birth environment, involvement with sickness and injury and also peer
bunches and sexual encounters), while impacts of shared-environment factors, for example,
familial environment and social demeanors had a weaker, yet noteworthy impact. Women
demonstrated a factually non-critical pattern to weaker impact of genetic impacts, while men
demonstrated no impact of shared ecological impacts.
Chromosome linkage analysis of sexual orientation has shown the presence of different
contributing hereditary elements all through the genome. In 1993 Dean Hamer and partners
published their finding from a linkage examination of a specimen of 76 homo siblings and their
families. The researcher found that the homo men had more homo male uncles and cousins on
the maternal side of the family than on the fatherly side. Gay siblings who demonstrated this
maternal family were then tried for X chromosome linkage, utilizing twenty-two markers on the
X chromosome to test for comparable alleles. In another discovering, thirty-three of the forty kin
sets tried were found to have comparable alleles in the distal district of Xq28, which was
altogether higher than the normal rates of half for friendly siblings. This was prominently named
the \" homo quality\" in the media, bringing on noteworthy discussion. Sanders et al. in 1998
investigated their comparative study, in which they found that 13% of uncles of homosexual
siblings on the maternal side were homo person, contrasted and 6% on the fatherly side.
Hence, it is concluded that up to some extent homosexuality or sex orient.
Lit Review Slideshow
This literature review examines research on parenting by gay and lesbian couples compared to heterosexual couples. Several studies found no significant differences in child development or well-being based on parental sexual orientation. Children of gay and lesbian parents were shown to be psychologically healthy and well-adjusted, with academic performance and relationships not impacted by family type. The research supports the hypothesis that gay and lesbian parents are just as effective as heterosexual parents.
Arch Sex Behav (2007) 36235–249DOI 10.1007s10508-006-9155-.docx
Arch Sex Behav (2007) 36:235–249
DOI 10.1007/s10508-006-9155-y
O R I G I N A L PA P E R
Gender and Sexual Orientation Differences in Cognition Across
Adulthood: Age Is Kinder to Women than to Men Regardless
of Sexual Orientation
Elizabeth A. Maylor · Stian Reimers · Jean Choi ·
Marcia L. Collaer · Michael Peters · Irwin Silverman
Published online: 10 March 2007
C© Springer Science+Business Media, LLC 2007
Abstract Despite some evidence of greater age-related de-
terioration of the brain in males than in females, gender
differences in rates of cognitive aging have proved inconsis-
tent. The present study employed web-based methodology
to collect data from people aged 20–65 years (109,612 men;
88,509 women). As expected, men outperformed women on
tests of mental rotation and line angle judgment, whereas
women outperformed men on tests of category fluency and
object location memory. Performance on all tests declined
with age but significantly more so for men than for women.
Heterosexuals of each gender generally outperformed bi-
sexuals and homosexuals on tests where that gender was
superior; however, there were no clear interactions between
E. A. Maylor (�)
Department of Psychology, University of Warwick,
Coventry CV4 7AL, UK
e-mail: [email protected]
S. Reimers
Department of Psychology, University College London,
London, UK
J. Choi
Department of Psychology, University of Lethbridge,
Lethbridge, Alberta, Canada
M. L. Collaer
Department of Psychology and Program in Neuroscience,
Middlebury College,
Middlebury, Vermont, USA
M. Peters
Department of Psychology, University of Guelph,
Guelph, Ontario, Canada
I. Silverman
Department of Psychology, York University,
North York, Ontario, Canada
age and sexual orientation for either gender. At least for
these particular tests from young adulthood to retirement,
age is kinder to women than to men, but treats heterosexuals,
bisexuals, and homosexuals just the same.
Keywords Gender . Sexual orientation . Cognition .
Aging . Internet
Introduction
Many aspects of cognitive function show age-related decline
from young adulthood to old age (for reviews, see Birren &
Schaie, 2001; Craik & Salthouse, 2000; Perfect & Maylor,
2000; Salthouse, 1991). An important focus of much re-
search in cognitive gerontology has been on the identification
of possible factors associated with slower rates of decline,
with some significant results (e.g., see Hawkins, Kramer,
& Capaldi, 1992, on aerobic exercise; Lövdén, Ghisletta, &
Lindenberger, 2005, on social participation) but also some
null effects (e.g., see Rabbitt, Chetwynd, & McInnes, 2003,
on intellectual ability and socioeconomic status; Salthouse,
Berish, & Miles, 2002, on cognitive stimulation). One factor
that has so far “received little attention” (Meinz & Salthouse,
1998) is that of gender. In this article, we present the largest-
scale study to date of the association between gender and
age-cognition relations from young adulthood to retirement
age. .
Review Paper Presentation
This review paper explores whether women who marry young are more likely to commit adultery compared to those who marry later. It analyzes factors like age at marriage, prevalence of marital problems, and personality characteristics. The author proposes using a quantitative approach and survey to determine the correlation between age at marriage and reported incidents of infidelity. Previous research found marital dissatisfaction, marrying young, and certain personality traits can predict infidelity and divorce. Religiosity may also impact attitudes towards infidelity. Further study is needed to better define infidelity and establish relationships between age, personality, and unfaithful behavior.
Running head IS A PERSON BORN GAY .docx
The document discusses whether being gay is something someone is born with or a behavior acquired through environmental influences. It reviews perspectives from both sides of the debate, citing scientific studies that have attempted to study biological factors like genetics, brain structures, and hormone levels, as well as psychosocial factors like childhood experiences and relationships. However, the document concludes that there is no clear evidence that definitively proves either the innate or learned nature of sexual orientation, as different studies have limitations and conflicting results. The issue remains controversial with arguments on both sides.
Presentation1
This document discusses heterosexual society's negative views of bisexuality. It identifies three primary reasons for discrimination against bisexuals: seeing them as promiscuous, feeling threatened by open sexuality, and assuming sexuality is dichotomous rather than a continuum. Negative attitudes were exacerbated by the AIDS epidemic in the 1980s and 90s. Men tend to be more biphobic than women as a way to affirm their masculinity by rejecting what is seen as unmanly. While some bisexual activity arises from desire, others engage in it due to comfort, necessity, or opportunity without intimacy. Overall, resentment toward bisexuals stems from cultural influences, beliefs, and ignorance of stereotypes.
Effects of Sexuality and Career Choice on Perceived Femininity of Fathers
This study examined how a man's career choice (stay-at-home caregiver or working) and sexuality (homosexual or heterosexual) affected perceptions of his femininity. 98 participants read one of four vignettes that varied these factors, and completed a survey measuring perceived femininity. Results found no significant effects - a man's perceived femininity did not differ based on his career, sexuality, or their interaction. This suggests a lack of stigma or bias related to caregiving or homosexual fathers. While the hypotheses were not supported, the findings imply that perceptions are becoming less guided by gender stereotypes.
Similar to A twin registry study of male and female sexual orientation (20)
Genetic and Environmental Influences on Female SexualOrienta
Genetic and Environmental Influences on Female SexualOrienta
A neuropsychologic profile of homosexuasl and heterosexuals
A neuropsychologic profile of homosexuasl and heterosexuals
Dermatoglyphics, handedness sex, and sexual orientation
Dermatoglyphics, handedness sex, and sexual orientation
Original ArticleAre there vocal cues to human developmenta.docx
Original ArticleAre there vocal cues to human developmenta.docx
Original ArticleAre there vocal cues to human developmenta.docx
Original ArticleAre there vocal cues to human developmenta.docx
A neuropsychologic profile of homosexual and heterosexual
A neuropsychologic profile of homosexual and heterosexual
The incidence and frequency of marital sex in a national sampleP.docx
The incidence and frequency of marital sex in a national sampleP.docx
c⃝ Indian Academy of SciencesRESEARCHARTICLESexual con.docx
c⃝ Indian Academy of SciencesRESEARCHARTICLESexual con.docx
Ans.) Researchers have found much more proof that sexual orientation.pdf
Ans.) Researchers have found much more proof that sexual orientation.pdf
Arch Sex Behav (2007) 36235–249DOI 10.1007s10508-006-9155-.docx
Arch Sex Behav (2007) 36235–249DOI 10.1007s10508-006-9155-.docx
Effects of Sexuality and Career Choice on Perceived Femininity of Fathers
Effects of Sexuality and Career Choice on Perceived Femininity of Fathers
More from Teresa Levy
Identidadebiologica da homosexualidade
Este documento discute a relação entre a identidade homossexual e a biologia. Afirma que muitos homossexuais acreditam que nasceram assim, ao contrário das feministas que rejeitaram a ideia de destino biológico. No entanto, a identidade biológica homossexual exerce uma dupla violência, sendo uma diferença psicológica e não biológica. O documento também descreve a história do conceito de identidade biológica homossexual desde o século XIX e como estudos cientí
Identidadebiologica da homo bio
1. O documento discute a relação entre homossexualidade e discursos biológicos, notando que enquanto os movimentos feministas rejeitaram explicações biológicas, os movimentos gay adotaram explicações de "nascer assim".
2. Isso levou a noções como "cérebro gay" e "gene gay" que são bem aceitos pelo público, apesar de usos anteriores desse tipo de explicação para fins racistas e sexistas.
3. Há debates sobre se a aceitação do "inatismo gay" se deve mais a sentiment
How hormones affect behavioral and neural development
This document provides an introduction to a special issue journal on how gonadal hormones affect behavioral and neural development. It summarizes several studies showing that hormones like testosterone and estrogen influence behaviors in humans and other species. For example, females exposed to high testosterone levels prenatally tend to show more male-typical behaviors. The introduction discusses themes across the special issue articles, such as how hormones have both organizational effects during development and activational effects in adulthood. It also provides background on the range of methods used to study hormone-behavior relationships.
Homosexuality and biology
The document discusses research into the biological basis of homosexuality from the perspective of psychiatry and neurobiology. Early research treated homosexuality as a mental illness for psychiatry to treat. Later, neurobiology framed it as a natural variation in behavior and studied anatomical differences between the brains of straight and gay men using standard experimental designs to identify significant differences. However, the research approaches did not question predefined categories of what is considered "natural" and often objectified the people studied.
Homosexuality and bio
The document summarizes the current scientific research into the biological factors that influence sexual orientation. It notes that biology has begun to study what causes homosexuality and has provided some early answers, though the findings are still tentative. It also acknowledges that researching sexuality and the brain is challenging given our limited understanding of neurobiology. Some fear the quest to find biological explanations could lead to hype or be an intellectual dead end. The document concludes by saying the topic is politically charged, which has led to professional rivalries among researchers, some of whom have personal motivations as they themselves are gay.
Hand preference, sexual preference and transsexualism
This journal article examines the relationship between hand preference, sexual preference, and transsexualism. The authors studied 443 male-to-female and 93 female-to-male transsexuals and found they were more often non-right handed compared to male and female controls. This suggests an altered pattern of cerebral hemispheric organization in transsexuals. Prenatal androgen levels may influence both handedness and psychosexual development. Elevated testosterone in utero could affect brain development and increase non-right handedness.
Genes and human behavior
This document summarizes a journal article about genes and human behavior. The article reviews research on the genetic influences of cognitive abilities, personality traits, health habits, and psychopathology. It discusses studies on conditions like reading disabilities, Fragile-X syndrome, alcoholism, schizophrenia, and Alzheimer's disease. The article also examines new molecular genetics approaches and debates around behavioral genetics research.
Gay science
This document provides an introduction to the book "Gay Science: The Ethics of Sexual Orientation Research" by Timothy F. Murphy. The introduction outlines the ongoing scientific and social debate around the origins and meaning of sexual orientations like homosexuality. It notes that while past research often assumed homosexuality was a psychological disorder, more recent research takes a neutral stance on causation but still has social implications. The introduction previews the book's aim to provide an ethical analysis of sexual orientation research and its potential impacts, both positive and negative, on gay people. It does not intend to argue for any particular causal theory but rather map out the relevant issues for discussion.
Female sexual orientation and pubertal onset
This article examines the relationship between female sexual orientation and pubertal onset. The researchers hypothesized that lesbians would have a later, more masculine age of pubertal onset compared to heterosexual women based on theories that both sexual orientation and pubertal timing are influenced by prenatal androgens. They studied samples of community volunteers and discordant twins but found no significant differences in pubertal onset between homosexual and heterosexual women, contrary to their hypothesis.
Evolutionary perspective of sex typed toy preferences
This article discusses an evolutionary perspective on sex-typed toy preferences in children. It proposes that evolved visual processing biases may contribute to differences in how boys and girls interact with toys. Selection pressures that evolved male preferences for male playmates and female roles related to object features and functions may influence children's toy choices in adaptive ways. Research on sex differences in spatial abilities, color vision, and the social and biological factors that shape toy preferences is reviewed to support this perspective.
Empowerment and medicalization of homosexuality
This article summarizes the origins of the Committee for the Study of Sex Variants, formed in 1935 to study homosexuality. It involved collaboration between the homosexual community, represented by activist Jan Gay, and the medical community, led by Dr. Robert Latou Dickinson. However, their interests conflicted, as physicians sought to medicalize and pathologize homosexuality rather than empower the community. The committee's study, while well-intentioned, undermined Gay's goals and served to further subjugate homosexuals under the medical gaze. The collaboration nonetheless anticipated later efforts to establish a more equitable relationship between researchers and their subjects.
Elizabeth anderson
Evolutionary psychology holds that human behaviors, like mate selection and aggression, evolved through natural selection to promote survival and reproduction. According to this view, humans look for symmetry, averageness, and signs of fertility like hormone levels in mates. Some evolutionary psychologists have proposed that rape tendencies could have evolved as a reproductive strategy for socially unsuccessful males to pass on their genes. However, others argue this does not justify such behavior today. Evolutionary psychology remains controversial as some view it as suggesting unequal chances for success.
Defining the brain systems of lust
This article discusses three brain systems related to human mating and reproduction: lust, romantic attraction, and attachment. Lust evolved to initiate mating with any appropriate partner for sexual gratification. Attraction evolved to help individuals choose and prefer specific mating partners to conserve time and energy. Attachment evolved to enable individuals to cooperate with a reproductive mate until parental duties are completed. The article defines these three systems and discusses an ongoing study using fMRI to investigate the neural circuits associated with romantic attraction.
Constitutional classifications and the gay gene
This document is a transcript from a speech given by a law professor. In the speech, the professor discusses their niece Rebecca who has faced many health complications due to congenital defects, including heart defects and an intestinal obstruction. The professor notes that Rebecca received treatment in Canada, which has a national healthcare system, and wonders what would have happened if she was born in the US without adequate insurance. The professor then discusses how Rebecca's condition has led them to think about issues relating to genetics, prenatal testing, and insurance coverage of experimental treatments. The main points of the speech are to share a personal story about their niece to emphasize the impact of genetic conditions, and to discuss the legal perspectives around these issues.
Bio rhetoric, background beliefs
This journal article summarizes and critiques arguments for biological bases of homosexuality. It notes that while recent media attention has focused on certain studies finding biological influences on homosexuality, scientific study of biological factors has a long history. However, the assumption that findings of biological influences will reduce discrimination is problematic. Specifically, the research often does not include lesbians or bisexuals and thus may only benefit gay men legally. Additionally, basing the argument for gay rights entirely on biological research places the movement in a precarious position if that research is contradicted or made obsolete over time.
Bio rhetoric, background beliefs and the biology of homosexuality
This journal article summarizes and critiques arguments for biological bases of homosexuality. It notes that while recent media attention has focused on certain studies finding biological influences on homosexuality, scientific study of biological factors has occurred for over a century. However, the assumption that biological findings will reduce discrimination is problematic. Specifically, the research often does not include lesbians or bisexuals and so may only benefit gay men legally. Additionally, basing civil rights arguments entirely on scientific findings leaves the arguments vulnerable if the research is contradicted later.
Bio rhetoric, background beliefs and the biology of homo
This journal article discusses a biological study from the 1990s that claimed to find a "gay gene" linked to male homosexuality. The article notes that while this research was hailed as supporting gay rights, it actually only benefited a specific group - male homosexuals. Additionally, relying too heavily on biological determinism to argue for gay rights places the movement in a precarious position, as later studies may contradict initial findings. The article argues the biological research on sexuality is more complex than advocates suggest and does not necessarily advance LGBT equality.
Bio rhetoric, background beliefs and the bio of homo
This journal article summarizes and critiques arguments for biological bases of homosexuality. It notes that while recent media attention has focused on certain studies finding biological influences on homosexuality, scientific study of biological factors has occurred for over a century. However, the assumption that findings of biological influences will reduce discrimination is problematic. Specifically, the research often does not include lesbians or bisexuals and so may only benefit gay men legally. Additionally, basing the argument for gay rights entirely on scientific research leaves the argument vulnerable if that research is contradicted or made obsolete.
Biology and gay identity
This article discusses the history of the biological argument for gay identity and its relationship to the modern gay rights movement. It covers:
1) How Karl Heinrich Ulrichs first proposed in the 1860s that homosexuality was an innate "third sex", laying the basis for subsequent biological research and arguments for gay civil rights.
2) How Magnus Hirschfeld and his early 20th century research institute promoted the idea that homosexuality had biological or hormonal causes, gaining some scientific support from early endocrinology experiments.
3) How the German Social Democratic Party initially supported Hirschfeld's biological arguments as a basis for tolerance, though their views on homosexuality were mixed and based more on women
More from Teresa Levy (20)
How hormones affect behavioral and neural development
How hormones affect behavioral and neural development
Hand preference, sexual preference and transsexualism
Hand preference, sexual preference and transsexualism
Evolutionary perspective of sex typed toy preferences
Evolutionary perspective of sex typed toy preferences
Bio rhetoric, background beliefs and the biology of homosexuality
Bio rhetoric, background beliefs and the biology of homosexuality
Bio rhetoric, background beliefs and the biology of homo
Bio rhetoric, background beliefs and the biology of homo
Bio rhetoric, background beliefs and the bio of homo
Bio rhetoric, background beliefs and the bio of homo
A twin registry study of male and female sexual orientation
- 1. • A Twin Registry Study of Male and Female Sexual Orientation • Journal article by Scott L. Hershberger; The Journal of Sex Research, Vol. 34, 1997 A twin registry study of male and female sexual orientation. by Scott L. Hershberger Biological approaches to the etiology of individual differences in human sexual orientation have received significant empirical support during the last few years. One impetus for this work has been the desire to explain the continual occurrence throughout time and place of homosexuality despite its apparent selective disadvantages (Ruse, 1988). The approaches have been diverse: Support has been obtained from neuroendocrine (LeVay, 1991), molecular genetic (Hamer, Hu, Magnuson, Hu, & Pattatucci, 1993), and behavioral genetic (Bailey & Pillard, 1991) perspectives. Arguably, behavioral genetic studies have provided the strongest evidence to date in affirming the role biology plays in influencing human sexual behavior (Bailey, 1995). Behavioral genetic studies rely on the relative similarity of family members of differing genetic resemblance to estimate the heritability and environmentality underlying a phenotype. Most commonly, behavioral genetic studies compare the similarity of monozygotic (MZ) and dizygotic (DZ) twins. My primary purpose for this article is to report the results of a twin study of sexual orientation to evaluate the influence of heredity in both men and women. Table 1 presents the pairwise concordances found for sexual orientation in MZ and same-sex DZ twins from seven of the largest twin studies. Although the magnitude of heritability suggested by the studies varies greatly, most suggest the presence of some genetic influence on sexual orientation. The only exception appears to be King and McDonald (1992). To date, the Bailey, Pillard, Neale, and Agyei (1993) study has been the only published, noncase study of female twin concordance for sexual orientation. Table 1 Probandwise Concordances From Twin Studies of Sexual Orientation Study MZ(a) % DZ(a) % Males: Kallmann, 1952(a),(b) 37/37 100 4/26 15 Heston & Shields, 1968(b) 2/4 50 1/7 14 Buhrich, Bailey, & Martin, 1991 8/17 47 0/3 0 Bailey & Pillard, 1991 29/56 52 12/54 22 King & McDonald, 1993 2/16 13 2/16 13 Whitam, Diamond, & Martin, 1993 22/34 65 4/14 29 Females: Bailey et al., 1993 34/71 48 6/37 16 Study Ascertainment Males: Kallmann, 1952(a),(b) Word of mouth Heston & Shields, 1968(b) Serial admission Buhrich, Bailey, & Martin, 1991 Twin registry Bailey & Pillard, 1991 Advertisement King & McDonald, 1993 Advertisement