This page contains links to articles on other sites and to academic and scientific papers.
The Google Document
Links to articles on History of transgender
Endres, Nikolai. Galli: Ancient Roman Priests. 2005. http://www.glbtqarchive.com/ssh/galli_S.pdf
Links to articles on Islam
Article on the difficulty of reforming Islam. https://www.academia.edu/25303917/Reforming_Islam_Challenges_and_Prospects
Why the Islamic World Turned Away from Science, by Hillel Ofek. Pub. The New Atlantis. http://www.thenewatlantis.com/publications/why-the-arabic-world-turned-away-from-science
Sex, Gender and Sexuality
Links to Full Books, download for free
Bailey, Dr J M. The Man Who Would Be Queen. http://faculty.wcas.northwestern.edu/JMichael-Bailey/TMWWBQ.pdf
Excellent primer explaining Blanchard’s Typology of Transsexualism. Review HERE.
Ellis, H. Havelock. Studies in the Psychology of Sex. Volumes 1-6 (Project Gutenberg, multiple file formats.)
Stryker, S., Whittle, S., (Eds) The Transgender Studies Reader https://forlackofsomegoodwriting.files.wordpress.com/2013/12/susan-stryker-and-stephen-whittle-eds-the-transgender-studies-reader.pdf
Collected essays. While biased towards a Humanities-based approach and lacking sufficient scientific input, still a useful read.
Raymond, J. The Transsexual Empire. https://autogynephiliatruth.files.wordpress.com/2015/04/the-transsexual-empire.pdf
Raymond’s provocative critique of transsexualism. This has been the foundation of much feminist criticism of transsexuals. Review to follow.
Links to Peer-reviewed papers.
Auer M K. Transgender Transitioning and Change of Self-Reported Sexual Orientation. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192544/
Bakker A The prevalence of transsexualism in The Netherlands. 1993. https://www.ncbi.nlm.nih.gov/pubmed/8488743
The prevalence of transsexualism in the Netherlands was estimated by counting all the subjects who were diagnosed as transsexuals by psychiatrists or psychologists and were subsequently hormonally treated and generally underwent sex-reassignment surgery. At the end of 1990, 713 Dutch-born transsexuals received treatment (507 men, 206 women). This amounts to a prevalence of 1:11,900 for male-to-female transsexualism and 1:30,400 for female-to-male transsexualism (population age 15 and above in both groups). The sex ratio was about 2.5 men to 1 woman. The most important reason for this relatively high prevalence seems to be the benevolent climate for the treatment of transsexualism in the Netherlands.
Bentler, P. A typology of transsexualism: Gender identity theory and data. https://www.researchgate.net/publication/22145678_A_typology_of_transsexualism_Gender_identity_theory_and_data
This paper pre-dates Blanchard and in it the authors describe three types of transsexual: homosexual, asexual and heterosexual. Blanchard was able to reconcile the two latter groups into one, autogynephilic.
Blanchard, R. Heterosexual and homosexual gender dysphoria https://rd.springer.com/article/10.1007/BF01542067
This study investigated why more males than females complain of dissatisfaction with their anatomical sex (gender dysphoria). New referrals to a university gender identity clinic were dichotomously classified as heterosexual or homosexual. There were 73 heterosexual and 52 homosexual males; 1 heterosexual and 71 homosexual females. The average heterosexual male was 8 years older at inception than the homosexual groups. The heterosexual males reported that their first cross-gender wishes occurred around the time they first cross-dressed, whereas the homosexual groups reported that cross-gender wishes preceded cross-dressing by 3–4 years. Some history of fetishistic arousal was acknowledged by over 80% of the heterosexual males, compared to fewer than 10% of homosexual males and no homosexual females. The results suggest that males are not differentially susceptible to gender dysphoria per se, but rather that they are differentially susceptible to one of the predisposing conditions, namely, fetishistic transvestism.
Blanchard, R, The Concept of Autogynephilia and the Typology of Male Gender Dysphoria. https://www.researchgate.net/publication/20361233_The_Concept_of_Autogynephilia_and_the_Typology_of_Male_Gender_Dysphoria
This is paper sets out the basis of Blanchard’s typology. The appendix contains his questionnaires. One of the most important sentences in it is this:
‘the central prediction of the present study, namely, that autogynephilic behavior will be reported more frequently by non-homosexual than by homosexual gender dysphorics.’ (My emphasis.)
It has been the consistent attempt of Western autogynephilic activists to attack Blanchard for making what they call ‘generalisations’. That is a straw man. Blanchard, in all his papers, is careful not to go beyond the science. This is demonstrated here. Unfortunately, too many people with a Humanities background, and who do not understand that science is about finding reasonable explanations for observed phenomena, think that their philosophical contentions are somehow worthwhile.
Blanchard, R. A History of Autogynephilia (pdf) Blanchard- History of Autogynephilia
Blanchard, R. Typology of male-to-female transsexualism http://link.springer.com/article/10.1007/BF01542107
Blanchard, R. The classification and labeling of nonhomosexual gender dysphorias http://link.springer.com/article/10.1007/BF01541951
Blanchard R, Collins PI., “Men with sexual interest in transvestites, transsexuals, and she-males”
Blanchard R., “The she-male phenomenon and the concept of partial autogynephilia”
Blanchard R,et al. Comparison of height and weight in homosexual versus nonhomosexual male gender dysphorics. http://link.springer.com/article/10.1007/BF01541833
Blanchard R, et al. Sexual Attraction to Others: A Comparison of Two Models of Alloerotic Responding in Men 2010 https://www.researchgate.net/publication/46289344_Sexual_Attraction_to_Others_A_Comparison_of_Two_Models_of_Alloerotic_Responding_in_Men
The penile response profiles of homosexual and heterosexual pedophiles, hebephiles, and teleiophiles to laboratory stimuli depicting male and female children and adults may be conceptualized as a series of overlapping stimulus generalization gradients. This study used such profile data to compare two models of alloerotic responding (sexual responding to other people) in men. The first model was based on the notion that men respond to a potential sexual object as a compound stimulus made up of an age component and a gender component. The second model was based on the notion that men respond to a potential sexual object as a gestalt, which they evaluate in terms of global similarity to other potential sexual objects. The analytic strategy was to compare the accuracy of these models in predicting a man’s penile response to each of his less arousing (nonpreferred) stimulus categories from his response to his most arousing (preferred) stimulus category. Both models based their predictions on the degree of dissimilarity between the preferred stimulus category and a given nonpreferred stimulus category, but each model used its own measure of dissimilarity. According to the first model (“summation model”), penile response should vary inversely as the sum of stimulus differences on separate dimensions of age and gender. According to the second model (“bipolar model”), penile response should vary inversely as the distance between stimulus categories on a single, bipolar dimension of morphological similarity-a dimension on which children are located near the middle, and adult men and women are located at opposite ends. The subjects were 2,278 male patients referred to a specialty clinic for phallometric assessment of their erotic preferences. Comparisons of goodness of fit to the observed data favored the unidimensional bipolar model.
Bockting et al. Gay and bisexual identity development among female-to-male transsexuals in North America: emergence of a transgender sexuality. https://www.ncbi.nlm.nih.gov/pubmed/19330439
Bogaert, Anthony F. The prevalence of male homosexuality: the effect of fraternal birth order and variations in family size 2004 http://www.sciencedirect.com/science/article/pii/S0022519304001584
Bullough, Vern L. Transgenderism and the Concept of Gender https://www.atria.nl/ezines/web/IJT/97-03/numbers/symposion/bullough.htm
Campbell, Natalie M. Nuclear family dynamics: Predictors of childhood crushes and adult sexual orientation 2015 http://mds.marshall.edu/cgi/viewcontent.cgi?article=1949&context=etd
Clemens, B. Male‐to‐female gender dysphoria: Gender‐specific differences in resting‐state networks 2017 (full) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5434195/
Recent research found gender‐related differences in resting‐state functional connectivity (rs‐FC) measured by functional magnetic resonance imaging (fMRI). To the best of our knowledge, there are no studies examining the differences in rs‐FC between men, women, and individuals who report a discrepancy between their anatomical sex and their gender identity, i.e. gender dysphoria (GD).
Our results provide first evidence that MtFs exhibit patterns of rs‐FC which are different from both their assigned and their aspired gender, indicating an intermediate position between the two sexes. We suggest that the present study constitutes a starting point for future research designed to clarify whether the brains of individuals with GD are more similar to their assigned or their aspired gender.
Del Giudice, M. Joel et al.’s method systematically fails to detect large, consistent sex differences (in human brains.) 2016. (Letter) http://www.pnas.org/content/113/14/E1965.full.pdf
Dreger, Alice D. The Controversy Surrounding The Man Who Would Be Queen: A Case History of the Politics of Science, Identity, and Sex in the Internet Age 2008 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3170124/
Freund, K.Cross-Gender Identity in a Broader Context https://link.springer.com/chapter/10.1007/978-1-4684-4784-2_9
This chapter is a review of clinical and experimental studies that may suggest questions useful in research on the etiology of cross-gender identity (which is here conceived as an extreme form of masculine gender identity in females or feminine gender identity in males). The first section addresses itself to the typology of cross-gender identity and demonstrates that there are two main types, one occurring in homosexual, the other in heterosexual (or just nonhomosexual) persons. Next, the relationships among androphilia (an erotic preference for physically mature males), homosexual-type cross-gender identity, and feminine gender identity (in males) in general are explored. The second section investigates the feasibility of physiological hypotheses of homosexual cross-gender identity and discusses, in this context, relevant work on the development of gender identity in intersexes. The third section explores the relevance of animal studies to the problem of gender identity.
Freund K et al. Two types of cross-gender identity. 1982 https://www.ncbi.nlm.nih.gov/pubmed/7073469/
A revision of the typology of male cross-gender identity was carried out by means of formalized, easily replicable methods. The results suggest (1) that there are two discrete types of cross-gender identity, one heterosexual, the other homosexual; (2) that transvestism, and closely related conditions of cross-gender identity, occur exclusively or almost exclusively in heterosexuals; (3) that of the two types of transsexualism distinguished in this study, type A is, in heterosexuals, very rare or completely nonexistent; (4) that (in the course of time) transvestites or borderline transsexuals (defined below) may develop sustained cross-gender identity, as observed by Stoller (1971); (5) that although, according to Hoenig and Kenna (1974), transsexualism by itself is not an anomalous erotic preference, it is (virtually) always either preceded by transvestism or accompanied by homosexuality or cross-gender fetishism.
Galis, Frietson. Sexual Dimorphism in the Prenatal Digit Ratio (2D:4D) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811245/
Green et al. Specific cross-gender behaviour in boyhood and later homosexual orientation. http://www.ncbi.nlm.nih.gov/pubmed/3676630
Guillamon, A, et al. A Review of the Status of Brain Structure Research in Transsexualism http://link.springer.com/article/10.1007/s10508-016-0768-5
Gurven, M and Hill, K. Why Do Men Hunt? A Reevaluation of “Man the Hunter” and the Sexual Division of Labor http://www.anth.ucsb.edu/faculty/gurven/papers/gurvenhill2009.pdf
Hahn, A.et al Structural Connectivity Networks of Transgender People 2015 https://www.ncbi.nlm.nih.gov/pmc/article/PMC4585501/ Full paper
Hare et al. Androgen receptor repeat length polymorphism associated with male-to-female transsexualism.http://www.ncbi.nlm.nih.gov/pubmed/18962445
There is a likely genetic component to transsexualism, and genes involved in sex steroidogenesis are good candidates. We explored the specific hypothesis that male-to-female transsexualism is associated with gene variants responsible for undermasculinization and/or feminization. Specifically, we assessed the role of disease-associated repeat length polymorphisms in the androgen receptor (AR), estrogen receptor β (ERβ), and aromatase (CYP19) genes.
A significant association was identified between transsexualism and the AR allele, with transsexuals having longer AR repeat lengths than non-transsexual male control subjects (p = .04). No associations for transsexualism were evident in repeat lengths for CYP19 or ERβ genes. Individuals were then classified as short or long for each gene polymorphism on the basis of control median polymorphism lengths in order to further elucidate possible combined effects. No interaction associations between the three genes and transsexualism were identified.
Hilleke E Hulshoff Pol, Changing your sex changes your brain: influences of testosterone and estrogen on adult human brain structure 2006 http://www.eje-online.org/content/155/suppl_1/S107.abstract
Objective: Sex hormones are not only involved in the formation of reproductive organs, but also induce sexually-dimorphic brain development and organization. Cross-sex hormone administration to transsexuals provides a unique possibility to study the effects of sex steroids on brain morphology in young adulthood.
Methods: Magnetic resonance brain images were made prior to, and during, cross-sex hormone treatment to study the influence of anti-androgen + estrogen treatment on brain morphology in eight young adult male-to-female transsexual human subjects and of androgen treatment in six female-to-male transsexuals.
Results: Compared with controls, anti-androgen + estrogen treatment decreased brain volumes of male-to-female subjects towards female proportions, while androgen treatment in female-to-male subjects increased total brain and hypothalamus volumes towards male proportions.
Conclusions: The findings suggest that, throughout life, gonadal hormones remain essential for maintaining aspects of sex-specific differences in the human brain.
Hsu, Rosenthal, Miller and Bailey, “Who are gynandromorphophilic men? Characterizing men with sexual interest in transgender women”
Karwowsk, Maciej Greater male variability in creativity: A latent variables approach 2016 http://www.sciencedirect.com/science/article/pii/S1871187116301407?via%3Dihub
Lagos et al. Regional Grey Matter Structure Differences between Transsexuals and Healthy Controls—A Voxel Based Morphometry Study. 2013. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0083947
Lawrence, A. Autogynephilia: A Paraphilic Model of Gender Identity Disorder.http://www.annelawrence.com/autogynephilia,_a_paraphilic_model_of_GID.pdf
Lawrence, Anne A. Autogynephilia and Heterosexuality 2012 https://link.springer.com/chapter/10.1007/978-1-4614-5182-2_7
Lawrence, A. Further Validation of Blanchard’s Typology: A Reply to Nuttbrock, Bockting, Rosenblum, Mason, and Hwahng (2010) https://www.researchgate.net/publication/50196878_Further_Validation_of_Blanchard’s_Typology_A_Reply_to_Nuttbrock_Bockting_Rosenblum_Mason_and_Hwahng_2010
Lawrence, Anne A. Clinical and Theoretical Parallels Between Desire for Limb Amputation and Gender Identity Disorder 2006 http://www.annelawrence.com/amputation-GID.pdf
Lawrence Anne A. Erotic Target Location Errors: An Underappreciated Paraphilic Dimension http://www.jstor.org/stable/pdf/20620414.pdf?seq=1#page_scan_tab_contents
Based on studies of heterosexual male fetishists, transvestites, and transsexuals, Blanchard (1991) proposed the existence of a hitherto unrecognized paraphilic dimension, erotic target location errors (ETLEs), involving the erroneous location of erotic targets in the environment. ETLEs can involve preferential attention to a peripheral or inessential part of an erotic target, manifesting as fetishism, or mislocation of an erotic target in one’s own body, manifesting as the desire to impersonate or become a facsimile of the erotic target (e.g., transvestism or transsexualism). Despite its potential clinical and heuristic value, the concept that ETLEs define a paraphilic dimension is underappreciated. This review summarizes the studies leading to the concept of ETLEs and describes how ETLEs are believed to manifest in men whose preferred erotic targets are women, children, men, amputees, plush animals, and real animals. This review also describes ETLEs in women; discusses possible etiologies of ETLEs; considers the implications of the ETLE concept for psychoanalytic theories of transvestism and male-to-female transsexualism, as well as for the forthcoming revision of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition; suggests reasons why the concept of ETLEs has been underappreciated; and describes what might result if the concept were more widely appreciated.
Lawrence, Dr Anne A. Erotic Target Location Errors are Easy to Mischaracterize: A Reply to Moser. 2009 http://www.tandfonline.com/doi/abs/10.1080/00224490903230061
Li et al. Childhood Gender-Typed Behavior and Adolescent Sexual Orientation: A Longitudinal Population-Based Study. 2016. https://www.repository.cam.ac.uk/bitstream/handle/1810/262671/Li_et_al-2017-Developmental_Psychology-AM.pdf
Little A C. Women’s preferences for masculinity in male faces are highest during reproductive age range and lower around puberty and post-menopause 2010 http://www.sciencedirect.com/science/article/pii/S0306453009003680
Lonsdor, Elizabeth V. Sex differences in nonhuman primate behavioral development http://onlinelibrary.wiley.com/doi/10.1002/jnr.23862/full
Sex differences in behavior and developmental trajectories in human children are of great interest to researchers in a variety of fields, and a persistent topic of discussion and debate is the relative contribution of biological vs. social influences to such differences. Given the potentially large effects of cultural and social influences on human child development, nonhuman primates are important model species for investigating the biological and evolutionary roots of sex differences in human development. This Mini-Review briefly summarizes the existing literature on sex-biased behavior toward infant nonhuman primates by mothers and other social partners, followed by a review of findings on sex differences (or lack thereof) in primate behavioral development from a variety of species in wild and naturalistic settings. These include differences in physical and social development, including play, grooming, and object manipulation patterns, as well as nursing and the development of foraging behavior.
Madison, Söderlund. Objectivity and realms of explanation in academic journal articles concerning sex/gender: a comparison of Gender studies and the other social sciences https://link.springer.com/content/pdf/10.1007%2Fs11192-017-2407-x.pdf (full text pdf)
Moser, C. Blanchard’s Autogynephilia Theory: A Critique http://www.tandfonline.com/doi/pdf/10.1080/00918369.2010.486241
Nuttbrock et al. A Further Assessment of Blanchard’s Typology of Homosexual Versus Non-Homosexual or Autogynephilic Gender Dysphoria. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2894986/
Paul, JP. Childhood cross-gender behavior and adult homosexuality: the resurgence of biological models of sexuality. http://www.ncbi.nlm.nih.gov/pubmed/8505540
Rieger et al. Sexual Arousal and Masculinity-Femininity of Women http://www.researchgate.net/publication/283260585_Sexual_Arousal_and_Masculinity-Femininity_of_Women
Roberts et al. The deep human prehistory of global tropical forests and its relevance for modern conservation 2017 https://www.nature.com/articles/nplants201793
Significant human impacts on tropical forests have been considered the preserve of recent societies, linked to large-scale deforestation, extensive and intensive agriculture, resource mining, livestock grazing and urban settlement. Cumulative archaeological evidence now demonstrates, however, that Homo sapiens has actively manipulated tropical forest ecologies for at least 45,000 years. It is clear that these millennia of impacts need to be taken into account when studying and conserving tropical forest ecosystems today. Nevertheless, archaeology has so far provided only limited practical insight into contemporary human–tropical forest interactions. Here, we review significant archaeological evidence for the impacts of past hunter-gatherers, agriculturalists and urban settlements on global tropical forests. We compare the challenges faced, as well as the solutions adopted, by these groups with those confronting present-day societies, which also rely on tropical forests for a variety of ecosystem services. We emphasize archaeology’s importance not only in promoting natural and cultural heritage in tropical forests, but also in taking an active role to inform modern conservation and policy-making.
Ruigrok, A et al. A meta-analysis of sex differences in human brain structure. 2014 http://www.sciencedirect.com/science/article/pii/S0149763413003011
Sexton, L et al Where the Margins Meet: A Demographic Assessment of Transgender Inmates in Male Prisons http://ucicorrections.seweb.uci.edu/files/2013/06/A-Demographic-Assessment-of-Transgender-Inmates-in-Mens-Prisons.pdf
Smenenyna, S et al. The Relationship between Adult Occupational Preferences and Childhood Gender Nonconformity among Samoan Women, Men, and Fa’afafine. https://www.researchgate.net/publication/301551770_The_Relationship_between_Adult_Occupational_Preferences_and_Childhood_Gender_Nonconformity_among_Samoan_Women_Men_and_Fa’afafine
Todd, B K et al. ‘Preferences for ‘Gender-typed’ Toys in Boys and Girls Aged 9 to 32 Months.’ 2016 http://onlinelibrary.wiley.com/doi/10.1002/icd.1986/abstract
Veale, Clarke and Lomax, “Sexuality of Male-to-Female Transsexuals”
Watkins Christopher D. Creating beauty: creativity compensates for low physical attractiveness when individuals assess the attractiveness of social and romantic partners 2017. http://rsos.royalsocietypublishing.org/content/4/4/160955
Weinberg MS et al. Men sexually interested in transwomen (MSTW): gendered embodiment and the construction of sexual desire.2010 https://www.ncbi.nlm.nih.gov/pubmed/19544216
Winter S, Udomsak N (2002) Male, Female and Transgender : Stereotypes and Self in Thailand. http://www.transgenderasia.org/paper_male_female.htm
Winter S. Gender Stereotype and Self among Transgenders: Underlying Elements. http://www.transgenderasia.org/paper_gender_stereotype.htm
Winter S. Language and Identity in Transgender. http://www.transgenderasia.org/paper-languageandidentity.pdf
Winter S and King M. Well and Truly Fucked: Transwomen, Stigma, Sex Work and Sexual Health. http://www.transgenderasia.org/paper-wellandtruly.pdf
Winter, S. Transpeople (Khom Kham Phet) in Thailand. http://www.transgenderasia.org/paper-khonkhamphet.pdf
Wu-jing, He Gender differences in creative thinking revisited: Findings from analysis of variability http://www.sciencedirect.com/science/article/pii/S0191886911003035
Zucker, K. et al. Physical attractiveness of boys with gender identity disorder http://link.springer.com/article/10.1007/BF01552910
Zucker, K J, et al. Sex-typed Behavior in Cross-Gender-Identified Children: Stability and Change at a One-Year Follow-up 1986 http://www.sciencedirect.com/science/article/pii/S0002713810601148
Children referred because of concerns about their gender identity development were compared to their siblings on 4 sex-typed measures (15 variables) at both assessment and a 1-year follow-up. At assessment, the gender-referred children different from their siblings on all but one variable. At follow-up, the gender-referred children either maintained or significantly reduced their degree of cross-gender behavior; compared to their siblings, however, they continued to differ on the majority of measures. Degree of behavioral change at follow-up correlated positively with number of therapy sessions (child, parent, and total) and the child therapist’s emphasis on gender identity issues.
Links to Non Peer-reviewed articles by reliable authors
Costello, CG. On Trans Gender Identity and the “Intersex Brain” http://trans-fusion.blogspot.fr/2012/08/on-trans-gender-identity-and-intersex.html
A man of intersex history takes a look at some of the more controversial strategies of trans activists.
Links to Theses and Dissertations.
Akhter, S. Visual Attention to Erotic Stimuli in Androphilic Male-to-Female Transsexuals. (PhD Thesis, approved.) http://digitalscholarship.unlv.edu/cgi/viewcontent.cgi?article=2402&context=thesesdissertations
Interesting to note the similarities here in responses, between ‘androphilic’ (homosexual or HSTS) transsexuals and heterosexual men, albeit to the opposite sex. Probably because MtF transsexuals are not women; they are men, inverted.
Links to Non-linked references (buy the book!)
Hirschfeld M. Die Transvestiten. Berlin, Germany: Alfred Pulver Macher; 1910
Links hosted on other sites:
The following links can be accessed through the University of Calgary’s web site:
Contents of the UCC archive: University-of-Calgary
Borderline Personality Disorder
Ryden G et al. Borderline Personality Disorder and Autism Spectrum Disorder in Females — A Cross-Sectional Study. 2008. Clinical Neuropsychiatry. http://www.clinicalneuropsychiatry.org/pdf/04_ryden_hetta.pdf
Sprague et al. Borderline Personality Disorder as a Female Phenotypic Expression of Psychopathy? 2012https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3323706/
Skodol, Bender. Why Are Women Diagnosed Borderline More Than Men? 2003https://link.springer.com/article/10.1023/A:1026087410516
Sansone and Sansone. Gender Patterns in Borderline Personality Disorder 2011 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3115767/
Sex and Gender
Alexander, Hines. Sex differences in response to children’s toys in nonhuman primates. 2002. http://www.ehbonline.org/article/S1090-5138(02)00107-1/pdf
Herzog Harold A. Gender Differences in Human–Animal Interactions: A Review 2007 http://paws.wcu.edu/herzog/Gender.pdf Full pdf
Baileya, et al. Finger length ratio (2D:4D )correlates with physical aggression in men but not in women http://web.missouri.edu/~segerti/2210/BaileyHurdfingerlength.pdf
Boesch C Sex differences in the use of natural hammers by wild chimpanzees: A preliminary report 1981 http://www.sciencedirect.com/science/article/pii/S0047248481800498
The chimpanzees of the Tai National Park, Ivory Coast, use clubs and stones to open different species of nuts. An intriguing sex difference has been observed in this behavior. It is almost exclusively females that open Coula nuts directly in the tree and crack the very hard Panda nuts. Both techniques are difficult and imply either anticipating the need of a hammer and its transport, or exact positioning of the nut and precise dosage of the hits. The efficiency of females is superior to that of males in the technique of cracking Coula nuts on the ground, which is performed by both sexes. Possible implications for the evolution of tool-use in humans are discussed.
Guadalupe et alia. Human subcortical brain asymmetries in 15,847 people worldwide reveal effects of age and sex. 2016https://link.springer.com/article/10.1007%2Fs11682-016-9629-z
The two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here we present the largest ever analysis of subcortical brain asymmetries, in a harmonized multi-site study using meta-analysis methods. Volumetric asymmetry of seven subcortical structures was assessed in 15,847 MRI scans from 52 datasets worldwide. There were sex differences in the asymmetry of the globus pallidus and putamen. Heritability estimates, derived from 1170 subjects belonging to 71 extended pedigrees, revealed that additive genetic factors influenced the asymmetry of these two structures and that of the hippocampus and thalamus. Handedness had no detectable effect on subcortical asymmetries, even in this unprecedented sample size, but the asymmetry of the putamen varied with age. Genetic drivers of asymmetry in the hippocampus, thalamus and basal ganglia may affect variability in human cognition, including susceptibility to psychiatric disorders.
Hines.M et al. Early androgen exposure and human gender development 2015 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4350266/
Moore R W et al. Abnormalities of sexual development in male rats with in utero and lactational exposure to the antiandrogenic plasticizer Di(2-ethylhexyl) phthalate. 2001 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1240240/ Full PDF
PHOENIX CH et al Organizing action of prenatally administered testosterone propionate on the tissues mediating mating behavior in the female guinea pig. 1959 https://www.ncbi.nlm.nih.gov/pubmed/14432658
Ritchie, S et al. Sex differences in the adult human brain: Evidence from 5,216 UK Biobank participants 2017 http://biorxiv.org/content/biorxiv/early/2017/04/04/123729.full.pdf
Ruigrok, Amber N.V. A meta-analysis of sex differences in human brain structure 2013 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969295/
de Vries, Geert J. 1Sex Differences in the Brain: the Relation between Structure and Function 2009 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3932614/
de Waal Frans B.M. Sex differences in the formation of coalitions among chimpanzees 1984 http://www.sciencedirect.com/science/article/pii/0162309584900049
Observations were made of spontaneous coalition formation during aggressive encounters among chimpanzees in a large, semicaptive colony. The analysis of several thousand instances, collected over a period of 5 years, revealed striking differences between adult males and females. Male coalitions changed over time and showed little connection with social bonds, as measured by associative behaviors. Females, in contrast, showed stable coalitions, which strongly overlapped with their social bonds. Also, coalition formation with males and females differed. Females were treated on the basis of their coalitions and bonds with others in the group; males were not.
A single difference in proximate social goals is proposed as an explanation for these and other differences. Male coalitions seem to serve status competition. Males may form flexible coalitions in order to rise in rank, and may adopt the role of group protector in order to maintain a high rank. Female coalitions seem to serve the protection of particular individuals, namely, friends and kin. A similar sex difference has been reported for human coalition formation in experimental game situations.
Wallen K. The Organizational Hypothesis: Reflections on the 50th anniversary of the publication of Phoenix, Goy, Gerall, and Young (1959). https://www.ncbi.nlm.nih.gov/pubmed/19446072
Whiten, Andrew et al. Conformity to cultural norms of tool use in chimpanzees 2005 https://search.proquest.com/central/docview/204572350 full pdf
Wolf CJ et al. Effects of prenatal testosterone propionate on the sexual development of male and female rats: a dose-response study. 2002 https://www.ncbi.nlm.nih.gov/pubmed/11752687
Testosterone plays a major role in male sexual development. Exposure of females to testosterone in utero can induce masculine characteristics such as anovulation, increased anogenital distance (AGD), absence of nipples, retention of male-like tissues, and agenesis of the lower vagina. In addition, high levels of androgens during fetal development can lead to toxic effects such as reduced litter size and viability. The study of the effects of testosterone administration during sexual differentiation provides a foundation for understanding the effects of environmental androgens on fetuses, a sensitive subpopulation. In the current study, we investigated the ability of a range of concentrations of testosterone propionate (TP) administered prenatally to masculinize female and alter male offspring, and measured maternal and fetal T levels. Pregnant Sprague-Dawley rats were dosed by sc injection on gestational day (GD) 14-19 (GD 1= day of plug) with either corn oil (vehicle; 0.1 ml/rat) or with 0.1 ml of TP solution at 0.1, 0.5, 1, 2, 5, or 10 mg/0.1 ml. Parturition was delayed at 2, 5, and 10 mg TP, litter size was reduced at 5 and 10 mg TP, and pup weight was significantly reduced in both sexes at 0.5 mg TP and higher doses. Viability of offspring was unaffected at any dosage level. Androgenic effects seen at 0.5 mg TP in females included increased AGD at weaning and adulthood, reduced number of areolas and nipples, cleft phallus, small vaginal orifice, and presence of prostate tissue. This dose of TP elevated maternal T levels 10x but had no effect on fetal T levels. At 1 mg TP and above, female AGD on postnatal day (PND) 2 (or postcoital day 24 [gestation length = 22(1/2)]) was increased; areolas and nipples were virtually eliminated; levator ani muscle, bulbourethral glands, and seminal vesicles (2 mg TP and above) were present; none of the females developed a vaginal orifice and many females in the 1 and 2 mg TP dose groups developed a greatly distended, fluid-filled uterus after puberty. Maternal T levels at 1 mg TP were elevated 30x, and female fetal T levels showed an 80% increase. Male offspring displayed a reduced AGD and body weight on PND 2 at 0.5 mg TP and higher doses. These effects were not evident by weaning and male offspring displayed no malformations. We conclude that gestational administration of 0.5 and 1 mg TP masculinizes female offspring without greatly affecting pup viability or pregnancy of the dam. This study provides a useful model for in utero testing of environmental androgens for their potential to induce developmental abnormalities.
Wrangham RW et al. Sex differences in the behavioural ecology of chimpanzees in the Gombe National Park, Tanzania. 1980 http://europepmc.org/abstract/med/6934308
All-day observations of focal individuals were analysed to compare grouping and ranging patterns and the proportion of time spent feeding by females and males; sexually receptive females were not included. Females spent most of their time alone, whereas males spent most of their time in parties with other males. Females travelled shorter distances than males, and spent their time in smaller core areas: when they joined parties, however, they often travelled outside their normal core areas. Grouping and ranging patterns appear to be related to foraging strategies in different ways in each sex. Females often joined parties for a short time only (< 1 1/2 h), apparently at rich food sources. Males tended to stay for longer, even though they then spent less time feeding than when alone. Spending all day in a party was associated with reduced feeding time for both sexes, but on these days ranging patterns differed between the sexes because males, but not females, travelled further when in parties. The results support the idea that the form of the chimpanzee social system is determined by the interaction of two different strategies: females attempt to forage so as to maximize net energy intake, while males sacrifice an optimal foraging strategy for the sake of reproductive competition.
Smith, Paul Writing, General Knowledge, and Postmodern Anthropology 1999 http://theory.eserver.org/anthropology.html
Sparks et al A reassessment of human cranial plasticity: Boas revisited http://www.pnas.org/content/99/23/14636.abstract?ijkey=f3uGSmr3wB0r.
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