Sex Differences In Sexuality Research Articles

Reactions of Boys and Girls to Sexual Abuse and to Sexual Encounters with Peers.

To understand the etiology and consequences of child sexual abuse it is important to study the victims' subjective reactions to such incidents. Because researchers have not been able to survey children about sexual abuse, not much is known about how subjective reactions are related to gender, age, age difference, and the social relationship between the offender and victim. The present study fills this gap using data gathered from a large, nationally representative sample of Finnish children ages 11 to 17 (N = 32,145). Analyses of abuse are based on a sample of 1520 children (78% girls), while analyses of peer sexual experiences are based on a sample of 3551 children (55% girls). Multivariate analyses adjusted for the use of coercion, the intimacy of the sexual experience, and other incident characteristics. It was hypothesized that, as a result of sex differences in sexuality and attitudes toward deviant behavior, girls are more sensitive than boys to age and age difference. Three findings supported the hypothesis: (1) girls were more likely than boys to have a negative reaction to sexual encounters regardless of the age difference; (2) for girls, age was negatively associated with the likelihood of a negative reaction, but age had no effect for boys; and (3) girls reacted negatively to age difference while boys did not. However, girls did not react more negatively unless the offender was at least eight years older. The results highlight the susceptibility of adolescent boys to encounters with older women. They further suggest that ignoring the role of the victim limits understanding of the vulnerability of young people to sexual abuse.

Singles of both sexes expedite reproduction: Shifts in sexual-timing strategies before and after the typical age of female menopause

Abstract How do singles' strategies for engaging in sexual activity with a new partner vary across the adult lifespan? Using three large and independent demographically representative cross-sectional samples of heterosexual single adults in the U.S., we found that females approaching the typical age of menopause became less likely to establish relationship exclusivity prior to sexual activity with a new partner. However, after the typical age of menopausal onset, females returned to earlier levels of commitment choosiness. These changes in commitment choosiness surrounding the age of menopause were consistent across two studies (including a larger dataset combining two samples). Findings suggest that single females approaching menopause—a major life history milestone—alter their behavior to achieve reproductively relevant partnering goals but abandon this mating strategy once the typical reproductive period has ended. Males exhibited similar, though attenuated, changes in expected relationship commitment before sexual activity during midlife as well. Age-related changes in commitment corresponded with the amount of stress expressed regarding one's “biological clock”. However, reduced commitment choosiness did not vary with frequency of sexual thoughts, frequency of sexual behaviors, or external pressures to find a romantic partner. Results are discussed in terms of life history theory and sex differences in sexuality.

The Ape That Thought It Was a Peacock: Does Evolutionary Psychology Exaggerate Human Sex Differences?

This article looks at the evolution of sex differences in sexuality in human beings and asks whether evolutionary psychology sometimes exaggerates these differences. According to a common understanding of sexual selection theory, females in most species invest more than males in their offspring, and as a result, males compete for as many mates as possible, whereas females choose from among the competing males. The males-compete/females-choose (MCFC) model applies to many species but is misleading when applied to human beings. This is because males in our species commonly contribute to the rearing of the young, which reduces the sex difference in parental investment. Consequently, sex differences in our species are relatively modest. Rather than males competing and females choosing, humans have a system of mutual courtship: Both sexes are choosy about long-term mates, and both sexes compete for desirable mates. We call this the mutual mate choice (MMC) model. Although much of the evolutionary psychology literature is consistent with the MMC model, the traditional MCFC model exerts a strong influence on the field, distorting the emerging picture of the evolved sexual psychology of Homo sapiens. Specifically, it has led to the exaggeration of the magnitude of human sex differences, an overemphasis on men's short-term mating inclinations, and a relative neglect of male mate choice and female mate competition. We advocate a stronger focus on the MMC model.

A Reexamination of Sex Differences in Sexuality

Recent evidence seems to call into question long-established findings of sex differences in sexuality, such as differences in mate preferences and desires for casual sex. In this article, we place new findings in a broader evidence-based context and show that they confirm previous perspectives on human mating. A wealth of evidence from real-world studies of actual mate choice and marital dynamics supports evolutionary mate-preference predictions. Converging evidence from patterns of extradyadic sex, mate poaching, sexual fantasies, pornography consumption, postcoital regret, sociosexual attitudes, and willingness to engage in casual sex supports the view that men and women have distinct short-term mating psychologies. This article highlights the fact that good science requires a constant re-evaluation of old truths and the proper placement of new studies in broad evidentiary contexts.

Sex Differences in Sexual Desires and Attitudes in Norwegian Samples

Despite highly replicable predictable differences between the sexes on various sexual desires and attitudes, critics of evolutionary perspectives argue against the biological origins of such differences, highlighting cultural explanations. Critics suggest that there are no cross-cultural evolutionary predictable, systematic differences. Eagly and Wood (1999) suggest that in egalitarian cultures sex differences will be small or disappear. We tested whether Trivers’ (1972) Parental Investment Theory and Buss and Schmitt’s (1993) Sexual Strategies Theory predicted sex differences in sexuality within samples of students (N=1072) in egalitarian Norway. We expected similar interest in long-term relationships, but that females seek short-term partners less than males. Furthermore, males were expected to have less restricted sociosexuality, fantasize more, take more initiative to sex and be less satisfied with frequency of sex. The predictions were supported in the evolutionarily-predicted directions. Clinical consequences of claiming there are no sex differences in sexuality, when indeed they exist, are discussed

Sexuality and partner selection: Sex differences among college students

Seven hypotheses regarding sex differences in sexuality and partner selection were derived from evolutionary theory and tested among 400 college students. Subjects viewed color photographs of live models dressed in appropriate costumes and paired with descriptions of three potentially datable social types recognizable to college students. A MANOVA revealed significant sex differences in reported willingness to have sexual relations with stimulus persons compared to willingness to engage in higher-investment relationships, and in the effects of stimulus persons' status and physical attractiveness in determining thresholds of initial acceptability. Subjects also responded to the Attitudes Toward Women Scale (AWS), the Sociosexual Orientation Inventory, and statements concerning prospective spouses' relative income, occupational prestige, and physical attractiveness. Regression analyses revealed that males with more economic resources had more sex partners, lower AWS scores, and emphasized prospective spouses' physical attractiveness more and their socioeconomic status less than did their lessaffluent peers. Economic resources and AWS scores did not predict females' sexual behavior. Results from the MANOVA and the regressions suggested that the reported overlap of male and female selection criteria in higher-investment relationships masks sexual dimorphism in the process, criteria, and motivations underlying sexual attraction, mate evaluation, and selection.

Empirical tests of sexual selection theory: Predictions of sex differences in onset, intensity, and time course of sexual arousal

An evolutionary model of sexual behavior was used to generate predictions about sex differences in sexual arousal. Survey instruments were used to test these predictions with 388 adolescents, aged 12-18, from varying socioeconomic strata and geographic regions. Boys reported that their first arousal occurred at the start of puberty or before, usually in response to a visual stimulus, whereas girls generally reported first arousal as occurring 2-3 or more years after puberty, within a social/romantic context. The modal boy reported sexual arousal as occurring several times daily, the modal girl once or twice a week. Boys reported their arousal to be more discriminable, of greater intensity, and more distracting than the girls'. The sexes differed in attitudes related to sexual behavior. However, when reporting emotions and feelings coterminous with sexual arousal, the sexes did not differ. Retrospective college samples of 262 students from West Coast colleges replicated the adolescent data. A survey of 280 East Coast college students found that women's sexual arousal was significantly more partner-dependent than men's. Results were interpreted as supporting evolutionary models of sex differences in sexuality.

Sex differences in sexuality among medical students: Effects of increasing socioeconomic status

Research has consistently shown that, compared to men, women are more cautious and selective and maintain greater marital aspirations in entering and maintaining sexual relationships. One explanation of this sex difference is that women have traditionally had inferior access to earning power and social status and consequently were forced to acquire socioeconomic status (SES) through their choice of marriage partners. A contrasting view is that this difference is a component of the basic sex difference identified in the Kinsey studies: Men are more likely than women to dissociate coitus from emotional attachment and to desire and seek coitus with a variety of partners. These two explanations were explored in open-ended interviews with matched samples of 20 male and 20 female medical students. The results were more consistent with the perspective of basic sex differences than with the differential resources explanation. Increasing female SES does not appear to eliminate or even substantially reduce this sex difference. Increasing SES tends to enlarge the pool of acceptable, available sexual and marital partners for men while it tends to reduce the pool for women. Increasing SES thus tends to have different effects on men and women and may cause sex differences in the tendency to associate coitus with emotional attachments and marital aspirations to be more, rather than less, apparent. Extensive case data with verbatim quotations are presented to reveal the emotions and desires underlying subjects' overt behavior.

A comparison of evolutionary and environmental theories of erotic response part II: Empirical arenas

Areas of empirical strength for socialization and sociobiology theories are critically reviewed. Sociobiology has little to say about erotic mechanisms that are uniquely human, though ethology has begun to address the question through cross‐cultural research. The areas of incest avoidance and connections between sex and aggression are viewed as unsubstantiated, either theoretically or empirically. A connection between sex and love is viewed as more likely, and survey, though not laboratory, research supports it. A classical conditioning theory of sexuality is presented, and its relevance to constructs of socialization theory is sketched. Empirical data relevant to sociobiological analyses of sex differences in sexuality are reviewed. Human size dimorphism is as yet not clearly interpretable. The research paradigms of aberrant hormone effects and response to novelty have not yielded clear or compelling data to date. Results from survey research about homosexual lifestyles and the details of sex differences...

Sex differences in sexuality: what is their relevance to sex roles?

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Précis ofThe evolution of human sexuality

AbstractPatterns in the data on human sexuality support the hypothesis that the bases of sexual emotions are products of natural selection. Most generally, the universal existence of laws, rules, and gossip about sex, the pervasive interest in other people's sex lives, the widespread seeking of privacy for sexual intercourse, and the secrecy that normally permeates sexual conduct imply a history of reproductive competition. More specifically, the typical differences between men and women in sexual feelings can be explained most parsimoniously as resulting from the extraordinarily different reproductive opportunities and constraints males and females normally encountered during the course of evolutionary history. Men are more likely than women to desire multiple mates; to desire a variety of sexual partners; to experience sexual jealousy of a spouse irrespective of specific circumstances; to be sexually aroused by the sight of a member of the other sex; to experience an autonomous desire for sexual intercourse; and to evaluate sexual desirability primarily on the bases of physical appearance and youth.The evolutionary causes of human sexuality have been obscured by attempts to find harmony in natural creative processes and human social life and to view sex differences as complementary. The human female's capacity for orgasm and the loss of estrus, for example, have been persistently interpreted as marriage-maintaining adaptations. Available evidence is more consistent with the view that few sex differences in sexuality are complementary, that many aspects of sexuality undermine marriage, and that sexuality is less a unifying than a divisive force in human affairs.

The Evolution of Human Sexuality: The Latest Word and the LastThe Evolution of Human Sexuality.Donald Symons

Previous articleNext article No AccessNew Biological BooksThe Evolution of Human Sexuality: The Latest Word and the Last The Evolution of Human Sexuality. Donald Symons Sarah Blaffer HrdySarah Blaffer Hrdy Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 54, Number 3Sep., 1979 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/411297 Views: 27Total views on this site Citations: 38Citations are reported from Crossref Copyright 1979 Stony Brook Foundation, Inc.PDF download Crossref reports the following articles citing this article:Andrea Sisti, Negaar Aryan, Payam Sadeghi What is Beauty?, Aesthetic Plastic Surgery 45, no.55 (May 2021): 2163–2176.https://doi.org/10.1007/s00266-021-02288-2Candace Jasmine Black, Emily Anne Patch, Desirae Taylor Female Orgasm and In-Pair Copulation, (Apr 2021): 3027–3034.https://doi.org/10.1007/978-3-319-19650-3_3665Candace Jasmine Black, Emily Anne Patch, Desirae Taylor Female Orgasm and In-Pair Copulation, (Jun 2019): 1–8.https://doi.org/10.1007/978-3-319-16999-6_3665-1Rebecca M. Stumpf Book review, American Journal of Physical Anthropology 144, no.11 (Oct 2010): 166–167.https://doi.org/10.1002/ajpa.21410Jocelyn Bosley From Monkey Facts to Human Ideologies: Theorizing Female Orgasm in Human and Nonhuman Primates, 1967–1983 Bosley, Signs: Journal of Women in Culture and Society 35, no.33 (Jul 2015): 647–671.https://doi.org/10.1086/648515Erika Lorraine Milam, Gillian R. Brown, Stefan Linquist, Steve Fuller, Elisabeth A Lloyd Sometimes an Orgasm is Just an Orgasm, Metascience 15, no.33 (Sep 2006): 399–435.https://doi.org/10.1007/s11016-006-9032-2Joseph H. Manson Female mate choice in primates, Evolutionary Anthropology: Issues, News, and Reviews 3, no.66 (Jun 2005): 192–195.https://doi.org/10.1002/evan.1360030605Meredith F. Small The evolution of female sexuality and mate selection in humans, Human Nature 3, no.22 (Jun 1992): 133–156.https://doi.org/10.1007/BF02692250Colleen B. Cohen, Frances E. Mascia‐Lees Lasers in the jungle: Reconfiguring questions of human and non‐human primate sexuality, Medical Anthropology 11, no.44 (Jul 1989): 351–366.https://doi.org/10.1080/01459740.1989.9966003Saroj B. Datta Female primates: Studies by women primatologists, Ethology and Sociobiology 6, no.33 (Jan 1985): 191–192.https://doi.org/10.1016/0162-3095(85)90032-9 Donna J. Haraway Primatology is Politics by Other Means, PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association 1984, no.22 (Oct 2015): 489–524.https://doi.org/10.1086/psaprocbienmeetp.1984.2.192523SARAH BLAFFER HRDY, GEORGE C. WILLIAMS Behavioral Biology and the Double Standard, (Jan 1983): 3–17.https://doi.org/10.1016/B978-0-12-735950-2.50006-2Donald Symons Précis of The evolution of human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 171–181.https://doi.org/10.1017/S0140525X0000412XJohn Alcock Beyond the sociobiology of sexuality: predictive hypotheses, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 181–182.https://doi.org/10.1017/S0140525X00004131Irwin S. Bernstein Motives, intentions, science, and sex, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 182–183.https://doi.org/10.1017/S0140525X00004143Donald A. Dewsbury Methods in the two sociobiologies, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 183–184.https://doi.org/10.1017/S0140525X00004155Milton Diamond The biosocial evolution of human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 184–186.https://doi.org/10.1017/S0140525X00004167H. J. Eysenck Sociobiology - standing on one leg, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 186–186.https://doi.org/10.1017/S0140525X00004179Ted L. Huston, Gilbert Geis Forcible rape and human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 186–187.https://doi.org/10.1017/S0140525X00004180Michael T. Ghiselin Is sex sufficient?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 187–189.https://doi.org/10.1017/S0140525X00004192Jack P. Hailman Fitness, function, fidelity, fornication, and feminine philandering, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 189–189.https://doi.org/10.1017/S0140525X00004209Julia R. Heiman Selecting for a sociobiological fit, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 189–190.https://doi.org/10.1017/S0140525X00004210Mark R. Hoffman An interactionist perspective on human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 190–191.https://doi.org/10.1017/S0140525X00004222Glenn E. King Pair bonding and proximal mechanisms, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 191–192.https://doi.org/10.1017/S0140525X00004234Michael E. Lamb On the origins and implications of sex differences in human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 192–193.https://doi.org/10.1017/S0140525X00004246J. B. Lancaster, C. S. Lancaster The division of labor and the evolution of human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 193–193.https://doi.org/10.1017/S0140525X00004258W. C. McGrew The proper study of sociobiological mankind is sex, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 193–194.https://doi.org/10.1017/S0140525X0000426XDiane McGuinness Male and female choice in human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 194–195.https://doi.org/10.1017/S0140525X00004271G. Mitchell Sex differences and intent, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 195–196.https://doi.org/10.1017/S0140525X00004283Mark Ridley Konrad Lorenz and Humpty Dumpty: some ethology for Donald Symons, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 196–196.https://doi.org/10.1017/S0140525X00004295Michael Ruse Is science sexist?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 197–198.https://doi.org/10.1017/S0140525X00004301Donald Stone Sade Human sexuality: hints for an alternative explanation, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 198–199.https://doi.org/10.1017/S0140525X00004313H.D. Steklis Problems of comparative primate sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 199–200.https://doi.org/10.1017/S0140525X00004325Dorothy Tennov The clarification of proximate mechanisms, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 200–200.https://doi.org/10.1017/S0140525X00004337J. Richard Udry Female sexual adaptability: a consequence of the absence of natural selection among females, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 201–202.https://doi.org/10.1017/S0140525X00004350Shirley Weitz Sex differences in sexuality: what is their relevance to sex roles?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 202–202.https://doi.org/10.1017/S0140525X00004362Richard E. Whalen Evolutionary causation: how proximate is ultimate?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 202–203.https://doi.org/10.1017/S0140525X00004374Donald Symons The evolution of human sexuality revisited, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 203–214.https://doi.org/10.1017/S0140525X00004386

Reply to Hailman

Previous articleNext article No AccessLetters to the EditorsReply to HailmanAnthony FergusonAnthony Ferguson Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 111, Number 977Jan. - Feb., 1977 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/283148 Views: 2Total views on this site Citations: 26Citations are reported from Crossref Copyright 1977 The University of ChicagoPDF download Crossref reports the following articles citing this article:Donald Symons Précis of The evolution of human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 171–181.https://doi.org/10.1017/S0140525X0000412XJohn Alcock Beyond the sociobiology of sexuality: predictive hypotheses, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 181–182.https://doi.org/10.1017/S0140525X00004131Irwin S. Bernstein Motives, intentions, science, and sex, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 182–183.https://doi.org/10.1017/S0140525X00004143Donald A. Dewsbury Methods in the two sociobiologies, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 183–184.https://doi.org/10.1017/S0140525X00004155Milton Diamond The biosocial evolution of human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 184–186.https://doi.org/10.1017/S0140525X00004167H. J. Eysenck Sociobiology - standing on one leg, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 186–186.https://doi.org/10.1017/S0140525X00004179Ted L. Huston, Gilbert Geis Forcible rape and human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 186–187.https://doi.org/10.1017/S0140525X00004180Michael T. Ghiselin Is sex sufficient?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 187–189.https://doi.org/10.1017/S0140525X00004192Jack P. Hailman Fitness, function, fidelity, fornication, and feminine philandering, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 189–189.https://doi.org/10.1017/S0140525X00004209Julia R. Heiman Selecting for a sociobiological fit, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 189–190.https://doi.org/10.1017/S0140525X00004210Mark R. Hoffman An interactionist perspective on human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 190–191.https://doi.org/10.1017/S0140525X00004222Glenn E. King Pair bonding and proximal mechanisms, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 191–192.https://doi.org/10.1017/S0140525X00004234Michael E. Lamb On the origins and implications of sex differences in human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 192–193.https://doi.org/10.1017/S0140525X00004246J. B. Lancaster, C. S. Lancaster The division of labor and the evolution of human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 193–193.https://doi.org/10.1017/S0140525X00004258W. C. McGrew The proper study of sociobiological mankind is sex, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 193–194.https://doi.org/10.1017/S0140525X0000426XDiane McGuinness Male and female choice in human sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 194–195.https://doi.org/10.1017/S0140525X00004271G. Mitchell Sex differences and intent, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 195–196.https://doi.org/10.1017/S0140525X00004283Mark Ridley Konrad Lorenz and Humpty Dumpty: some ethology for Donald Symons, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 196–196.https://doi.org/10.1017/S0140525X00004295Michael Ruse Is science sexist?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 197–198.https://doi.org/10.1017/S0140525X00004301Donald Stone Sade Human sexuality: hints for an alternative explanation, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 198–199.https://doi.org/10.1017/S0140525X00004313H.D. Steklis Problems of comparative primate sexuality, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 199–200.https://doi.org/10.1017/S0140525X00004325Dorothy Tennov The clarification of proximate mechanisms, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 200–200.https://doi.org/10.1017/S0140525X00004337J. Richard Udry Female sexual adaptability: a consequence of the absence of natural selection among females, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 201–202.https://doi.org/10.1017/S0140525X00004350Shirley Weitz Sex differences in sexuality: what is their relevance to sex roles?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 202–202.https://doi.org/10.1017/S0140525X00004362Richard E. Whalen Evolutionary causation: how proximate is ultimate?, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 202–203.https://doi.org/10.1017/S0140525X00004374Donald Symons The evolution of human sexuality revisited, Behavioral and Brain Sciences 3, no.22 (Feb 2010): 203–214.https://doi.org/10.1017/S0140525X00004386