Introducing ‘dark DNA’ – the phenomenon that could change how we think about evolution

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By Adam Hargreaves, University of Oxford

DNA sequencing technology is helping scientists unravel questions that humans have been asking about animals for centuries. By mapping out animal genomes, we now have a better idea of how the giraffe got its huge neck and why snakes are so long. Genome sequencing allows us to compare and contrast the DNA of different animals and work out how they evolved in their own unique ways.

But in some cases we’re faced with a mystery. Some animal genomes seem to be missing certain genes, ones that appear in other similar species and must be present to keep the animals alive. These apparently missing genes have been dubbed “dark DNA”. And its existence could change the way we think about evolution.

My colleagues and I first encountered this phenomenon when sequencing the genome of the sand rat (Psammomys obesus), a species of gerbil that lives in deserts. In particular we wanted to study the gerbil’s genes related to the production of insulin, to understand why this animal is particularly susceptible to type 2 diabetes.

But when we looked for a gene called Pdx1 that controls the secretion of insulin, we found it was missing, as were 87 other genes surrounding it. Some of these missing genes, including Pdx1, are essential and without them an animal cannot survive. So where are they?

The first clue was that, in several of the sand rat’s body tissues, we found the chemical products that the instructions from the “missing” genes would create. This would only be possible if the genes were present somewhere in the genome, indicating that they weren’t really missing but just hidden.

[Read more…]


Why have we taken so long to catch up with animal consciousness?

Brandon Keim writes: I met my first semipalmated sandpiper in a crook of Jamaica Bay, an overlooked shore strewn with broken bottles and religious offerings at the edge of New York City. I didn’t know what it was called, this small, dun-and-white bird running the flats like a wind-up toy, stopping to peck mud and racing to join another bird like itself, and then more. Soon a flock formed, several hundred fast-trotting feeders that at some secret signal took flight, wheeling with the flashing synchronisation that researchers observing starlings have mathematically likened to avalanche formation and liquids turning to gas.

Entranced, I spent the afternoon watching them. The birds were too wary to approach, but if I stayed in one spot they would eventually come to me. They followed the tideline, retreating when waves arrived, and rushing forward as they receded, a strangely affecting parade. When they came very close, their soft, peeping vocalisations enveloped me. That night I looked at photographs I’d taken, marvelling as the birds’ beauty emerged from stillness and enlargement, each tiny feather on their backs a masterpiece of browns. I looked up their scientific classification, Calidris pusilla, conversationally known as the semipalmated sandpiper — a name derived from a combination of their piping signal calls and the partially webbed feet that keep them from sinking in the tidal sand flats of their habitat, where they eat molluscs, insect larvae and diatom algae growing in shallow, sun-heated seawater.

I learned that semipalmated sandpipers are the most common shorebird in North America, with an estimated population around 1.9 million. My copy of Lives of North American Birds (1996) described them as ‘small and plain in appearance’, which seemed unappreciative, especially in light of their migratory habits. Small enough to fit in my hand, they breed in the Arctic and winter on South America’s northern coasts, flying several thousand miles each spring and fall, stopping just once or twice. The flock I’d watched was a thread in a string of globe-encircling energy and life, fragile yet ancient, linking my afternoon to Suriname and the tundra. At that fact, I felt the sense of wonder and connection that all migratory birds inspire. Yet not once did I wonder what they thought and felt along the way. How did they experience their own lives, not just as members of a species, but as individuals? [Continue reading…]


The Anna Karenina hypothesis says that every unbalanced microbiome is unbalanced in its own way

Ed Yong writes: In 2012, Rebecca Vega Thurber looked at the results of the large underwater experiment she had been running for three years—and was disappointed.

Since 2009, her team had been traveling to the coral reefs of the Florida Keys. In some spots, they exposed the corals to nitrogen and phosphorus, to simulate the agricultural runoffs that often pollute these reefs. In other areas, they used wire mesh to keep fish away, mimicking the effects of overfishing. They wanted to know if these sources of stress disrupt the relationship between the corals and the trillions of microbes that live with them—and whether these disruptions lead to the corals’ demise.

Scientists have conducted hundreds of similar studies in humans. They compare healthy and sick people and look for differences in their microbiomes—the vast community of bacteria and other microbes that share our bodies. They aren’t looking for a specific disease-causing bug, like the ones behind classic infections like plague, leprosy, or tuberculosis. Instead, they’re looking for imbalances, where certain species rise to the fore, others slink into obscurity, and the entire community changes for the worse.

That’s what Vega Thurber expected to find in the corals. But that’s not what her postdoc Jesse Zaneveld found when he analyzed the results. The extra nutrients and the missing fish both changed the coral microbiomes—but not in any consistent ways. “It was a pretty dark day after three years of work,” says Vega Thurber. “A lot of students would have thrown up their hands and cried a bit. But Jesse said: You know what, I think I see something strange. It’s a pattern but one we didn’t predict.”

The microbiomes of the stressed corals had become more varied. They didn’t shift in any particular direction—they changed in every direction. And shortly after Zaneveld realized this, he spotted the same pattern—but this time in chimpanzees. Researchers at Yale University had studied the gut microbiomes of chimps that were infected with an HIV-like virus, and found that their microbiomes had also become more variable. [Continue reading…]


We can’t thrive in a world without darkness

Rebecca Boyle writes: Sound dominated my senses as we left the village of San Pedro de Atacama and walked into the desert night. The crunch of shoes on gravel underlay our voices, which were hushed to avoid waking any households or street dogs. Our small group of astronomy writers was escaping from light and, without any flashlights or streetlamps, we struggled to see, so our other senses were heightened. Land that looked red by day was now monochromatic, the rods in our retinas serving as our only visual input.

After about 15 minutes of hiking, we stopped to take some pictures of the sky. I fumbled with my gear and tried to get my bearings, but everything was alien. I was horribly jet-lagged after 10 hours hunched against the window of a 757, another two-hour flight north from Santiago and a two-hour bus ride, and it wan’t just my oxygen-hungry brain that put me out of sorts. The Atacama Desert looked like Mars as drawn by Dr Seuss; I was surrounded by wrong-coloured cliffs and swirling rock formations. But I was determined to photograph something even more bizarre: the Large Magellanic Cloud, a dwarf galaxy you can see only from the southern hemisphere. I perched my camera on a rock and aimed at the sky, but the cosmic smudge would not resolve in my viewfinder. I stood, brushed dirt from my jeans, and looked up.

The unfamiliar sky momentarily took away what little breath I had left at 8,000 feet in elevation. Above the horizon was the conspicuous Southern Cross. Orion was there, too, but looked as disoriented as I felt, upside down to the world. And there were so many constellations I’d never seen, with hopeful, Latinate names such as Dorado and Reticulum. Countless stars blazed into view as I stared into the smear of the Milky Way.

To most people who have travelled outside the developed world – whether to camp or to meditate or to hunt – such bright and plentiful stars are a glorious sight. But this beauty instilled in me a creeping sense of guilt. At home, 1,500 miles north, I wouldn’t recognise such spangled heavens. From where I live in the American Midwest, the stars might as well not exist. After journeying millions of years, their light is swallowed by city glare and my porch lantern. Those that make it through will still fail: not even bright Betelgeuse can outshine my iPhone. Yet I am an astronomy writer, a person who thinks about stars and planets all the time. What does my neglect of the night sky say about the rest of humanity?

‘We are all descended from astronomers,’ the astrophysicist Neil deGrasse Tyson intones in the rebooted version of the TV show Cosmos. This is as poetic as it is true. Everyone owns the night sky; it was the one natural realm all our ancestors could see and know intimately. No river, no grand mountain or canyon, not even the oceans can claim that. But since Edison’s light bulbs colonised our cities, the vast majority of humans has ceased to see those skies. More than 60 per cent of the world, and fully 99 per cent of the US and Europe, lives under a yellowy sky polluted with light. [Continue reading…]


Millennia ago, eclipses provided rare opportunities to measure the universe

Tyler Nordgren writes: As a kid visiting the Oregon coast I often wondered, “How wide is the ocean, and what is there beyond the horizon?” As I grew older and turned my sights to the night sky, I wondered something very similar: “How far away are the stars, and are there other planets there?” Even though very few of us have ever circumnavigated the globe, and no human being has ever ventured into space beyond the moon, we do know some of the answers to these questions. Immensity isn’t immeasurable. While these vast numbers may make little sense in our daily lives, we at least know they are known.

Consider what it must have been like to live in a world where this was not true: where the sense of immeasurability, the certainty of the unfathomable, was commonplace, and the thought that the world could be known was a novel idea. The philosopher Anaxagoras was born in about 500 B.C. in the eastern Mediterranean on what is now the coast of Turkey. It was a time when philosophy had only recently turned its attention to the natural world. Less than a hundred years before, Thales of Miletus supposedly predicted the solar eclipse that ended a war, thus implying that our world was predictable and events were not just the random whims of the gods.

In such a world of physical phenomena, Anaxagoras was the first, as far as we know, to understand that eclipses occur when one heavenly body blocks the light from another. This rejection of gods and dragons as the causes of eclipses was a revolutionary thought by itself, but Anaxagoras took it further: If solar eclipses happened only because the Earth had moved into the shadow of the moon, he reasoned, then the size of the shadow must tell us something about the size of the moon. Additionally, since the moon covered the sun, the sun must be farther away. Yet to appear nearly the same size, the sun must be larger than the moon. Herein lies the power of scientific thought: Measure the extent of the shadow sweeping across the Earth, and you know the moon must be at least as big as the shadow, and the sun larger still. Mysticism provided no such opportunity: If eclipses occur when a demon devours the sun, there is no reason to believe that any measurement we make here on Earth should reveal the demon’s size.[Continue reading…]


Beating the odds for lucky mutations

Jordana Cepelewicz writes: In 1944, a Columbia University doctoral student in genetics named Evelyn Witkin made a fortuitous mistake. During her first experiment in a laboratory at Cold Spring Harbor, in New York, she accidentally irradiated millions of E. coli with a lethal dose of ultraviolet light. When she returned the following day to check on the samples, they were all dead — except for one, in which four bacterial cells had survived and continued to grow. Somehow, those cells were resistant to UV radiation. To Witkin, it seemed like a remarkably lucky coincidence that any cells in the culture had emerged with precisely the mutation they needed to survive — so much so that she questioned whether it was a coincidence at all.

For the next two decades, Witkin sought to understand how and why these mutants had emerged. Her research led her to what is now known as the SOS response, a DNA repair mechanism that bacteria employ when their genomes are damaged, during which dozens of genes become active and the rate of mutation goes up. Those extra mutations are more often detrimental than beneficial, but they enable adaptations, such as the development of resistance to UV or antibiotics.

The question that has tormented some evolutionary biologists ever since is whether nature favored this arrangement. Is the upsurge in mutations merely a secondary consequence of a repair process inherently prone to error? Or, as some researchers claim, is the increase in the mutation rate itself an evolved adaptation, one that helps bacteria evolve advantageous traits more quickly in stressful environments?

The scientific challenge has not just been to demonstrate convincingly that harsh environments cause nonrandom mutations. It has also been to find a plausible mechanism consistent with the rest of molecular biology that could make lucky mutations more likely. Waves of studies in bacteria and more complex organisms have sought those answers for decades. [Continue reading…]


How color vision came to the animals

Nick Stockton writes: Animals are living color. Wasps buzz with painted warnings. Birds shimmer their iridescent desires. Fish hide from predators with body colors that dapple like light across a rippling pond. And all this color on all these creatures happened because other creatures could see it.

The natural world is so showy, it’s no wonder scientists have been fascinated with animal color for centuries. Even today, the questions how animals see, create, and use color are among the most compelling in biology.

Until the last few years, they were also at least partially unanswerable—because color researchers are only human, which means they can’t see the rich, vivid colors that other animals do. But now new technologies, like portable hyperspectral scanners and cameras small enough to fit on a bird’s head, are helping biologists see the unseen. And as described in a new Science paper, it’s a whole new world. [Continue reading…]


Is the living world more a result of happenstance or repeatable processes?

Zachary D Blount writes: Amazon’s television series The Man in the High Castle, based on the classic novel by Philip K. Dick, presents a nightmarish alternative 1962 in which the triumphant Nazi and Japanese empires occupy a fractured, defeated United States.

This alternate history is spun from the imagined consequences of a minor change in a real event. On February 15, 1933, Giuseppe Zangara opened fire on president-elect Franklin D. Roosevelt in Miami, Florida. Zangara was only 25 feet away, but his attempt failed because he shared the wobbly bench on which he stood with a woman who, as she strained to see, jostled the bench at just the right time to spoil his aim. The show’s version of history did not include the fortuitous jostle. Although the result of such a change might not have been the dystopia the show envisions, history would have been quite different had Roosevelt died that day.

Human history has been wrought from the particulars of unique events and personalities. Indeed, the historical record is rife with instances like the attempt on Roosevelt’s life, where even slight changes could have dramatically altered the course of events. These instances illustrate how the existence of the current world depended on the process of history, linking past to present in a complex web of causality. In other words, human history is contingent. Contingency, philosopher John Beatty has written, essentially means that history matters “when a particular future depends on a particular past that was not bound to happen, but did.” It arises because the future flows causally from the past, but many futures are possible at any given time, and which one comes to pass is determined by the precise, chance-laden way in which a complex tangle of improbable events interacting in improbable ways plays out. Contingency is why we can more or less explain the past, but the future is unpredictable. [Continue reading…]


Moon had a magnetic field for at least a billion years longer than thought

Science News reports: The moon had a magnetic field for at least 2 billion years, or maybe longer.

Analysis of a relatively young rock collected by Apollo astronauts reveals the moon had a weak magnetic field until 1 billion to 2.5 billion years ago, at least a billion years later than previous data showed. Extending this lifetime offers insights into how small bodies generate magnetic fields, researchers report August 9 in Science Advances. The result may also suggest how life could survive on tiny planets or moons.

“A magnetic field protects the atmosphere of a planet or moon, and the atmosphere protects the surface,” says study coauthor Sonia Tikoo, a planetary scientist at Rutgers University in New Brunswick, N.J. Together, the two protect the potential habitability of the planet or moon, possibly those far beyond our solar system.

The moon does not currently have a global magnetic field. Whether one ever existed was a question debated for decades (SN: 12/17/11, p. 17). On Earth, molten rock sloshes around the outer core of the planet over time, causing electrically conductive fluid moving inside to form a magnetic field. This setup is called a dynamo. At 1 percent of Earth’s mass, the moon would have cooled too quickly to generate a long-lived roiling interior.

Magnetized rocks brought back by Apollo astronauts, however, revealed that the moon must have had some magnetizing force. The rocks suggested that the magnetic field was strong at least 4.25 billion years ago, early on in the moon’s history, but then dwindled and maybe even got cut off about 3.1 billion years ago. [Continue reading…]


Are men seen as ‘more American’ than women?

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Protesters hold signs at the Chicago Women’s March in January 2017.
John W. Iwanski, CC BY-NC

By Laura Van Berkel, University of Cologne; Ludwin Molina, University of Kansas, and Sahana Mukherjee, Gettysburg College

Women make up 50.8 percent of the U.S. population and have equal voting rights, yet are politically underrepresented. The country has never had a female president or vice president. Only 3.5 percent of Supreme Court justices have been women, and women make up only 20 percent of Congress.

Studies have shown that within a country, groups with more power often feel greater ownership over it. Because they control actual resources, like money, and symbolic resources, like writing history, they’re better able to shape the culture in their image. For example, because Christianity is the most prominent religion in the United States, Christmas is a federal holiday.

Because men hold more power than women in the United States, we wanted to explore a simple question: Would people tend to think of men as “more American” than women? And, if so, how does this influence the way American women identify with their country?

[Read more…]


Here’s what the last common ancestor of apes and humans looked like

Charles Q. Choi writes: The most complete extinct-ape skull ever found reveals what the last common ancestor of all living apes and humans might have looked like, according to a new study.

The 13-million-year-old infant skull, which its discoverers nicknamed “Alesi,” was unearthed in Kenya in 2014. It likely belonged to a fruit-eating, slow-climbing primate that resembled a baby gibbon, the researchers said.

Among the living primates, humans are most closely related to the apes, which include the lesser apes (gibbons) and the great apes (chimpanzees, gorillas and orangutans). These so-called hominoids — that is, the gibbons, great apes and humans — emerged and diversified during the Miocene epoch, approximately 23 million to 5 million years ago. (The last common ancestor that humans had with chimpanzees lived about 6 million to 7 million years ago.)

Much remains unknown about the common ancestors of living apes and humans from the critical time when these branches diverged. Fossil evidence from this part of the primate family tree is scarce, and consists mostly of isolated teeth and broken jaw fragments. As such, researchers were not sure what the last common ancestors of living apes and humans might have looked like, and even whether they originated in Africa or Eurasia. [Continue reading…]


Octopus research shows that consciousness isn’t what makes humans special

Olivia Goldhill writes: Whether or not octopuses should be viewed as charming or terrifying very much depends on your personal perspective. But it’s hard to deny their intelligence.

Octopuses can squirt water at an annoyingly bright bulb until it short-circuits. They can tell humans apart (even those who are wearing the same uniform). And, according to Peter Godfrey-Smith, a philosophy professor at University of Sydney and City University of New York, they are the closest creature to an alien here on earth.

That’s because octopuses are the most complex animal with the most distant common ancestor to humans. There’s some uncertainty about which precise ancestor was most recently shared by octopuses and humans, but, Godfrey-Smith says, “It was probably an animal about the size of a leech or flatworm with neurons numbering perhaps in the thousands, but not more than that.”

This means that octopuses have very little in common with humans, evolution-wise. They have developed eyes, limbs, and brains via a completely separate route, with very different ancestors, from humans. And they seem to have come by their impressive cognitive functioning—and likely consciousness—by different means. [Continue reading…]


A new technology for detecting neutrinos represents a ‘monumental’ advance for science

Scientific American reports: Neutrinos are famously antisocial. Of all the characters in the particle physics cast, they are the most reluctant to interact with other particles. Among the hundred trillion neutrinos that pass through you every second, only about one per week actually grazes a particle in your body.

That rarity has made life miserable for physicists, who resort to building huge underground detector tanks for a chance at catching the odd neutrino. But in a study published today in Science, researchers working at Oak Ridge National Laboratory (ORNL) detected never-before-seen neutrino interactions using a detector the size of a fire extinguisher. Their feat paves the way for new supernova research, dark matter searches and even nuclear nonproliferation monitoring.

Under previous approaches, a neutrino reveals itself by stumbling across a proton or neutron amidst the vast emptiness surrounding atomic nuclei, producing a flash of light or a single-atom chemical change. But neutrinos deign to communicate with other particles only via the “weak” force—the fundamental force that causes radioactive materials to decay. Because the weak force operates only at subatomic distances, the odds of a tiny neutrino bouncing off of an individual neutron or proton are minuscule. Physicists must compensate by offering thousands of tons of atoms for passing neutrinos to strike. [Continue reading…]


Aliens in our midst

Douglas Fox writes: Leonid Moroz has spent two decades trying to wrap his head around a mind-boggling idea: even as scientists start to look for alien life in other planets, there might already be aliens, with surprisingly different biology and brains, right here on Earth. Those aliens have hidden in plain sight for millennia. They have plenty to teach us about the nature of evolution, and what to expect when we finally discover life on other worlds.

Moroz, a neuroscientist, saw the first hint of his discovery back in the summer of 1995, not long after arriving in the United States from his native Russia. He spent that summer at the Friday Harbor marine laboratory in Washington. The lab sat amid an archipelago of forested islands in Puget Sound – a crossroads of opposing tides and currents that carried hundreds of animal species past the rocky shore: swarms of jellyfish, amphipod crustaceans, undulating sea lilies, nudibranch slugs, flatworms, and the larvae of fish, sea stars and countless other animals. These creatures represented not just the far reaches of Puget Sound, but also the farthest branches of the animal tree of life. Moroz spent hours out on the pier behind the lab, collecting animals so he could study their nerves. He had devoted years to studying nervous systems across the animal kingdom, in hopes of understanding the evolutionary origin of brains and intelligence. But he came to Friday Harbor to find one animal in particular.

He trained his eyes to recognise its bulbous, transparent body in the sunlit water: an iridescent glint and fleeting shards of rainbow light, scattered by the rhythmic beating of thousands of hair-like cilia, propelling it through the water. This type of animal, called a ctenophore (pronounced ‘ten-o-for’ or ‘teen-o-for’), was long considered just another kind of jellyfish. But that summer at Friday Harbor, Moroz made a startling discovery: beneath this animal’s humdrum exterior was a monumental case of mistaken identity. From his very first experiments, he could see that these animals were unrelated to jellyfish. In fact, they were profoundly different from any other animal on Earth.

Moroz reached this conclusion by testing the nerve cells of ctenophores for the neurotransmitters serotonin, dopamine and nitric oxide, chemical messengers considered the universal neural language of all animals. But try as he might, he could not find these molecules. The implications were profound.

The ctenophore was already known for having a relatively advanced nervous system; but these first experiments by Moroz showed that its nerves were constructed from a different set of molecular building blocks – different from any other animal – using ‘a different chemical language’, says Moroz: these animals are ‘aliens of the sea’.

If Moroz is right, then the ctenophore represents an evolutionary experiment of stunning proportions, one that has been running for more than half a billion years. This separate pathway of evolution – a sort of Evolution 2.0 – has invented neurons, muscles and other specialised tissues, independently from the rest of the animal kingdom, using different starting materials. [Continue reading…]


First support for a physics theory of life

Natalie Wolchover writes: The biophysicist Jeremy England made waves in 2013 with a new theory that cast the origin of life as an inevitable outcome of thermodynamics. His equations suggested that under certain conditions, groups of atoms will naturally restructure themselves so as to burn more and more energy, facilitating the incessant dispersal of energy and the rise of “entropy” or disorder in the universe. England said this restructuring effect, which he calls dissipation-driven adaptation, fosters the growth of complex structures, including living things. The existence of life is no mystery or lucky break, he told Quanta in 2014, but rather follows from general physical principles and “should be as unsurprising as rocks rolling downhill.”

Since then, England, a 35-year-old associate professor at the Massachusetts Institute of Technology, has been testing aspects of his idea in computer simulations. The two most significant of these studies were published this month — the more striking result in the Proceedings of the National Academy of Sciences (PNAS) and the other in Physical Review Letters (PRL). The outcomes of both computer experiments appear to back England’s general thesis about dissipation-driven adaptation, though the implications for real life remain speculative.

“This is obviously a pioneering study,” Michael Lässig, a statistical physicist and quantitative biologist at the University of Cologne in Germany, said of the PNAS paper written by England and an MIT postdoctoral fellow, Jordan Horowitz. It’s “a case study about a given set of rules on a relatively small system, so it’s maybe a bit early to say whether it generalizes,” Lässig said. “But the obvious interest is to ask what this means for life.”

The paper strips away the nitty-gritty details of cells and biology and describes a simpler, simulated system of chemicals in which it is nonetheless possible for exceptional structure to spontaneously arise — the phenomenon that England sees as the driving force behind the origin of life. “That doesn’t mean you’re guaranteed to acquire that structure,” England explained. The dynamics of the system are too complicated and nonlinear to predict what will happen. [Continue reading…]


Half the atoms inside and around us came from outside the Milky Way

The Guardian reports: Nearly half of the atoms that make up our bodies may have formed beyond the Milky Way and travelled to the solar system on intergalactic winds driven by giant exploding stars, astronomers claim.

The dramatic conclusion emerges from computer simulations that reveal how galaxies grow over aeons by absorbing huge amounts of material that is blasted out of neighbouring galaxies when stars explode at the end of their lives.

Powerful supernova explosions can fling trillions of tonnes of atoms into space with such ferocity that they escape their home galaxy’s gravitational pull and fall towards larger neighbours in enormous clouds that travel at hundreds of kilometres per second.

Astronomers have long known that elements forged in stars can travel from one galaxy to another, but the latest research is the first to reveal that up to half of the material in the Milky Way and similar-sized galaxies can arrive from smaller galactic neighbours.

Much of the hydrogen and helium that falls into galaxies forms new stars, while heavier elements, themselves created in stars and dispersed in the violent detonations, become the raw material for building comets and asteroids, planets and life. [Continue reading…]


Why religion breeds both compassion and hatred

Tom Jacobs writes: President Donald Trump probably would not have been elected if not for the overwhelming support he enjoyed from evangelical Christians. This continues to puzzle and frustrate his opponents, who ask why they voted for a man whose campaign was largely based on hatred and vilification.

While it’s easy to blame tribalism or simple hypocrisy, newly published research suggests religiosity exerts two distinct psychological pulls.

It argues genuine piety can be a catalyst for compassion. But the shared rituals that create a cohesive congregation “may also produce hatred of others”—especially among those who lack deeply felt spiritual beliefs.

“Our data suggest that the social activities which accompany religion drive the hostility towards other groups, rather than the quality of one’s belief or the degree of devotion,” a research team led by Rod Lynch of the University of Missouri writes in the journal Evolutionary Psychological Science.

Building on research that dates back to the 1960s, Lynch and his colleagues remind us that religious people come in two varieties: true believers, and those who embrace a faith tradition as a way of fulfilling some secular need, such as peace of mind or connection to a community.

This distinction between “intrinsic” and “extrinsic” religiosity was laid out by the influential psychologist Gordon Allport in the 1960s, who reported ethnic prejudice was associated only with the latter. Much later research found this to also be true of homophobia. [Continue reading…]


How to turn a fox into a dog

Lee Dugatkin and Lyudmila Trut: Deep inside my soul,” says Lyudmila Trut, “is a pathological love for animals.” She inherited this from her mother, who was a great dog lover. Lyudmila had grown up with dogs as pets, and even during World War II, when food was horribly scarce, her mother would feed starving stray dogs, telling her, “If we don’t feed them, Lyudmila, how will they survive? They need people.” Following her mother’s example, Lyudmila always carries some kind of treat in a pocket in case she encounters a stray dog. And she’s never forgotten that domesticated animals need people. She knows that this is how we’ve designed them.

In 1958, Lyudmila was just finishing up her studies at Moscow State University, home of Leonid Krushinsky, a pioneering Russian researcher in animal behavior. Dmitri Belyaev was friends with Krushinsky and admired his work. Belyaev had recently accepted a position as vice director of a new research institute in a giant Soviet city of science called Akademgorodok, near Novosibirsk, Siberia. He was searching for someone to lead an experiment he would begin in earnest at Akademgorodok. Dmitri intended to run an experiment domesticating silver foxes, and so the person he sought needed the kind of sophisticated skills in animal behavior that Krushinksy taught.

Belyaev went to visit Krushinsky at his office at Moscow State’s Sparrow Hill campus for advice about who might work with him on this experiment. Ensconced in the grand setting of Krushinsky’s building, with its palatial ceilings, marble floors, ornate columns, and fine art statues, he described his plans for the experiment and explained that he was looking for talented graduates to assist with the work. Krushinsky put the word out, and when Lyudmila heard about the opportunity, she was immediately captivated. Her own undergraduate work had been on the behavior of crabs, and as fascinating as their complex behavior could be, the prospect of working with foxes, so closely related to her beloved dogs, and with such a well-respected scientist as Belyaev, was tantalizing.

In early 1958, Lyudmila went to meet with Belyaev at his office. She was immediately struck by how unusual he was for a male Soviet scientist, especially one of his rank. Many were quite high-handed, and condescending to women. Lyudmila, who has a genial, smiling manner and stands just five feet tall, with her wavy brown hair cropped quite short, looked young for her age, and she hadn’t even finished her undergraduate studies, but Dmitri spoke to her as an equal. She was riveted, she recalls, by his piercing blue eyes, which so strongly communicated his intelligence and drive, but also emanated an extraordinary empathy.

She felt privileged to be invited into the confidence of this extraordinary man, who shared with her so openly about the bold work he was proposing. She had never experienced such a distinctive combination of confidence and warmth in a person. Dmitri told Lyudmila what he had in mind. “He told me that he wanted to make a dog out of a fox,” she recalls. Probing how creative she would be about conducting the experiment, Belyaev asked her, “You are now located on a fox farm that has several hundred foxes, and you need to select the 20 calmest ones for the experiment. How will you do it?” She had no experience whatsoever with foxes, and had only a vague notion of what the fox farms might be like and what sort of welcome she might receive at them. But she was a confident young woman, and she did the best she could to suggest some reasonable possibilities. She would try different methods, she said, talk to people who had worked with foxes, read up on what was known in the literature. Dmitri sat back and listened, gauging how committed she would be to the work and to developing techniques for such a novel study. She must be not only rigorously scientific, but also quite inventive. Was she really ready to go to Novosibirsk, to move to Akademgorodok, he asked her? After all, moving to the heart of Siberia was a life change not to be taken lightly. [Continue reading…]


Humans first settled in Australia as early as 65,000 years ago

Science News reports: Tools, paints and other artifacts excavated from an ancient rock-shelter in northern Australia are giving new glimpses into early life Down Under. The first humans may have arrived on the continent 65,000 years ago — 5,000 years earlier than previously thought — and they were sophisticated craftspeople, researchers report July 19 in Nature.

Archaeologists unearthed three distinct layers of artifacts at Madjedbebe, Australia’s oldest known site of human habitation, during digs in 2012 and 2015. The oldest, deepest layer contained more than 10,000 relics of human handiwork. This cache included the world’s oldest polished ax heads, Australia’s oldest seed-grinding and pigment-processing tools, stone points that may have been spearheads, as well as hearths and other remnants of human activity.

“When people think about our ancient ancestors, they either tend to have a view that our ancestors must have been primitive, less culturally diverse, or they take the view that our ancestors were probably extraordinarily culturally impressive,” says Peter Hiscock, an archaeologist at the University of Sydney who was not involved in the study. “This indicates the latter view. The moment people get to Australia, they’re doing all this really smart stuff.” They were probably building fires to light nighttime activities, grinding seeds for food and using ochre paints to decorate cave walls or their own bodies, Hiscock says. [Continue reading…]