Research: Evolutionary Perspectives on Intergenerational Sexuality

This article has been written in standard format mixed with an anthology.

While the evolutionary logic of intergenerational sexual behaviour and hebephilic attraction towards pubertal adolescents of the opposite sex is easily explained by fertility potential of such behaviour (see mentions of hebephilia), the explanation of intergenerational attractions toward prepubertal children (pedophilia/pedosexuality), or adolescent homosexual partners (pederastic inclination), or the very existence of prepubertal child sexuality, is less obvious.

The emergence of such sexuality has several evolutionary explanations with varying degrees of evidence, which come from ethology and neuroscience. There are suggestions that, in our evolutionary past, pedosexual behaviors could have had some evolutionary functions or been an evolutionary by-product of human sexuality development. These explanations may have pragmatic implications for the well-being of both MAPs and minors. "Evolutionary scenarios are not just interesting explanatory “stories,” but can illuminate limits as well as opportunities for intervention" (Del Giudice M., 2014). Here is an attempt to categorize these hypotheses, although they overlap greatly and can hardly be considered separately. Rather, they describe different aspects of a complex evolutionary process.

By-product of lack of success in male sexual competition

One hypothesis is that if a male is unsuccessful in sexual competition for fertile females, and he chronically feels inferior to others and is afraid of other adults, then his sexuality towards adults may be suppressed and redirected towards children, because children do not cause fear, and next to them the male feels his strength and superiority. Male's sexuality is more associated with dominance and this may explain the greater prevalence of attraction to children among men than among women.

Excerpts:

• Medicus, G., Hopf, S. (1990). The Phylogeny of Male/Female Differences in Sexual Behavior. In: Feierman, J.R. (eds) Pedophilia: Biosocial Dimensions Springer, New York, NY. doi:10.1007/978-1-4613-9682-6_5

  "As has been pointed out, adult human sexual behavior with children and adolescents can be understood within the context of dimorphism. Male/ female differences in sexual behavior result at least in part from the different amounts of energy and time each sex expends for reproduction (see Table 4.1). This initial difference produces a difference in the functional proximity of the moods of fear and aggression to sexual mood (see Table 4.11), as well as a difference in the likelihood for active pursuit of sexual opportunities"

  "One of the most consistent psychological correlates that has been identified is that many adult males who are sexually attracted to children and adolescents show manifestations of (real or self-perceived) social inadequacy with peers. Such males may suffer from feelings of anxiety when they consider sexual behavior with an adult partner (Johnston and Johnston, 1986; Panton, 1979; Segal and Marshall, 1985). Because sex and fear are such functionally distant moods in males, many human adult males cannot perform sexual actions when they feel inferior to their sexual partner or when they feel anxious (e.g., Bancroft, 1985; Eicher, 1980). This explanation is in accordance with the previously mentioned male/female dimorphism in the relationship of mood and behavior (see Table 4.11). Because of their small size, lack of experience, and sense of insecurity, children and adolescents of either sex do not arouse feelings of inferiority, fear, and anxiety in adult males. Thus, children and adolescents can become "sexual objects" for males who in sociosexual relations with adults feel inferior or anxious."

• Glenn D. Wilson and David N. Cox. 1983. The Child-Lovers: A Study of Paedophiles in Society. By London: Peter Owen. Pp 132. British Journal of Psychiatry. 1983;143(4):430-430. doi:10.1192/S0007125000200780

  "Examination of the characteristics of children that the paedophiles found most attractive points to the conclusion that the ability to achieve social dominance over the child may be the key to understanding the paedophile’s choice of sex target."

  "Viewed in this way, paedophilia would seem to be one of several alternative adaptations to the problem of lack of success (or perceived inability to succeed) in intermale competition for access to females. It has been often noted by ethologists that the males of any species are thrown into strong Darwinian competition with one another. Those that are most successful monopolise an unequal share of female resources, and the others have to make do with various substitute sexual outlets. Following this model, we would not expect to find any genetic predisposition toward paedophilia per se, but as with homosexuality and certain other sex deviations, some degree of heritability would be mediated by the constitutional basis of dominance versus submissiveness. In other words, paedophiles may inherit their submissive nature, which in turn makes for difficulties in establishing normal sexual roles."

• Connie M. Anderson (1990). "Adolescent/Adult Copulatory Behavior in Nonhuman Primates." In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 324–337). Springer, New York. doi:10.1007/978-1-4613-9682-6_13

  "Adult, subadult, and adolescent females are monopolized by adult male harem-holders, leaving a few adult and all subadult males without adult sexual partners. Under these conditions, males without harems choose a particular juvenile female to follow and display intense parental-like behavior towards her. Eventually, she becomes the first individual in the male's harem, and he begins mating with her at her first estrous swelling. Thus, both parental-like and copulatory motor patterns are directed at the same individual over the course of time and, for a brief period, even simultaneously."

"Nest helper" hypothesis

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The concept of "nest helper", is an explanation of a few individuals within a group being nonreproductive, yet aiding their group's survival. They may be affectionately disposed and caring towards others without reproducing, since this promotes the reproduction of peers who share some of the same genes due to being genetic relatives in the group. Due to sexual competition and the costs of human reproduction, not every individual can reproduce, hence there are indirect genetic benefits of "nest helping" that may overcome benefits of direct reproductive efforts for some individuals. This evolutionary hypothesis applies to both exclusive homosexuality and exclusive pedophilia, although due to a lack of investigation, there is at present little evidence for it (Feierman, 1990).

Excerpts:

• Feierman, Jay R. (1990). Human Erotic Age Orientation: A Conclusion. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 552–566). Springer, New York. doi:10.1007/978-1-4613-9682-6_23

  "Whereas a similar challenge has been met somewhat reasonably in terms of the "nest helper" concept of adult homosexuality, hypothesizing that another type of nest helper would have to erotically love and sexually interact with the children for whom he was caring"

Help in developing sexual ability

For many primates, sexual behavior requires learning. Therefore, in some species, adult primates who have sexual contact with juveniles may help them develop sexual skills. In addition, sex can trigger the onset of fertility. Such a function could have played a role in the human evolutionary past (Dienske, 1990). In some species, this function has built in to that extent that without early sexual experience with an adult an individual grows up unable to conceive.

• Connie M. Anderson (1990). "Adolescent/Adult Copulatory Behavior in Nonhuman Primates". In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 324–337). Springer, New York. doi:10.1007/978-1-4613-9682-6_13

  "Among nonhuman primates, then, sexual interaction between adult females and immature males is universal [...] Adult females do interact sexually with males of all ages, including infants too young to be capable of intromission or ejaculation. Females have little to lose by doing so, since they do not deplete their egg supply by unsuccessful matings and since they are unlikely to be seriously injured in the process. They may also help their immature male relatives by allowing them access to experienced females to practice sexual behavior so that they can perform successfully from the time spermatogenesis begins."

• Feierman, Jay R. (1990). A Biosocial Overview of Adult Human Sexual Behavior with Children and Adolescents. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 8–68). Springer, New York. doi:10.1007/978-1-4613-9682-6_2

  "In the squirrel monkey (Saimin), captivity-raised individuals of both sexes in mixed-sex peer groups were not even able to conceive unless they had been allowed, when they were juveniles, to have sexual contact with opposite-sex adults (Hopf, 1979, personal communication)."

• De Waal, Frans B. M. (1990). Sociosexual behavior used for tension regulation in all age and sex combinations among bonobos. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 378–393). Springer, New York. doi:10.1007/978-1-4613-9682-6_15

  "Thus, juvenile male chimpanzees are attracted to females in estrus, and pubertal females begin to explore sexual contact with older males as soon as their genital swellings develop (van der Weel, 1978; de Waal, 1982; Goodall, 1986). Such intergenerational experience undoubtedly contributes to the development of adequate sexual skills."

Advantage in sexual competition

The emergence of nonexclusive pedophilic interest could be due to males experiencing selection pressure to display affiliative behavior towards minors. Such a display aims to convince fertile females that the male is ready for paternal investment, thus giving advantages in access to the fertile female (Taub, 1990).

Excerpts:

• Taub, David M. (1990). The Functions of Primate Paternalism: A Cross-Species Review. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 338–377). Springer, New York. doi:10.1007/978-1-4613-9682-6_14

  "Why then are these unrelated males forming special affiliations with and investing in these infants? Proponents of this view suggest that males form special relationships with infants as a means whereby they may develop a closer and stronger affiliative relationship with the infant's mother. This enhanced, or special, relationship with the mother, in turn, enhances the male's chances of mating with this female in the future."

Sex as a buffer for aggression

Ethologist Irenäus Eibl-Eibesfeldt suggested that the interconnection between sex and dominance is the basic ("reptilian") way of vertebrate sexuality organization. Aggression and dominance acquired a functional connection with male sexuality due to the fact that aggressive and dominant males tended to win in sexual competition. In contrast, submission was embedded in female sexuality. The submissive posture of the female ready for mating is a stimulus to transform male’s aggressive drive to the sexual drive. This prevents injuries and allows mating to occur. Thus aggression, dominance and submission were sexualized, and sexuality acquired the ability to buffer aggression in hierarchical relationships. (The manifestation of that ability is that the appeasing posture of a defeated enemy in animals often resembles the posture of a female ready to mate). Eibl-Eibesfeldt supposed that it is possible that this function could be partly transferred into the adult-juvenile hierarchical relationship (Eibl-Eibesfeldt, 1990).

Excerpts:

• Eibl-Eibesfeldt, Irenäus (1990). Dominance, Submission, and Love: Sexual Pathologies from the Perspective of Ethology. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 150–175). Springer, New York. doi:10.1007/978-1-4613-9682-6_6

  “Dominance between group members is also expressed by ritualized mounting, and submission, in turn, is expressed by female-type presenting. From these kinds of greeting rituals have evolved behaviors such as those of hamadryas baboons, in which males approaching high-ranking individuals present as if they, the presenters, were females. Their buttocks are hairless and red in mimicry of the female buttocks, thus enhancing the signal value of presenting (Wiclder, 1966, 1967b). The high-ranking individual may mount or just perform the intention to mount in response to the other's presenting. This use by primates of sexual motor patterns to acknowledge dominance rank order has often been interpreted as being equivalent to human homosexuality. This interpretation is an oversimplification. These sexual motor patterns are derived from copulatory behaviors but, then, have acquired a new function related to social hierarchies: mounting serves as an indication of dominance, and presenting serves as an indication of submission, an agonistic buffer in a greeting context”

  “Children have characteristics, such as small size, that facilitate adult males' feeling dominant to them, as occurs in pedosexual behavior.”

Sex for reconciliation and food sharing

The reduction of social tension mediated by sociosexual contact is widespread in the communities of human closest relatives, the Bonobos. The tension arises in situations of competition or inequality referring to any kind of resources such as food, access to reproduction or any interesting stimulus matter. In addition to the reconciliation effect, sexual contacts allow them to willingly share resources with one another. Ethologist Frans de Waal pointed that this mechanism works for individuals of any status, sex and age, including contacts between adults and infants. Via this mechanism, adults share food with juveniles who are not their descendants and are not of reproductive interest. The emergence of this mechanism presumably occurred as a result of an evolutionary shift in relationships between males and females towards the more tolerant and equal in the case of Bonobos (de Waal, 1990). Among most other primates except for humans, cases of adults, especially males, sharing food with another's offspring are quite rare (Mackey, 1990).

Frans de Waal suggests that our ancestor’s sexual behavior may have been similar to Bonobo's. This sex-for-food mechanism then allowed females to exchange sex for male commitment and paternal investment, thus giving rise to the human nuclear family. And subsequently, the very development of the nuclear family led to an increasing restriction of sex functions to heterosexual reproductive bonding only (de Waal, 2006).

Excerpts:

• De Waal, Frans B. M. (1990). Sociosexual behavior used for tension regulation in all age and sex combinations among bonobos. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 378–393). Springer, New York. doi:10.1007/978-1-4613-9682-6_15

  "Typically, upon the introduction of food, the bonobos would become very active, engaging in aggressive competition but also inviting one another for sociosexual contact These contacts appeared to reduce the tension and to allow for food sharing. Thus, it could be demonstrated that subordinate group members more often asserted themselves toward dominant food possessors following a sociosexual contact than without such prior contact (de Waal, 1987). The interaction could even take the form of an exchange, e.g., a female presents to a male who is holding a large bundle of branches and leaves and takes the entire bundle out of his hands immediately following sexual intercourse. On other occasions, sociosexual behavior was used as a reconciliation. The majority of instances of genital massage, for instance, followed aggressive incidents in which the adult male had chased one of the adolescent males. After a couple of minutes, the younger male would return to the aggressor to present his genitals."

  “Sociosexual behavior occurred with equal frequency and equal intensity in all age and sex combinations possible. Intergenerational sex was part of this general pattern. The bonobo's sexual reconciliation and reassurance patterns were described and contrasted with the behavior of the chimpanzee, which virtually lacks this nonreproductive function of sexual behavior. The evolutionary origin of this difference was sought in heterosexual bonding among bonohos in their natural habitat. [...] Coexistence of plural males and females without agonistic competition in mating could be guaranteed by changing the character of sexual behavior into affiliative behavior in which all individuals can participate, and by decreasing the reproductive meaning (Mori, 1984, p.277).[...] This possible evolutionary background of the phenomena observed in bonobos is of relevance in connection with human sexuality, both because of the shared biological ancestry and the fact that heterosexual bonding is characteristic of the human species as well."

  "[T]he most logical pathway by which sexual behavior evolved into a general reassurance mechanism is that this mechanism was first established in the adult male/female relationship, after which it was adopted in other age and sex combinations. In other words, the widespread application of sexual behavior patterns in the bonobo' s social life has its origin in an emphasis on heterosexual bonding (de Waal, 1987). Field research supports this view in that male/female relationships seem closer and more tolerant in bonobos than in chimpanzees."

• de Waal, Frans B. M. (2006). Bonobo Sex and Society. Scientific American, 16, 14-21, doi:10.1038/scientificamerican0606-14sp

  "Ocasionally, the role of sex in relation to food is taken one step further, bringing bonobos very close to humans in their behavior. It has been speculated by anthropologists--including C. Owen Lovejoy of Kent State University and Helen Fisher of Rutgers University--that sex is partially separated from reproduction in our species because it serves to cement mutually profitable relationships between men and women. The human females capacity to mate throughout her cycle and her strong sex drive allow her to exchange sex for male commitment and paternal care, thus giving rise to the nuclear family."

  "This arrangement is thought to be favored by natural selection because it allows women to raise more offspring than they could if they were on their own."

  "Given its peacemaking and appeasement functions, it is not surprising that sex among bonobos occurs in so many different partner combinations, including between juveniles and adults. The need for peaceful coexistence is obviously not restricted to adult heterosexual pairs."

  “In fact, nuclear families are probably incompatible with the diverse use of sex found in bonobos. If our ancestors started out with a sex life similar to that of bonobos, the evolution of the family would have required dramatic change.

  Human family life implies paternal investment, which is unlikely to develop unless males can be reasonably certain that they are caring for their own, not someone elses, offspring. Bonobo society lacks any such guarantee, but humans protect the integrity of their family units through all kinds of moral restrictions and taboos. Thus, although our species is characterized by an extraordinary interest in sex, there are no societies in which people engage in it at the drop of a hat (or a cardboard box, as the case may be). A sense of shame and a desire for domestic privacy are typical human concepts related to the evolution and cultural bolstering of the family."

• Mackey, Wade C. (1990). Adult·Male/Juvenile Association as a Species-Characteristic Human Trait: A Comparative Field Approach. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 299–323). Springer, New York. doi:10.1007/978-1-4613-9682-6_12

  "As pointed out earlier, human adult males share food/provisions with their young, and this sharing by adult males is relatively rare across the zoological kingdom. It is reasonable that the sharing of a most valuable commodity -- food -- is much easier emotionally for the provisioner if the provisioner "likes" the recipient, and conversely, a recipient tends to like someone who feeds him or her, especially during the dependency of preadulthood. Accordingly, the behavioral enhancement of any neurohormonal mechanisms (subtended by the relevant genetic material) that resulted in greater affiliative feelings, toward juveniles, for example, would facilitate food sharing. The facilitation might be further sensitized by the stimulus of those young who are provisioned showing outward signs of affiliation towards the provisioner. Across generations, the increased provisioning of juveniles by adult males would marginally increase those juveniles' viability, thereby increasing those adult males' chances of having descendants. Thus, the alleles in adult males and juveniles that canalized reciprocal adult-male/juvenile affiliative behavior, in general, and the resultant specific adult-male/juvenile association, in particular, would gradually and systematically displace competing alleles that did not facilitate the development of affiliation between adult males and juveniles. In the 20th century, food sharing from human adult males to juveniles has been found to be a universal practice"

Sex as an attachment promoter. Development of paternal investment

In addition to the “reptilian” connection between sex and dominance, Eibl-Eibesfeldt described another way of sexuality organization. That evolutionary later way is the interweaving of sex and attachment, which is typical for birds and some mammals forming long-term reproductive alliances. The ability of males to form attachment and exhibit caring behavior to a sexual partner is highly beneficial for females. Human evolution went through an increase in the maturation time of offspring, which led to huge reproductive costs for females. Thus, there was a particularly strong sexual selection of males, in which sexual desire was accompanied by consistent caring behavior towards the female and her offspring. This attachment to a sexual partner may be evolutionarily linked to child-parent attachment (in some species, this connection is manifested in the features of sexual courtship rituals containing signs of childish behavior, which function to induce caring behavior and affection in a sexual partner). So according to this theory, the functional system of parental care and the functional system of mating became interconnected. Eibl-Eibesfeldt wrote that romantic love occurs through the fusion of parental care and sexual desire, and this fusion is an antecedent for children and adolescents to evoke romantic feelings in some adults (Eibl-Eibesfeldt, 1990 ).

In line with Eibl-Eibesfeldt, ethologist Herman Dienske argues that, in the course of evolution, due to the ability of human females to conceal ovulation and to be continuously sexually receptive, male sexual interest has evolved in turn to foster consistent male proximity (to invest in offspring that take so long to mature), and subsequently could promote male proximity with the infant (Dienske, 1990). Indeed, the repertoire of pedosexual behavior observed in humans, besides sexual actions, may also include caring behavior: comforting/caressing, feeding, grooming (body care such as washing or massage), protecting, teaching (Feierman, 1990).

Excerpts:

• Eibl-Eibesfeldt, Irenäus (1990). Dominance, Submission, and Love: Sexual Pathologies from the Perspective of Ethology. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 150–175). Springer, New York. doi:10.1007/978-1-4613-9682-6_6

  “If one observes courtship and greeting rituals in birds and mammals, one soon becomes aware that the patterns by which a friendly affiliation is established, upheld, or strengthened are basically derived from maternal behaviors and infantile appeals that trigger these patterns.”

  “In human sexual behavior, strata of different phylogenetic origins can be distinguished. Sexuality based upon the mechanisms of male dominance and female submission, which characterizes the reptiles, also constitutes the basic layer of human sexuality. This reptilian heritage is superimposed, however, by a more recently acquired sexuality characterized by affiliation and love. The new potentiality to act in a friendly manner evolved with the development of parental care independently in birds and in mammals. In normal human sexual behavior, the archaic agonal sexuality is controlled by affiliative sexuality and, therefore, is characterized by love. Agonal sexuality is still with us, however, as indicated, among other features, by the phallic male-dominance displays, by a male hormonal response linked to dominance achievement, and by the sexual fantasies of submission that are experienced by females. Agonal sexuality normally is under the control of affiliative sexuality, and therefore, humans correctly associate sex with love. Certain forms of sexuality, such as sadomasochism and a particular form of male homosexuality, are explained as being a regression to the archaic agonal sexuality. Pedophilia and pedosexual behavior are explained within the regression context, too. Children have characteristics, such as small size, that facilitate adult males' feeling dominant to them, as occurs in pedosexual behavior. Since human adult/adult romantic love is derived by phylogeny from parental caregiving behavior, it is easily seen how, in some adult humans, the feeling of love toward children has been retained and eroticized, which is the true meaning of the term "pedophilia.”

• Dienske, Herman (1990). The Concept of Function in the Behavioral Sciences with Specific Reference to Pedophilia and Pedosexual Behavior: A Biophilosophical Perspective. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 324–337). Springer, New York. doi:10.1007/978-1-4613-9682-6_13

  "it was pointed out that the continuous sexual activity of humans promotes the coherence of the adult-male/adult-female pair and that it encourages the male parent to participate in rearing his offspring. This assumption requires (1) that sex induces affiliation (i.e., the maintenance of proximity and the extension of favors) and (2) that this affiliation is continued after offspring are born and (3) is accompanied by male paternal care. The associations among sex, affiliation, and paternal care seem to be common in humans. This situation does not imply, however, a simple causal relationship. Infrequent or absent sex may precede divorce. It cannot be decided whether infrequent sex reduces affiliation or whether the decreased affiliation reduces sex. It is likely that sex and affiliation mutually enhance each other and that the absence of one of the two leads to a declining spiral that eventually results in separation or disinterest."

  “the associations among sex, affiliation, and paternal care are not compelling in that alternative functional solutions exist. Nevertheless, the affiliation-promoting effect of sex seems apparent.”

  “Human females, in contrast, lack such signals and thus have what is called "concealed ovulation" (Alexander and Noonan, 1979); in fact, the timing of human ovulation was not known until recently. Uncertainty concerning the time at which ovulation occurs would promote frequent copulations. It is possible that continuous sexual behavior in human females is their afflliation-promoting strategy, since it can induce more consistent male proximity (Daniels, 1983).”

  “[P]edophilic and homosexual nonprocreative sexual contacts could be considered functional, since favors resulting from the affiliation, which is maintained in part by sexual behavior, can be considerable.”

• Feierman, Jay R. (1990). A Biosocial Overview of Adult Human Sexual Behavior with Children and Adolescents. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 8–68). Springer, New York. doi:10.1007/978-1-4613-9682-6_2

  "some of the components of parental investment, collectively called "nurturing behavior", are seen in both pedo-and ephebophilia and can be considered and discussed as (1) comforting and contact, (2) feeding, (3) grooming, (4) protecting, and (5) teaching."

• Money, J. (1990). Pedophilia: A Specific Instance of New Phylism Theory as Applied to Paraphilic Lovemaps. In: Feierman, J.R. (eds) Pedophilia: Biosocial Dimensions. Springer, New York, NY. doi:10.1007/978-1-4613-9682-6_18

  "This author's way of circumventing the debate is to say that there are in the human species phylogenetic building blocks, or phylisms, that in the course of individual sexuoerotic development are capable of being diverted from their usual expression, so as to become entrained to sexuoerotic arousal. In the case of pedophilia, the phylism of parent/child pairbonding becomes diverted and entrained to sexuoerotic, lover /lover pairbonding. The pedophile's attachment to a child represents a merger of parental and erotic love."

  "The universal male/male pedophilia of the Sambia demonstrates the sexological plasticity of the human organism and the making of pedophilia into the social norm."

This hypothesis is also mentioned in modern scientific encyclopedias:

• Klapilová, K., Bártová, K. (2017). Sexual Pathology. In: Shackelford, T., Weekes-Shackelford, V. (eds) Encyclopedia of Evolutionary Psychological Science. (pp. 7439 - 7445). Springer, Cham. doi:10.1007/978-3-319-16999-6_3382-1

  “the evolutionary explanation behind the origin of pedophilia refers to the fusion of two evolutionarily ancient adaptive systems – reproduction and nurturing. Money (1990) states that a pedophile’s relationship to a child qualitatively, and also neurologically, resembles a blend between parental and erotic love. Likewise, it can be linked to the close cohesion between these two systems that can be observed also between phylogenetically close species.”.

  ”The founder of the human ethnology field, Irenäus Eibl-Eibesfeldt (1973), directly warns about the type of affiliative-erotic relationship that connects to the composition of long-term partnership, which was developed both in mammals and birds together with nurturing behavior, and therefore it is not surprising that they are occasionally mixed in humans.”

• Stevens, A., & Price, J. (2016). Evolutionary Psychiatry: A new beginning (Classic Ed.) (pp. 206-218) Routledge/Taylor & Francis Group. doi:10.4324/9781315740577

  “We would entertain the hypothesis proposed separately by Eibl-Eibesfeldt (1990) and by Money (1990) that two innate biosocial propensities – caregiving and sex-mating – have become fused in the course of ontogeny in those who display the paedophilic orientation.”

  “[A]ffiliative erotic love, as Eibl-Eibesfeldt points out, itself evolved in birds and mammals together with the development of parental care-giving behaviour. ‘Since human adult/adult romantic love is derived by phylogeny from parent care-giving behaviour,’ asserts EiblEibesfeldt, ‘it is easily seen how, in some adult humans, the feeling of love toward children has been retained and eroticised, which is the true meaning of the term “pedophilia”.“.

Complementary behavior among minors

The hypothesis of pedophilic attraction as a promoter of affection and care is confirmed by the existence of complementary behavior of minors, who often show initiative and willingness for sexual relations with adults. It’s assumed that such a behavior could function to receive affection and extra resources not available from the child's default caregiver. This testifies to the evolutionarily beneficial and reciprocal essence of intergenerational attraction (Klapilová & Bártová, 2017; Stevens & Price, 2016; Rind, 2013 ).

• Klapilová, K., Bártová, K. (2017). Sexual Pathology. In: Shackelford, T., Weekes-Shackelford, V. (eds) Encyclopedia of Evolutionary Psychological Science. (pp. 7439 - 7445). Springer, Cham. doi:10.1007/978-3-319-16999-6_3382-1

  “The child’s adaptive behavioral function to demand nurture from adults and his prospective urge to perform sexual activities is not mentioned too often. Still, it is a rather widespread behavior across cultures and historical periods that can help the child receive extra resources not available from their own parents. It would therefore be a complementary strategy – from the pedophile’s side, there is the eroticization of nurturing behavior and attraction to signalization that encourages caretaking, whereas from the child’s side, it is a functional, environmentally conditioned strategy that brings benefits in the form of resources and possibly even acquisition of sexual experience and calibration of child sexuality”.

• Stevens, A., & Price, J. (2016). Evolutionary Psychiatry: A new beginning (Classic Ed.) (pp. 206-218) Routledge/Taylor & Francis Group. doi:10.4324/9781315740577

  “it is undeniable that many children in our society – especially those in boarding schools and childrens’ homes – suffer from ‘parent hunger’. They are what Mia Kellmer-Pringle has called ‘touch-hungry children’. It is possible that the care-eliciting ‘phylism’ in these children may become eroticized just as the care-giving phylism may be eroticized in adult paedophiles. Thus, children starved of parental affection may compete for the love and attention of adults in their environment by using erotic solicitation as a strategy for survival. To suggest this possibility is not to excuse adults who exploit the emotional needs of children for their personal gratification but to provide an evolutionary explanation as to how and why erotic bonds between adults and juveniles may occur. We would propose that both care-eliciting and care-giving phylisms can be eroticized.”

Neurological, endocrinological and psychological evidence

Human sexuality researchers have confirmed the neurobiological interconnection of sexual and attachment systems. The release of oxytocin, vasopressin and prolactin, hormones associated with parental behavior, during sex and orgasm stimulates the formation of attachment, altruistic behavior and care for a partner. The reverse is also true: trusting and caring relationships can evoke sexual interest (Dewitte & Marieke, 2012 ; Fleischman, 2021 ).

Two decades after Eibl-Eibesfeldt suggested that the neural systems of sex and care are relatively more connected in people who are sexually attracted to children, neuroscientists have found some experimental evidence for that. Brain structures responsible for social connections, altruistic and parental motivation (such as the left anterior insula), in people with pedophilic interest, respond to infant stimuli more intensively, receiving reinforcement from the neural circuits responsible for mating. In addition, a greater connection between parental and mating systems is characteristic of males, which is explained by evolutionarily different ways of forming maternal and paternal investments (Ponseti et al., (2018). ).

Excerpts:

• Ponseti et al., (2018). "Decoding Pedophilia: Increased Anterior Insula Response to Infant Animal Pictures". Front Hum Neurosci.

  “This gives rise to the assumption that increased brain responses to infant stimuli in pedophilia are rather a consequence of an over-active nurturing system than of an over-active sexual system.”

  “The left anterior insula, being a crucial area of nurturing processing, was also frequently found to be activated in sexual brain studies (Stoleru et al., 2012). Furthermore, the left anterior insula (as well as the SMA) is a constituent of the human attachment system, thereby enabling both nurturing and pair-bonding (Feldman, 2016). Based on both observations, (i) the over-responding to nurturing stimuli in various motivational areas and (ii) the functional overlap of nurturing and sexual processing of the involved left anterior insula a tentative and simple model of pedophilia could be as follows: Nurturing stimuli receive additional processing resources by mating-circuits. In case of human infant stimuli this leads to a sexual connotation of infant stimuli. This idea is supported by the suggestion that nurturing and pair-bonding are two closely inter-related domains in humans at the level of physiological functions, brain processing, and involved neuropeptides”

  "In any case, from an evolutionary perspective, paternal nurturing is an unusual and probably more recently evolved male behavior. Phylogenetically speaking, male brains are not “geared” to handle infant stimuli. This may explain why the “parental caregiving” network of males and females displays differences (Abraham et al., 2014).

  It might be hypothesized that, in contrast to ancient maternal infant stimulus processing, human male brains process infant stimuli with brain areas that might not be associated primarily with caregiving. If so, it is conceivable that the involvement of brain areas not “geared” to the paternal nurturing aspects associated with infant stimuli makes male brains vulnerable to not maintaining the functional division between the domains of nurturing and mating behavior."

• Schuler, M. et al (2019). "Empathy in pedophilia and sexual offending against children: A multifaceted approach," Journal of Abnormal Psychology, 128(5), 453–464.

  "Participants included 85 pedophilic men who committed hands-on child sexual offenses (P+CSO), 72 pedophilic men who never committed hands-on child sexual offenses (P−CSO), and 128 nonoffending teleiophilic male controls (TC). Several affective and cognitive aspects of empathy were assessed using the Multifaceted Empathy Test (MET) and the Interpersonal Reactivity Index (IRI). Whereas in self-reports (IRI) P+CSO scored lower than TC (P−CSO intermediate) in cognitive perspective-taking abilities, a performance-based measure (MET) revealed evidence for a better differentiation of emotional states in P−CSO as compared with P+CSO (TC intermediate). In addition, P+CSO and P−CSO showed significantly higher affective resonance while observing children (MET), which was paralleled by higher self-reported levels of personal distress in social situations (IRI). The results indicate evidence for higher general affective empathic resonance to children in pedophilic men but superior cognitive empathy abilities in nonoffending pedophiles only, which may act as a protective factor in the prevention of sexual offending."

Sex and attachment in general

• Fletcher, G. J. O.; Simpson, J. A.; Campbell, L.; Overall, N. C. . (2015). Pair-Bonding, Romantic Love, and Evolution: The Curious Case of Homo sapiens. Perspectives on Psychological Science, 10(1), 20–36. doi:10.1177/1745691614561683

  "Factor analytic studies of perceptions of romantic love in Western samples support these models, typically revealing three components (e.g., Aron & Westbay, 1996). The labels assigned to each factor vary across studies, but they reflect passion (sexual attraction), emotional bonding (intimacy), and commitment (caregiving)."

  "romantic love provides a potent motivational push toward the kind of devotion and commitment required for the huge investment needed to support a mate and raise children successfully."

  "romantic love is an adaptation — a commitment device — that facilitated longterm pair-bonding"

  "The striking similarity between the behavioral manifestations of parent–infant love and romantic love suggests that evolution may have borrowed these ancient bonding mechanisms, originally evolved in mammals to bond mothers to their offspring, and applied them to men and women in the context of romantic pair-bonding."

  "Using phylogenetic comparative methods with 230 different species, Opie et al. (2013) found that the evolution of monogamy is strongly related to paternal care of offspring"

Evolutionary by-product of human neotenization

Another factor of pedosexual attraction emergence is a human neotenization. The evolutionary advantage of retaining neotenic (childish) traits which elicit nurturing responses from adults, results in the retention of neotenic genetic traits due to sexual competition. Therefore such traits become sexually attractive. That leads to the observable progressive neotenization of humans in comparison with ancestors and subsequently increases likelihood of juveniles being sexually attractive. Since fertile females retained juvenile traits into their fertile years, the line between fertile and infertile female age became blurred. Thus, some males become oriented toward females who are too young for reproduction (Feierman, 1990).

Excerpts:

• Feierman, Jay R. (1990). Human Erotic Age Orientation: A Conclusion. In: Jay R. Feierman (Ed.), Pedophilia: Biosocial Dimensions (pp. 552–566). Springer, New York. doi:10.1007/978-1-4613-9682-6_23

  “All of these genetically and culturally transmitted processes blur the distinction between reproductively competent adults and children and adolescents. Therefore, all of these processes must be considered to be determinants, at some level, of pedo- and ephebophilia.”

  “pedo-and ephebophiles, like chins and spandrels, may have no primary adaptive function in themselves but, instead, may be rank-ordered by-products of selection for more adaptive attributes in their kin.”

• Lievesley, R. and Harper, C.A. (2024) “The interaction between perceived chronological age and physical sexual development in attractiveness judgments made by people who are attracted to children”, Psychology and Sexuality, DOI:10.1080/19419899.2024.2321149

  "From an evolutionary perspective, men typically perceive more youthful faces as more attractive due to these indicating a greater degree of fertility (Gallup & Frederick, Citation2010, Little, Citation2015, Thornhill & Grammer, Citation1999). [...] [A]n increased degree of closeness of facial features appears to be encoded as indicating youth (Albert et al., Citation2007), and in turn, this youthfulness is associated with beauty (Sutherland et al., Citation2013)."

• Bogin, B. (1997). Evolutionary hypotheses for human childhood. Yearbook of Physical Anthropology, 40, 63–89.

  "Taken together, these studies indicate that adults are more likely to protect or nuture individuals with ‘‘neotenous’’ facial features. McCabe defines such features as having a relatively large ratio of cranium size to lower face size."

Mentorship-Bonding/Enculturation-Alliance Hypothesis

On the basis of previously available evolutionary explanations (Mackey, 1990 ; Muscarella, 2000 ; Kirkpatrick, 2000 ; Neil, 2009), Bruce Rind developed a hypothesis explaining the most widely documented type of male homosexuality in human history, namely pederasty (the relationship between a man and a peripubertal/adolescent boy) (Rind, 2013 ).

It is assumed that the evolutionary function of man-boy sexual relationships comes from our evolutionary past, when the environment was very different from the modern one. Humans have had a long evolutionary history as hunter-gatherers. This time was characterized by intergroup warfare and the hunting of large animals. To do this, it was necessary to form close-knit same-sex male groups, to form specific male skills of war and hunting, and to maintain the specific masculine culture of this group. This created a selection pressure to create a mechanism to facilitate such rallying, recruitment and enculturation of new members, which is a long-term and labor-intensive undertaking. It is hypothesized that the sexual attraction between a boy and a man became such a mechanism, through the ability to form a strong emotional connection, prompting the mentor to teach and care, and the boy to seek training and a role model.

The evolutionary benefit of such a mechanism is assumed both at the individual level (for the junior this is training, protection, and promotion in the male hierarchy, for the adult this is the expansion of the network of alliances) and at the group level (the clan received a reliable replenishment of group members, well-prepared, enculturated and committed to the culture of the group, which gave a competitive advantage).

This hypothesis is supported by cross-cultural studies, where a variety of independent cultures demonstrate the prevalence of sexual relations between men and boys of peripubertal age. These relationships are built into these cultures and are part of growing up and becoming a man. The readiness, desire and initiative for sexual contact comes not only from adult men, but also from boys, and this is recorded as a typical phenomenon in these cultures. This also confirms the existence of an evolutionary benefit for younger participants.

Moreover, this attraction is not associated with reproductive losses, unlike exclusive homosexuality. It is typical of all these cultures that, upon reaching adulthood, men get wives and at the same time have sexual relations with boys themselves. It is assumed that this ability of the average heterosexual male to experience pederastic attraction is specific to our species.

But this ability is optional (facultative). That is, unlike obligate heterosexual attraction, pederastic interest is to a large extent activated or suppressed by the social environment. This explains the fact that there is a sharp difference in the prevalence of pederastic behavior and attraction between cultures, and the fact that in modern Western cultures it does not manifest itself widely.

Excerpts:

• Rind, B. (2013). Pederasty: An Integration of Empirical, Historical, Sociological, Cross-Cultural, Cross-Species, and Evolutionary Evidence and Perspectives. In: Thomas K Hubbard, Beert Verstraete (Eds.), Censoring Sex Research: The Debate over Male Intergenerational Relations. (pp. 1-90) New York: Routledge. doi:10.4324/9781315432458

  “Formally, this hypothesis holds that pederasty evolved in the early human hunter-gatherer EEA [Environment of Evolutionary Adaptedness] as an adaptation (i.e., exaptation), whose function it was to reproduce the male group by facilitating the mentoring and enculturation of boys from peripubescence through adolescence, as well as their emotional and psychological binding with the group. This function was a solution to the recurring adaptive problems in the EEA of surviving and exploiting an extremely dangerous and competitive social and physical environment”

  “In short, the ages of boys sought out as recruits in male groups, the period in which they are mentored and enculturated, the ages of boys that men in such societies (and our own) find erotically appealing, the ages at which boys are especially open to being mentored (and capable as well, owing to an emergent adult-cognitive capacity), and the ages at which they are open to pederastic relations appear to be part of a single package, in which each of these characteristics seems to be a design feature and element of a larger design, whose function is reproducing the male group.”

  “It is important to emphasize that pederasty’s relatively infrequent expression in societies such as ours does not imply that it is not an adaptation. In our society, developmental inputs have traditionally been intensely hostile toward homosexual behavior, often accompanied by severe social sanctions, including public disgrace and punishment, which can be expected to have had a significant dampening effect on the emergence and activation of pederastic desire and the expression of pederastic behavior.”

  “Thus, even though adaptive in the EEA , pederasty, being a facultative trait, is nevertheless rare in our environment. On the other hand, in cultures with cultural ideologies and social structures facilitative of pederastic desire and expression, its occurrence has been widespread across the male population, which is consistent with the assumptions that most males have at least a moderate potential for the behavior and that such potential is sufficient for the behavior to emerge, provided other factors are not inhibitory.”

• Schiefenhövel, W. (1990). Ritualized Adult-Male/Adolescent-Male Sexual Behavior in Melanesia: An Anthropological and Ethological Perspective. In: Feierman, J.R. (eds) Pedophilia. Springer, New York, NY. doi:10.1007/978-1-4613-9682-6_16

  "Men are expected to plan, work, fight, and sometimes, die together. The necessary altruistic behavior and effective cooperation of the warriors as well as the acceptance of a male hierarchy would have been fostered by the institution of prescribed homosexuality."

• Riegel, D. L. (2011). The role of androphilia in the psychosexual development of boys. International Journal of Sexual Health, 23(1), 2–13. doi:10.1080/19317611.2010.509696

  "Proceeding from Feierman's (1990) thesis, it can be postulated that in prehistoric times it is likely that many children, due to violence, disease, poor nutrition, and life spans that were considerably shorter than what we have considered normal for the past couple of centuries, found themselves without either parents or other adults who would be willing to take on the burden of looking after and feeding a not yet productive child. However, a boy who was sexually androphilic (Vanggaard, 1969) would have the potential advantage of closely bonding with an older male whose sexuality included a male-directed pedosexual component, and who would preferentially protect, provide for, and teach the boy the skills necessary to survive and prosper. Studies have identified such secondary boy-attracted pedosexual tendencies in 20% to 30% of self-identified heterosexual adult males (Freund, 1970; cf. Briere & Runtz, 1989, Quinsey, 1984, West, 1980), and these tendencies would not be selected against so long as the bearers were primarily heterosexual and only secondarily male-oriented pedosexual. There is no reason to believe that these percentages were not similar in prehistoric times; there is some evidence for familial transmission (Gaffney, Lurie, & Berlin, 1984). In the absence of our modern-day taboos, such adaptive and beneficial boy/older male relationships could proceed unimpeded, the boy's juvenile androphilic sexuality would typically be supplanted by heterosexuality as he matured (Sandfort, 1987), he would then pass on his genes, and thus both of these traits would be maintained in the gene pool."

• Rind, Bruce. (2014). Trends in evolutionary explanations for human male same-sex eroticism: a commentary on Riegel (2011). International Journal of Sexual Health, (), 1–11. doi:10.1080/19317611.2014.956853

  "In this commentary, I discuss his social critique and focus on his evolutionary hypothesis, reviewing seven earlier hypotheses for comparison. "

  "Werner (2006) focused exclusively on the evolution of male homosexual behavior. Based on selected cross-species data, he posited that male homosexual behavior evolved in stages over eons of time. In the first, involving primitive species (e.g., reptiles), single adult males controlled territories, where they waited for females for mating. Adolescent or transvestite males, who resembled adult females in form and/or behavior, gained entry to these territories because of their female mimicry and they were tolerated once there because they submitted homosexually to the adult resident. Their benefit for this submission was mating opportunities with visiting females, which otherwise would not have been available to them. In the second stage, male homosexual behavior changed function (i.e., was an exaptation) in various more complex descendent species with greater cognitive capacities (so that deception via female mimicry no longer worked) and in which adult males lived together in groups rather than as isolates. Here, the changed function of homosexual submission was to elicit tolerance from the dominant male, which served to uphold the dominance hierarchy, which in turn facilitated multi-male group living. The third and final phase occurred when multiple males did not simply live together but cooperated on common tasks. Here, male homosexual behavior changed function once again, in which it facilitated alliance formation, which in turn enabled pursuit of common tasks. He called his explanation the hierarchy/cooperation theory for human male homosexual behavior. Werner claimed that pathic (i.e., transgenderal) homosexuality was the most common form of male homosexual behavior cross-culturally, followed by transgenerational homosexuality. He speculated that different social structures produce different strategies for male/male cooperation, which in turn determine the form by which male homoeroticism is expressed."

Childhood as a target for sexual selection

Some authors have suggested that not only adolescence but also middle childhood are involved in sexual selection process, and evolved as a stage at which individuals not only could but should take responsibilities. This appears to contradict how childhood is constructed in modern society (see also research on childhood competence). According to such theories, in middle childhood, individuals become "nest helpers", helping in nurturing for younger siblings, foraging, and chores. This is a fine tuning stage of later social and sexual life-history strategies. First sexual or romantic attractions, sexual play, separation in gender roles typically emerge several years before puberty reflecting the fact that children are drawn into the evolutionary process of sexual selection much earlier than they become fertile. At this stage they actively learn sociosexual behavior and receive feedback about their sociosexual success from peer and adults, adapting their sexual competitive strategy to the environmental input. They engage in sexual and romantic relationship along with adults benefiting from learning, resources and social status they gain. This contributes to their sexual success in later life stages.

• Del Giudice M. (2014) Middle childhood: an evolutionary-developmental synthesis.; 8:193–200. doi:10.1111/cdep.12084. in: Halfon N, Forrest CB, Lerner RM, et al., editors. Handbook of Life Course Health Development. Cham (CH): Springer; 2018. doi: 10.1007/978-3-319-47143-3

  "In summary, the life stage of juvenility/middle childhood has two major interlocking functions: social learning and social integration in a system of roles, norms, activities, and shared knowledge. While children are still receiving sustained investment from parents and other relatives—in the form of food, protection, knowledge, and so forth—they also start to actively contribute to their family economy. By providing resources and sharing the burden of child care, juveniles can boost their parents’ reproductive potential. The dual nature of juveniles as both receivers and providers explains many psychological features of middle childhood and has likely played a major role in the evolution of human life history (Kramer, 2011)."

  "Middle childhood is one of the main stages of human development, marked by the eruption of the first permanent molars around age 6 and the onset of androgen secretion by the adrenal glands at about 6-8 years (Bogin, 1997)."

  "The transition to middle childhood is typically associated with a strong separation in gender roles, even in societies where tasks are not rigidly assigned by sex."

  "The stress response system plays a major role in gathering and storing information about environmental safety, predictability, and availability of resources; adrenarche contributes by translating that information into adaptive, sexually differentiated patterns of behavior (Del Giudice et al., 2011; Ellis & Del Giudice, 2014). Consistent with this view, both early relational stress and early nutrition have been found to modulate the timing of adrenarche (Ellis & Essex, 2007; Hochberg, 2008). It is no coincidence that the first sexual and romantic attractions typically develop in middle childhood, in tandem with the intensification of sexual play (Bancroft, 2003; Herdt & McClintock, 2000). By interacting with peers and adults, juveniles receive feedback about the effectiveness of their nascent behavioral strategies. The information collected during middle childhood feeds into the next developmental switch point, that of gonadarche (Ellis, 2013)"

  "By determining children’s initial place in social networks and hierarchies, competition in middle childhood indirectly affects their ability to attract sexual and romantic partners later. In other words, middle childhood is a likely target for sexual selection — that is, natural selection arising from the processes of choosing mates (mate choice) and competing for mates (mating competition). My colleagues and I (Del Giudice et al., 2009) argued that sexual selection is one reason why sex differences emerge and intensify in middle childhood."

Other relevant information

Ontogenetic plasticity

Here's an explanation for why, if a minor attraction was adaptive, it may not be ubiquitous today.

• Alanko K, Salo B, Mokros A, Santtila P, (2013). "Evidence for heritability of adult men's sexual interest in youth under age 16 from a population-based extended twin design." J Sex Med, 10(4):1090-9.

  "Adult men's sexual interest in youthfulness‐related cues may be genetically influenced. [...] The amount of variance attributable to nonadditive genetic influences (heritability) was estimated at 14.6%.[...] Compared with the variance attributable to nonshared environmental effects (plus measurement error), the contribution of any genetic factors seems comparatively weak."

  Editor: Note, that a heritability coefficient close to zero does not mean the weakness/absence of genetic control over the trait, counter wise may point to high genetic consistency among population, in which case the trait variance is naturally more dependent on the environment. ("Traits such as walking and breathing have low heritability, because these are usually universal traits with slight variations. [...] as heredity becomes more similar, the environment becomes the primary explanation for differences.") This finding of low heritability may be interpreted to mean that the genetic ability to develop minor attraction is highly pervasive among humans and modified by nurture and other environments. This goes along with the Rind's conclusion on pederasty as evolutionary determined but a facultative trait.

• Bhugra, D. (2000). Disturbances in objects of desire: Cross-cultural issues. Sexual and Relationship Therapy, 15(1), 67–78. doi:10.1080/14681990050001574

  "Paraphilias are defined as sexual attractions to objects or individuals not normally found attractive. [...] It is argued that, in some types of individual deviance, cultural factors are more likely to play an important role. Some cultures are seen as sex-positive and others as sex-negative but, within each cultural setting, attitudes towards sex and the function of sexual activity are a key to understanding the development of sexual deviance. In cultures where sex is seen as an attraction-led phenomenon rather than a purely procreative one, individuals are more likely to be attracted to 'objects'."

Undesirable traits as adaptations

Both pedohebephilic attraction and childhood sexuality are likely influenced somewhat by environmental factors. For example, there exist theories of adverse childhood in pedohebephiles and factors of earlier sexual development in youth sexuality. These are unproven and causality is hard to infer. It has been speculated that these are complementary adaptations to difficult circumstances.

From a layman's point of view, undesirable traits that arise as a result of adverse environment are mental breakdowns. From an evolutionary perspective, these may be ways to adapt in a harsh, primordial context. It is worth keeping this perspective in mind.

• Belsky, J., Steinberg, L., & Draper, P. (1991). Childhood experience, interpersonal development, and reproductive strategy: An evolutionary theory of socialization. Child Development, 62, 647–670.

  "The concept of "reproductive strategy" drawn from the field of behavioral ecology is applied to the study of childhood experience and interpersonal development in order to develop an evolutionary theory of socialization. The theory is presented in terms of 2 divergent development pathways considered to promote reproductive success in the contexts in which they have arisen. One is characterized, in childhood, by a stressful rearing environment and the development of insecure attachments to parents and subsequent behavior problems; in adolescence by early pubertal development and precocious sexuality; and, in adulthood, by unstable pair bonds and limited investment in child rearing, whereas the other is characterized by the opposite."

• Del Giudice, M. (2014b). Early stress and human behavioral development: Emerging evolutionary perspectives. Journal of Developmental Origins of Health and Disease, 5, 270-280.

  “Stress experienced early in life exerts a powerful, lasting influence on development. Converging empirical findings show that stressful experiences become deeply embedded in the child's neurobiology, with an astonishing range of long-term effects on cognition, emotion, and behavior. In contrast with the prevailing view that such effects are the maladaptive outcomes of 'toxic' stress, adaptive models regard them as manifestations of evolved developmental plasticity.”

  “Building on the concept of developmental plasticity, researchers have been increasingly advancing alternative models in which early stress does not primarily impair or dysregulate children’s developmental trajectories, but rather shifts them toward behavioral strategies that have proven biologically adaptive in harsh or unpredictable conditions”

  “Exposure to stress works as a cue to local environmental conditions, and feeds into plasticity mechanisms that coordinate the development of alternative phenotypes.”

  “In this perspective, many putative maladaptive traits such as anxiety, aggression, and impulsivity can be reframed as costly but adaptive phenotypes that improve an individual’s survival and reproduction prospects in hostile, unpredictable contexts. For example, increased vigilance and anxiety can be regarded as defensive reactions to potential threats, whereas aggression and impulsivity can be effective competitive strategies in harsh, unstable social environments. Furthermore, there is evidence that high levels of physiological and emotional reactivity increase an individual’s sensitivity to context, making him/her more open to both negative and positive social influences. Of course, some of these adaptive traits are going to have undesirable consequences for the individual and/or the social group, and may even be diagnosed as symptoms of psychopathology (e.g., conduct disorders). According to adaptive models, children exposed to early stress should exhibit patterns of impaired cognitive and emotional functioning when tested in safe, stress-free contexts and/or with tasks that mimic the demands of those contexts; but they should often perform better than their peers on tasks that reproduce key features of the dangerous, unpredictable environments they are adapted to. The initial evidence suggests that this may be the case.“

Response to critique of evolutionary explanations

• Karen Franklin. (2010). Why the Rush to Create Dubious New Sexual Disorders?. , 39(4), 819–820. doi:10.1007/s10508-010-9616-1

  "As all students of Darwin know, evolutionary success strategies must be understood on a population-wide basis, not an individual level. Moreover, social scientists generally agree that biological evolution is rarely sufficient to understand human behavior in modern, complex social systems. Thus, to say that a trait may have emerged as evolutionarily adaptive in prehistoric times implies nothing of its presence or function on an individual level in contemporary society."

See also

• Debate Guide: Evolutionary logic
• Intergenerational Relationships in History
• Intergenerational Sexual Behaviors in Animals