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Rob Brooks
Rob Brooks is director of the Evolution and Ecology Research Center at the University of New South Wales in Sydney, Australia. He is the recipient of the Australian Academy of Science Fenner Medal, and an internationally recognized expert on evolutionary biology and sexual conflict. His first book, Sex, Genes & Rock 'n' Roll: How Evolution has Shaped the Modern World is now out.

Entries by Rob Brooks

The Early Bird Gets the Sperm ... to the Egg

(0) Comments | Posted June 11, 2015 | 6:37 PM

What gets you out of bed in the morning? Before morning has broken, and some time before blackbird has spoken, songbirds rise for sex. And a clever new experiment reveals just how important it is for male songbirds not to sleep in.

A great many species of songbirds nest...

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O que a ciência nos diz sobre o corpo feminino 'ideal'

(0) Comments | Posted March 13, 2015 | 5:29 PM

Muitos estudiosos do Renascimento dizem que o quadro O Nascimento de Vênus (c. 1486, acima) capta a tensão entre a perfeição celestial da beleza divina e sua manifestação terrena e falha. Quando as ideias clássicas renasceram na Florença do século 14, Botticelli não pode ter deixado de entrar em contato...

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What Science Tells Us About the 'Ideal' Body Shape for Women

(20) Comments | Posted March 9, 2015 | 4:01 PM

Many scholars of Renaissance art tell us that Botticelli's Birth of Venus (c. 1486, pictured above) captures the tension between the celestial perfection of divine beauty and its flawed earthly manifestation. As classical ideas blossomed anew in 15th-century Florence, Botticelli could not have missed the popular Neoplatonic notion...

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Elections in the Time of Ebola

(0) Comments | Posted October 31, 2014 | 4:13 PM

How will the Ebola crisis influence next week's mid-term elections in the US? One might expect that an epidemic limited almost entirely to West Africa should be way, way down on the list of factors likely to swing American voters. What with ISIS, the economy, Obamacare, abortion and so many...

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O que nos faz humanos?

(0) Comments | Posted July 20, 2014 | 10:43 AM

O que separa os humanos dos outros animais, incluindo nossos parentes mais próximos?
É uma daquelas grandes perguntas perenamente postas pelo público evo-curioso. Mas até pouco tempo atrás eu raramente dava atenção a ela, basicamente porque as respostas tendem a se prender a um ou outro traço que nos...

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Economic Dependence Promotes Prudishness

(2) Comments | Posted July 9, 2014 | 6:38 PM

Stay home, bake white bread, don't sleep around. (Credit: Karen/Flickr.)

Marriage, according to those who habitually preface the word with "traditional," is a collaboration, with complementary roles, filled as predictably by one woman and one man as peanut butter fills the gap between two...

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What Makes Us Human?

(0) Comments | Posted June 4, 2014 | 1:08 PM

What separates humans from other animals, including our closest relatives?

It's one of those big questions perennially posed by the evo-curious public. But until recently I seldom gave it much thought, mostly because the answers tend to get hung up on one trait or another that differs from our closest...

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Worse Than Sex? 'M' Is for May and Masturbation Month

(17) Comments | Posted May 3, 2014 | 2:04 AM

The workers of the world can have their International Workers' Day, or Labor Day or whatever, but the month of May belongs to an equally fundamental dignity: masturbation.

The Divinyls' "I Touch Myself" polled most strongly among my Twitter followers, who were asked to nominate masturbation songs -- that is, songs about masturbation.

The fact that a whole month is devoted to self-pleasure raises two important questions: Who decides these things, and what are people meant to do over the 11 months from June through April?

On the former question, it seems that anyone can declare that a day, a month or even a year be dedicated to a particular cause. The UN endorses some of these. For example, last year, 2013, was both the International Year of Water Cooperation and the International Year of Quinoa. Oh, yes, it was!

Perhaps I needn't say it, but International Masturbation Month has not been recognized by the UN... yet.

Like many ideas surrounding sex, Masturbation Month is American. Formerly "National Masturbation Month," it did not require Republicans and Democrats working "across the aisle" to enact a special law. It only took a unilateral declaration of self-service by Good Vibrations sex shop in response to the firing of U.S. Surgeon General Jocelyn Elders.

Elders' dismissal followed comments at the UN World AIDS Day in 1994. Asked whether promoting masturbation might discourage school-aged children from riskier sexual activity, Elders agreed, noting that children should be taught that masturbation is a natural part of human sexuality.

The common-sense comments that got Jocelyn Elders fired from the post of U.S. Surgeon General.

Conservatives, already outraged by her progressive views on abortion and drugs, construed her as saying masturbation should be taught in schools. An embattled President Clinton, whose own seed-spilling later sucked the life out of his presidency, saw this as a step too far.

So, in Elders' honor, Good Vibrations says:

We started National Masturbation Month -- now International Masturbation Month with people celebrating across the globe! -- to raise awareness and to highlight the importance of masturbation for nearly everyone: it's safe, it's healthy, it's free, it's pleasurable and it helps people get to know their bodies and their sexual responses. Of all the kinds of sex people can have, masturbation is the most universal and important, yet few people talk about it freely -- worse, many people still feel it is "second best" or problematic in some way. Masturbation Month lets us emphasize how great it is: it's natural, common and fun!

Politics of the Pull

The U.S. political battle over masturbation that led to Elders' firing nearly two decades ago represents one minor shift in a centuries-old ideological tug-of-war over self-pleasure.

The history of attitudes toward masturbation -- from the ancient Egyptians, whose creator god Atum masturbated the universe into being and then generously continued to control the Nile's flooding by his ejaculations, to the ancient Indians with their rather athletic how-to instructions in the Kama Sutra -- makes for fascinating reading.

The cover of the 1875 Italian version of Samuel Auguste André David Tissot's pamphlet "Treatise on the Diseases Produced by Onanism." (Photograph by Giovanni Dell'Orto via Wikimedia Commons.)

The Judeo-Christian tradition has usually not embraced, and occasionally condemned, the solitary vice. But things got seriously weird in the 18th century, when masturbation attracted the blame for all manner of evils and ailments. One early pamphlet, published anonymously, really says it all in the wonderfully descriptive title: Onania, or the Heinous Sin of self-Pollution, And All Its Frightful Consequences, In Both Sexes, Considered: With Spiritual and Physical Advice To Those Who Have Already Injured Themselves By This Abominable Practice.

Nineteenth-century quacks such as Rev. Sylvester Graham lectured against the dire health consequences of "venereal excess" and the corrupting evils of self-pollution. Today much of his health recommendations look like common sense: exercise, bathing, brushing teeth, drinking clean water and consuming a diet of mostly vegetables and whole grains.

Visionary as he was, he is remembered because the bland diet he promoted, and the whole-wheat Graham cracker he invented, were designed to dampen libido. Likewise, the equally odd Dr. John Harvey Kellogg proclaimed, "If illicit commerce of the sexes is a heinous sin, self-pollution is a crime doubly abominable." Masturbation is worse than sex? Not as good, maybe, but worse? Kellogg's lasting contribution to suppressing libido was the insipid corn flake.

And it wasn't only the self-abuser who was in line to suffer. In "What a Young Woman Ought to Know," Mary Wood Allen counseled young ladies to consider the fate of their as-yet unborn offspring. Does this sound familiar?

The results of self-abuse are most disastrous. It destroys mental power and memory, it blotches the complexion, dulls the eye, takes away the strength, and may even cause insanity. It is a habit most difficult to overcome, and may not only last for years, but in its tendency be transmitted to one's children.

Touching the Enemy

All of this excitement proved baseless. Masturbation now seems, at least to the educated, to be the quintessential victimless crime, at least when practiced alone or among consenting adults, and as long as the method of fantasy doesn't impinge on anybody else's rights. Yet the subject still cleaves opinion in contemporary educated societies.

Consider the recent cringe-worthy campaign by Brigham Young University Idaho that considered modern masturbation and porn-use patterns alarming enough to erect a turgid war metaphor. The masturbators are personified by spent soldiers, left dying (and, it seems, tugging) on the battlefield by their fellows, which of course invites the question of what the soldiers are masturbating against in this so-called "Great War."

BYU Idaho took down their "Wounded on the Battlefield" video once the scale of their public-relations fail became clear, but it is still available within YouTube posts of segments such as this one.

Last May in The Atlantic, Hugo Schwyzer made a very interesting proposal regarding the controversy inherent to self-pleasure: "Tell me how you really feel about masturbation, and I can more or less predict how you'll feel about the more frequently debated 'sex war' issues."

His point was that all the issues at stake in the "sex wars," among which I would include the ideological tussles over abortion, contraception, promiscuity, sexual autonomy, sex education, mens' and womens' work and roles, homosexuality, gay marriage and even the importance of gender, are polarized over the question of what sex is for. If you believe sex is exclusively about connecting intimately with one other person and thereby producing children, then you will tend to take the conservative positions on these issues. You will also tend to view masturbation as wrong, wasteful or even sinful.

On the other hand, "delighting in something that, first and foremost, belongs to us as individuals" tends to be associated with more progressive attitudes about all these issues. And what purer expression of sex belonging to individuals can be found than the art of self-pleasure?

Who Wins? Who Loses?

Where does this tension about what sex is for come from?

Much resistance to masturbation turns on the perception that it represents a theft, robbing those who take matters in hand of their own health, vitality or ambition, or of taking something essential from the partner and the family unit. Some of the shame and stigma attached to masturbation in contemporary society prods at inadequacy. Calling someone a "wanker" implies that whatever they are doing, that isn't the way proper grown-ups roll.

Is masturbation only for losers, the terminally unattractive, and those stuck in sexless relationships? A large study of masturbation behavior in the U.S. suggests that the reality is far more complex. For some, masturbation "compensated for a lack of partnered sex or satisfaction in sex," while for others it "complemented an active and pleasurable sex life".

The fact that the most sexually satisfied subjects were also most directly in touch with their bodies supports the positions taken by Jocelyn Elders and others who maintain that masturbation is part of normal human sexuality. Masturbation is also most prevalent among the highly educated and those not in conservative religious groups -- that is to say those least likely to be swayed by supernatural or secular authority.

The narrow conception that sex is for procreation and the satisfaction of life-long spouses has served religions, monarchs and political leaders at various times. For one thing, it restricted the supply of sex. As I recently wrote, conservatives aren't too keen on an oversupply of sex, because that lowers the "price" -- how hard men have to work to have (proper, married) sex. Mark Regnerus, in-house sociologist at the conservative Austin Institute, warns, "Don't forget your Freud: Civilization is built on blocked, redirected, and channeled sexual impulse, because men will work for sex." But to whose ultimate benefit that work goes remains opaque.

The societal changes associated first with the Enlightenment, then with first-wave feminism and, eventually, the sexual revolution, concerned the elevation of the individual and the capacity for individuals, especially women, to own themselves. If people are not the property of a deity, a religious institution, or even a spouse, then they are not bound by the narrow conceptions of sexuality that suit the interests of those other "owners".

This line of thought may provide one reason that the Enlightenment, early feminism and the sexual revolution caused both new, more progressive attitudes to sex and strong backlashes -- led by the likes of Tissot, Graham, Kellogg and BYU Idaho -- against those new attitudes.

Have a good month appreciating self-ownership in your own chosen way.

Elvis Costello and the Attractions performing "Pump It Up" in 1978.

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organization that would benefit from this blog post and has no relevant affiliations.

This post was originally published on The Conversation. Read the original post

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Fear Not the Hipster Beard; It Too Shall Pass

(4) Comments | Posted April 16, 2014 | 9:09 PM

If you haven't been outdoors in a few years, you might not have noticed that beards are back. In fact, they're back in such a big way that many New York hipsters apparently are paying north of $8,000 for "facial hair transplants" to embellish their patchy beards.

While the...

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A Complex Cocktail: Alcohol, Sex and Cute, Monogamous Mammals

(0) Comments | Posted April 9, 2014 | 9:40 PM

Influencing the drinking patterns of others. Apart from being in a short, overly fussy glass and sporting a slice of lemon rather than a lime, the good thing about these gins and tonics is they were made by somebody else. And so I'm...

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'Don't Fear the Patriarchy, Girls -- Just Keep Your Panties On!'

(0) Comments | Posted February 28, 2014 | 6:48 PM

There's a video out there on the Intertubes that's got conservatives cheering and lefties in a lather. Actually, such videos are legion, but I'm talking here about a particular one with the rather broad and even-handed title of "The Economics of Sex."

You can watch...

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It Is Darwin Day, a Celebration of Science and Reason

(402) Comments | Posted February 12, 2014 | 9:13 AM

Happy Darwin Day!

Is that even an appropriate thing to wish somebody? Especially so close to Valentine's day?

Charles Darwin in 1868. The white-bearded patriarch that haunts every creationist and reason-denier. By Julia Margaret Cameron, Wikimedia Commons.

Darwin Day, according to the...

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Why the Masculine Face? Genetic Evidence Reveals Drawbacks of Hypermasculine Features

(2) Comments | Posted January 30, 2014 | 7:54 PM

Studying sex differences seldom gets boring. While the origins of differences in behavior and cognition remain fiercely -- and quite rightly -- disputed, we don't sweat quite as much about why women and men differ in size and strength. The Darwinian process of sexual selection, in which genes...

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The Selfie, the Tummy and the Act of War: A Dispatch From the Battle Over Female Attractiveness and Sexuality

(4) Comments | Posted December 5, 2013 | 12:22 PM

When is a selfie a selfie? And when does it become act of war?

Over at, Bec Sparrow has the answer. When the selfie is of six-packing fitness-blogging Norwegian Caroline Berg Eriksen posing in tiny underwear four days after giving birth, it's an act of war.

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Égalité Après la Guerre: How War Affects in-Group Fairness

(1) Comments | Posted November 26, 2013 | 2:56 PM

Over the last few evenings, I inhaled Robert Harris' novelisation of France's infamous Dreyfus affair. Told from the point of view of Colonel Georges Picquart, the intelligence officer whose scrupulous honesty finally established Dreyfus' innocence, An Officer and a Spy breathes life into historic events. Events...

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Gladwell and Goliath: When a Great Strength Becomes a Weakness

(9) Comments | Posted October 14, 2013 | 1:10 PM

Hasn't Malcolm Gladwell had a busy fortnight? His latest book, David and Goliath: Underdogs, Misfits and the Art of Battling Giants, shipped on the first of October. And the deluge of reviews washed out a flood of anti-Gladwell bile. He's an unusually polarising author, Gladwell. And it looks like...

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Religiosity More About Reproduction Than Cooperation

(107) Comments | Posted October 9, 2013 | 2:58 PM

Why do religious beliefs vary so broadly? I'm not talking here about the near-cosmic diversity in the content of religious belief, number and identity of deities, or types of practice. Rather, I'd like to consider why some individuals seem fervently devout while others seem devoid of any superstition.

This question...

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Have You Got the Balls to Be a Good Dad?

(2) Comments | Posted September 13, 2013 | 5:41 PM

Dads are important. Pardon the motherhood statement about... fatherhood. Just sometimes, even self-evident things need to be said. All else being equal, fathers who are involved in their children's upbringing directly improve those children's survival, health, social and educational development.

Jay-Z rhapsodises about becoming a dad, in Glory (featuring his daughter, Blue Ivy Carter).

Now for the second self-evident proposition: some dads are better than others. A great many dads lavish as much love and care on their children as those kids' mothers do. And many dads do more. Fathers make all sorts of deep, selfless, sacrifices to meet their children's needs.

But fathers vary enormously in how involved they are an in the ways they care. According to anthropologist Sarah Blaffer Hrdy, the contributions that fathers make to child caring and to the family vary dramatically among and within cultures. Far more dramatically, in fact, than the contributions mothers make.

What makes the difference, then, between a superdad and a low-investing or even absentee dad? What distinguishes a guy who raps lovingly about "the child he had with the child from Destiny's Child" from the papa who was a rolling stone?

The Temptations - sweet moves and even sweeter suits, in a 1972 performance of Papa Was a Rolling Stone.

Paternal trade-offs

Tempted as some might be to vilify low-investing men, evolutionary analysis usually seeks first to understand behaviour rather than to judge it. Evolutionary theory certainly can illuminate why fathers don't all invest equally. And an intriguing study, published this month, supports the idea of a biological continuum between high and low-investing fathers.

The key comes from life-history theory, which concerns itself with the economics of how organisms acquire resources and spend them on growth, reproduction, survival and other vital but costly activities. For example, just as one cannot spend the same dollar on rent and food, so one cannot spend the same kilojoule of energy on making sperm and on fighting off an infection. Different adaptive priorities trade-off with one another, just as different spending priorities trade-off within a household budget.

Most men lack the time, money and energy to be both sexually prolific and high-investing fathers at the same time. For some time, life-history theorists have postulated a trade-off between parental investment and mating effort -- the investment a man makes in finding, courting and mating with new partners.

No surprises there. Men who spend all their time, money and effort chasing new women are more likely to neglect or even abandon the children they already have. But how does this trade-off arise? Variation in testosterone among men, seems to be right in the middle of this issue:

On top of all this correlative evidence, experimental manipulation in a bird (the Lapland Longspur) reveals that testosterone supplementation directly increases a male's investment in courtship singing. This comes at the expense, however, of his effort attending the chicks.

Gone Daddy Gone. The Violent Femmes, who, incidentally, take all their equipment on the bus.

Testicle size

The size of a male's testes also correlates with investment in mating. Species in which females tend only to mate with one male in a given breeding cycle tend to have smaller testes than those in which sperm has to compete with that from other males for the chance to fertilise the same egg. Big testes equals more sperm equals more tickets in the great sperm lottery.

Within species, some evidence suggests that males with larger testes mate with more females and do so more often than less testicularly spectacular males. Large testes take energy to maintain. They also present a vulnerable liability, favouring compactness. Perhaps men whose bodies are biologically geared to invest in courting and mating with new mates might make the risky investment in larger testes, but those aiming for caring monogamy act to minimise their testicular liability?

In a 1995 book, Mark Bellis claimed that testes size was associated with sexual strategies in men. However, Leigh Simmons and colleagues at UWA found no such evidence in a 2004 paper. With this in mind, Jennifer S. Mascaro, Patrick D. Hackett and James K. Rilling from Emory University set out to test the relationship between testicular size, testosterone and men's parenting effort.

Kurt Cobain's father issues get a serious airing on Serve the Servants.

The Paternal Brain

Mascaro and her collaborators recruited 70 fathers, each with a child aged one or two, and each of whom were living with the child and the child's mother. The easy part was measuring male testes and plasma testosterone levels. They also administered comprehensive questionnaires to establish which parenting tasks each father performed, from the routine (bathing baby, attend child during the night) to the less common (taking the child to medical appointments).

Anyone who has parented alongside another knows that people don't always accurately estimate their contribution to the work of caring. So the researchers asked the mens' partners about who-did-what in the child-care department. Mums and dads actually agreed reasonably well on the division of labour.

And in a welcome development, the team used Functional Magnetic Resonance Imaging (fMRI) to explore brain activity in order to refine the picture of male parental investment. They observed how men responded to pictures of their own child, an unknown child and an unknown adult. And they used a variety of images, capturing a neutral expression, a happy or a sad face for each subject.

High testosterone levels and large testes were each, independently, associated with lower paternal caregiving. The authors interpret this as showing that high T and big testes result in lower paternal engagement. Especially since neither the number of hours men worked nor the amount they earned were correlated with testes size or with testosterone. It's not as if men switched from one form of investment to another.

I'm no neuroscientist, so I won't judge the quality of the evidence from that part of the study, but the claims are certainly promising. Fathers with small testes displayed more of the brain activity typically associated with nurturing when viewing pictures of their own child. Especially when the picture showed their child with a happy or sad, rather than neutral, expression. These same fathers were also better dads; at least they were more involved in caring for their infants.

Pearl Jam, in their prime, explore the nuances of paternity in Alive.

Dads: born and made

Nowhere in Mascaro's paper, in this column, or in the surrounding discussion I have seen, has anybody suggested the links are deterministic. Testosterone and testicle volume together only explained 21 percent of the variation in paternal caring. If you've got big (but healthy) testicles, that doesn't make you a bad dad. If you're low-T you may or may not be a good father, super responsive to your child's emotional state. So, fathers, I shouldn't have to say this, but don't take today's news personally.

The important point is that we're starting to come to terms with the complex interplay between biology and social behaviour involved in the all-important business of being a good father.

Collectively, these results provide the most direct support to date that the biology of human males reflects a trade-off between mating and parenting effort.

I wouldn't disagree with this conclusion. I'm amazed at how neatly the results uphold the prediction and the consistency of four lines of evidence: anatomic, hormonal, neuroscientific and social. This paper gives quite a firm idea of the way in which the trade-off works. And it begins to bridge several traditions of study to build a useful model of how biology and social factors interact to shape behaviour.

But why do men vary so much? I expect an avalanche of interesting research on this question. We do know that human life-histories vary from "fast" to "slow". Living fast involves early puberty and becoming a parent relatively young. It can be triggered by poverty, inequality, childhood neglect and, interestingly, father absence. Which can create a self-reinforcing cycle. Breaking that cycle involves lots of parental investment, both in nurturing and providing for material needs.

One obvious place in which to begin involves longitudinal studies to explore how the associations form between parental care, testicle size and testosterone. There are some exciting hints that low T men become better fathers, but do better fathers also experience a bigger drop in T? And how do testes wax and wane when men have kids? We don't really know much at all about whether and how testes size changes over men's lifetimes.

These many related areas of science remain quite some way off tying the complex mish-mash of factors that shape life-histories to the mating-parenting trade-off. But I believe research in this area has immense capacity to improve the lives of everybody involved.

I've enjoyed assembling videos of songs associated with fatherhood. Of course there are many, many more. Please Tweet me @Brooks_Rob with any good suggestions you want to share. Use #DadSongs.

Here are a few extras.

For Saffers of a certain vintage - Just Jinger, Father & Farther.

Little Man, by Tom Waits.

Father's Day, by Weddings, Parties, Anything.

And talking about testicles:

Down one end of the continuum in almost every respect, we find AC/DC.

Rob Brooks does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.
This article was originally published at The Conversation.

Read the original article.

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Blurred Double Standards

(5) Comments | Posted September 6, 2013 | 6:17 PM

All good books are different but all bad books are exactly the same. All these bad books have one thing in common: they don't ring true. (Robert Harris: The Ghost)

The same can be said, probably more so, for pop songs.

For months now I've been resisting the temptation to...

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Does It Matter That Atheists Are Smarter Than Believers?

(2591) Comments | Posted August 14, 2013 | 4:09 PM

News just in, guaranteed to stir smug nods from non-believers and incite irritation among the devout: intelligence correlates negatively with religious belief. You may have seen similar - or contradictory -- reports in the past. That's because scores of studies have asked if religiosity is associated with intelligence. But a...

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