On the origins of sexual dimorphism in butterflies

The processes governing the evolution of sexual dimorphism provided a foundation for sexual selection theory. Two alternative processes, originally proposed by Darwin and Wallace, differ primarily in the timing of events creating the dimorphism. In the process advocated by Darwin, a novel ornament arises in a single sex, with no temporal separation in the origin and sex-limitation of the novel trait. By contrast, Wallace proposed a process where novel ornaments appear simultaneously in both sexes, but are then converted into sex-limited expression by natural selection acting against showy coloration in one sex. Here, we investigate these alternative modes of sexual dimorphism evolution in a phylogenetic framework and demonstrate that both processes contribute to dimorphic wing patterns in the butterfly genera Bicyclus and Junonia . In some lineages, eyespots and bands arise in a single sex, whereas in other lineages they appear in both sexes but are then lost in one of the sexes. In addition, lineages displaying sexual dimorphism were more likely to become sexually monomorphic than they were to remain dimorphic. This derived monomorphism was either owing to a loss of the ornament (‘drab monomorphism’) or owing to a gain of the same ornament by the opposite sex (‘mutual ornamentation’). Our results demonstrate the necessity of a plurality in theories explaining the evolution of sexual dimorphism within and across taxa. The origins and evolutionary fate of sexual dimorphism are probably influenced by underlying genetic architecture responsible for sex-limited expression and the degree of intralocus sexual conflict. Future comparative and developmental work on sexual dimorphism within and among taxa will provide a better understanding of the biases and constraints governing the evolution of animal sexual dimorphism.

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The production of excretory-secretory molecules from Heligmosomoides polygyrus bakeri fourth stage larvae varies between mixed and single sex cultures

Parasites & Vectors ◽

10.1186/s13071-021-04613-9 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Marta Maruszewska-Cheruiyot ◽

Ludmiła Szewczak ◽

Katarzyna Krawczak-Wójcik ◽

Magdalena Głaczyńska ◽

Katarzyna Donskow-Łysoniewska

Keyword(s):

Sex Pheromones ◽

Pheromone Communication ◽

Larval Culture ◽

Heligmosomoides Polygyrus ◽

Single Sex ◽

Opposite Sex ◽

Potential Vaccine ◽

Immunomodulatory Properties ◽

Therapeutic Compounds ◽

Immunomodulatory Potential

Abstract Background Excretory-secretory (ES) products are crucial in maintaining helminths in the host. Consequently, the proteins of ES are potential vaccine molecules and potential therapeutic agents for autoimmune diseases. Heligmosomoides polygyrus bakeri, a gastrointestinal parasite of mice, is a model of hookworm infection in humans. ES produced by both sexes of H. polygyrus bakeri L4 stage cultured separately shows different immunomodulatory properties than ES obtained when both sexes are cultured together. Accordingly, the objective of this study was to identify and compare the excretory-secretory molecules from single-sex and mixed cultures. Methods The composition of ES of male and female L4 stage nematodes in the presence (cultured together) or absence (cultured alone) of the opposite sex was examined. Proteins were identified using mass spectrometry. The functions of identified proteins were explored with Blast2GO. Results A total of 258 proteins derived from mixed larval culture in the presence of sex pheromones were identified, 160 proteins from pure female cultures and 172 from pure male cultures. Exposure of nematodes to the sex pheromones results in abundant production of proteins with immunomodulatory properties such as Val proteins, acetylcholinesterases, TGF-β mimic 9 and HpARI. Proteins found only in ES from mixed larval cultures were TGF-β mimics 6 and 7 as well as galectin. Conclusions The presence of the opposite sex strongly influences the composition of ES products, probably by chemical (pheromone) communication between individuals. However, examination of the composition of ES from various conditions gives an opportunity for searching for new potentially therapeutic compounds and anthelminthics as well as components of vaccines. Manipulation of the nematode environment might be important for the studies on the immunomodulatory potential of nematodes.

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Sexual Dimorphism in Colon Cancer

Frontiers in Oncology ◽

10.3389/fonc.2020.607909 ◽

2020 ◽

Vol 10 ◽

Author(s):

Maria Abancens ◽

Viviana Bustos ◽

Harry Harvey ◽

Jean McBryan ◽

Brian J. Harvey

Keyword(s):

Sexual Dimorphism ◽

Older Women ◽

Epithelial Mesenchymal Transition ◽

Protective Role ◽

Survival Outcome ◽

The Novel ◽

Sex Steroid Hormone ◽

Mesenchymal Transition ◽

Vegf Signaling ◽

Kv Channels

A higher incidence of colorectal cancer (CRC) is found in males compared to females. Young women (18–44 years) with CRC have a better survival outcome compared to men of the same age or compared to older women (over 50 years), indicating a global incidence of sexual dimorphism in CRC rates and survival. This suggests a protective role for the sex steroid hormone estrogen in CRC development. Key proliferative pathways in CRC tumorigenesis exhibit sexual dimorphism, which confer better survival in females through estrogen regulated genes and cell signaling. Estrogen regulates the activity of a class of Kv channels (KCNQ1:KCNE3), which control fundamental ion transport functions of the colon and epithelial mesenchymal transition through bi-directional interactions with the Wnt/β-catenin signalling pathway. Estrogen also modulates CRC proliferative responses in hypoxia via the novel membrane estrogen receptor GPER and HIF1A and VEGF signaling. Here we critically review recent clinical and molecular insights into sexual dimorphism of CRC biology modulated by the tumor microenvironment, estrogen, Wnt/β-catenin signalling, ion channels, and X-linked genes.

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Coeducation and Sex Roles

Australian Journal of Education ◽

10.1177/000494418603000202 ◽

1986 ◽

Vol 30 (2) ◽

pp. 117-131 ◽

Cited By ~ 7

Author(s):

Mary B. Harris

Keyword(s):

High School ◽

University Students ◽

Sexual Intercourse ◽

Sex Roles ◽

Natural Attitude ◽

Single Sex ◽

Happy Marriage ◽

Opposite Sex ◽

Males And Females ◽

Coeducational High Schools

In order to test conflicting hypotheses about the effects of coeducational versus single-sex schooling, 538 first-term Australian university students who had attended single sex or coeducational high schools were compared on a number of variables relating to sex roles. Those from the two types of schools did not differ significantly on the Australian Sex Roles Inventory or on a measure of nontraditional attitudes towards sex roles, although males and females differed in predictable ways. Most subjects, particularly those from coeducational schools, felt that coeducational schools are preferable and lead to a more natural attitude towards the opposite sex. Subjects from coeducational rather than single-sex schools said that they had more opposite-sex friends in high school and were more likely to feel that their school helped rather than hindered their everyday relations with the opposite sex and their chances for a happy marriage. However subjects did not feel that boys and girls learn or behave better in coeducational schools, and there were no differences in the percentages of subjects from the two types of schools who reported having had sexual intercourse or been in love while in high school. The single-sex schools attended tended to differ from the coeducational ones in being smaller, more urban, and more likely to be selective, which made comparisons difficult to interpret. Nevertheless it seems reasonable to conclude that coeducational schooling, at least for this selective sample, may have some advantages in fostering interactions with the opposite sex.

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MORAL VALUE IN NOVEL TASAWUF LOVE KARYA M. HILMI AS'AD

Jurnal Tarbiyah Jurnal Ilmiah Kependidikan ◽

10.18592/tarbiyah.v6i1.1305 ◽

2017 ◽

Vol 6 (1) ◽

Author(s):

Wulandari Ramadania

Keyword(s):

Social Life ◽

Moral Values ◽

The Novel ◽

Human Beings ◽

Moral Value ◽

Opposite Sex ◽

Social Messages ◽

Relationship Of ◽

The Relationship ◽

Descriptive Method

ABSTRACTThe moral value conveyed by the author to the reader through works of fiction especially novels is useful and useful to the reader. This study aims to describe the moral values associated with social messages and expose the moral values associated with the religious message contained in the novel Tasawuf Cinta by M. Hilmi As'ad. The method used in this research is analytic descriptive method. The results of this study indicate the moral values associated with social messages are: (1) social in social life; (2) relations between human beings of religion, and (3) association between the opposite sex. The moral values associated with the religious message are: (1) the relationship of man and God; (2) human nature and conscience; (3) the personal freedom that man possesses; And (4) the dignity and dignity of each individual.Keywords: moral value, novel

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Profil Perempuan Urban dalam Novel Celebrity Wedding karya Alia Azalea

Jurnal Bahasa dan Sastra ◽

10.24036/jbs.v8i2.109682 ◽

2020 ◽

Vol 8 (2) ◽

pp. 116

Author(s):

Rani Anggraini ◽

Hasanuddin WS Hasanuddin WS

Keyword(s):

Qualitative Research ◽

Family Environment ◽

Urban Women ◽

The Novel ◽

Human Beings ◽

Female Characters ◽

Research Results ◽

The Family ◽

Basic Attitude ◽

Opposite Sex

This study aims to describe the profile of urban women in the metropolitan novel Alia Azalea Celebrity Wedding based on basic attitudes (1) love, (2) beauty, (3) suffering, (4) justice, (5) view of life, (6) responsibility, (7) anxiety, (8) hope. This type of research is qualitative research using descriptive methods. The data in this study are in the form of words, phrases, clauses, sentences which can be formulated as a profile of urban women. Based on the research results, it can be concluded that there are eight basic human attitudes towards female characters in the novel. Eight basic attitude patterns of love that are oriented towards the balance between love for family, fellow human beings and the opposite sex, beauty is oriented towards spiritual beauty, suffering is oriented towards suffering as a trial, justice is oriented towards honesty, view of life is oriented towards a view of life that comes from reflection, responsibility Responsibility is oriented towards self-responsibility, anxiety is oriented towards anxiety in the form of uncertainty, and expectations are oriented towards acceptance expectations in the family environment from Revel.

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Reproductive strategy, sexual development and attraction to facial characteristics

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2006.1936 ◽

2006 ◽

Vol 361 (1476) ◽

pp. 2143-2154 ◽

Cited By ~ 35

Author(s):

R. Elisabeth Cornwell ◽

Miriam J Law Smith ◽

Lynda G Boothroyd ◽

Fhionna R Moore ◽

Hasker P Davis ◽

...

Keyword(s):

Sexual Dimorphism ◽

Sexual Maturation ◽

Sexual Development ◽

Reproductive Strategy ◽

Early Life ◽

Early Age ◽

Successful Implementation ◽

Sexually Dimorphic ◽

First Sex ◽

Opposite Sex

Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on the rapidity of their sexual development. Fast developing individuals prefer opposite-sex partners with an increased level of sexually dimorphic facial characteristics.

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Short Article: Are Attractive Facial Characteristics Peculiar to the Sex of a Face?

Quarterly Journal of Experimental Psychology ◽

10.1080/17470210802592030 ◽

2009 ◽

Vol 62 (5) ◽

pp. 833-843 ◽

Cited By ~ 2

Author(s):

Sarah J. Casey ◽

Marion Mernagh ◽

Fiona N. Newell

Keyword(s):

Information Processing ◽

Sexual Dimorphism ◽

Mate Choice ◽

Mate Selection ◽

General Information ◽

Short Article ◽

Face Images ◽

The Face ◽

Opposite Sex ◽

Opposite Face

Preferences for faces are thought to be the result of either general adaptations for mate selection, and thus influenced by sexual dimorphism, or mechanisms of general information processing and thus nonspecific to faces. If mate choice determines face preference then it should follow that the sex of a face should affect attractiveness judgements. To test this idea we used image morphing to generate three versions of face images: original, opposite sex, and antiface. First we established that the sex of the face was identifiable in our images. We then collected attractiveness ratings for the three face types. We found that attractiveness ratings to the original faces were correlated with, and did not differ significantly between, ratings to the opposite-sex faces. However, ratings for either the original or opposite face types were not correlated with and were significantly lower than ratings to the antifaces. Our findings failed to support the idea that attractiveness is related to sexual dimorphism in faces alone but suggest instead that other more generic factors influence preferences for all faces.

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Maternal Serum Steroid Levels Are Unrelated to Fetal Sex: A Study in Twin Pregnancies

Twin Research and Human Genetics ◽

10.1375/twin.8.2.173 ◽

2005 ◽

Vol 8 (2) ◽

pp. 173-177 ◽

Cited By ~ 17

Author(s):

Celina C. C. Cohen-Bendahan ◽

Stephanie H. M. van Goozen ◽

Jan K. Buitelaar ◽

Peggy T. Cohen-Kettenis

Keyword(s):

Prenatal Exposure ◽

Twin Pair ◽

Maternal Serum ◽

The Other ◽

Male Fetus ◽

Female Fetus ◽

Single Sex ◽

Opposite Sex ◽

The Relationship ◽

Twin Pregnancies

AbstractIncreased prenatal exposure to testosterone (T) in females of an opposite-sex (OS) twin pair may have an effect on the development of sex-typical cognitive and behavioral patterns. The prenatal exposure to T due to hormone transfer in OS twin females may occur in two ways, one directly via the feto–fetal transfer route within the uterus, the other indirectly through maternal–fetal transfer and based in the maternal–fetal compartment. Although some studies in singletons indeed found that women pregnant with a male fetus have higher T levels during gestation than women pregnant with a female fetus, many other studies could not find any relation between the sex of the fetus and maternal serum steroid levels. Therefore at present it is unclear whether a pregnant woman bearing a male has higher levels of T than a woman bearing a female. Up to this point, no-one has investigated this issue in twin pregnancies. We examined the relationship between maternal serum steroid levels and sex of fetus in 17 female–female, 9 male–male and 29 OS twin pregnancies. No differences were observed between the maternal serum steroid levels of women expecting single-sex and mixed-sex offspring. It is concluded that the source of prenatal T exposure in females probably comes from the fetal unit, which is the direct route of fetal hormone transfer.

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Attention to Sex in Psychological Research as Related to Journal Policy and Author Sex

Psychology of Women Quarterly ◽

10.1111/j.1471-6402.1979.tb00706.x ◽

1979 ◽

Vol 4 (2) ◽

pp. 175-184 ◽

Cited By ~ 3

Author(s):

Claire Etaugh ◽

Deborah Bohn Spandikow

Keyword(s):

Sex Differences ◽

Child Development ◽

Developmental Psychology ◽

Editorial Policy ◽

Psychological Research ◽

Senior Author ◽

Chi Square ◽

Female Authors ◽

Single Sex ◽

Opposite Sex

From 1969 to 1974, Developmental Psychology, but not Child Development, specified that authors analyze for sex differences. The authors examined 503 studies published in Child Development and Developmental Psychology in 1971 and 1975. Sex of senior author, subjects and experimenter(s) were recorded for each study. If subjects of both sexes were used, the presence or absence of the following were noted: (a) analysis of sex differences; (b) hypotheses regarding sex differences; (c) mention of subjects' sex in the abstract. For single-sex-subject studies, mention of subjects' sex in the discussion or conclusion was noted. Using these data as dependent variables, chi-square analyses were performed comparing: (a) the two journals; (b) 1971 and 1975 authors; and (c) male and female authors. The findings were: (a) More attention was paid to sex in Developmental Psychology when the journal had a written editorial policy regarding this factor; (b) Evidence was mixed for increasing awareness of sex as a variable between 1971 and 1975; (c) Female authors were more aware of sex than were male authors in 1971 but not in 1975; (d) In both years, authors used own-sex subjects and experimenters more than those of the opposite sex; (e) Developmental psychologists, as compared to psychologists in other areas previously examined, were more sensitive to sex as a variable.

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