Author Archives: Attention to the Unseen

Study suggests human proclivity for violence gets modulated but is not necessarily diminished by culture

A new study (by José Maria Gómez et al) challenges Steven Pinker’s rosy picture of the state of the world. Science magazine reports: Though group-living primates are relatively violent, the rates vary. Nearly 4.5% of chimpanzee deaths are caused by another chimp, for example, whereas bonobos are responsible for only 0.68% of their compatriots’ deaths. Based on the rates of lethal violence seen in our close relatives, Gómez and his team predicted that 2% of human deaths would be caused by another human.

To see whether that was true, the researchers dove into the scientific literature documenting lethal violence among humans, from prehistory to today. They combined data from archaeological excavations, historical records, modern national statistics, and ethnographies to tally up the number of humans killed by other humans in different time periods and societies. From 50,000 years ago to 10,000 years ago, when humans lived in small groups of hunter-gatherers, the rate of killing was “statistically indistinguishable” from the predicted rate of 2%, based on archaeological evidence, Gómez and his colleagues report today in Nature.

Later, as human groups consolidated into chiefdoms and states, rates of lethal violence shot up — as high as 12% in medieval Eurasia, for example. But in the contemporary era, when industrialized states exert the rule of law, violence is lower than our evolutionary heritage would predict, hovering around 1.3% when combining statistics from across the world. That means evolution “is not a straitjacket,” Gómez says. Culture modulates our bloodthirsty tendencies.

The study is “innovative and meticulously conducted,” says Douglas Fry, an anthropologist at the University of Alabama, Birmingham. The 2% figure is significantly lower than Harvard University psychologist Steven Pinker’s much publicized estimate that 15% of deaths are due to lethal violence among hunter-gatherers. The lower figure resonates with Fry’s extensive studies of nomadic hunter-gatherers, whom he has observed to be less violent than Pinker’s work suggests. “Along with archaeology and nomadic forager research, this [study] shoots holes in the view that the human past and human nature are shockingly violent,” Fry says. [Continue reading…]

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Freedom for some requires the enslavement of others

Maya Jasanoff writes: One hundred and fifty years after the Thirteenth Amendment abolished slavery in the United States, the nation’s first black president paid tribute to “a century and a half of freedom—not simply for former slaves, but for all of us.” It sounds innocuous enough till you start listening to the very different kinds of political rhetoric around us. All of us are not free, insists the Black Lives Matter movement, when “the afterlife of slavery” endures in police brutality and mass incarceration. All of us are not free, says the Occupy movement, when student loans impose “debt slavery” on the middle and working classes. All of us are not free, protests the Tea Party, when “slavery” lurks within big government. Social Security? “A form of modern, twenty-first-century slavery,” says Florida congressman Allen West. The national debt? “It’s going to be like slavery when that note is due,” says Sarah Palin. Obamacare? “Worse than slavery,” says Ben Carson. Black, white, left, right—all of us, it seems, can be enslaved now.

Americans learn about slavery as an “original sin” that tempted the better angels of our nation’s egalitarian nature. But “the thing about American slavery,” writes Greg Grandin in his 2014 book The Empire of Necessity, about an uprising on a slave ship off the coast of Chile and the successful effort to end it, is that “it never was just about slavery.” It was about an idea of freedom that depended on owning and protecting personal property. As more and more settlers arrived in the English colonies, the property they owned increasingly took the human form of African slaves. Edmund Morgan captured the paradox in the title of his classic American Slavery, American Freedom: “Freedom for some required the enslavement of others.” When the patriots protested British taxation as a form of “slavery,” they weren’t being hypocrites. They were defending what they believed to be the essence of freedom: the right to preserve their property.

The Empire of Necessity explores “the fullness of the paradox of freedom and slavery” in the America of the early 1800s. Yet to understand the chokehold of slavery on American ideas of freedom, it helps to go back to the beginning. At the time of the Revolution, slavery had been a fixture of the thirteen colonies for as long as the US today has been without it. “Slavery was in England’s American colonies, even its New England colonies, from the very beginning,” explains Princeton historian Wendy Warren in her deeply thoughtful, elegantly written New England Bound, an exploration of captivity in seventeenth-century New England. The Puritan ideal of a “city on a hill,” long held up as a model of America at its communitarian best, actually rested on the backs of “numerous enslaved and colonized people.” [Continue reading…]

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Video: Aurora Borealis over Iceland

 

Time reports: Streetlights across much of Iceland’s capital were switched off Wednesday night so its citizens could make the most of the otherworldly glow of the aurora borealis dancing in the sky above them — without the usual interference from light pollution.

Lights in central Reykjavik and several outlying districts went out for about an hour at 10 p.m. local time, and residents were encouraged to turn off lights at home, the Iceland Monitor reported.

While those in Iceland can expect to see the aurora borealis, also known as the northern lights, at any time from September to May, high solar-particle activity combined with clear skies on Wednesday created unusually perfect conditions. [Continue reading…]

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Something is shifting out there in the ocean

Rebecca Kessler writes: ‘It’s hard to believe that a 40-ton animal can get hidden. They’re sneaky.’ Charles ‘Stormy’ Mayo was scanning the sea from the deck of the R/V Shearwater searching for omens: a cloud of vapour, a patch of white water, a fluke. A few minutes earlier someone had spotted the first North Atlantic right whales of the day. But now they were down below and out of sight in 80 feet of murky seawater. Feeding, most likely.

Finally, a whale’s head emerged briefly on the sea surface. Then a slab of black back followed by the silhouette of flukes, signaling another deep dive. The appearance lasted maybe a second and a half. Groans from the crew, who did not quite manage to snap a photo that could help identify the whale, one of an early March influx that foretold another strong season in Cape Cod Bay. ‘There’s probably a bunch of whales here but it’s going to drive us crazy,’ Mayo chimed in. ‘I’m going to say there are probably three. It’s hard as hell to tell.’

The world’s rarest whales – Eubalaena glacialis – have been visiting the bay in late winter and early spring for as long as anyone can remember. But Mayo and his team at the Center for Coastal Studies (CCS) in Provincetown documented a puzzling uptick in recent years. Not just a few dozen animals, as was typical, but hundreds were showing up and, in one year, darn-near two-thirds of the world’s entire living population of around 500 North Atlantic right whales. ‘Right Whale Kingdom’ Mayo has called the bay. Simultaneously, the whales went AWOL from their usual summer feeding grounds 300 miles to the northeast in Canada’s Bay of Fundy and elsewhere, further mystifying researchers.

The Shearwater idled, waiting. The whales remained deep down, scooping up patches of zooplankton and straining out the seawater through the long strips of baleen in their mouths. Scooping and straining, scooping and straining. A change in the location of their preferred food is the most likely explanation for the whales’ wandering itinerary, Mayo said. Something is shifting out there in the ocean. As with so much else about their lives, only the whales know what it is. [Continue reading…]

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Watching evolution happen in two lifetimes

Emily Singer writes: When Rosemary and Peter Grant first set foot on Daphne Major, a tiny island in the Galápagos archipelago, in 1973, they had no idea it would become a second home. The husband and wife team, now emeritus biology professors at Princeton University, were looking for a pristine environment in which to study evolution. They hoped that the various species of finches on the island would provide the perfect means for uncovering the factors that drive the formation of new species.

The diminutive island wasn’t a particularly hospitable place for the Grants to spend their winters. At less than one-hundredth the size of Manhattan, Daphne resembles the tip of a volcano rising from the sea. Visitors must leap off the boat onto the edge of a steep ring of land that surrounds a central crater. The island’s vegetation is sparse. Herbs, cactus bushes and low trees provide food for finches — small, medium and large ground finches, as well as cactus finches — and other birds. The Grants brought with them all the food and water they would need and cooked meals in a shallow cave sheltered by a tarp from the baking sun. They camped on Daphne’s one tiny flat spot, barely larger than a picnic table.

Though lacking in creature comforts, Daphne proved to be a fruitful choice. The Galápagos’ extreme climate — swinging between periods of severe drought and bountiful rain — furnished ample natural selection. Rainfall varied from a meter of rain in 1983 to none in 1985. A severe drought in 1977 killed off many of Daphne’s finches, setting the stage for the Grants’ first major discovery. During the dry spell, large seeds became more plentiful than small ones. Birds with bigger beaks were more successful at cracking the large seeds. As a result, large finches and their offspring triumphed during the drought, triggering a lasting increase in the birds’ average size. The Grants had observed evolution in action.

That striking finding launched a prolific career for the pair. They visited Daphne for several months each year from 1973 to 2012, sometimes bringing their daughters. Over the course of their four-decade tenure, the couple tagged roughly 20,000 birds spanning at least eight generations. (The longest-lived bird on the Grants’ watch survived a whopping 17 years.) They tracked almost every mating and its offspring, creating large, multigenerational pedigrees for different finch species. They took blood samples and recorded the finches’ songs, which allowed them to track genetics and other factors long after the birds themselves died. They have confirmed some of Darwin’s most basic predictions and have earned a variety of prestigious science awards, including the Kyoto Prize in 2009.

Now nearly 80, the couple have slowed their visits to the Galápagos. These days, they are most excited about applying genomic tools to the data they collected. They are collaborating with other scientists to find the genetic variants that drove the changes in beak size and shape that they tracked over the past 40 years. Quanta Magazine spoke with the Grants about their time on Daphne; an edited and condensed version of the conversation follows. [Continue reading…]

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Rewriting Earth’s creation story

Earth

Rebecca Boyle writes: Humanity’s trips to the moon revolutionized our view of this planet. As seen from another celestial body, Earth seemed more fragile and more precious; the iconic Apollo 8 image of Earth rising above the lunar surface helped launch the modern environmental movement. The moon landings made people want to take charge of Earth’s future. They also changed our view of its past.

Earth is constantly remaking itself, and over the eons it has systematically erased its origin story, subsuming and cannibalizing its earliest rocks. Much of what we think we know about the earliest days of Earth therefore comes from the geologically inactive moon, which scientists use like a time capsule.

Ever since Apollo astronauts toted chunks of the moon back home, the story has sounded something like this: After coalescing from grains of dust that swirled around the newly ignited sun, the still-cooling Earth would have been covered in seas of magma, punctured by inky volcanoes spewing sulfur and liquid rock. The young planet was showered in asteroids and larger structures called planetisimals, one of which sheared off a portion of Earth and formed the moon. Just as things were finally settling down, about a half-billion years after the solar system formed, the Earth and moon were again bombarded by asteroids whose onslaught might have liquefied the young planet — and sterilized it.

Geologists named this epoch the Hadean, after the Greek version of the underworld. Only after the so-called Late Heavy Bombardment quieted some 3.9 billion years ago did Earth finally start to morph into the Edenic, cloud-covered, watery world we know.

But as it turns out, the Hadean may not have been so hellish. New analysis of Earth and moon rocks suggest that instead of a roiling ball of lava, baby Earth was a world with continents, oceans of water, and maybe even an atmosphere. It might not have been bombarded by asteroids at all, or at least not in the large quantities scientists originally thought. The Hadean might have been downright hospitable, raising questions about how long ago life could have arisen on this planet. [Continue reading…]

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Tardigrades: The most fascinating animals known to science

 

Brian Resnick writes: Paul Bartels gets a rush every time he discovers a new species of tardigrade, the phylum of microscopic animals best known for being both strangely cute and able to survive the vacuum of space.

“The first paper I wrote describing a new species, there was a maternal-paternal feeling — like I just gave birth to this new thing,” he tells me on a phone call.

The rush comes, in part, because tardigrades are the most fascinating animals known to science, able to survive in just about every environment imaginable. “There are some ecosystems in the Antarctic called nunataks where the wind blows away snow and ice, exposing outcroppings of rocks, and the only things that live on them are lichens and tardigrades,” says Bartels, an invertebrate zoologist at Warren Wilson College in North Carolina.

Pick up a piece of moss, and you’ll find tardigrades. In the soil: tardigrades. The ocean: You get it. They live on every continent, in every climate, and in every latitude. Their extreme resilience has allowed them to conquer the entire planet.

And though biologists have known about tardigrades since the dawn of the microscope, they’re only just beginning to understand how these remarkable organisms are able to survive anywhere. [Continue reading…]

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Why neuroscientists need to study the crow

crow

Grigori Guitchounts writes: The animals of neuroscience research are an eclectic bunch, and for good reason. Different model organisms—like zebra fish larvae, C. elegans worms, fruit flies, and mice — give researchers the opportunity to answer specific questions. The first two, for example, have transparent bodies, which let scientists easily peer into their brains; the last two have eminently tweakable genomes, which allow scientists to isolate the effects of specific genes. For cognition studies, researchers have relied largely on primates and, more recently, rats, which I use in my own work. But the time is ripe for this exclusive club of research animals to accept a new, avian member: the corvid family.

Corvids, such as crows, ravens, and magpies, are among the most intelligent birds on the planet — the list of their cognitive achievements goes on and on — yet neuroscientists have not scrutinized their brains for one simple reason: They don’t have a neocortex. The obsession with the neocortex in neuroscience research is not unwarranted; what’s unwarranted is the notion that the neocortex alone is responsible for sophisticated cognition. Because birds lack this structure—the most recently evolved portion of the mammalian brain, crucial to human intelligence—neuroscientists have largely and unfortunately neglected the neural basis of corvid intelligence.

This makes them miss an opportunity for an important insight. Having diverged from mammals more than 300 million years ago, avian brains have had plenty of time to develop along remarkably different lines (instead of a cortex with its six layers of neatly arranged neurons, birds evolved groups of neurons densely packed into clusters called nuclei). So, any computational similarities between corvid and primate brains — which are so different neurally — would indicate the development of common solutions to shared evolutionary problems, like creating and storing memories, or learning from experience. If neuroscientists want to know how brains produce intelligence, looking solely at the neocortex won’t cut it; they must study how corvid brains achieve the same clever behaviors that we see in ourselves and other mammals. [Continue reading…]

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Walking improves creativity

Olivia Goldhill writes: For centuries, great thinkers have instinctively stepped out the door and begun walking, or at the very least pacing, when they needed to boost creativity. Charles Dickens routinely walked for 30 miles a day, while the philosopher Friedrich Nietzsche declared, “All truly great thoughts are conceived while walking.”

But in recent years, as lives have become increasingly sedentary, the idea has been put to the test. The precise physiology is unknown, but professors and therapists are turning what was once an unquestioned instinct into a certainty: Walking influences our thinking, and somehow improves creativity.

Last year, researchers at Stanford found that people perform better on creative divergent thinking tests during and immediately after walking. The effect was similar regardless of whether participants took a stroll inside or stayed inside, walking on a treadmill and staring at a wall. The act of walking itself, rather than the sights encountered on a saunter, was key to improving creativity, they found. [Continue reading…]

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