Quotes I highlighted in Roughgarden's Evolution's Rainbow
Source: Roughgarden, J. (2013) Evolution’s Rainbow: Diversity, Gender, and Sexuality in Nature and People. University of California Press, Berkeley.
This is a chapter-by-chapter summary of all clauses I highlighted and annotated.
Table of Contents
Chapter 5. Two-Gender Families
Chapter 6: Multiple-Gender Families
Chapter 9: The Theory of Evolution
Chapter 1: Sex and Diversity
Eggs from an all-female species don’t need fertilization by sperm to trigger the cell divisions that generate an embryo. Females in all-female species clone themselves when they reproduce. (16)
Some species have two kinds of females: those who don’t mate when reproducing and those who do mate. (16)
All-female species are well-known among animals. (17)
Sexual reproduction cuts the population’s growth rate in half—this is the cost of sex. (17)
The benefit of sex is survival over evolutionary time. (17)
According to the diversity-repressing theory for the benefit of sex, sex protects the genetic quality of the species. The diversity-repressing theory envisions that asexual species accumulate harmful mutations over time and gradually become less functional. (20)
A bad gene never gets going in an asexual species, and sex’s supposed pruning of the gene pool is unnecessary and mythical. (20)
I accept as a working premise that a species’ biological rainbow is good—good because diversity allows a species to survive and prosper in continually changing conditions. I further accept that the purpose of sex is to maintain the rainbow’s diversity, resynthesizing that diversity each generation in order to continually rebalance the genetic portfolio of the species. I reject the alternative theory that sex exists to prune the gene pool of bad diversity. (21)
Overall, sex is essentially cooperative—a natural covenant to share genetic wealth. Sexual reproduction is not a battle. (21)
Chapter 2: Sex versus Gender
“Male” and “female” are biological categories, and the criteria for classifying an organism as male or female have to work with worms to whales, with red seaweed to redwood trees. When it comes to humans, the biological criteria for male and female don’t coincide 100 percent with present-day social criteria for man and woman. Indeed, using biological categories as though they were social categories is a mistake called “essentialism”. (23)
Essentialism amounts to passing the buck. Instead of taking responsibility for who counts socially as a man or woman, people turn to science...the definition of social categories rests with society, not science, and social categories can’t be made to coincide with biological categories except by fiat. (23)
In mammals...whether an individual is male or not comes down to making sperm, and the males in some mammalian species don’t have a Y chromosome. Moreover, in birds, reptiles, and amphibians, the Y chromosome doesn’t occur. (24)
Among humans...The key point here is that “male” and “female” are biological categories, whereas “man” and “woman” are social categories. (24)
“Gender” usually refers to the way a person expresses sexual identity in a cultural context. (27)
I suggest: Gender is the appearance, behavior, and life history of a sexed body. (27)
Misconceptions:
1. “An organism is solely male or female for life.” No, the most common body form among plants and in perhaps half of the animal kingdom is for an individual to be both male and female at the same, or at different times during its life. These individuals make small and large gametes during their lives.
2. “Males are bigger than females, on the average.” No, in lots of species, especially fish, the female is bigger than the male.
3. “Females, not males, give birth.” No, in many species the female deposits the eggs in the pouch of the male, who incubates them until birth. In many species, males, not females, tend the nest.
4. “Males have XY chromosomes and females XX chromosomes.” No, in birds, including domesticated poultry like chickens, the reverse is true. In many other species, male and females show no difference in chromosomes. In all alligators and crocodiles, some turtles and lizards, and the occasional fish, sex is determined by the temperature at which the eggs are raised. A female can control the sex ratio among her offspring by laying eggs in a shady or a sunny spot.
5. “Only two genders occur, corresponding to the two sexes.” No, many species have three or more genders, with individuals of each sex occurring in two or more forms.
6. “Males and females look different from one another.” No, in some species, males and females are almost indistinguishable. In other species, males occur in two or more forms, one of which represents a female, while the others are different from the female.
7. “The male has a penis and the female lactantes.” No, in the spotted hyena, females have a Penoi’s like structure externally identical to that of males, and in the fruit bats of Malaysia and Borneo, the males have milk-producing mammary glands.
8. “Males control females.” No, in some species females control males, and in many, mating is a dynamic interaction between female and male choice. Females may or may not prefer a dominant male.
9. “Females prefer monogamy and males want to play around.” No, depending on the species, either or both sexes may play around. Lifelong monogamy is rare, and even within monogamous species, females may initiate divorce to acquire a higher-ranking male. (27-28)
Chapter 3. Sex Within Bodies
Flexistyly is known in eleven families of flowering plants. The ginger’s diurnal sex change is not too different from how hamlets mate, where members of a mating pair switch back and forth between male and female once a minute.
Chapter 5. Two-Gender Families
Mate guarding, a male caging a female (50)
The distribution of reproductive activity throughout a group is called its reproductive skew. A social group where everyone participates has low skew...The reproductive skew in an animal society is the most fundamental attribute a society has from an evolutionary standpoint—the index of a society’s reproductive equity...Once in place, the skew sets a baseline for how each individual in the society structures a life plan for reproductive success. (65)
The inequality of reproductive opportunity initially available to different individuals is called a “distributional equity” by economists. (70) [Note: I do not include kin selection here because it has been summarily rejected as tautological with fatal evidentiary defects. - RXS]
Chapter 6: Multiple-Gender Families
One possibility is that two males together are more successful at attracting a female than one male is by himself...According to this theory, the fertilization’s obtained by the medium male are not stolen from the large male, but actually offered to him by the large male as an incentive to stay, a transaction based on reproductive opportunity. The courtship that precedes the medium male joining the large male’s territory amounts to a job interview, [Where the medium male resembles a female by coincidence; is the trait ungendered? Unbalanced theory imo. - RXS] (83)
[Note: “deceit” is a common & dangerous trope in HS readings and this is a good defused of that.] A simpler explanation is that territorial males who have not yet attracted a female are horny and invite romance with feminine males. Once the territorial males have attracted a female, they are no longer horny and no longer interested in courting a feminine male. A simpler explanation is that no one is deceived, no one forgets from year to year [who is male/female], and no one requires continual updating of his limited memory. A simpler explanation is that the two male birds who retire together into the nest hole are enjoying a romance. These birds many be neighbors building a cooperative relationship based on same-sex sexual attraction. The problem with deceit theories of animal behavior is that not only must some animals be implausibly dumb, but others must be remarkably devious—there must be great asymmetry in cognitive ability...scientists have not shown any such thing. (95-96)
Deceit theory is a trap. Deceit theory forces scientists to take sides on who is smarter—in this case, claiming that females are smarter than males. (96)
What seems common among all these feminine males is a lessening of hostilities. The cessation of hostility may be temporary...or be permanent. In either case, feminine imagery seems to be adopted by males to reduce hostility and promote friendship. (98-99)
[Scientists’] attitudes spin how animal behavior is interpreted and predetermine what data are taken. The expression “female mimicry” prevents the study of gender variation...so-called female mimics don’t exactly resemble females, and all the players have a long time to examine each other. I doubt that female mimicry exists anywhere outside the imagination of biologists. (101)
Thus biologists project scripts of their own prejudices and experiences with male-male competition onto animal bodies and use insulting languages about animals. Far from being a sexual parasite, why not see the silent male bullfrog as nature’s antidote to excess macho, preventing the controller from grabbing unlimited power? Far from being a cuckolder, why not picture the feminine male sunfish as nature’s peacemaker?. Biologists need to develop positive narratives about the diversity they’re seeing. (101)
Chapter 8: Same-sex Sexuality
The hunched posture used by the dominant male to solicit the mating is also used outside of courtship as a signal to reduce aggression after a territorial dispute. The solicitation of the [dominant male by the subordinate male pukeko, or purple swamp hen] could have a social significance in reducing overall hostility, and not have anything to do with competition for fertilizations...The female-female matings occurred only when eggs were about to be laid [perhaps to communicate between alpha and beta females about managing egg futures]. The lack of overt aggression among breeding females and males in the highly developed social system of pukekos, and same-sex matings clearly occupy a place in this social system. [134]
At least six situations lead to sex [for bonobos]: (1) Sex facilites sharing; (2) sex is used for reconciliation after a dispute; (3) sex helps integrate a new arrival into the group; (4) Sex helps form coalitions, (5) Sex is candy; (6was) Sex is used for reproduction. (149-150)
Chapter 9: The Theory of Evolution
Real species depart from the sexual selection norm [based on evidence]:
(1) Bodies do not conform to a binary model.
(2) Genders do not conform to a binary model.
(3) Sex roles are reversible.
(4) Sperm are not cheap.
(5) Females do not choose “great genes.”
(6) Family size is negotiated.
(7) Social deceit is not demonstrated.
(8) Same-sex sexuality is common.
(9) Mating is not primarily for sperm transfer.
(10) Secondary sex characteristics are not just for heterosexual mating. (169-170)
The uncritical acceptance of sexual selection theory has led to underestimation of the extent of cooperation among animals, forcing scientists to construe all interactions between organisms as somehow competitive...sexual selection theory is diversity-repressing…[and] incorrectly views gene pool diversity as consisting of mostly bad genes that males must eliminate and females avoid. (172)
Animals are not seeking each other’s genes; they are seeking access to the resources that each controls. Each animal has a time budget to allocate among between-sex and same-sex relationships...Males offer [...] a continual rebalancing of the species’ genetic portfolio. (175)
Some structures are used as a condition for inclusion in the same-sex social groups that control the resources needed to reproduce. (179)
Social-inclusionary traits pertain to both within- and between-sex social dynamics, and to relationships distributed across many individuals, not just dyadic relationships. Selection for social-inclusionary traits would seem to account for traits found solely in females of species that are not sex-role reversed, traits that presently lack any explanation...Social-inclusionary traits also provide an alternative explanation for many, if not all, of the traits conventionally interpreted as secondary sex characteristics in males, which, like the peacock’s tail, females are supposed to prefer. The problem is that the traits of the males with whom females wind up mating may be intended more for the attention of other males than for display to the females. (179)
Predating isolating mechanisms [such as color spots & vocalizations] tell what species [animals] belong to and avoid hybridized with other species. (180)
The selection pressure to reduce hybridization gradually disappears as species become more distinct from each other, stalling evolution before completion and leaving a residual hybridization rate. If the traits that separate species also function as social-inclusionary medals, then selection for social inclusion augments selection to lower hybridization and propels the evolution of species distinctness to completion. (180) [Note: I don’t know what author means here by “completion;” it seems contradictory to her main theme of dynamic change. - RXS]
Chapter 12: Sex Differences
SRY—a major gene affecting masculinity in mice and men, one of the gender genes—-comes into play. If males differ in SRY, they differ in an influential genes or how male gender is embodied. And SRY is one of the fastest evolving of all known genes. This gold standard of masculinity differs greatly across species. SRY is also variable across populations within a species, so the expression of masculinity is not constant from place to place within a species either. (211)
[Primate] evolution is clearly caused by natural selection, not random genetic drift, because new DNA molecules replace old ones faster at sites where the difference affects SRY’s protein than at sites where the substitution doesn’t change the protein. (211)
The protein made by SRY consists of a central portion called the HMG-box. The portions to the left and right, the flanking regions, are called the N-terminal and the C-terminal regions. The HMG-box portion doesn’t change much—this conserved part binds to the DNA and allows the SRY protein to affect how the DNA is translated. The evolutionary action is in the flanking regions, particularly the C-terminal region. (211)
Evolutionary changes in SRY outside of the HMG-box affect the gendered body. (211)
Chapter 13: Gender Identity
Three rice-grains of brain in and around the hypothalamus are sexually dimorphic in males and females—SDN-POA, BSTc, and VIP SCN. Of these, only BSTc differs between transgendered and nontransgendered people...The data supporting this claim may be thin but should be taken seriously. (238-239)
The three sexually dimorphic neural clusters vary independently of one another, leading to eight brain types, not two...these eight types of brains can be plugged into bodies with at least two genital configurations...leading to sixteen people types. (242) [note to self; ask neuro friends their take on this; this also doesn’t provide for less binary genital configurations]
One clue is that gender identity can’t occur much earlier than the third trimester of pregnancy is the absence of sex-hormone receptors from the brains of mid-trimester embryos. It has become clear that the external genitals differentiate before the brain does. (241)
Chapter 14: Sexual Orientation
The results demonstrate [of 46 brother-pairs in Canada] that there is no gay gene in Xq28. (253)
I believe that if a gay gene were a major phenomenon, its detection wouldn’t be so tricky. (254)
Gay sexual orientation is far more common than a genetic disease, and it is not associated with any physical disability (see p. 284). (256)
All in all, the data [from many surveys] do not support uncritical acceptance of homosexuality as deleterious (258)
[Note: reminder, kin selection theory has been invalidated] Nor does helping at the nest account for why such helpers would specifically be gay or lesbian. (258)
Sex-antagonistic pleiotropic homosexuality is theoretically far-fetched, has no supporting evidence, and relies on the false assumption that a gay gene lies within Xq28. (259)
The various theories advanced, some of them absurd, all suffer from an uncritical acceptance of homosexuality as deleterious. If homosexuality is an adaptation, then the commonness of homosexuality is no problem. (259)
The question becomes why everyone isn’t homosexual, as in bonobos. Overall, an evolutionary theory of human homosexuality needs to explain the polymorphism in sexual orientation among humans. (259)
One study contends that “the long history of institutionalized homosexuality between higher status and lower status males,” usually of different ages by five years or more, produces “relationships [that] tend to socialize the youths into the adult male role, nurture and protect the youths and provide the basis for life-long friendships, social alliances and social status...Social status, a reflection of political strength and alliances, appears to have played a large role in the evolutionary history of human male reproductive success. (259-260)
Homoerotic behavior in single-sex groups would reflect not an absence of partners, but the adaptive development of same-sex bonds and alliances in the conditions when they would be most useful, which may resemble the social structure of early hominids. (260)
Homosexuality leads to various types of alliances among males. As already noted, heterosexual and homosexual practice occurred together in fifteen out of twenty-one cultures. Homosexual behavior has also occurred more often in agricultural than in hunter-gatherer societies, and more often in larger social groups. Homosexual behavior may be more frequent when it empowers political networks rather than independent individuals, and it may be expressed more in industrial nations after their demographic transition from high reproduction to high survival. (260)
A difficulty faced by a theory of homosexuality as a form of alliance-building, however, is that male-male alliances can be built without using sexuality. (260) [Note: this could be simply one of many strategies maintained within a population depending on environmental factors -RXS]
I conjecture that polymorphism in sexual orientation may indicate alternative strategies of same-sex relationships that are equally effective in achieving access to net reproductive opportunity. These alternative same-sex relational strategies are the counterpart of alternative between-sex mating strategies. (260-261)
At one extreme, if everyone is in continual conflict, a cooperator can benefit by avoiding the hazards of conflict. In this view, homosexuality emerges as a complex social adaptation, a product of positive evolution. (261)
Chapter 15: Psychological Perspectives
Psychologists operate with a medical model that pathologizes diversity. (262)
[Note: Author states serious reservations about this chapter formed by nontransgendered reviews of transgendered people.] (262)
Mildred Brown and Chloe Rounsley...offer the most reliable account of transgender narratives collected by therapists that I have found. (264)
These narratives show that transsexualism begins with gender identity, not sex drive. Transgender expression appears before puberty and well before any conscious sex urges. (265)
There is a tendency [among therapists] to emphasize extreme quotations...the account of transgendered people as self-destructively hating their bodies has been greatly exaggerated by therapists. (266)
The theoretical goal of therapists is to construct a picture of the “true transsexual” as a reference standard for a sick individual who needs medical attention in every aspect of his or her life. (266)
After puberty, the lives of transgendered mena nd women cease being more or less mirror images.. At puberty and on into adulthood, cross-dressing by transgendered women becomes more frequent and deliberate. (268)
[Note: there exists huge variation in trans experiences just as in humans]
As far as I can tell, the vast majority of narratives freely told by transgendered people among themselves...demonstrate that actualizan gender identity—not sex drive—is the primary motivation for transgender expression. Narratives also show that body morphing practices, such as sex assignment and facial surgery, are done primarily to promote relationships...that surgery could be sexually arousing seems preposterous and insulting to them. However, even a single case of autoerotic transsexualism raises the issue of inclusion...After all, it shouldn’t matter why a sister becomes a sister...At the same time, the sensational publicizing of autoerotic transsexualism poses a threat to the future of transgendered people [by undermining it] with bizarre sexualities. (273) [Note: use of “bizarre sexualities” is Author’s, not mine. -RXS]
Therapists sort their adult clients into the “knowing” and the “confused.” (277)
A transgendered person’s conception of what it means to be transgendered is influenced by whether the first encounter is with a therapist or through contact with the trans community. The therapy route is more stigmatizing, as a result of its framing of transgender expression as a disease needing a cure. (276)
Chapter 16: Disease versus Diversity
Any genetic trait is an investment that may pay a dividend in offspring at some time and place. Only an inherited trait deleterious under all conditions can be considered a genetic defect. Furthermore, a trait that is deleterious under all conditions is necessarily rare (because it’s continually being opposed by natural selection). Thus, to be a genetic defect, two scientific criteria must be satisfied—the trait must be extremely rare and the trait cannot be advantageous under any condition. If one of these criteria is not met, then the trait cannot be considered a genetic defect. (281)
[Author assumes] Genetic defects are automatically weeded out over time by natural selection. The only way defects resurface is by mutation from adaptive genes into deleterious forms. The degree of rarity for a genetic defect is set by a balance between the two rates: the rate of formation by mutation and the rate of elimination by natural selection. This level of rarity is called a mutation-selection equilibrium (281)
[Note: in table of relation between rarity and severity of disease on 282 based on % reduction in Darwinian fitness, none of the gender & sexuality frequencies fit in the range of biologically accepted “genetic defect” (282)]
Until now, no one has seriously considered the possibility that being transgendered is adaptive. (287)
Hypospadia—[a condition where the] urethral opening on the penis vents below the tip. Although the assumed normal opening is at the tip, a study of 500 men revealed that only 55 percent had urethral openings there, whereas 45 percent had the opening somewhere below the tip. If the opening is somewhere in the bulbous end of the penis (the glans penis), the hypospadia is considered minimal, and one in every two boys seems to have such mild hypospadia, although the point at which it is noticed at all varies among pediatricians. If the opening is along the shaft or below the penis on the body wall, it is called medium or severe, and the commonness drops in 1 in 1,725. (288) The next most common bodily state lumped under intersexuality is called congenital adrenal hyperplasia (CAH). There area dozen or more sub variety of CAH. A gene called CYP21 on an auto some (chromosome other than X or Y) makes a protein that catalyze the conversion of progesterone to cortisol, a stress hormone, in the adrenal glands next to the kidneys. If this gene is absent or blocked, then progesterone accumulates, which is androgen is in itself and is also converted to other androgens, like testosterone, outside the adrenal glands. (289)
So-called nonclassic or late-onset CAH is the most common, and refers to CAH that arises anytime after the first five years of life. (289)
In contrast, classic CAH is observed at birth in females as ambiguous genitals that may include not only a large clitoris but also fused labia comprising a partial scrotum and a urethra contained in the clitoris, making a micro penis, together with a uterus. In males, the genitals offer little clue. (289)
Two-thirds of classic CAH people also lose or “waste” salt because the adrenal glands don’t produce an additional hormone needed for salt metabolism. This salt-losing or salt-wasting version (SL-CAH or SW-CAH) is contrasted with the version applicable to the remaining one-third of classic CAH people, called simple-virilizing (SV-CAH), which does not affect functional salt metabolism. Without being given cortisol and other hormones made by the adrenal glands, SL-CAH people are likely to die as infants. Mor males die of SL-CAH because their genitals do not suggest a diagnosis that salt metabolism is at risk, whereas the risk in females is more likely to be diagnosed because fo intersex genitals...One tail of the distribution of CAH people does arguably suffer from a genetic disease: salt-losing CAH is genetic, painful, life-threatening, deleterious under all circumstances,a nd arguably rare enough to represent a mutation-selection equilibrium in the gene pool [, but people on the other side of the spectrum are stigmatized]. (290)
A form of intersexuality called androgen insensitivity syndrome (AIS) pertains to people whose sex chromosomes are XY. The Y chromosomes with its SRY gene helps the gonads to differentiate as testes and produce testosterone, while the X chromosome contains a. gene that produces receptors for testosterone. This gene, called Xq11-12, has many alleles (150 to date), which determine how much effect testosterone can have on the body. Thus, how much body masculinity is expressed by SRY on the Y chromosome depends on the outcome of its negotiation with Xq11-12 on the X chromosome. AIS is characterized by a very feminine body in an XY individual, as a result of receptors that don’t bind strongly to testosterone so that the body’s testosterone has little effect on the body’s appearance. AIS comes in three major classes. (291)
Complete AIS does arguably qualify as a genetic disease. Although not necessarily painful, complete AIS is deleterious to fertility and rare enough to represent a mutation-selection equilibrium. Partial AIS, however, could simply Inter grade with various non diagnosable body types that are relatively androgynous and would be scored as normal. (291)
In summary, the descriptions of genetic and hormonal aspects of intersexuality are more extensive than for gender identity and sexual orientation because intersex bodily states form earlier in development than sexual orientation and gender identity. The most common forms of intersexuality differ only cosmetically from nonintersexes. (293)
Notice the clever—and dangerous juxtaposition of homosexuality with dull-wittedness and attention-deficit disorder. You can’t cure homosexuality because there’s no disease to cure. (295)
Various interventions have been tried to encourage children to assume gender-typical behavior. The children simply reverted to cross-gender behavior in the adult’s absence or at home. In addition, the children didn’t generalize to forms of behavior not presented to the adult. (295)
Transgender activist Patric Califia recently commented, ‘None of the gender scientists seem to realize that they, themselves, are responsible or creating a situation where transsexual people must describe a fixed set of symptoms and recite a history that has been edited in clearly prescribed ways in order to get a doctor’s approval for what should be their inalienable right. (297)
When gays were asked [how many gay people would wish they were straight?], they often wished to be “cured,” but they say this much less today. (297)
The wording of the diagnostic criteria for GID [fails] “to acknowledge happy, well-adjusted transgendered people,” according to psychologist Kate Wilson. Paul Vasey [charges] that GID doesn’t meet the DSM-IV’s own criterion for a mental disorder, and that it “should not appear in future editions of the DSM.” Pathologizing transgendered people indirectly marginalizes the few health professionals who do work with his group. (298)
I believe being transgendered, like being pregnant, is best viewed as a normal human condition whose expression is aided by medical service. (298)
The issue is, rather, the pathologizing of diversity. Transgender procedures should be considered a medical service required for personal growth, not a therapy to cure a disease. (299)
Penis size at birth is the primary criterion for forcing a gender reassignment on the child. (300)
The phallometer [Intersex Society of North America] is a ruler with 0.20 to 0.85 marked off as female and 2.5 to 4.5 marked off as male...Simple. Too simple. (300)
Today, clinicians seem to be focused not on whether their approach to intersex people must be rethought, but rather on how to improve technique. (300)
For AIS patients, the immediate health risk is minimal. (301)
One theme of intersex advocacy is that an infant’s genitals should be left alone so that the child can elect later whatever plastic surgery he or she feels is needed. A second theme is that the child should be told the truth. Finally, intersex advocates stress that any procedure should benefit the child, not please the parent. (302)
This emphasis on treating the child to please the parents is typical of how LGBTI people are handled by the medical community. (302)
[re: circumcision] Imagine a species in which all males have a penis requiring surgical repair. (303)
Drug companies have a staggeringly huge incentive to convince everyone that they’re sick. [Note: Author suggests health insurance incentivizes pathologizing.]