The Strange Similarity of Neuron and Galaxy Networks



Your life’s memories could, in principle, be stored in the universe’s structure.

Christof Koch, a leading researcher on consciousness and the human brain, has famously called the brain “the most complex object in the known universe.” It’s not hard to see why this might be true. With a hundred billion neurons and a hundred trillion connections, the brain is a dizzyingly complex object.

But there are plenty of other complicated objects in the universe. For example, galaxies can group into enormous structures (called clusters, superclusters, and filaments) that stretch for hundreds of millions of light-years. The boundary between these structures and neighboring stretches of empty space called cosmic voids can be extremely complex.1 Gravity accelerates matter at these boundaries to speeds of thousands of kilometers per second, creating shock waves and turbulence in intergalactic gases. We have predicted that the void-filament boundary is one of the most complex volumes of the universe, as measured by the number of bits of information it takes to describe it.

This got us to thinking: Is it more complex than the brain?

So we—an astrophysicist and a neuroscientist—joined forces to quantitatively compare the complexity of galaxy networks and neuronal networks. The first results from our comparison are truly surprising: Not only are the complexities of the brain and cosmic web actually similar, but so are their structures. The universe may be self-similar across scales that differ in size by a factor of a billion billion billion.

The task of comparing brains and clusters of galaxies is a difficult one. For one thing it requires dealing with data obtained in drastically different ways: telescopes and numerical simulations on the one hand, electron microscopy, immunohistochemistry, and functional magnetic resonance on the other.

It also requires us to consider enormously different scales: The entirety of the cosmic web—the large-scale structure traced out by all of the universe’s galaxies—extends over at least a few tens of billions of light-years. This is 27 orders of magnitude larger than the human brain. Plus, one of these galaxies is home to billions of actual brains. If the cosmic web is at least as complex as any of its constituent parts, we might naively conclude that it must be at least as complex as the brain.

The total number of neurons in the human brain falls in the same ballpark of the number of galaxies in the observable universe.

But the concept of emergence makes the comparison possible. Many natural phenomena are not equally complex at all scales. The majestic network of the cosmic web becomes evident only when the sky is surveyed over its largest extent. On smaller scales, with matter locked into stars, planets, and (probably) dark matter clouds, this structure is lost. An evolving galaxy does not care about the dance of electron orbitals within atoms, and electrons move around their nuclei without regard to the galactic system they reside in.

In this way, the universe contains many systems nested into systems, with little to no interaction across different scales. This scale segregation allows us to study physical phenomena as they emerge at their own natural scales.

The building blocks of the cosmic web are the self-gravitating halos of stars, gas, and dark matter (whose existence has yet to be definitively proved). In total, the number of galaxies within the observable universe should be on the order of 100 billion. The balance between the accelerating expansion of the fabric of spacetime and the pull of self-gravity gives this network its spider-web-like pattern. Ordinary and dark matter condense into string-like filaments, and clusters of galaxies form at filament intersections, leaving most of the remaining volume basically empty. The resulting structure looks vaguely biological.

A direct estimate of the number of cells or neurons in the human brain was not available in the literature until recently. Cortical gray matter (representing over 80 percent of brain mass) contains about 6 billions neurons (19 percent of brain neurons) and nearly 9 billion non-neuronal cells. The cerebellum has about 69 billion neurons (80.2 percent of brain neurons) and about 16 billion non-neuronal cells. Interestingly enough, the total number of neurons in the human brain falls in the same ballpark of the number of galaxies in the observable universe.



Why Men Say They’ve Had More Sex Partners Than Women

It’s not just because they multiply by 3

by Tracy Moore

If you’ve read any sex surveys pretty much anywhere ever in your life, you’ve learned a curious truth: Heterosexual men, on average, have more sexual partners than heterosexual women do. Sometimes it’s two or four times or more, with one study finding men have an average of seven partners to women’s four, and another showing that men had roughly 13 partners on average to women’s 7. Mathematicians protest that this is logically impossible — it takes two people to have sex, after all, so the median number of partners should be the same for men and women.

So what’s with the funny math?

Turns out there are a lot of reasons the numbers can get skewed, and they don’t all involve lying.


Of course, lying is still typically the most frequently cited reason for skewed results. Men tend to inflate their numbers, researchers say, whereas women lowball. The reasons are fairly obvious if we go by broad cultural stereotypes about promiscuity and gender: Men are supposed to go out there and get all they can while they can; women are supposed to seem discerning about who they let get up in there. Women are supposed to guard their virginity for love; men are supposed to get it over with as soon as possible or risk eternal humiliation. It follows then, that women would feel pressured to still seem pure, while men would feel pressured to seem experienced.

American Pie 2 gave us a solid bullshit detection formula for deciphering how many sex partners men and women really have, though. It’s called the rule of three — men should multiply the number of partners a woman claims to have had by three to get an accurate number; women should divide the number of partners a man claims to have had by three to get the real answer.

While that’s got to be an exaggeration, the takeaway here is that men round up; women round down.

Counting Strategies

That said, there’s some evidence maybe men and women aren’t lying but counting the number of people they’ve slept with differently, according to Bradley University psychology professor David Schmitt. “When asked about one’s number of past sex partners, women tend to recall each and every past partner individually (Bill, Ted, Tony, Tim…), whereas men tend to ‘guesstimate’ using large round numbers (around 10),” Schmitt writes at Psychology Today.

The key point here, though, is that both methods are flawed. Researchers say the “raw count” women use results in deflated numbers. “They tend to say, ‘I just know,’ and if you ask them to explain how they know, they say, ‘Well, there was John, Tom, etc.,’” psychologist Norman Brown, who studies flaws in self-reported sex surveys, told Live Science. On the other hand, the rough approximation men use leads to inflated numbers. “Men are twice as likely to use rough approximation to answer the question,” Brown told them. “And rough approximation is a strategy known to produce over-estimation.”


The older you get—and maybe the more people you’ve slept with—the less likely you are to remember exactly how many times you got it on. Some people, at some point, literally just stop counting, as evidenced by this quote from Christine, 35, who told the New York Daily News exactly that about her sex life in 2008.

“I stopped counting at 56,” said Christine, 35, a locations director from Baysidewho lives in SoHo. “There are so many opportunities to meet men here — bars, restaurants, clubs, walking down the street, the deli. Men are everywhere.”

The Prostitute Effect

If men are more likely to pay for sex here or abroad than women — research Schmitt cites found that 15 percent of American men do, compared to fewer than 1 percent of American women (again, assuming they are telling the truth) — men may count those extra experiences in their tally.

However, other experts argue this can’t adequately account for the difference. “Invoking women who are outside the survey population cannot begin to explain a difference of 75 percent in the number of partners, as occurred in the study saying men had seven partners and women four,” University of California, Berkeley, mathematics professor David Gale, told The New York Times.

What Counts as Sex

Perhaps most interesting of all the reasons these studies might skew higher for men is that, eager to keep that number up, men may toss in nearly anything remotely sexual as a sex act in their tally. According to Schmitt over at Psychology Today, men count more sexual interactions as sex than women do. “Because men consider more sexual behaviors to count as sex than women (e.g., oral sex, intimate massages), this might lead men to report, on average, higher numbers of past sex partners than women do,” he writes.

This is very confusing. Is sex (between heterosexuals) not exclusively penis-in-vagina? A blowjob is certainly a sexual act but it’s not intercourse, though it’s not out of the realm of possibility to include it as part of a tally. But going down on a woman could be sex if you’re a lesbian — one lesbian on a forum asking what constitutes sex said she considers oral and fingering sex between women, but only third base or foreplay between men and women…



The Atreides vs the Ancient Greeks

Clytemnestra just murdered Agamemnon

I’d been reading a book by Colm Tóibín called House of Names.  The house is the House of Atreus; Tóibín explained through a character why he substituted “names,” but I didn’t understand it.  He took the story pretty faithfully from the plays of Sophocles, Aeschylus, and Euripedes about one or all members of the family.  The family was dreadful, every one of them, and Tóibín made each individual dreadfulness understandable, as did the original Greek playwrights.  The family is soaked in its own blood, generation after generation; crime begets murder which bets revenge killing and more revenge killing and revenge killing that never stops. The translator of the Greek plays, Robert Fagles, calls it an “inherited infection.”

Somewhere in the middle, I started to wonder about the strange discrepancy between these revenge-addled murderers and the rational, educated ancient Greeks who were the foundation of Western civilization; who founded much of our sculpture, architecture, philosophy, literature, math, and science; and who told these terrible stories over and over.

Electra and Orestes

You probably know the story of the House of Atreus but I’ll tell you again anyway.  The story begins with meddling gods — who are, compared to the humans, unconvincing and uninteresting,Tóibín leaves them out completely and I will too – and moves on to misbehaving humans who are clearly cursed, whose blood is made of desire for love and power and revenge, and because the desire is in the blood, it’s inexorable.

Atreus had a brother named Thyestes who was sleeping with Atreus’s wife. Atreus killed Thyestes’ children, cooked them, and served them to Thyestes.  Thyestes had another son, Aegisthus, who grew up to sleep with Clytemnestra, the wife of Atreus’s son, Agamemnon.  Agamemnon for one reason or another – maybe because his navy was becalmed and the gods needed a sacrifice before they’d send wind – sacrificed Iphigenia, his daughter with Clytemnestra.  Clytemnestra, with Aegisthus’s help, murdered Agamemnon.  Agamemenon and Clytemestra’s son, Iphigenia’s brother, Orestes, at the urging of his other sister, Electra, murdered Clytemnestra. Toíbín ends his book with Orestes agreeing to give up his claim to kingship and live out his life in quiet domesticity

What to make of this?  An eye for an eye, kill and be killed.  It’s thoroughly human, it’s certainly not civilized, and the Greeks who wrote and watched these plays were nothing if not civilized.  But a lot of their plays have the same story: someone does something wrong, someone gets revenge, the children inherit the wrong and avenge the revenge, and so do their own children.  I can think of a couple of reasons for this.

One is that it’s true.  We call it different things today – genetics, environmental influences, sociological tribalism — but it still plays out not only obviously in organized crime and the murder code of the inner cities, but also in every division we’ve got: religious, political, economic, cultural, educational.  It’s what we do. We live in families, and that’s the source of both our loveliest virtues and our most shameful vices.

Another is that the stories are of people and acts so terrible that nothing good can come of them.  That’s so obvious.  Nobody’s going to live happily ever after here, not Agamemnon, not Clytemnestra, not Electra and Orestes.  In Aeschylus’s play, Orestes leaves his home, hounded by the Furies, and wanders frightened and guilty until the gods and the Furies hold a trial to balance justice with revenge.  Orestes is freed from the Furies, but nobody’s forgetting his mother’s death,

Fagles makes a lot of this balance between the gods and the Furies, and of Aeschylus’s real ending, which turns the Furies, the Erinyes, into the Eumenides, the Good Ones.  (I find Fagles a little hard to follow, though his translations are vivid.)  But maybe the ancient Greeks told these stories as a way for intelligent, perceptive, civilized people to remember the lethality of their heritage, to not forget that the alternative to law and rationality is real, alive, and always present.


Illustrations from Alfred Church, Stories from the Greek Tragedians, 1897, via Project Gutenberg and Wikimedia Commons


How to Get Rid of Pests and Bugs the Buddhist Way

How to Get Rid of Pests and Bugs the Buddhist Way
Photo by Kate Brady

Kill that impulse! Here are compassionate Buddhist solutions for your favorite pests, without killing them.

By Allan Badiner
Good news and bad news. The bad news first: No, you do not have special dispensation from the Buddha to murder those obnoxious little rodent and insect pests that are somehow capable of terrorizing beings thousands of times their size, when all they want is a little food, water and a place to get cozy up with their mates.
The good news is that with a little extra effort, you can rid yourself of these unwelcome guests (ants, mice, cockroaches, fleas, ticks, etc) and feel the karmic joy of living in the light of the dharma!

“Dharma” means truth and the teachings, and it is also the word for nature itself.  The Venerable Narada Mahathera tells us that as nature is the manifestation of truth, and of the teachings, we should cultivate kindness and compassion for all, trying not to kill or cause injury to any living creature, even the tiniest creature that crawls at our feet, and bites them.

Of course precepts, or guidelines for following the dharma, are training principles, and Buddhists undertake to observe them to the best of their abilities.  At times certain conditions may not allow us to rigidly adhere to the precepts and no one can live through life without ever breaking them.  It is at such times that we must use our common sense and human intelligence to make the best decisions.

In Buddhism there is a long held and integral tradition of caring for animals and all living creatures. They are regarded in Buddhist thought as sentient beings, different than humans in their intellectual ability but no less capable of feeling suffering, fearing death, and craving life. Vasubandhu, a 4th century Indian scholar-monk and one of the most prominent figures in Buddhist history, said that it is deluded to kill even poisonous pests, and Asoka, the Buddhist King of India, posted edicts that included a prohibition on the killing of vermin of all kinds.

At the time of the Buddha, rules were made against monks wandering about in the rainy season in part due to the damage done to so many creatures rising to the surface of wet soil for a drink. The same applied to the cutting of trees that were seen as essential to the lives of many animals large and small (known as “breathers”). Asoka planted shade trees, medicinal herbs and wayside wells for both humans and animals. This culture of non-harming, and recognition of the right to life enjoyed by all sentient beings contributes to what makes a monastery or Buddhist temple feel so safe and welcoming to all.

Robert Thurman tells of the great India scholar-monk Asanga from the 5th century CE who at that point, had been meditating in a cave for 12 years, unsuccessfully, in order to gain a vision of the Bodhisattva Maitreya, the future Buddha and the embodiment of loving kindness.  One day he saw a stray dog afflicted with maggot infested sores. Fearing that pulling the maggots off the dog would harm them, he expended great effort to coax them off the sore and onto his warm and moist tongue where they could feed on his own flesh.  At this point, both the dog and the maggots disappeared, and a full and splendorous image of Maitreya appeared where the dog had once been.

Meanwhile, just by walking in the forest or breathing the air, we are taking the life of many small creatures. We inadvertently kill hundreds of insects on a nighttime car ride. We wipe out thousands of bacteria, also sentient beings, daily when we shower and brush our teeth and disinfect our homes.  Generally, there has been a strong element of practicality in Buddhism relative to the extent people are expected to go to avoid any and all killing.

This is one way that the Middle Path distinguished itself from Jainism, where the most devoted of followers would shun clothing, wear masks to filter out airborne creatures, and sweep their path before letting their feet touch the ground. The Buddhist approach to ahimsa, or non-harming, in the realm of small animals and microorganisms, was to exercise all reasonable measures to avoid needless or avoidable killing—recognizing that these creatures too want to eat and avoid harm. In fact, humans are not apart from the world of microorganisms, and are made up of many smaller beings living on us and within us.

Nevertheless, as Buddhist scholar Brian Peter Harvey explains, to kill or harm another being, whether it is a rat or a cockroach or a horse, is to ignore the fragility and aspiration for happiness that one has in common with it. This violates the dharma of interdependence, and compassion. The Buddha made no distinction between the sizes of the victim (cow or ant) or between intentions in killing (self-defense or hunting for pleasure). However, Buddhism focuses heavily on intention, so that all acts of killing are not necessarily equally blameworthy. However, its stronger emphasis on compassion insures that not harming other beings is always praiseworthy…



A Pioneering Scientist on Memory, the Value of Our Unremembered Work, and the Incalculable Sum Total of the Human Experience

Illustration from The Book of Memory Gaps by Cecilia Ruiz

“Are we not … parts of a greater organism, kept alive through the ever more vividly circulating blood of an enormous past?”

“Life is not what one lived, but what one remembers and how one remembers it in order to recount it,” Gabriel García Márquez asserted in immortalizing the memory of his own life. And yet however much truth the sentiment may hold, it holds twice as much tragedy — although memory is the seedbed of our sense of self, the vast majority of life unfolds in the small, unremembered moments that furnish the microscopic threads in the tapestry of being. Sally Mann captured this paradox in her exquisite meditation on the dark side of memory“The exercise of our memory does not bring us closer to the past but draws us farther away.”

Memory, then, is not the pencil with which the outline of a life is drawn but the eraser — something as true of our personal memory as it is of our collective memory, which contains everything we know as culture: the great works of art celebrated generations after their creators have returned to stardust, the scientific discoveries that become the building blocks of subsequent theories and breakthroughs.

Perhaps because science is the ultimate self-correcting mechanism and necessarily builds on both the errors and the triumphs of the past, scientists must have a particularly revealing perspective on memory and its paradoxes. That’s what pioneering biochemist Erwin Chargaff (August 11, 1905–June 20, 2002) explores in a passage of Heraclitean Fire: Sketches from a Life Before Nature — his uncommonly lyrical memoir, which gave us Chargaff on the poetics of curiosity and the power of being an outsider.

Erwin Chargaff

Chargaff writes:

If we could not forget, we could not remember; just as only the trembling balance can weigh. There are nights with a rose tint, there are days black with clouds, a groan from a deathbed, a hand on my hair, a voice out of the pyre of forgottenness. The ashes do speak, but it is a broken murmur. Brief reflections of brightness, as from a shattered mirror, play over the blackness of an ever-present past.

I tell what I am told. Who is the speaker? If it is memory, then why does it sometimes whisper, sometimes shout, often chatter, and mostly remain in sullen silence?

Noting that this nature of memory condemns him to “writing as a fragmentist,” Chargaff looks back on his own past as a scientist and reflects on the “ghostly pantomime” in which scientists engage as they test theories and perform experiments invisible to the outside world, lost to the canon of collective memory, which James Gleick once so elegantly termed “the fast-expanding tapestry of interwoven ideas and facts that we call our culture.” With an eye to his days in the laboratories of Columbia University and their invisibilia of forgotten yet undismissable work, Chargaff writes:

That most of this activity did not lead to anything handed on to posterity was perhaps a pity. But does this count in the face of a human life? Does not the great corpus mysticum of the world contain all that was once felt or thought, suffered or overcome, created or forgotten, whether written or unwritten, made or destroyed? Are we not in this sense parts of a greater organism, kept alive through the ever more vividly circulating blood of an enormous past?


The pig on your plate

Resultado de imagem para Limousin sow, Dordogne de Neuvialle (two years old), and her piglet. Photo by Yann Arthus-Bertrand/Getty

Limousin sow, Dordogne de Neuvialle (two years old), and her piglet. Photo by Yann Arthus-Bertrand/Getty

That pigs are smart and sensitive is not in doubt. How can we justify continuing to kill them for food?

by Barbara J King is emerita professor of anthropology at the College of William and Mary in Williamsburg, Virginia. She writes for NPR’s 13.7 Cosmos and Culture blog and her latest books are Personalities on the Plate: The Lives and Minds of Animals We Eat (2017) and How Animals Grieve (2013).

Domestic pigs, the kind portrayed in hot-pink neon above barbecue joints, curly tailed and carefree, have prodigious memories. In problem-solving with computers, they match wits with little kids and win. They are able to plan ahead, and they live in complex social communities. They recognise other pigs as distinct individuals.

Pigs aren’t just cerebral, though: they have heart. When others are in distress, they can express concern and act with empathy. A description of pig behaviours, derived from scientific experiments and compiled by Lori Marino of the Kimmela Center for Animal Advocacy and Christina M Colvin at Georgia Institute of Technology is so impressive, you might think it was about chimpanzees, elephants or whales.

We eat pigs, though, and we eat them on a scale unparalleled in comparison with the rate at which we consume other brainy mammals. According to the United Nation’s Food and Agriculture Organization, pork is the most consumed meat in the world.

Barbecue is a cultural obsession in many countries, as is bacon, whether served straight up or in more recent innovations such as bacon chocolate and bacon vodka. Plus, once satiated with real bacon, some might even retire to bed after brushing with bacon-flavoured toothpaste.

We value the taste of pigs far more than we value the lives of pigs. Exceptions include pig celebrities, whose personalities are known and cherished, and whom we assign to a different, protected, pet-like non-consumable status. Esther, a 650 lb ‘wonder pig’ who lives in a house with Derek Walter and Steve Jenkins in Ontario, Canada, is a ‘public figure’ on Facebook with more than 1.1 million followers.

Or consider Christopher Hogwood (named after the famed English conductor and musicologist), a pig who lived in a barn at the home of Sy Montgomery and Howard Mansfield in New Hampshire from his infancy until his death at age 14. Christopher grew to a size even larger than Esther, and through Montgomery’s memoir The Good Good Pig(2006) became a poster pig for porcine cognition and emotion.

Montgomery describes how a belly rub in the sun from her, or dinner leftovers from a local chef, plunged Christopher into a state of utter delight visible to all: he telegraphed this rapture through sound (‘unh-unh-unh!’) and body posture. At those moments, he became the ultimate mindful mammal, one who dwelled entirely in the present. But Christopher didn’t live only in the present any more than we do. He built nests, not in a rote instinctual way, but in fussy anticipation of his own needs for soft-hay comfort. His memory for individual humans – his own complex social community – was excellent. Two young children, once neighbours, continued to visit him at irregular intervals even after they moved to another state. ‘He still remembered the little girls next door,’ Montgomery told me, ‘when they had been away not only for a pretty long time, but during a period of adolescent growth in which just a few months will make a big difference – in what you look like, how tall you are, what your voice sounds like, what you smell like.’ Christopher’s ‘voice became softer and lower’ when interacting with people who were visibly sad, a feat of perspective-taking that suggests an empathy response.

Of course, storytelling about pigs as individuals invites people to think differently about pork and bacon. But what does science – the kind of science reviewed by Marino and Colvin – say? That question has preoccupied me for several years.

Some science begins with the presumption that pigs are not particularly intelligent or empathetic animals. Two years ago, a group of swine researchers led by the animal scientist Sophie Brajon then at the Université Laval in Quebec published the paper ‘The Way Humans Behave Modulates the Emotional State of Piglets’. The research is part of a corpus showing that the emotional state of animals, including farmed animals, biases their information-processing. Yet the conclusion reached, that gently handled pigs showed more positive emotional states than roughly handled or neglected ones, conveys a larger message. We have a way to go before that message is accepted, as opposed to the big argument, that farmed animals have emotions and are affected by how we treat them.

A good deal of the science writing on pigs aims to increase awareness of pigs’ capacities so that they are treated better. The biologist Donald Broom and colleagues at the University of Cambridge discovered that pigs, with only five hours of experience, can use a mirror to find the location of a hidden object. Mirror-naïve pigs search behind the mirror to find the treat, but after five hours’ practice, 10 of 11 pigs turned away to find the real location of the savoury items within 23 seconds. (A fan blew the food smells away, so that smell cues didn’t confound the process.) This is a cognitive feat because both the concept of the food and its position must be remembered, as interpreted from the non-real-world view of the mirror…


%d bloggers like this: