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The evolution of male homosexuality: implications for human psychological and cultural variations.

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Abstract

Evolutionary explanations must do two things. 1) explain where the trait derived from (phylogeny), and 2) how the trait survived and reproduced (how the genes that determined or permitted the trait could continue). This essay looks at data to argue that human male homosexuality evolved gradually with social complexity from 1. markings of territory, 2) markings of domination/submission, 3) markings of alliances, 4) human homosexuality. The adaptive question is how EXCLUSIVE homosexuality could be passed on. The argument suggested here is that cooperation requires a combination of genes for propensity to dominate and submit (not necessarily just one gene locus with two alleles). Individuals with too much dominance would die in battles before being able to reproduce. Those with too much submissiveness would not even try to reproduce. So only those with mixed genes would pass on their DNA. By the rules of Mendelian genetics, every generation would produce individuals with different degrees of dominance and submissiveness. It is the most submissive males who constitute the exclusive "passive" homosexuals. This theory helps account for the many forms homosexuality takes across cultures, including homosexual sex between socially undifferentiated men (as in war and prison rapes, catamite systems, master-apprentice systems), homosexual relations between undifferentiated males and socially differentiated passives (transvestites, etc.) and between socially differentiated and other socially differentiated males ("gay" system)
FROM:
Werner, Dennis. 2006 The evolution of male homosexuality and its implications
for human psychological and cultural variations, Chapter 13. IN Volker
Sommer and Paul L. Vasey (eds.) Homosexual Behaviour in Animals.
Cambridge: Cambridge University press. pgs.316-346.
The Evolution of Male Homosexuality and its
Implications for Human Psychological and
Cultural Variations.
Dennis Werner
Antropologia, Universidade Federal de Santa Catarina, Florianópolis, SC, BRAZIL
ABSTRACT
Comparisons of different primate species suggest that male homosexuality evolved along with male
cooperation which passed through distinct stages of 1) marking territories, 2) marking submissive
males via mechanisms previously used for territorial markings, 3) marking alliances via mutual
gestures of dominance and submission. Among humans, exclusive male homosexuals are at the
extreme submissive end of a dominant/submissive personality continuum. Individuals at the two
extremes of this continuum do not reproduce ― extreme dominants because they die in fights, and
extreme submissives because they do not attempt reproduction. However, due to the random way
genes are combined, the extremes of the continuum continue to appear.
The “hierarchy/cooperation” theory helps explain certain aspects of human homosexuality, and
clarifies the debate between “essentialists” and “constructivists.” People in all human cultures share
with other primates certain cognitive and behavioral markers of dominance and submission. Also
there may be common differences between “pathics” (exclusive homosexuals) and typical males in
all cultures. Finally, recent studies of bisexuality from non-European cultures clarify how the
hierarchy/cooperation theory helps explain why cultures vary so widely in behaviors and definitions
of homosexuality.
KEY WORDS: homosexuality and culture, dominance hierarchies, primate sexuality, evolution of
sexuality, bisexuality
EVOLUTIONARY THEORIES FOR MALE HOMOSEXUALITY
In the past few decades, evolutionary psychology has demonstrated its value in accounting for
human behaviors and inspiring new ideas to be tested. An evolutionary view of male homosexuality
may also contribute to many current debates regarding the nature (and culture) of human
homosexuality. As with all evolutionary theories, there are at least two questions that must be
answered. First, we must explain how homosexual orientations could survive and/or reproduce in
light of selection pressures. This is the question of adaptation. Second, any evolutionary
explanation must also clarify how a given trait could have arisen. No matter how adaptive a trait
may be, it must have a traceable past. This is the question of phylogeny. I will examine separately
each of these questions.
Adaptation and Male Homosexuality
There are at least three different levels at which homosexuality may be seen as adaptive, and each
of these levels has its own implications with regard to how homosexuality manages to continue
among humans. At the most abstract level, homosexuality might be unrelated to genetic
differences or to universal genetic programs that regulate ontogeny. Instead, homosexuality may
be culturally determined in a manner far removed from direct genetic influences. Following
Dawkins' (1976), we might call this the "memic" level. At a less "abstract" level, we might assume
that homosexuals and heterosexuals have the same genes, but that during ontogeny universal
genetically determined "programs" get "switched on" or "switched off" depending on environmental
influences. Thus, people may have the same genotypes, but these genotypes may produce
different phenotypes in different situations. This might be called the "epigenetic" level. Many
theories (including Freudian ideas) about the psychological dynamics behind homosexuality are of
this type. Finally, at the most concrete level, we might posit genetic differences between
homosexuals and heterosexuals. I'll call this the "genetic" level. Many biological studies seem to
support this view.
Evolutionary arguments have been offered for all of these levels. For example, Symons (1979)
argues that homosexuality results from a meme that takes advantage of the inborn male propensity
to find sexual variety interesting. Normally this propensity would be adaptive because it would
encourage males to attempt sexual relations with many women, which would result in more
offspring. But a meme could parasitize this propensity, redirecting sexual interest to non-adaptive
objects, as in fetishism or homosexuality. Epigenetic arguments have been inspired by work on pre-
natal hormones. Dörner and his colleagues (Dörner et al. 1980; LeVay 1994) link stress during
pregnancy to hormonal effects on the fetus that would lead to homosexuality. This could be part of
a mother's adaptive reproductive strategy. That is, in times of stress, when it is difficult to raise
children, it may be adaptive to have some homosexual children who could help their siblings raise
offspring instead of having offspring of their own. Finally, studies of gene linkages have pointed to
genetic differences between male homosexuals and heterosexuals (Hamer et al. 1993; Mustanski et
al. 2005). Various evolutionary theories have been proposed to account for genetic arguments.
Whether genes lead directly to homosexuality or whether they simply program for homosexuality
under certain environmental conditions, they would still undercut reproduction. Thus, the basic
question for genetic and epigenetic arguments is to account for how such genes could survive the
pressures of natural selection. Several hypotheses have been proposed. First, a maladaptive gene
might re-occur repeatedly in a population if it results from the frequent mutation of a gene that is
normally adaptive. However, people with maladaptive genes rarely exceed 1% of the population,
while male homosexuality apparently occurs much more frequently (Whitam and Mathy 1986;
Gadpaille 1980; Diamond 1993). Another possibility is that genes that lead to homosexuality might
have hidden advantages. For example, homosexuals could directly help their relatives (who share
the “homosexual” genes) raise more children. Nevertheless, cross-cultural research shows that,
although male homosexuality is somewhat more common in patrilocal societies, it is not more
common in societies with endogamy or extended families where homosexuals live closest to their
relatives and so could presumably most help them (Werner 1979).
A second theory argues that a gene that is especially advantageous for females might inadvertently
cause homosexuality in males. According to this argument, the female relatives of male
homosexuals should be especially successful in their reproduction. I know of no empirical studies
for this hypothesis.
A third theory argues that genes “for homosexuality” might be maladaptive by themselves, but
might be advantageous when combined with other genes. This latter scenario is sometimes known
as the "heterozygous" “hybrid vigor” or “heterosis” hypothesis (LeVay 1994; Sommer 1990). What,
then, might be the advantage of homosexual genes when combined with heterosexual genes?
Kirsch and Rodman (cited in Sommer 1990) suggest that this advantage may have something to do
with dominance hierarchies. The maintenance of these hierarchies presumably helps animals,
including humans, live peacefully together, and this peaceful living provides advantages to the
group, and to the individuals in the group. The heterosis argument suggests that homosexuality
results from genes for submissive behavior. But the key to the argument is the disadvantage of an
animal that has only dominance genes. While an animal possessing only submissive genes would
fail to reproduce for lack of trying, one possessing only dominance genes might also fail. After all,
an animal that "fights and runs away, lives to fight another day," but an animal that never gives in
often dies young. In this light, consider Chagnon's (1988) discovery that Yanomami men who had
killed more enemies had more offspring than milder men. Chagnon used this correlation to argue
that aggressivity really does enhance reproductive success. But Chagnon's study suffers from a
sampling problem ― It included only living males. Very possibly the more aggressive males also
had a greater probability of dying before ever being able to reproduce at all! Thus, on average,
milder men may have as many or more offspring than aggressive men.
According to the heterosis argument it is the males with a mixture of dominant and submissive
genes, who would most likely reproduce. By genetic laws, this would leave every generation with a
certain percentage of individuals at the extremes. For example, if each of a pair of chromosomes
had only one "homosexual" locus with only two possible alleles (one for dominance and one for
submissiveness) this would leave a heterozygous couple with 25% of their offspring homozygous
for submissiveness, 50% heterozygous, and 25% homozygous for dominance. If, however,
homosexuality were the result of the interaction of many genes, possibly spread across different
chromosomes, then fewer individuals would have only submissive genes. Of course there are many
possible genetic scenarios for this argument. Indeed, different genes may affect different aspects of
homosexuality, as new research is beginning to suggest (Mustanski et al. 2005).
The heterosis argument still needs to be tested. It predicts, for example, that the relatives of
exclusive homosexuals should have less dominant personalities than the general population, in
addition to predicting that homosexuals themselves would be more likely than heterosexuals to
avoid fights (at least physical ones), for which there is already abundant evidence (Whitam and
Mathey 1986; Cardoso 2004).
Phylogeny and Male Homosexuality
Many evolutionists (Gould 1977b; Rieppel 1992; Reichholf 1992; Antinucci 1990) have complained
about the emphasis placed by sociobiologists on natural selection to the detriment of questions of
phylogeny. According to these authors, sociobiologists have an overly "atomistic" approach to
evolution, acting as if specific biological traits can evolve all by themselves, without regard to
structural constraints on design or to the possibility that given changes may or may not be possible
in phylogenetic history. Tracing phylogeny is important because natural selection does not operate
like an engineer, drawing up a blueprint, and then constructing a machine from scratch in the most
efficient way possible. Rather, natural selection operates more like a "tinkerer" taking advantage of
materials already available to produce new forms that "work" at the moment. Elsewhere (Werner
1999b) I argued that adaptational arguments (like functional arguments in general) are more
common in the Anglo-Saxon academic world, while phylogenetic arguments (like structural
arguments in general) are more common among continental academics. A more balanced
perspective is in order.
The heterosis theory of homosexuality proposes that genes that affect submissiveness also affect
homosexuality. This suggests that the key to understanding homosexuality may lie in the evolution
of submissive behavior. We are unlikely to find many clues in the fossil record, but a search for
homosexual analogues and homologues in other animals may be informative. Sexual relations
between males can be found even in very simple species. In his review of animal homosexuality,
Sommer (1990) mentions the case of "homosexual rape" in a parasitic worm (
Moniliformis dubius
).
In this case, the raped male's genital opening is blocked off with a spermless semen plug donated
by the rapist. The raped male cannot then fertilize females. A variation on this theme is the
homosexual rape of the bedbug
Xylocaris maculipennis
. In this case, instead of blocking up the rival
male's genital opening, the raping male inserts his own sperm into the rival male's semen ducts.
This also occurs with fresh water snails of the genus
Biomphalaria
, which are vectors for
schistosomiasis (Forsyth 1991). When the raped male copulates with a female, he fertilizes her with
his rival's sperm.
Very different is the "homosexual" behavior found in the ten-spined stickleback fish. During
spawning activities the male must court a female in order to get her to lay her eggs. Sometimes a
second female is invited into the courting arena, and then the male may succeed in fertilizing the
eggs of two females. But sometimes the second "female" is really a transvestite subordinate male,
who, because of his disguise, succeeds in entering the rival's arena and fertilizing himself the
female's eggs, or he may simply eat the already fertilized eggs (Sommer 1990). A variation on this
theme is found in the bluegill sunfish. In this species there are three different types of males. First
is the larger "parental" male, who defends a nest or courting arena. Second, is the much smaller
"sneaker" who sometimes succeeds in darting into a parental's courting arena and fertilizing the
female's eggs before the larger male perceives him. Third are the "transvestites" who resemble
female bluegill sunfish, and manage to get invited into the arena (Wilson 1994). As they grow, the
"sneakers" gradually turn into "transvestites," but the "parental" males are genetically different.
That "transvestite" behavior may also be structurally related to homosexual activities is shown in
the case of the lizard
Anolis garmani
. In this animal the main perceived difference between males
and females is size. Small males are usually driven out of the territories of larger males, but much
smaller males are sometimes confused with females. On entering a more dominant male's territory,
these small males behave like females and let themselves serve as sexual partners to the larger
males. This trick not only gives the subordinates access to the dominant's territory and to his
females, but also succeeds in making the dominant male "waste" his sperm. A similar ploy is used
in forest salamanders ― subordinates succeed in tricking dominant males into giving up their sperm
packets (Sommer 1990), and by male Manitoba garter snakes (
Thamnophis sirtalis parietalis
) that
give off female scents that attract other males into giving up their sperm.
Some of these examples of "homosexuality" in phylogenetically distant animals may be analogous
rather than homologous to human homosexuality, but as we move closer to humans the likelihood
of homologous behaviors increases. In mammals many different behaviors have been observed that
might be associated with male homosexuality. Among primates homosexual behaviors are
particularly diverse. These include such practices as the mounting of one male by another (e.g.
langurs, pig-tailed macaques, baboons, orangutans, chimpanzees, bonobos) (Sommer 1990; Oi
1990; Lorenz 1963; Yamagiwa 1992; Hayaki et al. 1989), including mounting with anal penetration
(e.g. stump-tailed macaques, squirrel monkeys) (Sommer 1990; Maple 1977), and mounting with
anal penetration and ejaculation (Japanese macaques, rhesus macaques, gorillas) (Sommer 1990;
Gadpaille 1980; Edwards and Todd 1991; Bagemihl 1999). Masturbation of other males has also
been reported, including mutual masturbation (e.g. stump-tailed macaques) (Sommer 1990) as well
as genital-genital contacts (e.g. bonobos) (Enomoto 1990), at times leading to ejaculation (e.g.
gibbons) (Edwards and Todd 1991). Fellatio has also been reported for stump-tailed macaques
(Sommer 1990). Other perhaps related behaviors include sniffing/inspecting the genitals/anal
region of other males (e.g. stump tailed macaques,) (Sommer 1990), "displaying" an erect penis to
other males (e.g. vervet macaques)(Henzi 1985), and urinating a few drops on the other male
during the display (e.g. squirrel monkey)(Castell 1969). In some cases males have shown a
preference for their homosexual partners over heterosexual partners (e.g. rhesus macaques)
(Sommer 1990).
These behaviors have been reported for a diversity of situations ― most notably in displays of
dominance and submission, in cases of general excitation, and in more playful situations among
adolescent males and between adult males who demonstrate special affective relationships with
each other.
At first glance the relationships between the different behaviors and the situations in which they
occur seem arbitrary. For example, in some cases it is the dominant or older male who mounts the
younger or subordinate (e.g. observations among gorillas) (Yamagiwa 1992), in other cases it is the
reverse (e.g. pig-tailed macaque) (Oi 1990). Presenting the anal region to another animal may
indicate one's dominance (e.g. squirrel monkey) (Ploog et al. 1963), or it may be a submissive
gesture (e.g. baboon) (Lorenz 1963). It may be the dominant who sniffs/licks the subordinate
adolescent's genitals (e.g. howler monkeys) (Young 1983), or the subordinate who sniffs/licks the
dominant (e.g. Hapalidae) (Epple 1967). It may be the dominant who ejaculates (e.g. squirrel
monkey) (Ploog et al. 1963) or the subordinate adolescent (e.g. gibbons) (Edwards and Todd
1991). In some cases it is the dominant individual who urinates (e.g. squirrel monkey) (Castell
1969). In some cases the reverse (e.g. a subordinate wolf may urinate on itself)(Lorenz 1963).
The different sexual activities and their social associations seem so diverse that it is tempting to
conclude that more complex animals have simply evolved a "flexible" sexuality that allows them
arbitrarily to find virtually anything sexy. Indeed, phenomena like the occasional sexual imprinting
on different species or even on objects would seem to confirm this view (Maple 1977; Lorenz
1963). In light of this diversity Bagemihl (1999, p. 261-262) simply eschews all attempts at
explanation, and prefers instead to exalt in a “biological exuberance” which “embraces paradox,”
and “is about the unspeakable inexplicability of earth’s mysteries.” Still, I think it possible and
profitable to search for order behind this chaos. We just need to look a little more closely at the
situations in which these behaviors occur.
I propose that male homosexuality evolved through various stages. The most primitive stage occurs
in animals without multi-male groupings, and where males are generally intolerant of the presence
of any other adult male. In this stage, homosexuality is basically a deception tactic to gain access
to others' territories (although the animals may not know they are practicing deception or being
deceived). This is the stage of the "transvestite" lizards and snakes described above. Possibly such
transvestite behavior may be a pre-condition for the use of sexual "mounting" to express
dominance in more complex animals. The connection may have something to do with how males
succeed in imitating females. Lorenz (1963) gives the example of
Cichlid
fish. Males recognize
females only by the fact that females can mix the emotions of fear and sexual excitement while
males cannot. He argues that many vertebrates distinguish between the sexes only by the different
ways males and females mix basic emotions. Allowing oneself to be sexually mounted is then
associated with submission.
A more complex stage of homosexuality occurs where multi-male groups are adaptive, perhaps in
avoiding victimization from predators or for other reasons, but where males do not cooperate with
each other on specific tasks. In this situation, more powerful males may have reasons to expulse
other males, but they also have an incentive for allowing them to stay. The "solution" to this
dilemma is the maintenance of a clear dominance hierarchy. The subordinates may stay in the
group, but must periodically "pay homage" to the dominant to clarify their provisional "guest"
status. The rituals used to define this dominance may derive from various sources. One source is
the behavior used to mark off territories. Many animals have scent glands (often near the genital-
anal region) that take advantage of urine or feces secretions to deposit scents on a territory's
borders or elsewhere. When subordinate males are allowed to stay near a dominant male, part of
the price may be having these territorial markers literally "rubbed in their faces". For example,
Epple (1967) describes the genital displays (perhaps best described as "mooning") among dominant
males in different
Callitrichidae
species. In
M.a.argentatus
the dominant male, with a threatening
face, shows his anal-genital region to a subordinate, who crawls to him with gestures of anguish,
while emitting submissive sounds, and then smells the dominant's genitals. When extremely fearful,
submissive males may smell only the dominant's tail. Sometimes the dominant male backs into the
submissive and rubs his genitals in the submissive's fur, thus marking the subordinate directly with
his own markers. Often the dominant withdraws his testicles, but shows an erection during these
displays. The dominant's erection may serve to clarify that he is allowed to have an erection (and
sexual relations with females), and the subordinate must get used to seeing this. The subordinate
is not permitted this license.
Squirrel monkeys have similar, but somewhat more complex dominance rituals. The dominant male
approaches a subordinate, opens his thighs (sometimes while touching the subordinate with his
hands and/or penis) and "displays" his erect penis in the subordinate's face, sometimes emitting a
few spurts of urine in the process. The subordinate usually hunches over and may succeed in
turning his face away from the display, but if he does not remain sufficiently passive or tries to
move away, the dominant may become enraged and aggressive (Castell 1969; Ploog et al. 1963).
The relationship between these displays and sexuality involves more than just the fact that erect
penises are being displayed. Among mouse lemurs, for example, exposure to the urine of an active
dominant male reduces the testosterone level of adult males (Stoddart 1990), which plausibly may
reduce their sexual activities ― Male prairie voles, exposed to male urine, delay their sexual
maturation (Forsyth 1991). At least for the squirrel monkey, there is clear evidence that the
subordinate animals engage in less sexual activity (Ploog et al. 1963).
In its genital displays, the squirrel monkey is very similar to the
Callitrichidae
. But the squirrel
monkey has a more complex repertoire. In addition to genital displays, dominants also demonstrate
their status by mounting submissives, including anal penetration. Possibly, an ancestral
"transvestite deception" system combined with a "scent-marking" system to produce the squirrel
monkeys' dominance rituals. Or perhaps the ancestral shows of erect penises simply become more
explicit. In any case, the squirrel monkey's dominance system also has other novelties. Dominant
males sometimes "ask" other males to stay. They do this by rolling on their backs and exposing
their bellies, sometimes showing an erect penis. Animals that would normally run away stay around
if the dominant performs this ritual. This makes for a slightly more cohesive male group than occurs
among the
Callitrichidae
.
A particularly dramatic variant of the genital display is found in vervets (Henzi 1985). Vervets have
bright red penises with powder blue scrota. During submissive gestures, males retract both their
penises and their scrota into their bodies, while the dominants leave both extended. In one display,
the dominant walks or runs toward the submissive and then turns perpendicular to him so the
submissive can observe the dominants' genitals, which the submissive always does. In another, the
dominant circles around the submissive showing his anal/genital region, sometimes holding on to
the submissive during the display. In addition to these non-solicited displays, the submissives
sometimes seek out the dominants in order to "pay homage" to them. They do this by submissively
running after them, or creeping up to them, and at times cupping the dominant's testicles in their
hands and tugging. Both dominants and submissives have been observed with erections during
these latter rituals. Other multi-male species also show "homage-paying" behavior. Lorenz (1963)
describes an incident in which a defeated baboon chased after his conqueror "presenting" his
behind until the dominant finally mounted him. This may help explain why, among white-handed
gibbons, an adolescent was observed soliciting sexual contact with the adult male in his family
group. As Edwards and Todd (1991) suggest, the youth may have needed “reassurance” that he
was still welcome in the family.
I think the different rituals of the
Callitrichidae
versus the squirrels, and vervets reflect different
levels of male/male cooperation. Compared to the
Callitrichidae
example, the observations among
the other two species seem to have been of clearer, more stable hierarchies. Among the vervets
the dominants were confident enough that they could leave their testicles descended during the
displays while the
Callitrichidae
brought them out of harm's way. Squirrel monkeys have been
observed inviting fearful subordinates to stay around, and allowing them to show erections which
suggests more value given to maintaining the multi-male groups.
The stability or instability of dominance positions may help explain some of the apparently
"contradictory" rituals reported by ethologists. For example, among pig-tailed macaques
submissives have been observed mounting the dominants more than the reverse (although it is the
dominant who solicits this behavior). Yet immediately after a new monkey rises to the top, it
refuses to let others mount it. This may be because this is an especially unstable moment when
doubts about hierarchical positions need to be affirmed (Oi 1990). Dominants, when secure in their
positions, may profit by “ceding” to submissives at times.
In many of these primates immature males seem to "practice" these dominance rituals, displaying
or presenting to each other and allowing their partners to mount them (e.g. vervets, rhesus,
gorillas, orangutans). This youthful play may be the beginning of what in even more socially
complex species becomes an affective type of adult homosexuality, in which neither partner is
dominant to the other. "Neoteny" is a common way for "new" traits to appear in a species (Gould
1977a). Adult bonobos, for example, often cement alliances with homosexual activities (Waal
1989).
By way of conclusion, there are a few important points to be made about primate homosexuality.
The first is that, in most cases, the homosexual behavior has a pacifying effect ― averting
aggression, reassuring subordinates of their place, or cementing alliances ― although a forced
homosexual display may also represent a challenge during a hierarchical dispute. Also, the
different forms of homosexuality seem to "scale", that is, the behaviors and associations found in
the simplest species are also found, under certain circumstances, in the more complex animals. But
the more complex animals have some additional complications not present in the others. If this
scaling is correct, then this suggests that homosexuality is closely tied to the evolution of more
complex social behavior ― probably due to its effect in reducing hostilities between males.
Although some authors (e.g. Kirsch and Rodman ― cited in Sommer 1990) emphasize only
dominance hierarchies in the origins of proto-homosexual behaviors, these hierarchies should
probably be seen as only one act in a longer play that begins with territoriality and deceptive
"transvestite" tactics and ends with alliance formation and affection. This is a play about how
animals came to cooperate with each other, and about the origin of society. I can see no reason for
not adding an encore for human homosexuality. Humans are certainly much more cooperative than
other animals, and our society is much more complex. What does all of this imply, then, about
human homosexuality?
IMPLICATIONS OF THE HIERARCHY/COOPERATION THEORY FOR
HUMAN HOMOSEXUALITY
Before seeking evidence for the hierarchy/cooperation theory among humans, it is necessary to
clarify questions surrounding one of the major academic debates of the last two decades the
“essentialists vs. constructivists” (See Cardoso and Werner 2004 for a brief historical review of this
debate.) “Essentialists” postulate more universal biological and psychological bases for
homosexuality, while “constructivists” see “homosexuality” as having no meaning whatsoever
outside of its cultural context. Supporting an “essentialist” viewpoint, most biologists cite evidence
for genetic and epigenetic causes of homosexuality, while psychologists point to the common
childhood precursors, and common personality and cognitive traits of homosexuals. To support a
“constructivist” view anthropologists and social historians cite the great variation across human
cultures in the ways homosexuality is organized or defined. A brief summary of the evidence for
these views may help clarify the debate.
“Essentialists”: Biologists and Psychologists
Biological studies have documented differences between male homosexuals and
heterosexuals in their exposure to prenatal hormones (Levay 1994; Reinisch et al. 1991), brain
structures (LeVay 1994; Swaab and Hoffman 1990), genetic markers (Hamer et al. 1993; Mustanski
et al. 2005), and possibly other characteristics such as fingerprint patterns (see Downtown 1995
with regard to a University of Western Ontario study), that may be related to testosterone exposure
(Jamison, et al. 1993). In addition, effeminate boys (who have a strong tendency to become adult
homosexuals) are judged more attractive than other boys (Zucker, et al. 1993) which agrees with
Green's (1987) finding that parents of effeminate boys rated these as more "beautiful" babies than
their other children.
Blanchard & Sheridan (1992) found that homosexual men had more older siblings than
nonhomosexual men, and other studies found homosexual males had more older brothers than
heterosexual males (Blanchard 2004; Blanchard & Klassen 1997; Cardoso 2004), possibly reflecting
a progressive immunization of some mothers to H-Y histocompatibility antigen. Other researchers
(Dörner et al. 1980; Cardoso 2004) found that the mothers of male homosexuals may have
suffered more maternal stress during pregnancy.
Finally, support for genetic arguments has come from studies of twins and of homosexuality in
family histories (Whitam 1983; Bailey and Pillard 1991; Buhrich et al. 1991; Eckert et al. 1993;
Pillard and Weinrich 1986; Flores 1994; Cardoso 2004). Anecdotal evidence from tribal level
societies also suggests inheritability of homosexuality ― Wilbert (1972, p. 101) reported that the
Warao Indians of Venezuela think that transvestites are more common in some of their families
than in others.
The most complete and careful study of family relationships and homosexuality is Green's (1987)
fifteen-year comparison of effeminate and masculine boys beginning from the time the boys were
four to twelve years old, and continuing into adulthood. The boys and parents were interviewed
and observed regularly over this time period, and psychological tests were administered at various
points. Of 30 feminine boys accompanied throughout this period and with sexual experiences, 24
were "more than incidentally homosexual" as adults. Of the 25 "masculine" controls, only 1 was
more than incidentally homosexual as an adult. Many of the effeminate boys were subjected to
behaviorist or other therapies during their childhood, all apparently without effect on their later
homosexual behaviors or fantasies. In addition, although a good deal of attention has been given
to the role of parental child-rearing behavior, neither Green nor others (Greenstein 1966;
Siegelman 1974; Green 1987) found much support for these arguments.
However, childhood gender non-conformity consistently predicts adult homosexual orientations in
North America and Europe, as well as other cultures (Phillips and Over 1992; Cardoso 1994; Green
1987; Whitam and Mathy 1986; Whitam and Zent 1984). While homosexuals are more likely to
have been effeminate as boys, there are still many homosexual males who have reported more
normal childhoods (Phillips and Over 1992). Weinrich and his colleagues (cited in LeVay 1994)
showed that it is the homosexuals who prefer a more "passive" role (as "insertee") who are most
likely to have been effeminate boys. These findings have led researchers like Green to propose
causal models for homosexuality that begin with the influences of genes and pre-natal hormones.
Characteristics of parents (like the desire for a girl or a boy) might affect acceptance or tolerance of
feminine behavior in boys, which in turn might affect their adult femininity, but have less effect on
their homosexuality.
“Constructivists”: Anthropologists and Historians
Most anthropologists and historians feel frustrated with the biological and psychological work on
male homosexuality because it seems to account so poorly for the cross-cultural variation in male-
male sexual relations. This variation is so great that it seems impossible even to define
homosexuality in a cross-culturally meaningful way. To find causes that are cross-culturally valid
seems preposterous. For example, Dickemann (1993) cites the case of homosexuality in medieval
Europe. She argues that during the period of Charlemagne parents simply decided that their last-
born son should adopt homosexuality, and apparently the parental decisions were followed. When
we consider the even more "exotic" cultures of New Guinea (Herdt 1993; Kelly 1974), the
arbitrariness of cultural definitions of homosexuality seems even clearer. In societies like the
Sambia or Etoro, all boys are expected to have sexual relations with older males. Indeed, people
believe that the boys' maturation would be impossible if they did not receive semen from the older
males. Among the Etoro sexual relations between men and women are taboo most days of the
year, although homosexual relations are constantly encouraged.
Compatibility of the essentialist and constructivist views
If there is no such thing as "homosexuality" in a cross-culturally meaningful sense, then what
should we make of the biological findings? I think there are two possibilities. First, the biological
findings may be peculiarly Western. That is, there may be no gene for "homosexuality," but rather
genes for other characteristics that our particular culture associates with "homosexuality." For
example, parents may define certain inborn facial features as "beautiful" in their babies. This may
lead them to treat these babies as more delicate and "feminine" than other babies. It is the later
"femininity" of these boys which then gets defined as "homosexual."
I think a more likely possibility is that the cultural differences are not really so great. The apparent
incompatibility between the biological and cultural arguments may simply be a question of their
dealing with different phenomena. Biologists are more interested in sexual orientation ― what
sexually attracts individuals or is behind their fantasies. On the other hand, anthropologists are
more interested in sexual practices ― that is, who has sex with whom, and what people actually do
in these sexual relations. Anthropologists are also extremely interested in sexual identity ― how
cultures define individuals, and how individuals see themselves. In both practices and identity there
is certainly a great deal of cultural variation. But we know much less about the cross-cultural
variation in orientation as defined here. The differences among these concepts are not always clear
in the works of different scholars. For example, Herdt (1993 p. xlvii) states that "Identity includes
feelings, ideas, goals and sense of self." Money and Ehrhardt (1972) often speak of sexual
"identity" without distinguishing this from "orientation" and without considering the influence of
culture in forming these identities.
Evolutionary psychologists tend to emphasize what is universal to all cultures, while cultural
anthropologists generally concentrate on what is unique. To resolve the discrepancies between
“essentialists” and “constructivists,” I think the most productive approach is to examine those
cultural features that are common to
some
cultures but not to others. One typology, originally
suggested almost 40 years ago (Gorer, 1966), groups cultures into one of three male homosexual
systems “gender-stratified systems,” “age-stratified systems,” and “egalitarian systems.”
By far the most common homosexual system in the ethnographic record is the “gender-stratified
system” in which typical males may engage in active (inserter) sexual relations with distinctly
identified “pathics” who generally assume passive (insertee) roles. The pathic (often a transvestite)
might take on an honored religious role as among the South African Zulu or the Patagonian
Tehuelche, or he may be mistreated as among the Angolan Mbundo, or the Bolivian Chiriguana,
although his active partner receives no rebuke. He might eventually assume the role of a second or
third wife of a typical male, as among the Warao of Venezuela, the Tanala of Madagascar, the
Karen of Burma, or the Chukchee of Siberia, or he might serve various men in the community
throughout his lifetime as among the Brazilian Tupinamba. Just how often typical men in these
societies participate together in sexual escapades with the pathics is unknown, but judging from a
few ethnographic reports and drawings of the “dance to the berdache,” such “partying” may not be
rare (Katz 1976; Werner 1999a). Murray (2000) coded 120 societies as “gendered-stratified.”
“Age-stratified” homosexual systems include “mentorship” or “ritualized homosexuality” systems, in
which an older male takes on a younger male as an “apprentice,” as well as “catamite” systems in
which younger males serve simply as sexual objects to a powerful, older male. “Mentorship”
systems have been found among groups as diverse as the ancient Greeks, Australian Aborigines,
numerous New Guinea cultures, Tibetan monks, Japanese samurais, Egyptian Siwans, and the
Zairean Azande. They are remarkably similar in many respects. Boys may begin their
initiation/apprenticeship as young as 7 years as among the New Guinean Sambia, or as old as 12
among the Azande, and may continue their apprenticeship until as old as 20 or 25 as among the
New Guinean Etoro. After this age, young men generally switch to more active roles with younger
boys. It is very common for a father to choose carefully his son’s tutor, and in most, if not all cases,
the relationship between the two is monogamous, and involves instruction in practical matters as
well as moral courage and discipline (Werner 1999a). “Catamite” systems were quite common in
the Hellenistic empire as well as other societies, such as ancient Rome, China, Korea, Japan, Egypt,
Turkey and the African Ashanti. Among the West African Mossi, chiefs had sex with boys on Fridays
when sex with women was taboo. In some cases the boys were simply kept as slaves, while in
other cases they traveled with theatrical troupes and served as prostitutes as well. Murray (2000)
coded 53 societies as “age-stratified.”
“Egalitarian” homosexual systems include societies a) where homosexual relations occur among
typical males only during adolescence, b) where “blood-brotherhoods” may formalize homosexual
ties between typical males throughout life, and c) where homosexually identified males have sex
primarily with other homosexually identified males (the modern “gay” system). “Egalitarian”
systems are relatively rare in the anthropological record. Murray (2000) coded only 30 societies as
“egalitarian.” And “gay” systems may be limited to Northern Europeans and their descendants of
the past few centuries, which is probably what most social constructivists (e.g. Foucault 1978) are
talking about when they refer to the recent cultural construction of “homosexuality.” Still, it is the
“gay” system which most non-anthropologists have in mind when they talk about homosexuality.
The “gay” system seems to be gaining ground in many countries of the world. For example, Murray
and Arboleda (1995) noted changes over time from “gender-stratified” to “gay” systems in
Guatemala, Mexico, and Peru. In the 1970s, only 50% of their informants had heard of the term
“gay,” and only 23% thought it referred to both “passive” and “active” partners. In the 1980s, 76%
had heard of the term and 58% applied it to both “passives” and “actives.” Cardoso’s (2004) data
from Thailand, Turkey and Brazil showed that the “gender-stratified” system is most common
among the lower classes in each of these cultures, while the professional classes generally adhere
to the “gay” system1.
Most societies can be classified as adopting one or the other of these homosexual systems, but
different sectors of a culture may adhere to different systems, and at times even the same sector
may recognize different systems. For example the ancient Greeks had “mentorship” systems of
homosexuality, but also recognized pathics with distinct terms, and prohibited them from holding
public office (Murray 2000). The Australian Murngin also recognized pathics as distinct from other
males, although a “mentorship” form of homosexuality also characterized their society. In addition,
homosexual behavior may also occur at other moments within a society such as among prisoners,
in street gangs, or to humiliate enemies in warfare (Duerr 1993).
It is important to recognize that most of the cultural variation in homosexuality refers to the
homosexual behavior of typical males, not to the sexual orientations or even social identities of
homosexually identified males. Thus, it is entirely possible for researchers to acknowledge the
cultural “construction” of homosexual behaviors among typical males, while still recognizing that
homosexuals (pathics) share “essential” traits in all known human societies.
Implications for humans of the hierarchy/cooperation theory
What kinds of evidence might support or refute the "hierarchy/cooperation" argument for
homosexuality? There are three questions for which evidence may be forthcoming. First, the theory
makes predictions about deeply rooted feelings in all humans. Second it may account for individual
variation in all cultures. Third, it may help explain why cultures vary.
Universals
If the association between cooperation and homosexuality is correct, then we should expect
humans to show more homosexuality than most other complex animals, with the possible exception
of bonobos, who, as Wrangham and Peterson (1996) argue, may be even more cooperative and
more homosexual. I think humans do practice more homosexuality, although an over-concentration
on North European cultures and an over-concentration on genital-sex may sometimes confuse the
issue.
The review of animal homosexuality suggests that more complex animals add new complexities to
the already existing repertoires of simpler species, yet they still retain the older repertoires. We
should, thus, find evidence of these older repertoires in humans. This makes sense in terms of the
"tinkerish" economy of natural selection. As modern neuroscientists have pointed out (Damasio
1994; LeDoux 1996), the human brain is constructed in "layers." The phylogenetically inner layers
are more conservative, varying less from one species to the next, in conformity with the great
dictum of natural selection: "If it ain't broke, don't fix it". The outer layers are more recent, and
vary more from one species to the next and from one individual to the next (Cairns-Smith 1996).
Thoughts or perceptions organized in the outer layers need to produce their effects by acting
through the inner layers. For example we may reason our way (using the outer brain layers) into a
fearful state (produced in the inner layers), or may similarly reason our way out of a fearful state.
However, when the different regions of the brain are in disagreement, feelings may be less
"convincing" (Damasio 1994; LeDoux 1996). When they all agree, they may be perceived as
especially powerful or "raw."
The differences are seen even in language. As etymologies show, our abstract concepts are almost
always constructed from analogies with more concrete phenomena, and children learn concrete
concepts long before they are able to make abstractions. Swear words are especially concrete.
Unlike other language capacities, swearing has its origins in the phylogenetically older sub-cortical
parts of the brain. Brain-damaged individuals may lose their capacity for virtually all language, but
still retain the ability to swear (Pinker 1994). Psychoanalysts (e.g. Arango 1989) and
anthropologists (Duerr 1993) have taken advantage of this phenomenon to analyze the sources of
our most powerful emotions. In the case of dominant/submissive relations our swearing vocabulary
is rich and revealing. Primate mounting behavior is revealed in expressions like "he wants your
ass," or "up yours!" References to submissive individuals in different languages are consistently
related to primate gestures of submission. In English we call overly submissive individuals "ass
kissers" or "brownies." In German and Vietnamese, the expressions are only slightly different:
"
Arschkrieche
r," and "
NimBa
," respectively, expressing the act of crawling up to the dominant's
behind. Spanish speakers say "
lame culo
," southern Slavs "
Dupolizac
", and Russians "
Podliza
" all
referring to licking the dominant's behind. The Brazilian term,
puxa-saco
(scrotum tugger), refers
to another primate gesture, while Turks use "
Kiçimi yala
" referring to ass licking although they also
possess the milder "
Dalkavuk
," referring simply to the subordinate's bowed back. Uruguayans say
chupa
medias
” (literally ‘sock sucker”), referring to what may be another scent marker. Other
English expressions based on primate-gestures include "rubbing it in", "smearing it in your face",
and "sucker." The reader can probably fill in more examples, including some only slightly more
abstract expressions.2
Individual Differences
"Dirty words" are helpful in understanding attitudes that may be deeply rooted in all individuals. But
in all cultures there may be important differences between people as well. Most anthropological
studies have concentrated on general cultural norms, categories, and symbolic systems, not on
individual differences. This is unfortunate, because it tells us little about individual variation in
homosexual activities for these societies. Often it is difficult enough just to affirm that exclusive
homosexuals are absent. For example, Werner (1984) describes a traditional myth about a
transvestite among Brazil’s Kayapó Indians, but the Indians reported having never heard of a case.
On the other hand, Crocker (1990) reports the presence of transvestites among the Kanela Indians
of Brazil, but suggests the culture had no tradition of transvestites. One wonders whether cultures
simply adapt to transvestites or homosexuals in their midst when they happen to appear.
Anecdotal accounts of pathics in many tribal societies suggest similar childhood backgrounds to
Western homosexuals, but more systematic data are extremely rare. Still, statistical studies in a few
more complex non-Western societies have confirmed U.S./European findings with regard to the
correlations between exclusive homosexuality on the one hand and childhood behaviors or family
histories on the other (Whitam 1983; Cardoso 2004).
Even rarer are studies of the psychological and social differences between typical men who do or
do not have occasional homosexual relations. Such studies are uncommon even for the U.S. These
studies may be particularly revealing with regard to the evolutionary theory postulated in this
paper. For example, McConaghy and Blaszcynski (1991) looked at homosexual feelings among
males with predominant heterosexual attractions, and discovered that homosexual feelings are
most correlated with having disliked outdoor and contact sports. There were no correlations of
homosexual feelings with activities like cooking or playing with dolls as a child. Likewise, in his
study of 41 men from a Brazilian fishing community Cardoso (1994. 2002, 2005) found that the
men most interested in sex with the community's exclusive homosexuals were significantly more
likely to have avoided playing soccer as children than were other men who had fewer relationships
with the homosexuals. But these men were not different from other men in cross-gender behaviors
(like playing with dolls). These findings suggest that submissiveness may be more central to
homosexual feelings among typical males than is femininity.
Further clarification of the characteristics of “bisexuals” in different cultures comes from a larger
study in which Cardoso (2004) gathered interview and questionnaire data from 880 men between
the ages of 20 and 30 in cities in Brazil, Turkey and Thailand. Cardoso chose these societies in
order to maximize diversity, including a predominantly Christian, Muslim and Buddhist culture. His
sample was stratified to include homosexual, bisexual and heterosexual men from both working
and professional classes in each country. Comparisons of “bisexuals” (men who had sex with both
males and females) with exclusive heterosexuals was revealing. Bisexuals were intermediate
between heterosexuals and bisexuals on some childhood precursors of homosexuality (like not
playing soccer, preferring girl’s tasks, playing with girls, or wanting to be a girl), but they were
much closer to the heterosexuals than to the homosexuals on these variables. Perhaps more telling,
they rated higher than both homosexuals and heterosexuals in “liking to dominate” their sex
partner, and “receiving sexual invitations from women.” Some of the class distinctions help clarify
the meaning of these results. Compared to professional-class bisexuals, the working-class bisexuals
were less likely to have preferred girls’ tasks, or have wanted to be a girl, and they were actually
more likely than working-class heterosexuals to have bullied others when young (Cardoso 2004).
Very likely there are two quite distinct profiles of “bisexuals” in the working classes. In Cardoso’s
sample of working class bisexuals, those who liked to bully also liked to dominate their sex partner
(r=.50, p<.001), but they were not more likely to have “girlish” childhoods (all correlations with
bullying were negative, although not statistically significant). On the other hand, those who showed
one “girlish” childhood precursor also tended to have the other girlish precursors (correlations
between .21 and .48, all significant) (Cardoso, personal communication). It is perhaps the presence
of a non-intermediate type of “bisexual” among the working classes that explains the apparently
greater frequency of homosexual behaviors found in his haphazard samples of typical working class
males.
These cross-cultural studies suggest a few factors that might be behind the cultural variations in
homosexual behaviors reported by anthropologists. To what extent, are cultural variations in line
with the hierarchy/cooperation theory?
Cultural Variation
The “hierarchy/cooperation” theory suggests that variations in the ways men cooperate or form
hierarchies might explain much of the cultural variation in male homosexual systems. What is the
evidence?
Elsewhere, Cardoso and Werner (2004) reviewed the results of statistical cross-cultural studies on
homosexuality. Of particular interest were the results of Murray’s (2000) and Crapo’s (1995)
comparisons of “gender-stratified,” “age-stratified,” and “egalitarian” systems of homosexuality. In
a nutshell, these studies showed that “egalitarian” systems are most common where males are
more involved with infant care, and where there is a generally more egalitarian social structure.
“Gender-stratified” systems are most common where males and females do similar tasks, where
women have more power, and where there is no adolescent segregation of the sexes. “Age-
stratified” systems occur where there is more patrilocality and patrilineality and greater segregation
of the sexes. This suggests that cultural variations in homosexuality may reflect different strategies
for male/male cooperation. Where men must invest more in children they eschew homosexual
relations, limiting homosexuality to adolescence, to rare “blood-brotherhood” ties or to “gays.”
Where they have more time to invest in cooperation they may engage in more homosexual
behavior, perhaps to better cement relations. If the society is sexually segregated, this takes the
“mentorship” form of homosexuality. Otherwise the “gender-stratified” system permits sexual
escapades with pathics.
Historical changes in how hierarchies are constructed may also help account for the origin of the
modern “gay” system in which typical males do not engage in homosexuality. Where hierarchies
are based on personal connections, loyalties between males may be encouraged, but with greater
professionalism, these ties may be disparaged as “nepotism” or “favoritism.” Cardoso’s (2004)
study supports this view. Lower class males in all three of his societies were more likely than
professional class males to agree that “getting ahead depends more on
whom
you know than on
what
you know.” More importantly, within the lower classes of all three societies, the bisexuals
agreed more with this statement than did the exclusive heterosexuals. These findings suggest that
the increasing importance of professionalism as societies become more industrialized may be
behind the expansion of the “gay” system at the expense of traditional “gender-stratified” systems
throughout the world.
The type of hierarchy in which men spend their lives may also affect the type of homosexual
behavior men perform. For example, where men are more preoccupied about their position in a
dominance hierarchy, the distinctions between what the submissives do and what the dominants do
should be accented. Indeed, in his study of prison rape Silva (1998) showed that, despite their
verbal “justification” of prison rape “to protect women and families” against convicted rapists, it
was actually those prisoners most preoccupied about their personal status who advocated raping
fellow prisoners.
As suggested by the pigtail macaque example cited above, concern about one’s place in a
dominance hierarchy may be most important where hierarchies are unstable or unclear. To
examine this idea Mendes (1997) carried out a series of experiments in which she asked male
university students to complete a short comic strip story about a prison. Mendes varied the stories
slightly to ascertain the effects of these variations on student responses. Stories that included
"intimate visits with women" significantly reduced the likelihood of ending stories with a
homosexual rape scene. But even with these visits, 40% of the subjects still ended their stories
with rape (other choices were physical fight, non-sexual friendship, and friendly sex). When Mendes
contrasted prisons organized on the basis of personal loyalties, versus an abstract evaluation
system, there was a slight (non-significant) tendency to cite rape more often in the "personal
loyalties" situation (53.3% versus 33.3% of 60 students). The statistically most significant
differences, however, occurred when Mendes combined the "personal loyalties" condition with
either "stable" or "unstable hierarchies" (few or frequent changes of cellmates). Where hierarchies
were more unstable, respondents were much more likely to end their stories with a rape scene
(68.5% versus 26.7% of respondents).
These findings suggest it may be useful to include questions of hierarchy/cooperation in general
studies of homosexuality. This may help explain a few apparently “anomalous” findings reported in
the literature. For example, consider the finding of Adams, et al. (1996) that homophobic men are
more sexually excited by homosexual pornography than are non-homophobes. The standard
psychoanalytic interpretation is that homophobia results from repressed homosexual desires. But
another possibility is that having an unstable status based on personal loyalties causes both greater
homosexual excitement and more concern about what role one plays in these relationships ― with
the passive role being denigrated. This might explain Cardoso’s (2004) findings that many bisexuals
are not intermediate between gays and straights, but rather more “masculine” when it comes to
liking to bully or dominate. Many other relationships between forms of male/male
cooperation/hierarchy and homosexuality might be hypothesized. But I hope these examples are
sufficient to show the value of an evolutionary perspective in suggesting what kinds of relationships
to look for.
BIOLOGICAL ADAPTATION, PSYCHOLOGICAL ADJUSTMENT, AND
MORALITY
The ideas I have been discussing here have been around for many years, but they have been
neglected, perhaps in part because many find them politically distasteful. I think this attitude
results from misunderstandings about the relationships between biological adaptation, psychological
adjustment and morality. In short, many people seem to have confused these really unrelated
concepts. Gadpaille (1980:354), for example, argues that "homosexuality as a preferential or
obligatory mode must by definition be biologically deviant," and implies that preferential
homosexuality is pathological. Similarly, the psychoanalyst, Arango (1989), in proposing a close tie
between dominance hierarchies and homosexuality, argues that homosexuality is not "love" but
"masochism."
But let us be clear here. Biological adaptation is not the same as "psychological adaptation" or
"psychological adjustment." Biological adaptation refers to the passing on of genes. It is genes that
are passed on, and that are adaptive or not. Individuals are never passed on ― they always die.
The heterosis argument has often been presented as the "sickle-cell" argument, in analogy with the
well-known case of sickle-cell anemia. In malaria areas, individuals homozygous for the sickle-cell
die of sickle-cell anemia, and individuals homozygous for the absence of sickle-cell are more likely
to die of malaria ― so mostly heterozygous individuals pass on genes. Now, in the case of sickle-
cell anemia we really are talking about an illness! No one wants to get sickle-cell anemia, and
people die from it. "Illness" and "health" are defined in terms of individual well-being, and perhaps
at times (e.g. psychopathic killers) in terms of social well-being. People do not need to pass on
genes to be considered healthy. They need to feel healthy and happy, and to not cause harm to
others. Certainly homosexuality should be considered "healthy." Arango's argument that
homosexuality is "masochism" is also off the mark, because it makes it sound as if our "real" selves
are what we find in the innermost regions of the brain. But human nature is based on our whole
brains. And of course all the different forms of human "love" (not just homosexual love) have their
evolutionary history. I doubt very much whether Arango would reduce these forms of love to their
homologues in ancestral fish!
Biological adaptation also tells us nothing about whether something is moral or not. Many adaptive
traits are evil for example the killing of another male’s offspring when a new male overtakes a
former dominant. Sommer (1990) has very nicely shown the absurdity of using the criteria of
"natural" (adaptive) or "unnatural" (maladaptive) to decide whether homosexuality is "good'" or
"bad." He found historical examples of scholars who argued for all the different possibilities: 1) that
homosexuality is natural (found in animals), therefore it is good, 2) that homosexuality is natural,
therefore it is bad, 3) that homosexual is unnatural, therefore it is good, and 4) that homosexuality
is unnatural therefore it is bad.
Still, there may be a tie between the notion of morality we actually have (not necessarily what we
ought to
have) and homosexuality. In short, surrendering one's own interests to the well-being of
another is what we mean by morality. Humans are capable of such surrendering because in their
evolutionary past they learned to yield at times rather than aggressively defend their own interests.
If the hierarchy/cooperation argument is right, then the evolution of morality depended on the
evolution of homosexuality. This may sound bizarre. If homosexuality is at the base of morality,
why are exclusive male homosexuals so defiled in so many places? I think the answer is simply that
they are easy to mistreat ― they generally yield more easily than others.
This contradiction between what we define as moral, and how we treat those who most comply,
may well be one of the major conflicts in human society. It deserves a name at least as catchy as
the Oedipus complex, although it is not an individual psychological complex, but rather a social
complex. If it is really as important as my argument suggests, then I imagined this complex must
appear in human myths. There are several possibilities. For example, the Kayapó Indians have a
story about a boy who shunned men's work, and was sexually abused by a bat man, which caused
him to giggle― the very first laugh ever, unworthy of a warrior, but necessary for life (Werner
1984). Among the Cashinuaha there is a story about a great transvestite artist who showed the
Indians how to draw, but who died because he was impregnated by a lover, and the baby could not
be born (Lagrou 1996). But the best-fitting story is closer to home. The story of Jesus is about a
man who "turned the other cheek" instead of fighting, who did not compete with other men for
women, and who, in the end, was easily mistreated. Perhaps someday humans will learn to
recognize this "Jesus Complex" and things will change, Then maybe Jesus' prophecy will be born
out: "Blessed are the meek, for they shall inherit the earth."
NOTES
1The differences between the North American/North European criteria and Brazilian lower-class
criteria were most dramatically clarified for me in observing Brazilian reactions to American
pornographic films. At one point in an American film a woman inserted her finger into her male
partner's anus. The Brazilian audience went wild, crying out "
viado
" (queer) to refer to the male
actor. On the other hand, in Brazilian
porno-chanchada
films of the 70’s it was not uncommon for a
man to have (active-role) sexual relationships with several women, and also with a
bicha
(effeminate homosexual). No one referred to the inserter male as
viado
in these film sequences.
2The use of more abstract “symbolic” expressions for dominance may be found in primates as well.
Enomoto (1990) reports the case of one male bonobo expressing its dominance over another by
using a gesture normally used to solicit sex from an estrous female.
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... Further, self-similarity preferences might be speci c to modern Western societies with the prevailing "gay" system, where both partners identify as homosexuals or gays and are of similar sociodemographic characteristics. In other historical periods and/or other populations, this picture can be profoundly di erent, mostly characterized by gender-strati ed or age-strati ed same-sex relationships, where one partner is signi cantly more masculine or older than the other, respectively (Hames et al., 2017;Murray, 2000;Werner, 2006;Whitam, 1983;Whitam & Mathy, 1986). Interestingly, in the sexual role (top vs. ...
... This preference seems to be more universal, and in some populations the sexual role determines whether the individual is identi ed as homosexual (or a "third gender"), or not (e.g., Cardoso, 2005). The sexually, gender-or age-strati ed partnering systems are suggested to re ect hierarchy between the partners and hierarchical structures of the given society (e.g., Werner, 2006). ...
Chapter
Evolutionary social science is having a renaissance. This volume showcases the empirical and theoretical advancements produced by the evolutionary study of romantic relationships. The editors assembled an international collection of contributors to trace how evolved psychological mechanisms shape strategic computation and behavior across the life span of a romantic partnership. Each chapter provides an overview of historic and contemporary research on the psychological mechanisms and processes underlying the initiation, maintenance, and dissolution of romantic relationships. Contributors discuss popular and cutting-edge methods for data analysis and theory development, critically analyze the state of evolutionary relationship science, and provide discerning recommendations for future research. The handbook integrates a broad range of topics (e.g., partner preference and selection, competition and conflict, jealousy and mate guarding, parenting, partner loss and divorce, and post-relationship affiliation) that are discussed alongside major sources of strategic variation in mating behavior, such as sex and gender diversity, developmental life history, neuroendocrine processes, technological advancement, and culture. Its content promises to enrich students’ and established researchers’ views on the current state of the discipline and should challenge a diverse cross-section of relationship scholars and clinicians to incorporate evolutionary theorizing into their professional work.
... Further, self-similarity preferences might be specific to modern Western societies with the prevailing 'gay' system, where both partners identify as homosexuals 20 or gays, and are of similar sociodemographic characteristics. In other historical periods and/or other populations, this picture can be profoundly different, mostly characterized by gender stratified or age stratified same-sex relationships, where one partner is significantly more masculine or older than the other, respectively (Hames, Garfield, & Garfield, 2017;Murray, 2000;Werner, 2006;Whitam, 1983;Whitam & Mathy, 1986). ...
... Cardoso, 2005). The sexually, gender or age stratified partnering systems are suggested to reflect hierarchy between the partners, and hierarchical structures of the given society (e.g., Werner, 2006). ...
Preprint
Human sexual orientation is an intriguing phenomenon which is still poorly understood and has important evolutionary implications. Evolutionary based studies mostly focus on heterosexual individuals and relationships, probably because non-heterosexuality concerns a minority of the population and decreases individual direct reproductive success. To better understand human nature, it is important to analyse whether the mating psychology of minorities exhibit specific evolved sexual/reproductive strategies. Here we review studies on partner preferences, mate choice, and flirting in non-heterosexual populations, to identify which patterns are similar to or different from heterosexuals. The general pattern supports the notion that sex differences are larger than within sex variation among people of different sexual orientations. However, although some mating strategies among non-heterosexuals resemble heterosexuals of the same sex, others resemble heterosexuals of the opposite sex, and yet in others, the pattern is different than among either heterosexual men or women. We point to limitations of the current state of this research, and we suggest possible future directions in the study of non-heterosexual relationship initiation.
... Further, self-similarity preferences might be specific to modern Western societies with the prevailing 'gay' system, where both partners identify as homosexuals 20 or gays, and are of similar sociodemographic characteristics. In other historical periods and/or other populations, this picture can be profoundly different, mostly characterized by gender stratified or age stratified same-sex relationships, where one partner is significantly more masculine or older than the other, respectively (Hames, Garfield, & Garfield, 2017;Murray, 2000;Werner, 2006;Whitam, 1983;Whitam & Mathy, 1986). ...
... Cardoso, 2005). The sexually, gender or age stratified partnering systems are suggested to reflect hierarchy between the partners, and hierarchical structures of the given society (e.g., Werner, 2006). ...
Preprint
Human sexual orientation is an intriguing phenomenon which is still poorly understood and has important evolutionary implications. Evolutionary based studies mostly focus on heterosexual individuals and relationships, probably because non-heterosexuality concerns a minority of the population and decreases individual direct reproductive success. To better understand human nature, it is important to analyse whether the mating psychology of minorities exhibit specific evolved sexual/reproductive strategies. Here we review studies on partner preferences, mate choice, and flirting in non-heterosexual populations, to identify which patterns are similar to or different from heterosexuals. The general pattern supports the notion that sex differences are larger than within sex variation among people of different sexual orientations. However, although some mating strategies among non-heterosexuals resemble heterosexuals of the same sex, others resemble heterosexuals of the opposite sex, and yet in others, the pattern is different than among either heterosexual men or women. We point to limitations of the current state of this research, and we suggest possible future directions in the study of non-heterosexual relationship initiation.
... Ignoring these distinctions, on the other hand, can create poor explanation due to mismatching SSB-type with evidence-type (Rind, 2015). For example, various authors have attempted to explain androphilia (with focus on men durably erotically attracted to other men) as an evolved adaptation facilitating bonding and mutually beneficial co-action (e.g., Barron & Hare, 2020;Kirkpatrick, 2000;Werner, 2006). But for supportive evidence they have typically relied on anthropological data involving age-stratified male SSB (between mature and immature males, or adults and adolescents), which, in fact, has been shown to actually operate in this manner. ...
Article
Full-text available
In the present study, relations between same-sex sexual behavior (SSB), age-class, and coalitional behavior in male rhesus macaques were examined in a re-analysis of data first analyzed and reported by Clive et al. (2023). Age-class as a focal variable was indicated in an extensive literature review, which showed that male non-adult (juvenile, adolescent) participation in SSB is extensive in this and related primate species and associated with various benefits. Clive et al. (2023) excluded juveniles from their analysis. In the re-analysis (n = 995 mounting events), it was found that non-adult involvement was substantial (51%). Most dyads contained at least one non-adult (76%). Young and prime adult mounters most often selected non-adults to mount. Mounters were often sexually motivated: most for adolescents (72%); equally for juveniles (57%) and adults (56%). Finally, the highest rate of SSB with coalitional context appeared in adolescent–adult dyads involved in multiple repeated mounts. SSB, age-class, special friendships, bonding, and coalitions were linked, as reported in some other primate species and human societies cross-culturally. Employing age-class in male SSB analysis improved description and explanation.
... Countless examples of same-sex behaviors from nonhuman species exist, enlightening our understanding of the basis of human sexual behavior (see Sommer & Vasey, 2006). Werner (2006) lists a diversity of occasional homosexual behaviors among primates, such as mounting of one male by another (e.g., langurs, pig-tailed macaques, baboons, orangutans, chimpanzees, bonobos), which can include mounting with anal penetration (e.g., stump-tailed macaques, squirrel monkeys), and mounting with anal penetration and ejaculation (Japanese macaques, rhesus macaques, gorillas). Some primates also perform mutual masturbation between individuals of the same sex (e.g., stump-tailed macaques), genito-genital rubbing (e.g., bonobos) that can lead to ejaculation (e.g., gibbons), and oral-penile sexual contact (e.g., stump-tailed macaques). ...
... Comparative perspective of samesex behavior in non-human primates is valuable for understanding the bases of human homosexuality. For example, Werner (2006) lists a diversity of same-sex behaviors among non-human primates, such as male-to-male mountingincluding anal penetration and ejaculation and masturbation between males, including mutual masturbation (some resulting in ejaculation). Other behaviors that may be related include sniffing/inspecting the genital/anal region among males, as well as the behavior of "showing off" the erect penis to other males and urinating a few drops on other males during the display. ...
Article
Full-text available
Homosexuality refers to sexual preference of individuals of the same sex/gender. This preference can occur in different dimensions, such as behavior, attraction, desire and fantasy, social identification with sexual orientation, and/or physiological arousal. It is influenced by interaction of internal (e.g., neurobiology, genes, endocrine functioning, etc.) and external (e.g., ecological and social) factors.
... 2. The genes that give rise to exclusive homosexuality also make homosexuals more likely to give economic or other support to their relatives, helping them raise more offspring (Vasey and Vanderlaan 2010) 3. The genes that give rise to exclusive homosexuality make their male and female relatives more cooperative with each other because they show a willingness to yield in disputes which gives the kin group an advantage in rearing children (Muscarella 2000, Werner 2006 There is some evidence for all of these theories: One study showed that the female relatives of male homosexuals were, indeed more fertile (Iemmola and Camperi 2009). Another study showed that homosexual males did indeed help their siblings raise more children (Vasey and Vanderlaan 2010). ...
Conference Paper
Full-text available
The evolution of dominance hierarchies heavily influenced our morality, politics, violence, sexuality and religion. This talk uses original cross-cultural correlations, as well as other evidence to examine many of the theories around this topic.
... 1. O mesmo gene que leva a homossexualidade exclusiva também torna mais férteis os parentes femininos dos homossexuais (Iemmola e Camperi 2009;Vanderlaan et al. 2014) 2. Os genes que levam à homossexualidade exclusiva também deixam os homossexuais com mais disposição para ajudar os seus parentes materialmente ou socialmente. o que os ajudaria a criar mais filhos (Vasey e Vanderlaan 2010) 3. Os genes que levam à homossexualidade exclusiva tornam os seus parentes mais cooperativos, pois demonstram uma disposição maior para ceder em disputas, o que dá uma vantagem ao grupo de parentes em criar filhos (Muscarella 2000;Werner 2006) Existe evidência para todas estas teorias. Um estudo descobriu que os parentes femininos dos homossexuais masculinos de fato eram mais fecundos (Iemmola e Camperi 2009). ...
Conference Paper
Full-text available
A evolução de hierarquias de dominância tiveram muita influência sobre a nossa moralidade, politica, violência, sexualidade e religião. Esta palestra examina correlações que comparam culturas diferentes além de outras evidências para examinar muitas teorias sobre a influência destas hierarquias.
... Heterosexual sexual behavior shows a similar diversity of expression across primate societies (Sommer and Vasey, 2006). It appears there has been an expansion of the social functions of sexual interactions (both homosexual and heterosexual) as more complex societies evolved in primates (Werner, 2006). As a consequence, sexual behavior in primates has been subject to selection for adaptive social functions as well as the obvious reproductive functions. ...
Article
Full-text available
Human same-sex sexual attraction (SSSA) has long been considered to be an evolutionary puzzle. The trait is clearly biological: it is widespread and has a strong additive genetic basis, but how SSSA has evolved remains a subject of debate. Of itself, homosexual sexual behavior will not yield offspring, and consequently individuals expressing strong SSSA that are mostly or exclusively homosexual are presumed to have lower fitness and reproductive success. How then did the trait evolve, and how is it maintained in populations? Here we develop a novel argument for the evolution of SSSA that focuses on the likely adaptive social consequences of SSSA. We argue that same sex sexual attraction evolved as just one of a suite of traits responding to strong selection for ease of social integration or prosocial behavior. A strong driver of recent human behavioral evolution has been selection for reduced reactive aggression, increased social affiliation, social communication, and ease of social integration. In many prosocial mammals sex has adopted new social functions in contexts of social bonding, social reinforcement, appeasement, and play. We argue that for humans the social functions and benefits of sex apply to same-sex sexual behavior as well as heterosexual behavior. As a consequence we propose a degree of SSSA, was selected for in recent human evolution for its non-conceptive social benefits. We discuss how this hypothesis provides a better explanation for human sexual attractions and behavior than theories that invoke sexual inversion or single-locus genetic models.
Article
Compared to the body of literature on male homosexuality, the continuum of bisexual orientations between the exclusively homosexual and heterosexual poles has been largely overlooked in the scientific and evolutionary literature. Possibly, male bisexuality is not as hard a puzzle to evolutionary thinking because it does not reduce individual direct reproductive success as much as exclusive male homosexuality. Or, bisexual men are expected to fall in between the exclusive poles of sexual orientation, and they thus would not differ from them in the studied characteristics. Moreover, the existence of bisexual men has sometimes been doubted or denied in scientific and lay literature. Despite recent Western biphobia (and homophobia) aimed specifically at men, we show that different forms of male sexuality aimed at both men and women are common among different human populations and non-human species, making it a viable candidate for evolutionary analysis. We first outline the concept and measurements of male bisexuality, its prevalence, and after reviewing the proximate socio-biological factors associated with male bisexuality, we outline evolutionary hypotheses on male bisexuality. We show that several hypotheses originally designed to explain exclusive homosexuality apply also to bisexuality, although most of them deal with the more feminine form of male non-heterosexuals. Finally, we outline the importance of studies on bisexuality for evolutionary psychological science.
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Full-text available
De onde vem a nossa capacidade de felicidade? Porque as hierarquias de dominância são tão importantes na religião, na cooperação humana, e na depressão psicológica? Qual a relação entre homossexualidade e demarcação de territórios? Porque o incesto foi incentivado nas famílias reais entre os egipcios, os havaianos, e os incas? Porque pais deixam que seus filhos os matem? Como construimos nossos símbolos? Para que serve a arte? Eis algumas das questões tratadas neste livro, que nos ensina algumas das sutilizes da teoria de evolução via seleção natural, ao mesmo tempo que aborda importantes questões sociais, políticas e psicológicas. Enquanto os teóricos da complexidade e da inteligência artificial exploram o algoritmo da seleção natural para desvendar possibilidades de emergência de novas estruturas, os psicólogos evolucionistas tentam esclarecer como surgiram as estruturas mentais que de fato possuimos.
Chapter
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"How can I swear to tell the truth? I can only say what I know. How can I know if this is the truth" -- Cree Indian testifying about a dam being built on his territory. This chapter distinguishes four different ways of conceiving the relationships between reality and thought. 1."NAIVE REALISM" ("a rose is a rose is a rose"), 2. IDEALISM ("Particular natural facts are the symbols of particular spiritual facts. Nature is the symbol of spirit...Every appearnace in nature corresponds to some state of mind". 3. Phenomenalism "All of life is a dream, and dreams are abut dreams"), and Evolutionism ("The miracle is not that the world has laws, but that we are able to understand them"). In explaining how the human mind evolved, the theory of evolution helps clarify the limits to our thought. Mathematics may help overcome some "absolute limits" to our thinking, while empirical tests can overcome many natural biases. We can neither "prove" nor "disprove" theories, but we can select in a manner akin to natural selection which theories are most in accord with the data. Cross-cultural studies can help verify which aspects of our thought are universal and these universals may help explain cross-cultural variation.
Article
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Morphometric analysis of the human hypothalamus revealed that the volume of the suprachiasmatic nucleus (SCN) in homosexual men is 1.7 times as large as that of a reference group of male subjects and contains 2.1 times as many cells. In another hypothalamic nucleus which is located in the immediate vicinity of the SCN, the sexually dimorphic nucleus (SDN), no such differences in either volume or cell number were found. The SDN data indicate the selectivity of the enlarged SCN in homosexual men, but do not support the hypothesis that homosexual men have a 'female hypothalamus'.
Book
Chronicle of life among the Mekranoti Indians, in the form of a traveller's journal, combining descriptions of individuals, subsistence systems, social organization, religion and other aspects of life interwoven in the text, along with references to systematic (statistical) studies published on these themes.
Article
This is the first collection of articles completely and explicitly devoted to the new field of 'comparative developmental evolutionary psychology' - that is, to studies of primate abilities based on frameworks drawn from developmental psychology and evolutionary biology. These frameworks include Piagetian and neo-Piagetian models as well as psycholinguistic ones. The articles in this collection - originating in Japan, Spain, Italy, France, Canada and the United States - represent a variety of backgrounds in human and nonhuman primate research, including psycholinguistics, developmental psychology, cultural and physical anthropology, ethology, and comparative psychology. The book focuses on such areas as the nature of culture, intelligence, language, and imitation; the differences among species in mental abilities and developmental patterns; and the evolution of life histories and of mental abilities and their neurological bases. The species studied include the African grey parrot, cebus and macaque monkeys, gorillas, orangutans, and both common and pygmy chimpanzees.