Sex is a costly molecular kind of wizardry – why evolve it?

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Arunas L. Radzvilavicius in Aeon:

At its heart, sex is a process of genetic mixing: it creates unique sets of genes and trait combinations different from either of the two parents. In eukaryotes (organisms such as animals and plants), the molecular machinery of recombination deliberately breaks the chromosomes into chunks, only to reunite the pieces of maternal and paternal origin into novel permutations that are then passed on to the progeny: a remarkable act of molecular wizardry, perfected over billions years of evolutionary tinkering.

But it is not the molecular workings of recombination that captivates biologists the most, it’s the fact that genetic mixing in the form of sex has evolved in the first place, in spite of it being a cumbersome and costly endeavour. Evolutionary theorists agree that cloning, in many ways, is a more efficient mode of reproduction, which, in a world governed by the rules of natural selection, should readily outcompete sex. An asexual female, for example, would produce twice as many offspring as the sexual one, avoiding the burden of bearing males or searching for suitable mating partners.

Sex is unknown in bacteria – the simplest and most ancient living cells on Earth – that reproduce by simply splitting into two. Evolving considerably later, eukaryotes are built of much larger and awfully complex cells, their insides full of organelles and membranous labyrinths buzzing with sophisticated molecular machinery and cargo-transport networks. Unlike bacteria, very few eukaryotic species revert to strict asexuality, and those that do seem to be relatively short-lived on the evolutionary timescale. Sex is costly, but it also appears to be essential for the long-term survival of complex life.

Some of the most talented theorists have striven to understand why. Myriad explanations made their way into science journals and textbooks – from the earliest proposals that sex generates variation and speeds up adaptation, to mathematical models demonstrating that gene shuffling bolsters resistance to parasites and slows down the accumulation of hazardous genetic defects. But even with the overwhelming amount of attention the problem has received over the years, it is still considered unsolved.

Why?

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Four Words

Amy Davidson in The New Yorker:

PulseOf all the words that Donald J. Trump flings into the world, the four most Trumpian are “We have no choice.” It’s a favorite phrase, and one that he used last week in response to the attack at Pulse, a gay dance club in Orlando, where Omar Mateen shot and killed forty-nine people and wounded fifty-three more. Mateen was an American, born in New York to Afghan parents. Yet Trump said the lesson of Orlando is that “we have no choice” but to institute a temporary ban that would prevent non-citizen Muslims from entering the United States. He said the same thing when he first called for the ban, last December, after the San Bernardino shooting. That time, he chanted it in triplicate—“We have no choice! We have no choice! We have no choice!”—as if it were a spell that would make him Presidential, or make his listeners forget that he is not.

Trump has invoked choicelessness to explain everything from why he will build a wall on the border with Mexico to why he talked about his anatomy during a Republican primary debate. The phrase is a dismissal of rational discussion and an intimation of the doom that awaits if Trump is not heeded. In his recent book, “Crippled America,” he said of his decision to run for the White House, “I had no choice. I see what’s happening to our country; it’s going to hell.” Orlando was the first major domestic-terrorism crisis since Trump became the presumptive Republican nominee. His first response was to brag about “the congrats” he’d been receiving for having been “right on radical Islam.” Over the next few days, he suggested that President Obama had willfully failed to stop the shooting, for mysterious and possibly sinister reasons (“There’s something going on”), and accused American Muslims as a group of being similarly delinquent. He said, “They’re not reporting people, and they have to do that,” and insisted that America is “not going to continue to survive like this.”

More here.

This brilliant book sheds new light on Nazi Germany

Sir Ian Kershaw in The Telegraph:

Dachau-secon-large_trans++P_Bom7PPgEJsiWyV1eY9v4Fe_1VlDExwnQyrxoUgD38So what is new about Wachsmann’s book, and why is it so important? Odd as it might seem, his is the first comprehensive study of the camps, based on mastery of a huge literature and stupendous research in many parts of the world. Its value lies in no small measure in the way it weaves together the history both of the perpetrators and of the victims. Wachsmann tells the terrible story through the eyes of those who inhabited the camps. He writes of the camps as places where people lived. Prisoners become individuals, not just objects of terror. The behaviour of guards is shown to be more complex than mere sadism and brutality. A great virtue of the book is the way in which Wachsmann differentiates the camps. He shows the differences in organisation and structure as the vast camp network develops. For many readers, these differences will be new. The best-known camps are Dachau and Auschwitz. Both were places of horror, but with different purposes. Dachau, near Munich, was the prototype SS camp, meant to be widely known as a deterrent to opponents of the regime, especially at first communists. It served to hold prisoners who were subjected to arbitrary terror and forced to labour until the point of exhaustion, without any judicial protection, until (at least in theory) they were fit to rejoin society as compliant citizens.

Auschwitz, in a part of Poland annexed by Germany in 1939, had all this too, aimed primarily at recalcitrant Poles, but was unique within the system because it was an extermination camp as well as a concentration camp. The death camps further east in German-occupied Poland (Belzec, Sobibor and Treblinka), on the other hand, operated outside the concentration camp system. They did not imprison people and force them to work. Their sole purpose was to kill the Jews – close on two million, nearly all from Poland – as quickly as possible. But within the KL system itself, Jews were a minority among the prisoners. The Holocaust, as Wachsmann emphasises, mainly took place outside the concentration camps.

More here.

Saturday, June 18, 2016

THE LAST BOOK MY FATHER READ

Patrick Ryan in Literary Hub:

ScreenHunter_2044 Jun. 18 19.59My dad worked a lot of jobs. As a young man, in Ohio, he repossessed cars for a summer. (“Don’t ever repossess cars,” he told me. “Nobody likes you. I had to carry a baseball bat and keep a loaded pistol in the glove compartment, just in case of trouble.”) He then worked as a desk clerk at a hotel in Washington DC. Later, at Kennedy Space Center in Florida, he stood in a caged room all day and checked out camera equipment to staff photographers. When the Apollo program began to wane in the mid-1970s, he quit ahead of the layoffs that were coming, honed his skill at fixing cars, and got a job as an auto mechanic. But after a few years, the owner retired and sold the garage.

And so my dad mulled around for a bit and flirted with the idea of becoming his own boss. He looked into opening a liquor store, a cafeteria-style restaurant, a wholesale inner tube business. But he lacked the one thing a man with a dream needs to get anywhere: capital. He would become a realtor, he decided. He would sell houses. He got his license and tried that for a while—just as the real estate market in the area was entering a major slump. By coincidence, his marriage to my mother was also in a slump; they separated on the eve of their 23rd wedding anniversary and divorced soon after.

More here.

Birds Have More Neurons in Their Brains than Mammals, Study Finds

From Sci News:

ScreenHunter_2043 Jun. 18 19.46The study, published online this week in the Proceedings of the National Academy of Sciences, provides a straightforward answer to a puzzle that researchers have been wrestling with for years: how can birds with their tiny brains perform complicated cognitive behaviors?

“For a long time having a ‘bird brain’ was considered to be a bad thing. Now it turns out that it should be a compliment,” Dr. Herculano-Houzel said.

Dr. Herculano-Houzel and co-authors systematically measured the number of neurons in the brains of 28 avian species ranging in size from the tiny zebra finch to the emu.

“We found that birds, especially songbirds and parrots, have surprisingly large numbers of neurons in their pallium: the part of the brain that corresponds to the cerebral cortex, which supports higher cognition functions such as planning for the future or finding patterns,” Dr. Herculano-Houzel said.

“That explains why they exhibit levels of cognition at least as complex as primates.”

That is possible because the neurons in avian brains are much smaller and more densely packed than those in mammalian brains.

More here.

A Literary Journey Characterised by Tenderness and Grit

Amy Finnerty in The Wire:

ScreenHunter_2042 Jun. 18 19.28Upon learning this month that his autobiographical novel Family Life had won the €100,000 International Dublin Literary Award — the world’s richest prize for a single novel — Akhil Sharma exhaled, thinking: “Thank God, another disappointment averted.” He received the news in a hotel room in Guatemala.

It makes sense that the India-born, Manhattan-based American novelist, journalist and professor of creative writing remains ever alert to bad news. When he was eight years old and his family moved from Delhi to New York in the 1970s brimming with hope, they could hardly have imagined that his older brother, Anup, the character Birju Mishra in the book, would soon be catastrophically disabled in a swimming pool accident: left permanently brain damaged, blind, unable to speak and requiring round-the-clock care for the rest of his life. (He died just four years ago). Family Life puts the prolonged and harrowing ordeal under fluorescent lights.

The author of an award-winning first novel, An Obedient Father, Sharma spent 13 years wrestling Family Life onto the page, a process he has likened to “chewing gravel”. A few years in, despairing and overweight, he says, he gave up on the project. Then he started running inhuman distances every day and, accessing the grit that he’s used to succeed at pretty much everything he’s ever set his mind to, he staggered across page 218 and handed in the manuscript to his editor, Jill Bialosky at Norton.

More here.

Jenny Diski’s ‘In Gratitude’

19JULAVITS-blog427-v2Heidi Julavits at the New York Times:

Jenny Diski was dying. It was 10:07 a.m. on April 25; I Googled to make sure, before I filed this review, that she was still alive. She was. Her “onc doc” gave her a year in April 2015, which meant, if she survived another seven days, she would technically beat the projections. She did not. She died on the morning of April 28, 2016.

Diski, as she makes vitally clear in her new memoir, “In Gratitude,” spent her every moment on earth beating the projections of authority figures. She overcame abusive and neglectful parents, foster homes, suicide attempts, repeated hospitalizations and the persistently gloomy conviction of relatives, caregivers, teachers, doctors and occasionally herself that she would fail at whatever she attempted.

Diski did not fail. Over the past 30 years, Diski published 17 books of fiction and nonfiction and became a writer who commanded descriptions from reviewers like “individual” and “wildly various”; her books — such as her 1997 “so-called travel book,” “Skating to Antarctica” (which she described as being about “Icebergs, mothers. That sort of thing”) — all proof, as Giles Harvey wrote in a 2015 New York Times Magazine profile, of her “spectacular originality.”

In September 2014, two months after the diagnosis, Diski began publishing essays in The London Review of Books about her illness and impending death.

more here.

taking stock of Karl Ove Knausgaaard

My-struggle-book-fiveScott Esposito at The Quarterly Conversation:

Respected, parodied, revered, despised, Karl Ove Knausgaard’s My Struggle has been with us for just four years. Few in the English-speaking world knew the Norwegian’s name in 2012, but in just four years he has come to seem so omnipresent that NYRB critic, author, and beloved contrarian Tim Parks recently chastised us against “the impression of [Knausgaard's] huge and inevitable success.”

There is some truth there. He has not sold in numbers that would put envy on J.K. Rowling’s face—there is a degree of hype—but with U.S. sales of the first four volumes of the series likely topping 200,000 copies, Knausgaard is certainly far more successful and better-known than all but a handful of authors of the last few years. And now that we have Book 5 the end is in sight; the method behind the entire cycle has at last come into view. It is time to take stock.

At the start few would have predicted Knausgaard’s extraordinary success, but there were signs. James Wood rhapsodized Book 1 in The New Yorker in one of his best reviews of 2012, drawing on a beloved Walter Benjamin essay to examine Knausgaard’s fascination with death. In support of that first book Knausgaard gave well-attended events in New York City, and he received a lengthy profile by The New York Times. Surely if you swing a cat in many metropolitan areas it will collide with a few authors who have attained similar notoriety; still, it was a promising beginning.

more here.

Eric Hobsbawm on Latin America

A1kzaQ0nPBLJohn Paul Rathbone at the Financial Times:

Ten years before he died in 2012, the great British historian Eric Hobsbawm wrote that the only region outside Europe which he thought he knew well and where he felt entirely at home was Latin America. “Nobody who discovers South America can resist the region,” he wrote in his autobiography Interesting Times.

There was the persistent fascination of a continent that is a “laboratory of historical change … made to undermine conventional truths”. It was fun, too: Hobsbawm admits that he did “not even try to resist the sheer drama and colour of the more glamorous parts of that continent”. Because of its European linguistic and cultural overlays, Latin America was also accessible, with “an unexpected air of familiarity, like the wild strawberries to be found on the path behind Machu Picchu”.

Hobsbawm first visited the region in 1960 and was soon “permanently converted”. So began a 40-year intellectual engagement that is of particular interest today, as it illuminates Latin America’s apparent swing away from the political left and away from the revolutionary changes that Hobsbawm, a Marxist, hoped to see.

As a card-carrying Communist, Hobsbawm’s interest in Latin America was first piqued and then sustained by its potential for revolution. There was the “endearing” early promise of Fidel Castro’s triumph in January 1959. More importantly, beyond Cuba there was “a continent apparently bubbling with the lava of social revolutions” — first in Peru and Colombia, then in Chile, later in Central America and Venezuela, and finally Brazil.

more here.

Flora, fauna and fraud: cheats of the natural world – in pictures

Martin Stevens in The Guardian:

PlantCarnivorous plants trap and capture animals, especially arthropods, to acquire extra nutrients. They have many tricks to do this, including mimicking the smells of things that insects are often attracted to, such as rotting vegetation. In some pitcher plants, the rims of the pitchers glow under ultraviolet light (which is common under normal daylight). The rims absorb ultraviolet wavelengths and re-emit the light at longer ‘blue’ parts of the spectrum. Just like the brightly coloured spider sitting on a web, this attracts insects, luring them to their death.

More here.

Think Less, Think Better

Moshe Bar in The New York Times:

MindA FRIEND of mine has a bad habit of narrating his experiences as they are taking place. I tease him for being a bystander in his own life. To be fair, we all fail to experience life to the fullest. Typically, our minds are too occupied with thoughts to allow complete immersion even in what is right in front of us. Sometimes, this is O.K. I am happy not to remember passing a long stretch of my daily commute because my mind has wandered and my morning drive can be done on autopilot. But I do not want to disappear from too much of life. Too often we eat meals without tasting them, look at something beautiful without seeing it. An entire exchange with my daughter (please forgive me) can take place without my being there at all. Recently, I discovered how much we overlook, not just about the world, but also about the full potential of our inner life, when our mind is cluttered. In a study published in this month’s Psychological Science, the graduate student Shira Baror and I demonstrate that the capacity for original and creative thinking is markedly stymied by stray thoughts, obsessive ruminations and other forms of “mental load.” Many psychologists assume that the mind, left to its own devices, is inclined to follow a well-worn path of familiar associations. But our findings suggest that innovative thinking, not routine ideation, is our default cognitive mode when our minds are clear.

In a series of experiments, we gave participants a free-association task while simultaneously taxing their mental capacity to different degrees. In one experiment, for example, we asked half the participants to keep in mind a string of seven digits, and the other half to remember just two digits. While the participants maintained these strings in working memory, they were given a word (e.g., shoe) and asked to respond as quickly as possible with the first word that came to mind (e.g., sock). We found that a high mental load consistently diminished the originality and creativity of the response: Participants with seven digits to recall resorted to the most statistically common responses (e.g., white/black), whereas participants with two digits gave less typical, more varied pairings (e.g., white/cloud).

More here.

Friday, June 17, 2016

How should we treat science’s growing pains?

Jerome Ravetz in The Guardian:

ScreenHunter_2039 Jun. 17 15.33As noted already in the Guardian’s science pages, there is no lack of initiatives to tackle science’s crisis in all its aspects, from reproducibilityto the abuse of metrics, to the problems of peer review. This gives good grounds for hope that the crisis will eventually be resolved, and that it will not become a general crisis of trust in science. Should that occur, and ‘science’ ceases to be a key cultural symbol of both truth and probity, along with material beneficence, then the consequences could be far-reaching. To that end, we should consider what lies behind the malpractices whose exposure has triggered the crisis over the last decade.

It is clear that a combination of circumstances can go far to explain what has gone wrong. Systems of controls and rewards that had evolved under earlier conditions have in many ways become counterproductive, producing perverse incentives that become increasingly difficult for scientists to withstand. Our present problems can be explained partly by the transformation from the ‘little science’ of the past to the ‘big science’ or ‘industrialised science’ of the present. But this explanation raises a problem: if the corrupting pressures are the result of the structural conditions of contemporary science, can they be nullified in the absence of a significant change in those conditions?

More here.

The Neutral Theory of Evolution

Chase Nelson in Inference:

ScreenHunter_2038 Jun. 17 15.30Originally proposed by Motoo Kimura, Jack King, and Thomas Jukes, the neutral theory of molecular evolution is inherently non-Darwinian.2 Darwinism asserts that natural selection is the driving force of evolutionary change. It is the claim of the neutral theory, on the other hand, that the majority of evolutionary change is due to chance.

Each individual in a typical mammal population has two copies of its genome in almost every cell. The exact DNA sequences they contain may differ as the result of mutations, random copying errors in which one nucleotide letter is replaced by another. Other changes can also occur, such as the deletion or duplication of larger DNA segments. The result is genetic variation, and it is estimated that, for human beings, each child acquires 100 new mutations—50 in each genome copy—that were not present in its parents’ DNA.3 Genetic variation means no more than spelling differences in the DNA sequences carried by different individuals in a population. When a new DNA spelling is generated, an allele is born. This alternative form of the original gene may or may not lead to changes in the organism’s physical characteristics.

Evolution involves the substitution of one allele for another in a population. Having come about by chance, a new allele becomes increasingly common, and finally replaces the old allele. An evolutionary substitution has occurred.

More here.

 Through their editorial work on the writings of Walter Benjamin, Theodor Adorno and Gershom Scholem forged an unlikely friendship

Peter E. Gordon in The Nation:

ScreenHunter_2037 Jun. 17 15.22In February 1966, the historian Gershom Scholem dashed off a few lines to alert his friend Theodor Adorno of his travel plans. “I’ll arrive Wednesday in Frankfurt, where I’ll touch down at the Park Hotel,” he wrote. “Please arrange with the Marxist heavens, just in case you don’t maintain diplomatic relations with the resident of the other heaven, for sunshine on March 16th. For myself I prefer to rely on the old angel.”

The collected correspondence between Scholem and Adorno, recently issued by the prestigious German publishing house Suhrkamp Verlag, doesn’t record the meteorological conditions for the middle of March 1966. Nor do we know whose deity might have proved more responsive. Men of extraordinary erudition and critical acumen, Scholem and Adorno could never truly overcome their philosophical and political differences, though in retrospect it’s clear that both men epitomized a shared style of Central European intelligence, fusing irony with utopian conviction, that emerged in the years before the mid-century catastrophe.

Born in 1897, Gershom (originally Gerhard) Scholem was raised in a well-acculturated German-Jewish family in Berlin. Early in life, he committed himself to the Zionist cause, and by 1923 he’d immigrated to Palestine, where he assumed a post at the newly established Hebrew University of Jerusalem and forged an entirely new field of historical inquiry into the esoteric and half-forgotten texts of the Kabbalah. Theodor Ludwig Wiesengrund-Adorno was born in 1903 (the “Adorno” is from his mother’s Catholic Corsican side) and was raised in Frankfurt, where he divided his time between philosophy and music. Eventually, he would join intellectuals like Max Horkheimer, Herbert Marcuse, and Leo Löwenthal to develop the subtle style of neo-Marxist social philosophy known as “critical theory.” The two wouldn’t meet in person until 1938, at the New York home of the socialist theologian Paul Tillich, who had once served as Adorno’s academic adviser.

More here.

The Unbelievable Tale of Jesus’s Wife

1e1c2a3a3Ariel Sabar at The Atlantic:

On a humid afternoon this past November, I pulled off Interstate 75 into a stretch of Florida pine forest tangled with runaway vines. My GPS was homing in on the house of a man I thought might hold the master key to one of the strangest scholarly mysteries in recent decades: a 1,300-year-old scrap of papyrus that bore the phrase “Jesus said to them, My wife.” The fragment, written in the ancient language of Coptic, had set off shock waves when an eminent Harvard historian of early Christianity, Karen L. King, presented it in September 2012 at a conference in Rome.

Never before had an ancient manuscript alluded to Jesus’s being married. The papyrus’s lines were incomplete, but they seemed to describe a dialogue between Jesus and the apostles over whether his “wife”—possibly Mary Magdalene—was “worthy” of discipleship. Its main point, King argued, was that “women who are wives and mothers can be Jesus’s disciples.” She thought the passage likely figured into ancient debates over whether “marriage or celibacy [was] the ideal mode of Christian life” and, ultimately, whether a person could be both sexual and holy.

King called the business-card-size papyrus “The Gospel of Jesus’s Wife.” But even without that provocative title, it would have shaken the world of biblical scholarship. Centuries of Christian tradition are bound up in whether the scrap is authentic or, as a growing group of scholars contends, an outrageous modern fake: Jesus’s bachelorhood helps form the basis for priestly celibacy, and his all-male cast of apostles has long been cited to justify limits on women’s religious leadership.

more here.