Smallpox, Salmonella, and Cocoliztli

Tuesday, February 21st, 2017

When the Spanish arrived in the New World, they conquered great empires through a combination of Guns, Germs, and Steel — but mainly germs:

In 1519, when forces led by Spanish conquistador Hernando Cortés arrived in Mexico, the native population was estimated at about 25 million. A century later, after a Spanish victory and a series of epidemics, numbers had plunged to around 1 million.

The largest of these disease outbreaks were known as cocoliztli (from the word for ‘pestilence’ in Nahuatl, the Aztec language). Two major cocoliztli, beginning in 1545 and 1576, killed an estimated 7 million to 18 million people living in Mexico’s highland regions.

“In the cities and large towns, big ditches were dug, and from morning to sunset the priests did nothing else but carry the dead bodies and throw them into the ditches,” noted a Franciscan historian who witnessed the 1576 outbreak.

There has been little consensus on the cause of cocoliztli — although measles, smallpox and typhus have all been mooted. In 2002, researchers at the National Autonomous University of Mexico (UNAM) in Mexico City proposed that a viral haemorrhagic fever, exacerbated by a catastrophic drought, was behind the carnage2. They compared the magnitude of the 1545 outbreak to that of the Black Death in fourteenth-century Europe.

A couple new studies point to salmonella:

In an attempt to settle the question, a team led by evolutionary geneticist Johannes Krause at the Max Planck Institute for the Science of Human History in Jena, Germany, extracted and sequenced DNA from the teeth of 29 people buried in the Oaxacan highlands of southern Mexico. All but five were linked to a cocoliztli that researchers think ran from 1545 to 1550.

Ancient bacterial DNA recovered from several of the people matched that of Salmonella, based on comparisons with a database of more than 2,700 modern bacterial genomes.

Further sequencing of short, damaged DNA fragments from the remains allowed the team to reconstruct two genomes of a Salmonella enterica strain known as Paratyphi C. Today, this bacterium causes enteric fever, a typhus-like illness, that occurs mostly in developing countries. If left untreated, it kills 10–15% of infected people.

It’s perfectly reasonable that the bacterium could have caused this epidemic, says Schroeder. “They make a really good case.” But María Ávila-Arcos, an evolutionary geneticist at UNAM, isn’t convinced. She notes that some people suggest that a virus caused the cocoliztli, and that wouldn’t have been picked up by the team’s method.

Krause and his colleagues’ proposal is helped by another study posted on bioRxiv last week, which raises the possibility that Salmonella Paratyphi C arrived in Mexico from Europe.

A team led by Mark Achtman, a microbiologist at the University of Warwick in Coventry, UK, collected and sequenced the genome of the bacterial strain from the remains of a young woman buried around 1200 in a cemetery in Trondheim, Norway. It is the earliest evidence for the now-rare Salmonella strain, and proof that it was circulating in Europe, according to the study.

If you read the firsthand account of The Discovery And Conquest Of Mexico by Bernal Diaz Del Castillo — and I highly recommend that you do! — he mentions smallpox specifically five separate times:

Xicotencatl made various other offers of his services in the name of his country. This Xicotencatl was a tall man, broad shouldered, and well built, with a large fresh coloured face, full of scars, as if pitted with the smallpox. He may have been about thirty-five years of age, and was earnest and dignified in his deportment. Cortes thanked him most sincerely, saying, ” he would acknowledge them as vassals of our emperor, and would, for the future, look upon them as our friends.

[...]

But to return to Narvaez. He happened to have a negro servant with him ill with the smallpox, through whom this terrific disease, which, according to the accounts of the inhabitants, was previously unknown in the country, spread itself through New Spain, where it created the greater devastation, from the poor Indians, in their ignorance, solely applying cold water as a remedy, with which they constantly bathed themselves; so that vast numbers were cut off before they had the blessing of being received into the bosom of the Christian church.

[...]

About this time another king had been raised to the throne of Mexico, as the former, who beat us out of the town, had died of the smallpox. The new monarch was a nephew, or, at least, a very near relative of Motecusuma, and was called Quauhtemoctzin. He was about twenty-five years of age, and a very well-bred man for an Indian. He was likewise a person of great courage, and soon made himself so greatly feared among his people that they trembled in his presence. His wife was one of Motecusuma’s daughters, and passed for a great beauty among her countrywomen.

[...]

This expedition was attended by many beneficial results ; for the whole country was thereby tranquilized, while it spread a vast idea of Cortes’ justice and bravery throughout the whole of New Spain; so that every one feared him, and particularly Quauhtemoctzin, the new king of Mexico. Indeed Cortes’ authority rose at once to so great a height, that the inhabitants came from the most distant parts to lay their disputes before him, particularly respecting the election of caziques, right of tenure, and division of property and subjects. About this time thousands of people were carried off by the smallpox, and among them numbers of caziques ; and Cortes, as though he had been lord of the whole country, appointed the new caziques, but made a point of nominating those who had the best claim.

[...]

On our arrival in Tlascalla, we found that our old friend Maxixcatzin, one of his majesty’s most faithful vassals, was no more, he having died of the smallpox. We were all sorely grieved at this loss, and Cortes himself, as he assured us, felt it as much as if he had lost his own father. We put on black cloaks in mourning for him, and paid the last honours to the remains of our departed friend, in conjunction with his sons and relations.

My reaction to that book, by the way, was, Why didn’t we read this in school?

Real history is nothing like school history. Oddly, real history is more like a swords-and-sorcery novel: evil priests, hair matted with blood, commit human sacrifices atop pyramids amidst a city built on a lake inside a volcanic crater; frenzied fighting ensues.

A Hotel California for Apex Predators

Monday, February 20th, 2017

P-45, the King of Malibu, is a hundred-and-fifty-pound male mountain lion:

After killing an alpaca at a Malibu winery in late 2015, he was captured and fitted with a G.P.S. collar by the National Park Service, which designated him the forty-fifth subject in a long-running study, led by a wildlife ecologist named Seth Riley, on the mountain lions of Los Angeles. (The “P” comes from Puma concolor, the species whose common names include puma, panther, catamount, cougar, and mountain lion.) Since P-45 was collared, according to Phillips, he has killed some sixty goats, sheep, llamas, and alpacas, a miniature horse, and a four-hundred-and-fifty-pound heifer: members of the class of rustic pet known as “hobby animals.” Gallingly, he has eaten little — a nibble of heart meat here, a nip of scrotum there. Except in the case of pygmy goats, for which he has a taste, he seems to kill for sport.

Rickards, who has short blond hair and a cheerful manner, grew up on the ranch and runs a cat rescue there. She and Phillips have horses and dogs and, until recently, had alpacas. Then one night P-45 jumped into the alpaca pen, killing two of them. When it happened again last spring, and three more died, Phillips gave away the rest of the herd and turned his attention to pursuing the culprit. To Phillips, P-45 is a sociopath, a freak — “the John Wayne Gacy of mountain lions.”

Mountain Lion P-45

The Santa Monica Mountains extend from the Pacific Coast through the Hollywood Hills, to end in Griffith Park. Urban though Los Angeles is, its mountains are furrowed with densely vegetated canyons full of deer and coyotes, cactuses, live oaks, wheeling hawks — a patchwork of public and private holdings claimed both by top carnivores and by their human counterparts.

The real estate is increasingly contested. At some two hundred and forty square miles, the range is the perfect size for one or two dominant males and several females, along with their young. The National Park Service study is currently tracking ten mountain lions in the area, including three breeding males. There is also an unknown number of uncollared lions. Living at such close quarters intensifies the lions’ natural territorialism; in this population, the leading cause of death is conflict with other lions. But adolescent lions who set out in search of their own hunting grounds often come to an impasse. The range is bounded by the Pacific Ocean to the south and the Hollywood Freeway (the 101) to the north, and bisected by the 405 between Brentwood and Bel Air. Just as the roads keep native lions in, they also keep outside lions from entering, and first-order inbreeding has become common. Lush but confined, the mountains are a cushy prison, a Hotel California for apex predators, whose future is threatened by a double deficiency: not enough space for a group of lions with not enough genetic differences among them.

As a result, the mountain-lion population in the Santa Monica Mountains is in danger of entering an extinction vortex, a downward spiral in which everything starts to fail. “They could be in the process of genetic flatlining,” Robert Wayne, an evolutionary biologist at the University of California, Los Angeles, says. “Without our assistance, the Santa Monica Mountain pumas are likely to go extinct.” This is what nearly happened to the Florida panthers, in the mid-nineties, when intensive inbreeding caused physical changes that hindered reproduction. According to Riley, who recently published a paper on the subject, if similar problems occur and no new lions enter the area the likelihood of L.A.’s lions disappearing in fifty years is 99.7 per cent. But genetic rescue can come in the form of just one new animal in each generation — in Florida, where the population was larger, it took just six females from Texas to reverse the spiral.

From this point of view, Los Angeles can’t spare a single cat, and certainly not one matching P-45’s profile. According to a preliminary genetic analysis done at Wayne’s lab, P-45 comes from north of the 101: he is an outsider, a lion who successfully navigated the freeway and miles of suburbs to introduce his precious DNA to the Santa Monicas. Under threat, P-45 has inspired a committed following. In November, an editorial in the Los Angeles Times titled “Save P-45” defended his behavior as entirely natural. “Killing P-45 is not the answer,” the editorial said. “Surely there is a better way to manage the conflicts that arise when humans and their domestic animals move into areas that have long served as habitat for wildlife.”

P-45’s alien provenance aggravates the unease that Phillips and his neighbors feel. “I know P-45 is not indigenous to here,” Phillips told me. “I think he was a killer someplace else.” He added, “I’m not too happy about P-45’s genes getting passed down.” Though the young generally travel with their mothers — mountain-lion fathers are more likely to kill their kittens than to train them — he saw the potential for P-45 to accustom his offspring to a life of theft and slaughter. Besides, he said, “I’m tired of living inside a biology project.” If the California Department of Fish and Wildlife, which manages the state’s mountain-lion population, or the National Park Service, which he blames for protecting P-45, refused to solve the problem, he warned that vigilante justice would prevail.

“Somebody’s going to shoot him soon,” Phillips said. “They’re just not going to report it. They’re not going to call N.P.S., not going to call Fish and Wildlife. They’re just going to shoot him, pound the collar off with a hammer, put it in a lead box in a bucket of water, and bury P-45 ten feet deep. That will be the end of that story. He will pass from reality into legend.”

Puma concolor, an evolutionary adept that, unlike the sabre-toothed cat, survived the Late Pleistocene Extinction, is found from Tierra del Fuego to the Canadian Yukon. Until successive extermination campaigns largely eradicated mountain lions from the Midwest and the East, they ranged throughout the United States. Now, as urbanization in the West encroaches on their remaining habitat, some are making audacious attempts to reclaim ceded lands. In 2011, a cat from South Dakota travelled more than fifteen hundred miles, to Greenwich, Connecticut, before being struck and killed by an S.U.V. on the Wilbur Cross Parkway.

Los Angeles is one of two megacities in the world that have a population of big cats. In the other, Mumbai, leopards live in Sanjay Gandhi National Park and occasionally eat the humans who make their homes around its edge. Though there have been instances of mountain lions targeting people in California — between 1986 and 2014, there were three fatal attacks — it has never happened in Los Angeles County. (Since the beginning of the twentieth century, according to the Mountain Lion Foundation, there have been fewer than thirty fatal attacks in North America; it is an often cited fact that vending machines kill more people than mountain lions do.) “They’re called ghost cats for a reason — they’re very elusive,” Jeff Sikich, a carnivore biologist with the National Park Service, who manages the field work for the mountain-lion study, told me. “We’ve seen with our data that they do a great job at avoiding us.” But, he said, “in this urban, fragmented landscape, they see us almost every day.”

The Billy Beane of Murder

Sunday, February 19th, 2017

Thomas Hargrove, a 61-year-old retired news reporter from Virginia, was always the numbers guy at his paper:

In 2004, Hargrove’s editors asked him to look into statistics surrounding prostitution. The only way to study that was to get a copy of the nation’s most comprehensive repository of criminal statistics: the FBI’s Uniform Crime Report, or UCR. When Hargrove called up a copy of the report from the database library at the University of Missouri, attached to it was something he didn’t expect: the Supplementary Homicide Report. “I opened it up, and it was a record I’d never seen before,” he says. “Line by line, every murder that was reported to the FBI.”

[...]

Every year he downloaded and crunched the most recent data set. What really shocked him was the number of murder cases that had never been cleared. (In law enforcement, a case is cleared when a suspect is arrested, whatever the eventual outcome.) Hargrove counted 211,487, more than a third of the homicides recorded from 1980 to 2010. Why, he wondered, wasn’t the public up in arms about such a large number of unsolved murders?

To make matters worse, Hargrove saw that despite a generation’s worth of innovation in the science of crime fighting, including DNA analysis, the rate of cleared cases wasn’t increasing but decreasing — plummeting, even. The average homicide clearance rate in the 1960s was close to 90 percent; by 2010 it was solidly in the mid-’60s. It has fallen further since.

[...]

His innovation was to teach a computer to spot trends in unsolved murders, using publicly available information that no one, including anyone in law enforcement, had used before. This makes him, in a manner of speaking, the Billy Beane of murder. His work shines light on a question that’s gone unanswered for too long: Why, exactly, aren’t the police getting any better at solving murder? And how can we even dream of reversing any upticks in the homicide rate while so many killers remain out on the streets?

It took a few years for Hargrove’s editors at Scripps to agree to give him enough time to lose himself in the FBI’s homicide data. With help from a University of Missouri grad student, Hargrove first dumped the homicide report into statistics software in 2008. He spent months trying to develop an algorithm that would identify unsolved cases with enough commonalities to suggest the same murderer. Eventually, he decided to reverse-engineer the algorithm by testing his ideas against one well-known case, that of Gary Ridgway, the so-called Green River Killer, who confessed to killing 48 women over two decades in the Seattle area. Hargrove thought that if he could devise an algorithm that turned up the Green River Killer’s victims, he’d know he was on the right track.

“We found a hundred things that didn’t work,” he recalls. Finally, he settled on four characteristics for what’s called a cluster analysis: geography, sex, age group, and method of killing. For gender, he stuck with women, since they make up the vast majority of multiple-murder victims who aren’t connected to gang-related activity. When he used women between the ages of 20 and 50 — the cohort most commonly targeted by serial killers — the algorithm lit up like a slot machine. “It became clear that this thing was working,” he says. “In fact, it was working too well.”

The Green River Killer came up right away in this algorithm. That was good news. Hargrove’s algorithm also pulled up 77 unsolved murders in Los Angeles, which he learned were attributed to several different killers the police were pursuing (including the so-called Southside Slayer and, most recently, the Grim Sleeper), and 64 unsolved murders of women in Phoenix.

Then there was a second group of possible serial killers, those unrecognized by local police. “The whole point of the algorithm was to find the low-hanging fruit, the obvious clusters,” Hargrove says. “But there were dozens and dozens of them all over the country.”

In 2015, Scripps spun off the last of its newspapers, and Hargrove and the other print reporters lost their jobs. “The only guy who left with a skip was me,” he says. Hargrove, who was 59 at the time and had worked at the company for 37 years, qualified for a large severance and a nice pension, leaving him well-covered. Now he had enough time to go all in on his data project. He founded the Murder Accountability Project, or MAP, a tiny nonprofit seeking to make FBI murder data more widely and easily available.

Using Freedom of Information Act (FOIA) requests, MAP has tried to chase down data from the many municipalities and counties that weren’t supplying their murder data to the FBI, out of bureaucratic laziness, a lack of manpower, or perhaps just rank incompetence. MAP has already assembled case details on 638,454 homicides from 1980 through 2014, including 23,219 cases that hadn’t been reported to the FBI. This is the most complete list of case-level details of U.S. murders available anywhere, and the group’s website has open-sourced all of it. Anyone with statistical analysis software, available for free online, can start looking, across jurisdictions, for serial killers. Anyone can compare convicted killers’ timelines against the timing of unsolved murders to determine if a connection is plausible. “You can call up your hometown and look and see if you see anything suspicious,” Hargrove says. “If you’re the father of a murdered daughter, you can call up her record, and you can see if there might be other records that match. We wanted to be able to crowdsource murder.”

No, the wooly mammoth won’t be resurrected by 2019

Saturday, February 18th, 2017

No, the wooly mammoth won’t be resurrected by 2019:

“Our aim is to produce a hybrid elephant-mammoth embryo,” Harvard’s George Church told The Guardian. “Actually, it would be more like an elephant with a number of mammoth traits. We’re not there yet, but it could happen in a couple of years.”

The key word there is embryo. Church’s team — the Wooly Mammoth Revival project — is using CRISPR gene-editing technology to put genetic traits collected from frozen mammoth corpses into Asian elephant DNA.

So far, they’ve managed to incorporate traits of the mammoth’s ears, fat, and hair into elephant DNA. In a few years they hope to make an embryo, but that’s a long way from creating a viable embryo. A viable embryo would have to be able to survive long enough to move from a Petri dish to some kind of womb — and then it would have to grow into a healthy calf that the team could successfully deliver and raise.

Artificial gestation is considered the most likely option for any viable embryo, because Asian elephants, the closest living relatives of mammoths, are currently endangered. Church has created an artificial womb capable of gestating a mouse embryo for 10 days but that’s a far cry from the 660-day gestation period of an elephant calf.

So while an embryo may indeed be possible by 2019, there’s no telling how many years would stretch between that milestone and the actual reintroduction of the woolly mammoth. Researchers have already created embryos of chickens with dinosaur snouts, for example, and those dino-chickens aren’t clucking around a co-op. The first attempts to make a living mammoth are many more years away.

Flag Football Is More Dangerous

Friday, February 17th, 2017

Flag football is more dangerous than tackle football:

The study, which examined 3,794 players in grades 2-7 in two tackle football leagues and one flag football league, is one of the largest to compare injury rates in the different types of football. It was published online last week in the Orthopaedic Journal of Sports Medicine.

[...]

All injuries that resulted in loss of playing time were recorded. An injury was considered severe if it resulted in a concussion, fracture or ligament tear. All other injuries were considered nonsevere.

Across all leagues, 128 injuries were reported out of 46,416 exposures—that is, a practice or a game. The overall injury rate was 2.76 injuries per 1,000 exposures, which Dr. Peterson notes is similar to the injury rate in high school football.

Tackle football players in the study reported 2.6 injuries per 1,000 exposures, compared with 5.77 injuries per 1,000 exposures in flag football. While tackle football players reported concussions at a slightly higher rate, the difference with flag players wasn’t statistically significant.

Dr. Peterson theorizes that tackle football players suffer concussions individually, whereas in flag football, concussions often result from two people running into each other. Looking at the injury logs, he noticed, “concussions seemed to come in pairs in the flag league.”

Overgrowth in Certain Brain Areas Associated With Autism

Wednesday, February 15th, 2017

Autism is associated with overgrowth in certain brain areas:

The study, led by scientists at University of North Carolina, Chapel Hill, and published in Nature, focused on 106 high-risk infants—those with autistic older siblings—and 42 low-risk babies. Researchers imaged the babies’ brains at 6, 12 and 24 months of age. Diagnoses of autism usually take place around age 2.

Of the 106 high-risk infants with brain scan at all three time points, 15 went on to develop autism. Their scans showed that by 12 months, there was significant overgrowth in several brain areas, including those involved in communication and in processing sensory information, compared with infants in the low-risk group and high-risk kids who weren’t later diagnosed with autism.

Is Romantic Kissing A Human Universal?

Tuesday, February 14th, 2017

In a recent study, less than half of the cultures the researchers sampled engaged in romantic kissing:

We looked at 168 cultures and found couples kissing in only 46 percent of them. Societies with distinct social classes are usually kissers; societies with fewer or no social classes, like hunter-gatherer communities, are usually not. For some, kissing seems unpleasant, unclean, or just plain weird. Kissing is clearly a culturally variable display of affection.

No one knows the exact origins of the romantic kiss. Some say it evolved to help test potential partners’ health through taste, their genetic compatibility through the smell of their immune system, or their romantic interest and sexual compatibility. Alternatively, it might have evolved from “kiss feeding” — the practice of a mother chewing up food and pushing it into her infant’s mouth with her tongue. The earliest known reference to kissing is in the Vedas, a 3,500-year-old Sanskrit scripture. Many classical societies, including the Romans, were passionate about kissing.

At least 90 percent of today’s cultures have kissing of one type or another, but the majority of it is parents kissing their children. Far less is known about patterns of who kisses romantically and who does not, and why.

Shakespeare in the Bush

Monday, February 13th, 2017

Off and on from 1949 to 1953 Laura Bohannan and her husband lived among the Tiv tribe of southeastern Nigeria. After the harvest and before the planting season, the swamps rise, and during this period of enforced isolation, she found herself reading Hamlet, while the tribe spent their days drinking maize and millet beer and singing and telling stories:

“You should sit and drink with us more often. Your servants tell me that when you are not with us, you sit inside your hut looking at a paper.”

The old man was acquainted with four kinds of “papers”: tax receipts, bride price receipts, court fee receipts, and letters. [...] I did not wish them to think me silly enough to look at any such papers for days on end, and I hastily explained that my “paper” was one of the “things of long ago” of my country.

“Ah,” said the old man. “Tell us.” I protested that I was not a storyteller. Storytelling is a skilled art among them; their standards are high, and the audiences critical — and vocal in their criticism. I protested in vain. This morning they wanted to hear a story while they drank. They threatened to tell me no more stories until I told them one of mine. Finally, the old man promised that no one would criticize my style, “for we know you are struggling with our language.” “But,” put in one of the elders, “you must explain what we do not understand, as we do when we tell you our stories.” Realizing that here was my chance to prove Hamlet universally intelligible, I agreed.

The old man handed me some more beer to help me on with my storytelling. Men filled their long wooden pipes and knocked coals from the fire to place in the pipe bowls; then, puffing contentedly, they sat back to listen. I began in the proper style, “Not yesterday, not yesterday, but long ago, a thing occurred. One night three men were keeping watch outside the homestead of the great chief, when suddenly they saw the former chief approach them.”

“Why was he no longer their chief?”

“He was dead,” I explained. “That is why they were troubled and afraid when they saw him.”

“Impossible,” began one of the elders, handing his pipe on to his neighbor, who interrupted, “Of course it wasn’t the dead chief. It was an omen sent by a witch. Go on.”

Slightly shaken, I continued. “One of these three was a man who knew things” — the closest translation for scholar, but unfortunately it also meant witch. The second elder looked triumphantly at the first. “So he spoke to the dead chief saying, ‘Tell us what we must do so you may rest in your grave,’ but the dead chief did not answer. He vanished, and they could see him no more. Then the man who knew things — his name was Horatio — said this event was the affair of the dead chief’s son, Hamlet.”

There was a general shaking of heads round the circle. “Had the dead chief no living brothers? Or was this son the chief?”

“No,” I replied. “That is, he had one living brother who became the chief when the elder brother died.”

The old men muttered: such omens were matters for chiefs and elders, not for youngsters; no good could come of going behind a chief’s back; clearly Horatio was not a man who knew things.

“Yes, he was,” I insisted, shooing a chicken away from my beer. “In our country the son is next to the father. The dead chief’s younger brother had become the great chief. He had also married his elder brother’s widow only about a month after the funeral.”

“He did well,” the old man beamed and announced to the others, “I told you that if we knew more about Europeans, we would find they really were very like us. In our country also,” he added to me, “the younger brother marries the elder brother’s widow and becomes the father of his children. Now, if your uncle, who married your widowed mother, is your father’s full brother, then he will be a real father to you. Did Hamlet’s father and uncle have one mother?”

His question barely penetrated my mind; I was too upset and thrown too far off-balance by having one of the most important elements of Hamlet knocked straight out of the picture. Rather uncertainly I said that I thought they had the same mother, but I wasn’t sure — the story didn’t say. The old man told me severely that these genealogical details made all the difference and that when I got home I must ask the elders about it. He shouted out the door to one of his younger wives to bring his goatskin bag.

Determined to save what I could of the mother motif, I took a deep breath and began again. “The son Hamlet was very sad because his mother had married again so quickly. There was no need for her to do so, and it is our custom for a widow not to go to her next husband until she has mourned for two years.”

“Two years is too long,” objected the wife, who had appeared with the old man’s battered goatskin bag. “Who will hoe your farms for you while you have no husband?”

“Hamlet,” I retorted, without thinking, “was old enough to hoe his mother’s farms himself. There was no need for her to remarry.” No one looked convinced. I gave up. “His mother and the great chief told Hamlet not to be sad, for the great chief himself would be a father to Hamlet. Furthermore, Hamlet would be the next chief: therefore he must stay to learn the things of a chief. Hamlet agreed to remain, and all the rest went off to drink beer.”

While I paused, perplexed at how to render Hamlet’s disgusted soliloquy to an audience convinced that Claudius and Gertrude had behaved in the best possible manner, one of the younger men asked me who had married the other wives of the dead chief.

“He had no other wives,” I told him.

“But a chief must have many wives! How else can he brew beer and prepare food for all his guests?”

I said firmly that in our country even chiefs had only one wife, that they had servants to do their work, and that they paid them from tax money.

It was better, they returned, for a chief to have many wives and sons who would help him hoe his farms and feed his people; then everyone loved the chief who gave much and took nothing — taxes were a bad thing.

I agreed with the last comment, but for the rest fell back on their favorite way of fobbing off my questions: “That is the way it is done, so that is how we do it.”

I decided to skip the soliloquy. Even if Claudius was here thought quite right to marry his brother’s widow, there remained the poison motif, and I knew they would disapprove of fratricide. More hopefully I resumed, “That night Hamlet kept watch with the three who had seen his dead father. The dead chief again appeared, and although the others were afraid, Hamlet followed his dead father off to one side. When they were alone, Hamlet’s dead father spoke.”

“Omens can’t talk!” The old man was emphatic.

“Hamlet’s dead father wasn’t an omen. Seeing him might have been an omen, but he was not.” My audience looked as confused as I sounded. “It was Hamlet’s dead father. It was a thing we call a ‘ghost.’” I had to use the English word, for unlike many of the neighboring tribes, these people didn’t believe in the survival after death of any individuating part of the personality.

“What is a ‘ghost?’ An omen?”

“No, a ‘ghost’ is someone who is dead but who walks around and can talk, and people can hear him and see him but not touch him.”

They objected. “One can touch zombis.”

“No, no! It was not a dead body the witches had animated to sacrifice and eat. No one else made Hamlet’s dead father walk. He did it himself.”

“Dead men can’t walk,” protested my audience as one man.

I was quite willing to compromise.

“A ‘ghost’ is the dead man’s shadow.”

But again they objected. “Dead men cast no shadows.”

“They do in my country,” I snapped.

The old man quelled the babble of disbelief that arose immediately and told me with that insincere, but courteous, agreement one extends to the fancies of the young, ignorant, and superstitious, “No doubt in your country the dead can also walk without being zombis.” From the depths of his bag he produced a withered fragment of kola nut, bit off one end to show it wasn’t poisoned, and handed me the rest as a peace offering.

“Anyhow,” I resumed, “Hamlet’s dead father said that his own brother, the one who became chief, had poisoned him. He wanted Hamlet to avenge him. Hamlet believed this in his heart, for he did not like his father’s brother.” I took another swallow of beer. “In the country of the great chief, living in the same homestead, for it was a very large one, was an important elder who was often with the chief to advise and help him. His name was Polonius. Hamlet was courting his daughter, but her father and her brother . . . [I cast hastily about for some tribal analogy] warned her not to let Hamlet visit her when she was alone on her farm, for he would be a great chief and so could not marry her.”

“Why not?” asked the wife, who had settled down on the edge of the old man’s chair. He frowned at her for asking stupid questions and growled, “They lived in the same homestead.”

“That was not the reason,” I informed them. “Polonius was a stranger who lived in the homestead because he helped the chief, not because he was a relative.”

“Then why couldn’t Hamlet marry her?”

“He could have,” I explained, “but Polonius didn’t think he would. After all, Hamlet was a man of great importance who ought to marry a chief’s daughter, for in his country a man could have only one wife. Polonius was afraid that if Hamlet made love to his daughter, then no one else would give a high price for her.”

“That might be true,” remarked one of the shrewder elders, “but a chief’s son would give his mistress’s father enough presents and patronage to more than make up the difference. Polonius sounds like a fool to me.”

“Many people think he was,” I agreed. “Meanwhile Polonius sent his son Laertes off to Paris to learn the things of that country, for it was the homestead of a very great chief indeed. Because he was afraid that Laertes might waste a lot of money on beer and women and gambling, or get into trouble by fighting, he sent one of his servants to Paris secretly, to spy out what Laertes was doing. One day Hamlet came upon Polonius’s daughter Ophelia. He behaved so oddly he frightened her. Indeed” — I was fumbling for words to express the dubious quality of Hamlet’s madness — “the chief and many others had also noticed that when Hamlet talked one could understand the words but not what they meant. Many people thought that he had become mad.” My audience suddenly became much more attentive. “The great chief wanted to know what was wrong with Hamlet, so he sent for two of Hamlet’s age mates [school friends would have taken a long explanation] to talk to Hamlet and find out what troubled his heart. Hamlet, seeing that they had been bribed by the chief to betray him, told them nothing. Polonius, however, insisted that Hamlet was mad because he had been forbidden to see Ophelia, whom he loved.”

“Why,” inquired a bewildered voice, “should anyone bewitch Hamlet on that account?”

“Bewitch him?”

“Yes, only witchcraft can make anyone mad, unless, of course, one sees the beings that lurk in the forest.”

I stopped being a storyteller and took out my notebook and demanded to be told more about these two causes of madness. Even while they spoke and I jotted notes, I tried to calculate the effect of this new factor on the plot. Hamlet had not been exposed to the beings that lurk in the forests. Only his relatives in the male line could bewitch him. Barring relatives not mentioned by Shakespeare, it had to be Claudius who was attempting to harm him. And, of course, it was.

For the moment I staved off questions by saying that the great chief also refused to believe that Hamlet was mad for the love of Ophelia and nothing else. “He was sure that something much more important was troubling Hamlet’s heart.”

“Now Hamlet’s age mates,” I continued, “had brought with them a famous storyteller. Hamlet decided to have this man tell the chief and all his homestead a story about a man who had poisoned his brother because he desired his brother’s wife and wished to be chief himself. Hamlet was sure the great chief could not hear the story without making a sign if he was indeed guilty, and then he would discover whether his dead father had told him the truth.”

The old man interrupted, with deep cunning, “Why should a father lie to his son?” he asked.

I hedged: “Hamlet wasn’t sure that it really was his dead father.” It was impossible to say anything, in that language, about devil-inspired visions.

“You mean,” he said, “it actually was an omen, and he knew witches sometimes send false ones. Hamlet was a fool not to go to one skilled in reading omens and divining the truth in the first place. A man-who-sees-the-truth could have told him how his father died, if he really had been poisoned, and if there was witchcraft in it; then Hamlet could have called the elders to settle the matter.”

The shrewd elder ventured to disagree. “Because his father’s brother was a great chief, one-who-sees-the-truth might therefore have been afraid to tell it. I think it was for that reason that a friend of Hamlet’s father — a witch and an elder — sent an omen so his friend’s son would know. Was the omen true?”

“Yes,” I said, abandoning ghosts and the devil; a witch-sent omen it would have to be. “It was true, for when the storyteller was telling his tale before all the homestead, the great chief rose in fear. Afraid that Hamlet knew his secret he planned to have him killed.”

The stage set of the next bit presented some difficulties of translation. I began cautiously. “The great chief told Hamlet’s mother to find out from her son what he knew. But because a woman’s children are always first in her heart, he had the important elder Polonius hide behind a cloth that hung against the wall of Hamlet’s mother’s sleeping hut. Hamlet started to scold his mother for what she had done.”

There was a shocked murmur from everyone. A man should never scold his mother.

“She called out in fear, and Polonius moved behind the cloth. Shouting, ‘A rat!’ Hamlet took his machete and slashed through the cloth.” I paused for dramatic effect. “He had killed Polonius.”

The old men looked at each other in supreme disgust. “That Polonius truly was a fool and a man who knew nothing! What child would not know enough to shout, ‘It’s me!’” With a pang, I remembered that these people are ardent hunters, always armed with bow, arrow, and machete; at the first rustle in the grass an arrow is aimed and ready, and the hunter shouts “Game!” If no human voice answers immediately, the arrow speeds on its way. Like a good hunter, Hamlet had shouted, “A rat!”

I rushed in to save Polonius’s reputation. “Polonius did speak. Hamlet heard him. But he thought it was the chief and wished to kill him to avenge his father. He had meant to kill him earlier that evening….” I broke down, unable to describe to these pagans, who had no belief in individual afterlife, the difference between dying at one’s prayers and dying “unhousell’d, disappointed, unaneled.”

This time I had shocked my audience seriously. “For a man to raise his hand against his father’s brother and the one who has become his father — that is a terrible thing. The elders ought to let such a man be bewitched.”

I nibbled at my kola nut in some perplexity, then pointed out that after all the man had killed Hamlet’s father.

“No,” pronounced the old man, speaking less to me than to the young men sitting behind the elders. “If your father’s brother has killed your father, you must appeal to your father’s age mates: they may avenge him. No man may use violence against his senior relatives.” Another thought struck him. “But if his father’s brother had indeed been wicked enough to bewitch Hamlet and make him mad that would be a good story indeed, for it would be his fault that Hamlet, being mad, no longer had any sense and thus was ready to kill his father’s brother.”

There was a murmur of applause. Hamlet was again a good story to them, but it no longer seemed quite the same story to me. As I thought over the coming complications of plot and motive, I lost courage and decided to skim over dangerous ground quickly.

“The great chief,” I went on, “was not sorry that Hamlet had killed Polonius. It gave him a reason to send Hamlet away, with his two treacherous age mates, with letters to a chief of a far country, saying that Hamlet should be killed. But Hamlet changed the writing on their papers, so that the chief killed his age mates instead.” I encountered a reproachful glare from one of the men whom I had told undetectable forgery was not merely immoral but beyond human skill. I looked the other way.

“Before Hamlet could return, Laertes came back for his father’s funeral. The great chief told him Hamlet had killed Polonius. Laertes swore to kill Hamlet because of this, and because his sister Ophelia, hearing her father had been killed by the man she loved, went mad and drowned in the river.”

“Have you already forgotten what we told you?” The old man was reproachful. “One cannot take vengeance on a madman; Hamlet killed Polonius in his madness. As for the girl, she not only went mad, she was drowned. Only witches can make people drown. Water itself can’t hurt anything. It is merely something one drinks and bathes in.”

I began to get cross. “If you don’t like the story, I’ll stop.”

The old man made soothing noises and himself poured me some more beer. “You tell the story well, and we are listening. But it is clear that the elders of your country have never told you what the story really means. No, don’t interrupt! We believe you when you say your marriage customs are different, or your clothes and weapons. But people are the same everywhere; therefore, there are always witches and it is we, the elders, who know how witches work. We told you it was the great chief who wished to kill Hamlet, and now your own words have proved us right. Who were Ophelia’s male relatives?”

“There were only her father and her brother.” Hamlet was clearly out of my hands.

“There must have been many more; this also you must ask of your elders when you get back to your country. From what you tell us, since Polonius was dead, it must have been Laertes who killed Ophelia, although I do not see the reason for it.”

We had emptied one pot of beer, and the old men argued the point with slightly tipsy interest. Finally one of them demanded of me, “What did the servant of Polonius say on his return?”

With difficulty I recollected Reynaldo and his mission. “I don’t think he did return before Polonius was killed.”

“Listen,” said the elder, “and I will tell you how it was and how your story will go, then you may tell me if I am right. Polonius knew his son would get into trouble, and so he did. He had many fines to pay for fighting, and debts from gambling. But he had only two ways of getting money quickly. One was to marry off his sister at once, but it is difficult to find a man who will marry a woman desired by the son of a chief. For if the chief’s heir commits adultery with your wife, what can you do? Only a fool calls a case against a man who will someday be his judge. Therefore Laertes had to take the second way: he killed his sister by witchcraft, drowning her so he could secretly sell her body to the witches.”

I raised an objection. “They found her body and buried it. Indeed Laertes jumped into the grave to see his sister once more — so, you see, the body was truly there. Hamlet, who had just come back, jumped in after him.”

“What did I tell you?” The elder appealed to the others. “Laertes was up to no good with his sister’s body. Hamlet prevented him, because the chief’s heir, like a chief, does not wish any other man to grow rich and powerful. Laertes would be angry, because he would have killed his sister without benefit to himself. In our country he would try to kill Hamlet for that reason. Is this not what happened?”

“More or less,” I admitted. “When the great chief found Hamlet was still alive, he encouraged Laertes to try to kill Hamlet and arranged a fight with machetes between them. In the fight both the young men were wounded to death. Hamlet’s mother drank the poisoned beer that the chief meant for Hamlet in case he won the fight. When he saw his mother die of poison, Hamlet, dying, managed to kill his father’s brother with his machete.”

“You see, I was right!” exclaimed the elder.

“That was a very good story,” added the old man, “and you told it with very few mistakes.” There was just one more error, at the very end. The poison Hamlet’s mother drank was obviously meant for the survivor of the fight, whichever it was. If Laertes had won, the great chief would have poisoned him, for no one would know that he arranged Hamlet’s death. Then, too, he need not fear Laertes’ witchcraft; it takes a strong heart to kill one’s only sister by witchcraft.

“Sometime,” concluded the old man, gathering his ragged toga about him, “you must tell us some more stories of your country. We, who are elders, will instruct you in their true meaning, so that when you return to your own land your elders will see that you have not been sitting in the bush, but among those who know things and who have taught you wisdom.”

Introductory psychology textbooks lean left

Wednesday, February 8th, 2017

Introductory psychology textbooks lean left:

Writing in Current Psychology, Christopher Ferguson at Stetson University and his colleagues at Texas A&M International University conclude that intro textbooks often have difficulty covering controversial topics with care, and that whether intentionally or not, they are frequently presenting students with a liberal-leaning, over-simplified perspective, as well propagating or failing to challenge myths and urban legends.

[...]

Ferguson and his team examined textbook coverage of seven areas of research consisting of findings which might be considered particularly appealing or unappealing to textbook authors with liberal leanings, and/or which could be prone to alarmist interpretation. This included research on whether media violence incites aggression; the stereotype threat (the notion that performance differences between groups are exaggerated by the fear of conforming to stereotypes); the narcissism epidemic (the idea that today’s youth are more narcissistic than youth in the past); that smacking/spanking children leads to aggression and other negative outcomes; that there are multiple intelligences; that human behaviour is explained by evolutionary theories related to mate selection and sexual competition (in this case, the authors assumed liberal authors would prefer not to cover this research); and controversy around antidepressant medication.

The researchers looked to see if textbook authors presented the evidence as more definitive than it is in these areas, or only presented one side of the arguments. They found that there was biased treatment of media violence and stereotype threat by half or more of the books, and of multiple intelligences and spanking by a third. A quarter of books failed to deal with controversy around antidepressants. Evolutionary theories were neglected by a fifth of the books and presented in biased fashion by one quarter. “We believe that these errors are consistent with an indoctrination, however intentional, into certain beliefs or hypotheses that may be ‘dear’ to a socio-politically homogenous psychological community,” Ferguson and his colleagues said.

They also looked at textbook treatment of various psychology myths and urban legends, including the frequently exaggerated story of the murder of Kitty Genovese, which is often cited as a perfect example of the “bystander effect”: our reduced likelihood of intervening to help when in the company of a greater number of other people who could help. Nearly half the books perpetuated the myth that 33 witnesses watched the killing of Genovese without doing anything to help her. Meanwhile, nearly three quarters of the books failed to challenge the popular misconception that we only use ten per cent of our brains, or that listening to Mozart makes us smarter. And 70 per cent of the books gave the French neurologist Paul Broca undue credit for localising speech function in the brain: the researchers say that the theory of the cortical localisation of speech was first put forward by Ernest Auburtin. “It is surprising to see so few textbooks addressing common misconceptions about psychology,” they said.

[...]

After all, in recent years, we’ve also covered research by Richard Griggs at Florida State University that’s found biased textbook treatment of Milgram’s classic studies on obedience, outdated accounts of the story of Phineas Gage, biased coverage of Asch’s studies of conformity, and of Zimbardo’s Stanford Prison Experiment. Psychology students: if you’re looking for a rounded and accurate introduction to the field , you could consider supplementing your textbook reading with regular visits to our Research Digest blog. Or maybe you do that already.

Shell shock after all

Tuesday, February 7th, 2017

Scientists assumed that explosive blasts affect the brain in much the same way as concussions from football or car accidents:

No one had done a systematic post-mortem study of blast-injured troops. That was exactly what the Pentagon asked Perl to do in 2010, offering him access to the brains they had gathered for research. It was a rare opportunity, and Perl left his post as director of neuropathology at the medical school at Mount Sinai to come to Washington.

Perl and his lab colleagues recognized that the injury that they were looking at was nothing like concussion. The hallmark of C.T.E. is an abnormal protein called tau, which builds up, usually over years, throughout the cerebral cortex but especially in the temporal lobes, visible across the stained tissue like brown mold. What they found in these traumatic-brain-injury cases was totally different: a dustlike scarring, often at the border between gray matter (where synapses reside) and the white matter that interconnects it. Over the following months, Perl and his team examined several more brains of service members who died well after their blast exposure, including a highly decorated Special Operations Forces soldier who committed suicide. All of them had the same pattern of scarring in the same places, which appeared to correspond to the brain’s centers for sleep, cognition and other classic brain-injury trouble spots.

Then came an even more surprising discovery. They examined the brains of two veterans who died just days after their blast exposure and found embryonic versions of the same injury, in the same areas, and the development of the injuries seemed to match the time elapsed since the blast event. Perl and his team then compared the damaged brains with those of people who suffered ordinary concussions and others who had drug addictions (which can also cause visible brain changes) and a final group with no injuries at all. No one in these post-mortem control groups had the brown-dust pattern.

Perl’s findings, published in the scientific journal The Lancet Neurology, may represent the key to a medical mystery first glimpsed a century ago in the trenches of World War I. It was first known as shell shock, then combat fatigue and finally PTSD, and in each case, it was almost universally understood as a psychic rather than a physical affliction.

[...]

A blast begins simply: A detonator turns a lump of solid matter into a deadly fireball. Within that moment, three distinct things happen. The first is the blast wave, a wall of static pressure traveling outward in all directions faster than the speed of sound. Next, a blast wind fills the void and carries with it any objects it encounters. This is the most manifestly destructive part of the blast, capable of hurling cars, people and shrapnel against buildings and roadsides. The remaining effects include fire and toxic gases, which can sear, poison and asphyxiate anyone within range.

The effects of all of this on the human body are myriad and more complicated than the blast itself. People who have been exposed to blasts at close range usually describe it as an overpowering, full-body experience unlike anything they have ever known. Many soldiers do not recall the moment of impact: it gets lost in the flash of light, the deafening sound or unconsciousness. Those who do remember it often speak of a simultaneous punching and squeezing effect, a feeling at once generalized and intensely violent, as if someone had put a board against your body and then struck it with dozens of hammers.

[...]

Very quickly [after WWI began], soldiers began emerging with bizarre symptoms; they shuddered and gibbered or became unable to speak at all. Many observers were struck by the apparent capacity of these blasts to kill and maim without leaving any visible trace. The British journalist Ellis Ashmead-Bartlett famously described the sight of seven Turks at Gallipoli in 1915, sitting together with their rifles across their knees: “One man has his arm across the neck of his friend and a smile on his face as if they had been cracking a joke when death overwhelmed them. All now have the appearance of being merely asleep; for of the several I can only see one who shows any outward injury.”

For those who survived a blast and suffered the mysterious symptoms, soldiers quickly coined their own phrase: shell shock.

[...]

One British doctor, Frederick Mott, believed the shock was caused by a physical wound and proposed dissecting the brains of men who suffered from it. He even had some prescient hunches about the mechanism of blast’s effects: the compression wave, the concussion and the toxic gases. In a paper published in The Lancet in February 1916, he posited a “physical or chemical change and a break in the links of the chain of neurons which subserve a particular function.” Mott might not have seen anything abnormal in the soldiers’ brains, even if he had examined them under a microscope; neuropathology was still in its infancy. But his prophetic intuitions made him something of a hero to Perl.

Mott’s views were soon eclipsed by those of other doctors who saw shell shock more as a matter of emotional trauma. This was partly a function of the intellectual climate; Freud and other early psychologists had recently begun sketching provocative new ideas about how the mind responds to stress.

[...]

Cernak became convinced [after the Balkans conflict of the 1990s] that blast ripples through the body like rings on a pond’s surface. Its speed changes when it encounters materials of different density, like air pockets or the border between the brain’s gray and white matter, and can inflict greater damage in those places. As it happens, physicists would later theorize some very similar models for how blast damages the brain. Several possibilities have now been explored, including surges of blood upward from the chest; shearing loads on brain tissue; and the brain bouncing back and forth inside the skull, as happens with concussion. Charles Needham, a renowned authority on blast physics, told me post-mortems on blast injuries have lent some support to all of those theories, and the truth may be that several are at play simultaneously.

A decade after her initial battlefield surveys in the Balkans, Cernak took a position at Johns Hopkins University in Baltimore, where she did animal research that bolstered her conviction about blast’s full-body effects. She found that even if an animal’s head is protected during a blast, the brain can sustain damage, because the blast wave transfers through the body via blood and tissue. Cernak also came to believe that blast injuries to the brain were cumulative and that even small explosions with no discernible effects could, if repeated, produce terrible and irreversible damage. Much of this would later be confirmed by other scientists.

This all sounds quite credible — but it doesn’t explain the many cases of PTSD from troops who never faced combat or suffered blast injuries.

Parasites and Piety

Sunday, February 5th, 2017

In This Is Your Brain on Parasites, Kathleen McAuliffe examines how tiny creatures manipulate our behavior and shape society, with a chapter on parasites and piety. One passage recalls Chapter 4 of John Durant’s Paleo Manifesto, “Moses the Microbiologist”:

It took thousands of years for agriculture to take off. Few cities in the Middle East, where the movement began, had more than 50,000 inhabitants prior to biblical times. So the perfect storm was slow to gather but, when it hit, a health crisis of unimaginable disruption and trauma ensued. These new diseases were far more lethal and terrifying than the versions manifested in the untreated and unvaccinated today. We are the heirs of exceptionally hardy people who were unusual in having immune systems that could repel these virulent germs. Those at the forefront of these epidemics likely fared far worse on average than our more recent ancestors. Consider the fate that awaited some of the first people to get syphilis: pustules popped up on their skin from their heads to their knees, then their flesh began to fall off their bodies, and within three months they were dead. Those lucky enough to survive the ravages of never-before-encountered germs rarely came away unscathed. Many were crippled, paralysed, disfigured, blinded or otherwise maimed.

It was exactly at this critical juncture that our forefathers went from being not particularly spiritual to embracing religion — and not just passing fads, but some of the most widely followed faiths in the world today, whose gods promised to reward the good and punish the evil. One of the oldest of these belief systems is Judaism, whose most hallowed prophet, Moses, is equally revered in Christianity and in Islam (in the Quran, he goes by the name Musa and is referred to more times than Muhammad). Half the world’s population follows religions derived from Mosaic Law — that is, God’s commandments as communicated to Moses.

Not surprisingly, given its vintage, Mosaic Law is obsessed with matters related to cleanliness and lifestyle factors that we now know play a key role in the spread of disease. Just as villages in the Fertile Crescent were giving rise to filthy, crowded cities, and outbreaks of illness were becoming an everyday horror, Mosaic Law decreed that Jewish priests should wash their hands — to this day, one of the most effective public-health measures known to science.

The Torah contains much more medical wisdom — not merely its famous admonishments to avoid eating pork (a source of trichinosis, a parasitic disease caused by a roundworm) and shellfish (filter feeders that concentrate contaminants), and to circumcise sons (bacteria can collect under the foreskin flap). Jews were instructed to bathe on the Sabbath (every Saturday); cover their wells (which kept out vermin and insects); engage in cleansing rituals if exposed to bodily fluids; quarantine people with leprosy and other skin diseases and, if infection persisted, burn that person’s clothes; bury the dead quickly before corpses decomposed; submerge dishes and eating utensils in boiling water after use; never consume the flesh of an animal that had died of natural causes (as it might have been felled by illness) or eat meat more than two days old (likely on the verge of turning rancid).

When it came time for divvying up the spoils of war, Jewish doctrine required any metal booty that could withstand intense heat — objects made of gold, silver, bronze or tin — to ‘be put through fire’ (sterilised by high temperatures). What could not endure fire was to be washed with ‘purifying water’: a mixture of water, ash and animal fat: an early soap recipe.

Equally prescient from the standpoint of modern disease control, Mosaic Law has numerous injunctions specifically related to sex. Parents were admonished not to allow their daughters to become prostitutes, and premarital sex, adultery, male homosexuality and bestiality were all discouraged, if not banned outright.

People just give up trying to improve

Thursday, February 2nd, 2017

Anders Ericsson — of deliberate practice fame — began his career helping to push the boundaries of working memory:

Most people can repeat back a seven-digit phone number, but not a ten-digit one. He recruited Steve Faloon, an average Carnegie Mellon University student, and they set about systematically working to get better. After about 200 hours of effort, Faloon could repeat back 82 digits, by far a world record at the time. Faloon wasn’t destined for such greatness. Rather, Ericsson’s takeaway is that performance has no inherent limit. “Instead, I’ve found that people more often just give up and stop trying to improve,” he writes. Work constantly at the edge of your ability, though, and your brain changes in a way that makes better performance possible.

Schizophrenic Attackers

Tuesday, January 31st, 2017

Dr. Jeroen Ensink, 41, a lecturer at the London School of Hygiene and Tropical Medicine, was stabbed to death by Nigerian-born student Femi Nandap, who was a cannabis-abusing psychotic (in the strict, clinical sense):

Despite attacking a police officer in May last year and then being caught in possession of two kitchen knives, Nandap was twice given bail, before prosecutors decided to drop the charges against him.

Six days later he attacked and killed Dr Ensink, telling police who tried to intervene that he was the “black messiah”.

The current academic wisdom is that it would be impossible to prevent such murders without restricting large numbers of patients — say 35,000 of them:

Taking the very paper which provides the “35,000” figure for stranger murder, the figures for assault are shown below, and put things into a more manageable context. The annual rates for assault and violent crime are extraordinarily high, almost unbelievably so. Given the very high base rate, screening and monitoring are worth while.

Positive Predictive Value for the Detection of Adverse Events in Schizophrenia

As the event becomes more rare, the positive predictive value of the risk-categorization becomes lower, and the error rate higher, with progressively more people needing to be monitored to prevent one rare event. However, to prevent an assault would require that 3 schizophrenic patients be monitored, calling them in to check they are taking their medication, and presumably (hardest part) searching for them if they failed to show up. Easier would be to link up with the Police, so that if a patient is brought in for violent behaviour of any sort there can be coordinated management of the offender. Devoutly to be wished, often denied, but in the manageable range given the will and the resources. It would provide a good service for the patients, reducing suicide attempts, improving the quality of their lives, and reducing threats to others. It would certainly be worth testing it out in a London Borough, and checking that the above figures, derived from the best sources, hold up on further examination.

None of the media coverage goes into the question which arises out of normal curiosity: is psychotic behaviour more common among Africans in the UK? The picture above shows murderer and victim, and is an all too common pairing. The answer to the African question is: 6 to 9 times higher.

The very bottom 14% have very simple skills

Saturday, January 28th, 2017

If someone you know doubts intelligence differences, James Thompson says, show them the functional literacy data that Linda Gottfredson references:

That is right. Only 4% of the white population can do all the tasks in the list.

NALS Levels

21% get to the 4th level but cannot do carpet cost type problems, and at the very bottom 14% have very simple skills, which do not include locating an intersection on a street map. For many of you reading this, the finding will seem incredible. It is incredible. Human differences are hard to believe, but they are matters to be demonstrated, beliefs notwithstanding.

Allocating dwellings, schools, and health facilities without regard to social class had no effect

Thursday, January 26th, 2017

The city of Warsaw was razed at the end of World War II and rebuilt under a socialist government. As this 1978 Science paper notes, the socialist government’s policy of allocating dwellings, schools, and health facilities without regard to social class had no effect on the association of social and family factors with cognitive development:

Of the 14,238 children born in 1963 and living in Warsaw, 96 percent were given the Raven’s Progressive Matrices Test and an arithmetic and a vocabulary test in March to June of 1974. Information was collected on the families of the children, and on characteristics of schools and city districts. Parental occupation and education were used to form a family factor, and the district data were collapsed into two factors, one relating to social marginality, and the other to distance from city center. Analysis showed that the initial assumption of even distribution of family, school, and district attributes was reasonable. Mental performance was unrelated either to school or district factors; it was related to parental occupation and education in a strong and regular gradient. It is concluded that an egalitarian social policy executed over a generation failed to override the association of social and family factors with cognitive development that is characteristic of more traditional industrial societies.