Chimps are not superhumanly strong

Wednesday, June 28th, 2017

Chimps are not as superhumanly strong as we thought they were:

“There’s this idea out there that chimpanzees are superhuman strong,” says Matthew O’Neill at the University of Arizona in Phoenix. Yet his team’s experiments and computer models show that a chimpanzee muscle is only about a third stronger than a human one of the same size.

This result matches well with the few tests that have been done, which suggest that when it comes to pulling and jumping, chimps are about 1.5 times as strong as humans relative to their body mass. But because they are lighter than the average person, humans can actually outperform them in absolute terms, say O’Neill.

His findings suggest that other apes have similar muscle strength to chimpanzees. “Humans are the odd ones,” he says.

O’Neill’s team has been studying the evolution of upright walking. To create an accurate computer model of how chimps walk, the researchers needed to find out whether their muscles really are exceptionally strong. So they removed small samples of leg muscle from three chimps under general anaesthetic and measured the strength of individual fibres.

The same procedure is used to study human muscles. Comparing the results with the many studies on those revealed that, contrary to the claims of several other studies, there is nothing special about chimp muscle. “Chimpanzee muscle is really no different than human muscle in terms of the force that individual fibres exert,” says O’Neill.

So why, on a pound-for-pound basis, are chimps slightly stronger than humans? The team went on to look at the muscle of chimps that had died of natural causes, which revealed that two-thirds of their muscle consists of fast-twitch fibres, whereas more than half of human fibres are slow-twitch.

[...]

Quite how the myth that chimps are incredibly strong came about is not clear, says O’Neill. But it may have been fuelled by a 1923 study that claimed one chimp could pull nine times its own body weight. Later studies suggested they could only pull two to four times their weight.

Outer appearance simply can’t imply anything about inner character

Monday, June 26th, 2017

Blaise Aguera y Arcas leads Google’s Machine Intelligence group in Seattle, and he has written a remarkably unscientific piece decrying physiognomy’s new clothes:

The practice of using people’s outer appearance to infer inner character is called physiognomy. While today it is understood to be pseudoscience, the folk belief that there are inferior “types” of people, identifiable by their facial features and body measurements, has at various times been codified into country-wide law, providing a basis to acquire land, block immigration, justify slavery, and permit genocide. When put into practice, the pseudoscience of physiognomy becomes the pseudoscience of scientific racism.

Rapid developments in artificial intelligence and machine learning have enabled scientific racism to enter a new era, in which machine-learned models embed biases present in the human behavior used for model development. Whether intentional or not, this “laundering” of human prejudice through computer algorithms can make those biases appear to be justified objectively.

Outer appearance simply can’t imply anything about inner character. That would be wrong.

He goes on to cite a Chinese study that sounds (literally) incredible, but the case that machine-learning is being used to “launder” human biases is rather weak.

Wu and Zhang’s criminal images (top) and non-criminal images (bottom)

Sourdough is just white bread

Friday, June 9th, 2017

I would have assumed that sourdough bread and ordinary white bread were nutritionally very, very similar, but wild yeast strains and bacteria that fill sourdough with sour acids purportedly reduce its glycemic index. Or so scientists thought, until a recent study found otherwise:

In a study led by students Tal Korem and David Zeevi, the Israeli team picked two extremes from the bread world. They hired a local baker to prepare artisanal sourdough from whole-grain flour. They also bought mass-manufactured loaves of white bread, made from refined flour and loaded with preservatives.

The team recruited 20 volunteers and asked half to spend a week eating the white bread and another eating the sourdough. The other volunteers did the same in the reverse order. Before and after each bread-filled week, the team took a census of the bacteria in each volunteer’s gut, as well as measured 20 variables including blood pressure, weight, blood sugar, cholesterol, triglycerides, and various hormones. They found that the bread the participants ate had no significant effect on any of these factors. Even the microbiome, which can shift quickly and extensively after a change in diet, was barely affected by the choice of breads.

Weighted bats don’t quicken a batter’s swing

Monday, June 5th, 2017

The Wall Street Journal reports that weighted bats don’t quicken a batter’s swing — but we’ve known that for decades:

“With 20 college baseball players from one university, I found no difference,” said Dr. Szymanski, who referred to the number of players he studied with 10 differently weighted bats. “Their performance was statistically unchanged.”

Other studies, notably those by Dr. DeRenne, have found that warming up with an overloaded bat, especially with a doughnut, slowed down batters.

“The doughnut is the worst,” said Dr. DeRenne, who tested one weighing 28 ounces. “It changes the balance point in the bat.”

The weight may alter the batter’s swing, especially in younger players who are still developing strength and mechanics.

Sport Science, a television series where athletes and scientists explore the biomechanics of different sports activities, tested the effect with a college player in 2008. Without any added weight, the batter averaged 69 mph on 10 swings and routinely connected with the bat’s sweet spot on balls pitched from a machine. After warming up with a doughnut, the batter’s speed decreased to 68.3 mph on average, and on each swing, the ball missed the bat’s sweet spot by several inches.

The experience of a lone batter in a single test can’t be generalized to others, but the results resembled other studies.

Cannabis wards off dementia

Sunday, June 4th, 2017

Rather than dulling or impairing cognition, THC appears to reverse the aging process and improve mental processes:

To test the hypothesis, mice were given a small daily dose of THC over the course of one month at the age of 2 months, 12 months and again at 18 months of age. It is important to understand that mice typically live until 2 years old. The dose was small enough to avoid any psychoactive effects.

Tests assessed the animals’ learning, memory, orientation and recognition skills. Interestingly, 18-month-old mice given THC demonstrated cognitive skills equal to 2-month-old controls, while the placebo group suffered cognitive deterioration associated with normal aging.

According to one of the authors, neurobiology professor Andreas Zimmer, University of Bonn, “The treatment completely reversed the loss of performance in the old animals. We repeated these experiments many times. It’s a very robust and profound effect.” Even more remarkable, gene activity and the molecular profile in the brain tissue was that of much younger animals. Specifically, neurons in the hippocampus grew more synaptic spines — points of contact necessary for communication between neurons.

(Almost) Everything he learned about science he learned from Isaac Asimov

Saturday, June 3rd, 2017

(Almost) everything he learned about science he learned from Isaac Asimov, Jamie Todd Rubin says:

I never learned about the Germinid meteor shower in any of my schooling. Instead, I learned about it and about meteor showers in general through Isaac Asimov’s science essays that appeared monthly in The Magazine of Fantasy & Science Fiction. The first of Asimov’s science essays appeared in the November 1958 issue (of which I happen to posses a copy).

Those monthly science columns continued unabated for 399 consecutive months. (And eventually, Isaac’s wife, Janet, put together a 400th column after his death.) The essays were collected in more than two dozen books. The columns themselves ranged through all realms of science, and occasionally into philosophy and humanities. They were written in Asimov’s familiar colloquial style, making it easy for anyone to approach even arcane subjects. I devoured every one of those essays and it is from those essays that I truly believe that I learned nearly everything I know about science today.

[...]

Asimov’s essays taught me not only the hows and whys of science, they taught me the history of science. Taken together, anyone who reads all 399 F&SF science essays can’t miss certain patterns in logic and reasoning, can’t miss the evolution of thought and experiment. The essays taught me that scientists were real men and women.

[...]

Today, only a few of these essays are truly dated. Some facts have changed because science evolves, but the core is still valid and the history that these essays provides is an invaluable tool for understanding the cumulative nature of science. Seven of these early essays were never put into any collections, and there were six or seven that Asimov wrote before his death that have not, to my knowledge, been collected either. Perhaps I am a lone voice in the wilderness here, but I think it’s high time that a newly reissued compendium of all of Isaac Asimov’s F&SF science essays be put together and re-released.

I was shocked to find that Amazon’s Isaac Asimov page doesn’t list any nonfiction, at least not until the second page, where Understanding Physics shows up. It’s out of print.

Asimov’s New Guide To Science is the book that came to mind when Rubin mentioned the history of science. I had that same experience of finding historical context really, really illuminating.

Hungarians have consistently proved good at odd things

Monday, May 29th, 2017

I remember a short anecdote from By the Sword: A History of Gladiators, Musketeers, Samurai, Swashbucklers, used to make the point that “Hungarians have consistently proved good at odd things”:

In the early 1950s the scientific advisory board of the U.S. Atomic Energy Commission convened in Washington D.C. A first count of the members showed a minority absent, but still a quorum; another count enabled the chairman to ask his colleagues, in his faultless native Hungarian, “Shall we conduct this meeting in the mother tongue?” Agreed and done.

Imagine the future or retouch the past

Monday, May 29th, 2017

We aren’t so much wise, as the name Homo sapiens would suggest, but unusually forward-looking, Martin E.P. Seligman and John Tierney argue. We’re really Homo prospectus:

This link between memory and prospection has emerged in research showing that people with damage to the brain’s medial temporal lobe lose memories of past experiences as well as the ability to construct rich and detailed simulations of the future. Similarly, studies of children’s development show that they’re not able to imagine future scenes until they’ve gained the ability to recall personal experiences, typically somewhere between the ages of 3 and 5.

Perhaps the most remarkable evidence comes from recent brain imaging research. When recalling a past event, the hippocampus must combine three distinct pieces of information — what happened, when it happened and where it happened — that are each stored in a different part of the brain. Researchers have found that the same circuitry is activated when people imagine a novel scene. Once again, the hippocampus combines three kinds of records (what, when and where), but this time it scrambles the information to create something new.

Even when you’re relaxing, your brain is continually recombining information to imagine the future, a process that researchers were surprised to discover when they scanned the brains of people doing specific tasks like mental arithmetic. Whenever there was a break in the task, there were sudden shifts to activity in the brain’s “default” circuit, which is used to imagine the future or retouch the past.

This discovery explains what happens when your mind wanders during a task: It’s simulating future possibilities. That’s how you can respond so quickly to unexpected developments. What may feel like a primitive intuition, a gut feeling, is made possible by those previous simulations.

The atomic bomb was basically a Hungarian high school science fair project

Sunday, May 28th, 2017

The Atomic Bomb could be considered a Hungarian high school science fair project:

A group of Manhattan Project physicists created a tongue-in-cheek mythology where superintelligent Martian scouts landed in Budapest in the late 19th century and stayed for about a generation, after which they decided the planet was unsuitable for their needs and disappeared. The only clue to their existence were the children they had with local women.

The joke was that this explained why the Manhattan Project was led by a group of Hungarian supergeniuses, all born in Budapest between 1890 and 1920. These included Manhattan Project founder Leo Szilard, H-bomb creator Edward Teller, Nobel-Prize-winning quantum physicist Eugene Wigner, and legendary polymath John von Neumann, namesake of the List Of Things Named After John Von Neumann.

The coincidences actually pile up beyond this. Von Neumann, Wigner, and possibly Teller all went to the same central Budapest high school at about the same time, leading a friend to joke about the atomic bomb being basically a Hungarian high school science fair project.

Those geniuses weren’t of Martian descent:

Here’s something interesting: every single person I mentioned above is of Jewish descent. Every single one. This isn’t some clever setup where I only selected Jewish-Hungarians in order to spring this on you later. I selected all the interesting Hungarians I could find, then went back and checked, and every one of them was Jewish.

Scott Alexander presents a pretty reasonable explanation of the Martian phenomenon:

For the reasons suggested by Cochran, Hardy, and Harpending, Ashkenazi Jews had the potential for very high intelligence. They were mostly too poor and discriminated against to take advantage of it. Around 1880, this changed in a few advanced Central European economies like Germany, Austria, and Hungary. Austria didn’t have many Jews. Germany had a lot of Jews, but it was a big country, so nobody really noticed. Hungary had a lot of Jews, all concentrated in Budapest, and so it was really surprising when all of a sudden everyone from Budapest started winning Nobel Prizes around the same time. This continued until World War II, and then all anyone remembered was “Hey, wasn’t it funny that so many smart people were born in Budapest between 1880 and 1920?”

Thermodynamics would be the village witch

Tuesday, May 23rd, 2017

If I had to make up some ludicrous technobabble, it would be hard to beat quantum thermodynamics:

“If physical theories were people, thermodynamics would be the village witch,” the physicist Lídia del Rio and co-authors wrote last year in Journal of Physics A. “The other theories find her somewhat odd, somehow different in nature from the rest, yet everyone comes to her for advice, and no one dares to contradict her.”

Unlike, say, the Standard Model of particle physics, which tries to get at what exists, the laws of thermodynamics only say what can and can’t be done. But one of the strangest things about the theory is that these rules seem subjective. A gas made of particles that in aggregate all appear to be the same temperature — and therefore unable to do work — might, upon closer inspection, have microscopic temperature differences that could be exploited after all. As the 19th-century physicist James Clerk Maxwell put it, “The idea of dissipation of energy depends on the extent of our knowledge.”

In recent years, a revolutionary understanding of thermodynamics has emerged that explains this subjectivity using quantum information theory — “a toddler among physical theories,” as del Rio and co-authors put it, that describes the spread of information through quantum systems.

[...]

Over the past decade, Popescu and his Bristol colleagues, along with other groups, have argued that energy spreads to cold objects from hot ones because of the way information spreads between particles. According to quantum theory, the physical properties of particles are probabilistic; instead of being representable as 1 or 0, they can have some probability of being 1 and some probability of being 0 at the same time. When particles interact, they can also become entangled, joining together the probability distributions that describe both of their states. A central pillar of quantum theory is that the information — the probabilistic 1s and 0s representing particles’ states — is never lost. (The present state of the universe preserves all information about the past.)

Over time, however, as particles interact and become increasingly entangled, information about their individual states spreads and becomes shuffled and shared among more and more particles. Popescu and his colleagues believe that the arrow of increasing quantum entanglement underlies the expected rise in entropy — the thermodynamic arrow of time. A cup of coffee cools to room temperature, they explain, because as coffee molecules collide with air molecules, the information that encodes their energy leaks out and is shared by the surrounding air.

Understanding entropy as a subjective measure allows the universe as a whole to evolve without ever losing information. Even as parts of the universe, such as coffee, engines and people, experience rising entropy as their quantum information dilutes, the global entropy of the universe stays forever zero.

Renato Renner, a professor at ETH Zurich in Switzerland, described this as a radical shift in perspective. Fifteen years ago, “we thought of entropy as a property of a thermodynamic system,” he said. “Now in information theory, we wouldn’t say entropy is a property of a system, but a property of an observer who describes a system.”

The Tibetans do things differently

Saturday, May 20th, 2017

Tibetans have evolved and maintained genetic adaptations that suit them to life above 15,000 feet:

Huff and co-authors published a study in April in PLOS Genetics analyzing for the first time whole-genome sequences for 27 Tibetan individuals. The research identified three new genes that help with mountain living, in addition to confirming two that were previously known. These gene variants give Tibetans the ability to metabolize oxygen more efficiently and protect against Vitamin D deficiency.

[...]

One of the genes that helps Tibetans adapt to high altitude is known as EPAS1. The Tibetan variant of this gene does a surprising thing — it actually lowers the hemoglobin count in your blood at high altitudes. Hemoglobins are a protein in red blood cells that transport oxygen to your body. It’s surprising that Tibetans would have a lower hemoglobin count at high altitudes; normally our bodies respond to lower oxygen pressures by increasing hemoglobins in our blood, allowing for more O2 to reach the muscles. It’s even more surprising because other population groups that have adapted to high altitude environments, including the South American Andes and Africa’s Ethiopian Highlands, have done so in part by raising hemoglobin count.

The Tibetans, however, do things differently. Rather than upping hemoglobin count, their bodies have several adaptations that allow them to use oxygen more efficiently, so they need less of it. This allows them to keep hemoglobin counts relatively low at high altitude, which helps to avoid some of the potential downsides of a high hemoglobin count. Hemoglobins thicken the blood, and the thicker your blood the more likely it is to clot, which increases the risk of heart disease and stroke.

A parable of the lessons that can emerge from unfettered science

Tuesday, May 16th, 2017

I was immediately fascinated by the Siberian farm fox experiment and the surprisingly broad domestication phenotype, which notably includes pigmentation.

Marlene Zuk reviews Dugatkin and Trut’s How to Tame a Fox (and Build a Dog) for The New York Times, and ends on this note:

The book, however, is not only about dogs, or foxes, or even science under siege from political interests. It is an exploration of how genes, evolution and then environment shape behavior, and in a way that puts paid simplistic arguments about nature versus nurture. It may serve — particularly now — as a parable of the lessons that can emerge from unfettered science, if we have the courage to let it unfold.

Marlene Zuk wrote Paleofantasy: What Evolution Really Tells Us About Sex, Diet and How We Live.

There is a difficulty with giving The Bell Curve a chance

Friday, May 12th, 2017

Charles Murray explains his controversial book The Bell Curve:

In April, I recorded an interview of almost two and a half hours with Sam Harris for his Waking Up podcast, which, I learned only after I had done it, regularly attracts a few million listeners. We spent more than half of the interview discussing what is actually in “The Bell Curve” as opposed to what people think is in it. Both of us expected our Twitter feeds to light up with nasty reactions after the interview was posted. But the opposite happened. The nasty reactions were far outnumbered by people who said they had always assumed that “The Bell Curve” was the hateful pseudoscientific mess that the critics had claimed, but had now decided they wanted to give the book a chance. It has been a heartening experience.

However, there is a difficulty with giving “The Bell Curve” a chance. The paperback edition has 26 pages of front material, 552 pages of main text, a 23-page response to the critics, 111 pages of appendixes, another 111 pages of endnotes, and a 58-page bibliography. It’s a lot to get through. But there’s a shorter way to get a good idea of what’s in the book: Dick Herrnstein and I began each chapter with a summary that was usually about a page long. With the publisher’s permission, I have stitched all of those summaries together, along with selections from the Introduction and the openings to each of the four parts of the book. If these tidbits arouse enough interest that you buy the book, I will be delighted. But at this point in my life, my main objective is that a labor of love, written with a friend who I still miss twenty-three years after his death, be seen for what it is.

Chronotherapy

Tuesday, May 9th, 2017

Keeping the body’s cells synced up matters for health:

In 2007, based on epidemiological studies, the International Agency for Research on Cancer declared shift work, which causes circadian disruption, a carcinogen. Other studies have elucidated a link between immune cell activity and glucocorticoids—which are secreted in circadian patterns and regulate peripheral clocks—as well as a role for chronic stress in perturbing daily cycles in gene expression, which can alter immune, endocrine, and other functions.

[...]

Genes involved in cell division were among the earliest identified as being rhythmically expressed in both rodent models and human cells. In 1987, researchers studying ovarian cancers found that tumor cells synthesized DNA on a daily rhythm that typically peaked in the late morning hours, nearly 12 hours out of sync with nontumor cells. This led the team to suggest that timing chemotherapy doses that target cells actively replicating their DNA might improve the drugs’ effectiveness while reducing healthy-cell death.

Sure enough, over the past 30 years, experimental models and clinical trials have found that timing chemo regimens can significantly affect their toxicity and effectiveness. In animal studies of nearly 30 chemo drugs, tailoring dosing time to the medication’s mode of action has been found to decrease toxic side effects and increase effectiveness. In one study, rats that received the chemotherapy drug cisplatin at the time of day when their urinary output was highest (a correlate of other timed cycles in kidney metabolism) had fewer nephrotoxic effects, as measured in kidney function tests, than animals that received the doses at the time of minimum urinary output. In another study, oxaliplatin chemotherapy caused fewer intestinal lesions and less bone marrow suppression in mice when given at night, possibly because DNA synthesis in murine bone marrow is highest during the day.

[...]

Clinical trials in 1985 found that antihistamines were most effective when taken at night or early in the morning. Subsequent studies established that inhaling corticosteroids at bedtime, or using delayed-release prednisone formulations that allocated the medication to the body pre-dawn, were most effective at combating allergy symptoms. Cardiovascular events were also recognized early on to cycle throughout the day, as doctors noticed that most patients admitted for heart attacks tended to experience their symptoms between 6:00 a.m. and noon.

Ancient vulture stone carvings confirm comet strike

Saturday, May 6th, 2017

Scientists have speculated for decades that a comet could be behind the sudden fall in temperature during a period known as the Younger Dryas:

But recently the theory appeared to have been debunked by new dating of meteor craters in North America where the comet is thought to have struck.

However, when engineers studied animal carvings made on a pillar – known as the vulture stone – at Gobekli Tepe they discovered that the creatures were actually astronomical symbols which represented constellations and the comet.

The idea had been originally put forward by author Graham Hancock in his book Magicians of the Gods.

Using a computer programme to show where the constellations would have appeared above Turkey thousands of years ago, they were able to pinpoint the comet strike to 10,950BC, the exact time the Younger Dryas begins according to ice core data from Greenland.

Position of the sun and stars on the summer solstice of 10,950BC

The Younger Dryas is viewed as a crucial period for humanity, as it roughly coincides with the emergence of agriculture and the first Neolithic civilisations.

Before the strike, vast areas of wild wheat and barley had allowed nomadic hunters in the Middle East to establish permanent base camps. But the difficult climate conditions following the impact forced communities to come together and work out new ways of maintaining the crops, through watering and selective breeding. Thus farming began, allowing the rise of the first towns.

Edinburgh researchers said the carvings appear to have remained important to the people of Gobekli Tepe for millennia, suggesting that the event and cold climate that followed likely had a very serious impact.

Graham Hancock appeared on Joe Rogan Experience #872 and #725.