The Feminist Egg

Once upon a time, I suppose that one of the characteristics of Age was its hubris. After a certain age, it was easy to dismiss most new things as mere variations on time-tested themes –additions, clever perhaps, intriguing even, but still accretions. Ecclesiastes lived in old minds: The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun. And yet nowadays, even the quickest peek over the shoulder calls that into question. Maybe it always did, but without the publicity it now entertains.

New things –truly new things- are often the hardest to accept, especially if they fly in the  face of cherished beliefs sufficiently entrenched as to be regarded as not merely true, but obviously true -common sense, in fact. It took generations to accept evolution –and now it seems only sensible that the random acquisition of those traits that help survival will be the ones selected for in the next generation. It was not an upwardly purposeful spiral that inevitably led to homo sapiens; evolution doesn’t change cows to humans –it just eventually creates cows better able to survive in whatever milieu they find themselves. And randomly –the unfit are still granted existence, but if they are not suited, they pass on little benefit to their progeny.

It’s true that animals –mammals, especially- do attempt to influence desirable traits in their offspring by choosing healthy partners exhibiting those characteristics. Hence various mating rituals and dominance contests amongst the males; hence elaborate male bird plumage, presumably a proxy, recognizable by a receptive female, as indicative of a primus inter pares. And yet it was probably regarded as curious in premodern societies that a female would be accorded any important choice, let alone that of selecting what she wanted in a partner. Although there has always been a cadre of women who have made their marks throughout recorded history, the examples are sadly limited –curtailed no doubt, because it was usually men writing about what they felt was important to document.

Fortunately, times are changing, as is the realization that each side of the gender divide is equipotent. Just how fluid the roles are is a constant source of wonder to me. Even in these days of Darwin, I am amazed at the still unsuspected porosity of the envelope. And while it no longer seems unusual or unlikely that an information-processing organism like, say, a bird might be able to select an appropriately endowed mate based on observable clues, it is still surprising –to me, at least- that selection duties might be conferred on a more microscopic scale: on an egg, for example.

I first encountered this idea in an article from Quanta Magazine: https://www.quantamagazine.org/choosy-eggs-may-pick-sperm-for-their-genes-defying-mendels-law-20171115/  I have to say it reminded me of Hamlet’s rejoinder to the sceptical Horatio on seeing Hamlet’s father’s ghost: ‘There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.’

The competition in sexual selection was thought to be pre-copulatory –‘After mating, the female had made her choice, and the only competition was among the sperm swimming to the egg. This male-oriented view of female reproductive biology as largely acquiescent was pervasive, argued Emily Martin, an anthropologist at New York University, in a 1991 paper. “The egg is seen as large and passive. It does not move or journey but passively ‘is transported’…along the fallopian tube. In utter contrast, sperm are small, ‘streamlined’ and invariably active,” she wrote.

‘Beginning in the 1970s, however, the science began to undermine that stereotype. William Eberhard, now a behavioural ecologist at the Smithsonian Tropical Research Institute, documented all the ways that females can affect which males fertilize their eggs even after mating.’ For example, ‘Internal fertilizers have their own methods of what Eberhard dubbed “cryptic female choice.” Some female reproductive tracts are labyrinthine, complete with false starts and dead ends that can stymie all but the strongest sperm. Some females, including many species of reptiles, fish, birds and amphibians, that copulate with more than one male (which biologists estimate are a vast majority of species) can store sperm for months, even years, altering the storage environment to stack the odds to favor one male over another. Many female birds, including domestic chickens, can eject sperm after mating , which lets them bias fertilization in favor of the best male.’

The plot thickens. These strategies seem only to select whose sperm to allow access to the precious as-yet unfertilized eggs. But even sperm from the same individual can vary. So, are things just left to chance? Are we still talking Darwin here? And are the combination probabilities proposed by Mendel that depend on randomness still in the picture?

It would seem that the egg itself may have a say in which sperm it uses, and that unlike the voting system in many democracies, it may not be just the ‘first past the post’ -the marathon winner- who gets the prize.

The article presents several theories as to how the egg may be able to ‘choose’, but as yet there seems to be no clear indication as to whether it always happens, or whether it is just able to weed out some potentially damaging or clearly unsuitable ones by the signals they emit –or fail to emit… Sometimes, anyway. Mistakes clearly occur; abnormal genes do manage to slip through, leading to abnormal embryos –some of which are unable to develop enough to survive.

But that there may be yet another layer of protection built into the system –another unsuspected surveillance system- is what intrigues me. And that, once again, it seems to invest the power of a truly critical decision with the female is a cautionary tale for those who cling to the shredding coattails of androcentrism. It is simply another piece of evidence, if more were needed, that Life and all that it enables, is not a zero sum game. It is not a contest between genders, but a journey together. Still…

Let there be spaces in your togetherness.                                                                                      And let the winds of heaven dance between you.
Love one another, but make not a bond of love.
Let it rather be a moving sea between the shores of your souls.
Fill each other’s cup but drink not from one cup.
Give one another of your bread but eat not from the same loaf.
Sing and dance together and be joyous, but each one of you be
alone – even as the strings of a lute are alone though the quiver
with the same music.
Give your hearts, but not in each other’s keeping.
For only the hand of Life can contain your hearts.
And stand together yet not too near together:
For the pillars of the temple stand apart,
And the oak tree and the Cyprus grow not in each other’s shadows. –Kahlil Gibran –

I couldn’t resist.

 

 

 

 

 

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Pleasing Her: sexual evolution?

I came across an interesting article in the magazine Science a while back. I am always intrigued when a paper tries to place an issue in its ontological context, although I have to confess that the title had something to do with catching my eye. It was a scientific theory from seemingly reputable sources about the evolutionary significance of the female orgasm. http://www.sciencemag.org/news/2016/08/new-theory-suggests-female-orgasms-are-evolutionary-leftover  The article to which it refers is more detailed and helpful, but somewhat difficult to read; to get a more comprehensive description of the process however, I will include it here for reference: http://onlinelibrary.wiley.com/doi/10.1002/jez.b.22690/full

Orgasm is a topic that seldom surfaced through all the years of my gynaecologic practice; it was something that many women felt too embarrassed to mention –especially to a male doctor. It was also a subject that I felt ill-prepared to tackle –apart from standard psychological advice of dubious merit, the only benefit seemed to be that of a sympathetic, nonjudgmental hearing. Little was known about either the function or the physiology of orgasm, so advice about its production was more anecdotal than beneficial; it was therefore usually the purview of sexual dysfunction clinics rather than that of the general gynaecologist.

The only thing that seemed on a firm basis with regards to orgasm was that it was essential in males for sperm transfer. Clitoral stimulation is usually required for the production of female orgasm, and since the penis and clitoris share a homologous origin perhaps it was simply a fortuitous consequence of this –a secondary adaptation (exaptation) for the purposes of bonding, or the like.

But to place female orgasm on a more secure footing, the authors have looked at reproduction in other animals. ‘The essential condition for the success of internal fertilization is the timely maturation and release of the oocytes from the ovary into the female reproductive tract, that is, ovulation, for the egg to be accessible to sperm. These events need to be coordinated with the availability of males and favourable environmental conditions for raising the young.’ And for such, there are roughly three factors that might influence induction of ovulation in mammals: environmental –cues that suggest it would be a favourable time for successful rearing of offspring such as weather, food sources, etc.; copulation induction –only produce valuable eggs when they’re needed –i.e. when a mate is available; and spontaneous ovulation –no matter the availability of mate or suitable environment. Humans, it would seem, utilize the latter option –spontaneous ovulation.

In copulation-induced ovulation, a surge of two hormones in the female are required –prolactin, and to a lesser extent oxytocin. Interestingly, these are also produced during human female orgasm, although with spontaneous ovulation in humans, they are not specifically required. As the authors suggest: ‘The orgasm in women does not obviously contribute to the reproductive success, and surprisingly unreliably accompanies heterosexual intercourse. Two types of explanations have been proposed: one insisting on extant adaptive roles in reproduction, another explaining female orgasm as a byproduct of selection on male orgasm, which is crucial for sperm transfer.’ In other words, ‘Human female orgasm is associated with an endocrine surge similar to the copulatory surges in species with induced ovulation. We suggest that the homolog of human orgasm is the reflex that, ancestrally, induced ovulation. This reflex became superfluous with the evolution of spontaneous ovulation, potentially freeing female orgasm for other roles.’

There is another aspect of the study that fascinated me –something that had not registered despite my years as a gynaecologist: ‘With the evolution of spontaneous ovulation, clitoral stimulation lost its role in ensuring fertilization simultaneously with the removal of clitoris from the copulatory canal, likely causing a variable association between copulation and orgasms for the female.’

Think about it. Why would the homologue of something important for ovulation in some species, and so important for orgasm in ours have moved away from the action? The clitoris is now located quite a distance from the vagina and is only inadvertently stimulated with human heterosexual intercourse. I think the Science article expressed it well: ‘Humans and other primates don’t need intercourse to trigger ovulation—they evolved to a point where it happens on its own—but the hormonal changes accompanying intercourse persist and fuel the orgasms that make sex more enjoyable, the biologists hypothesize. And because those hormonal surges no longer confer a biological advantage, orgasms during intercourse may be lost in some women. This explanation “takes away a lot of stigma” of underwhelming sexual relations, says one of the authors, Mihaela Pavlićev, of Cincinnati Children’s Hospital in Ohio.’

And also: ‘Pavlićev and Wagner’s theory helps explain why female orgasms during intercourse are relatively rare. “It is new to use [this] innovative, Darwinian approach to understand one of the mysteries of human sexuality—why the male orgasm is warranted, easy-to-reach, and strictly related to reproduction and the female counterpart [is] absolutely not,” says Emmanuele Jannini, an endocrinologist at University of Rome Tor Vergata. The nonnecessity of orgasms for reproduction may also explain why women’s reproductive tracts vary a lot more than men’s—there are fewer constraints, he adds.’

I have to admit that this was all terra incognita to me. And a clarification and reassurance for those few women who confided concerns about their difficulties or even inability to achieve orgasm with heterosexual intercourse seemed impossible if it was supposed to be part of the process. Surely they weren’t all psychologically liable… So-called foreplay was clearly important –if only to stimulate both the clitoris as well as interest in the procedure- but was there something wrong with them if he couldn’t be persuaded?

Satisfactory sexual experience is clearly important and helps to provide the glue that bonds a relationship. But does the changed anatomy tell us anything? Might we be permitted a secular Darwinian postulate that pleasure may, after all, be divorced from the procreative imperative? A sort of anatomical excuse? Much can be done to wrap this in a more attractive package -the counselling of both partners as well as suggestions on technique- but at least from an evolutionary perspective that seeks to propagate our species, we’re doing just fine. Maybe too fine, in fact…