You will be ridiculed as an extremist or an alarmist

Thursday, March 12th, 2020

We don’t yet know the full ramifications of the novel coronavirus:

But three crucial facts have become clear in the first months of this extraordinary global event. And what they add up to is not an invocation to stay calm, as so many politicians around the globe are incessantly suggesting; it is, on the contrary, the case for changing our behavior in radical ways—right now.

The first fact is that, at least in the initial stages, documented cases of COVID-19 seem to increase in exponential fashion. On the 23rd of January, China’s Hubei province, which contains the city of Wuhan, had 444 confirmed COVID-19 cases. A week later, by the 30th of January, it had 4,903 cases. Another week later, by the 6th of February, it had 22,112.

The same story is now playing out in other countries around the world. Italy had 62 identified cases of COVID-19 on the 22nd of February. It had 888 cases by the 29th of February, and 4,636 by the 6th of March.

Because the United States has been extremely sluggish in testing patients for the coronavirus, the official tally of 604 likely represents a fraction of the real caseload. But even if we take this number at face value, it suggests that we should prepare to have up to 10 times as many cases a week from today, and up to 100 times as many cases two weeks from today.

The second fact is that this disease is deadlier than the flu, to which the honestly ill-informed and the wantonly irresponsible insist on comparing it. Early guesstimates, made before data were widely available, suggested that the fatality rate for the coronavirus might wind up being about 1 percent. If that guess proves true, the coronavirus is 10 times as deadly as the flu.

But there is reason to fear that the fatality rate could be much higher. According to the World Health Organization, the current case fatality rate—a common measure of what portion of confirmed patients die from a particular disease—stands at 3.4 percent. This figure could be an overstatement, because mild cases of the disease are less likely to be diagnosed. Or it could be an understatement, because many patients have already been diagnosed with the virus but have not yet recovered (and may still die).


Meanwhile, the news from Italy, another country with a highly developed medical system, has so far been shockingly bad. In the affluent region of Lombardy, for example, there have been 7,375 confirmed cases of the virus as of Sunday. Of these patients, 622 had recovered, 366 had died, and the majority were still sick. Even under the highly implausible assumption that all of the still-sick make a full recovery, this would suggest a case fatality rate of 5 percent—significantly higher, not lower, than in China.

The third fact is that so far only one measure has been effective against the coronavirus: extreme social distancing.


As the [1918 flu] was spreading, Wilmer Krusen, Philadelphia’s health commissioner, allowed a huge parade to take place on September 28; some 200,000 people marched. In the following days and weeks, the bodies piled up in the city’s morgues. By the end of the season, 12,000 residents had died.

In St. Louis, a public-health commissioner named Max Starkloff decided to shut the city down. Ignoring the objections of influential businessmen, he closed the city’s schools, bars, cinemas, and sporting events. Thanks to his bold and unpopular actions, the per capita fatality rate in St. Louis was half that of Philadelphia. (In total, roughly 1,700 people died from influenza in St Louis.)


For a few days, while none of your peers are taking the same steps, moving classes online or canceling campaign events will seem profoundly odd. People are going to get angry. You will be ridiculed as an extremist or an alarmist. But it is still the right thing to do.

Alleviate uncertainty

Thursday, March 12th, 2020

In The Catalyst Jonah Berger explains how to change anyone’s mindreduce reactance, ease endowment, shrink distance, and alleviate uncertainty:

Change usually involves some level of risk. Will a new product be better than the old one? Will a new initiative really save money? Research published in the Quarterly Journal of Economics by three University of Chicago researchers in 2006 found that there is an “uncertainty tax.” People in the study were willing to pay $26 for a $50 gift certificate, but when they were asked how much they’d pay for a lottery ticket that would win them either that same $50 gift card or a $100 one, they were only willing to pay $16, a 40% drop. The uncertainty made them undervalue something that was objectively worth more.

To ease uncertainty, lower the barrier to trial. Don’t just tell people that something is better; allow them to experience it themselves. In the mid-2000s, people didn’t understand cloud storage and worried that it would be difficult to use or that they would lose their work. So Dropbox became part of a vanguard of app firms giving away a version of their service for free. The appetizer helped people to resolve their uncertainty and encouraged them to pay to upgrade to a better version. It helped Dropbox to build a billion-dollar business.

Honda Motor Co.’s Acura division took a similar step in 2008. The luxury brand wasn’t as trusted or well-known as its rivals, so Acura partnered with the high-end W Hotel chain to offer guests a free ride anywhere in town in an Acura. Guests might not have known about or liked Acura, but if they needed a ride somewhere, why not get one for free? The rides removed uncertainty and, according to the company, resulted in tens of thousands of new Acura buyers.

Uncertainty can also be reduced by making things reversible. A few years ago, my girlfriend and I were considering getting a dog. A local shelter had an adorable pit mix puppy, but we weren’t sure we were ready. Would we be home enough? Could we give her enough exercise? There were too many unanswered questions. We started to leave, but then a nice volunteer interjected: “In case it helps, we have a two-week trial period.” Today that girlfriend is my wife, and our dog Zoë is an integral part of our family. The trial didn’t reduce the upfront costs of taking Zoë home—food, shots, a crate, etc.—but it did remove the uncertainty.

We should have worried about things other than climate change

Wednesday, March 11th, 2020

The Covid-19 coronavirus is indeed a wolf, Matt Ridley (The Rational Optimist) argues:

In Aesop’s fable about the boy who cried “Wolf!”, the point of the tale is that eventually there was a wolf, but the boy was not believed because he had given too many false alarms. In my view, the Covid-19 coronavirus is indeed a wolf, or at least has the potential to be one. Many people, including President Trump, think we are over-reacting, because so many past scares have been exaggerated. I think that’s wrong.

Coming from you, a friend said to me the other day, that’s scary. I am known as an obsessive and serial debunker of false alarms. I have been at it for almost 40 years ever since I realised as a science journalist in the 1980s that acid rain was being wildly overblown as a threat to forests (I was right). This scepticism has served me well. I did not believe that mad cow disease would kill hundreds of thousands of people, as some “experts” were claiming in the mid 1990s. In the end just 177 died. Likewise, I refused to panic over bird flu, swine flu, SARS or ebola.

I set out to debunk exaggerated claims about the population explosion, peak oil and peak gas, nuclear winter, the ozone hole, pesticides, species extinction rates, genetically modified crops, sperm counts, ocean acidification and the millennium bug. In every case this made me unpopular and unfashionable, but close to the truth. I said climate change would happen more slowly and with less impact on storms, floods, droughts, sea ice and sea level than even some experts were claiming in the 1990s, let alone the extreme environmentalists, and it has.

It is very easy, in other words, to bet on the tendency of journalists and their readers to engage in a competitive auction of unjustified alarm. “The whole aim of practical politics,” said H.L. Mencken, “is to keep the populace alarmed (and hence clamorous to be led to safety) by an endless series of hobgoblins, most of them imaginary.” And no, the fact that the millennium bug was a damp squib was not because we were well prepared; some countries and industries did nothing and were still fine.

So why don’t I think this hobgoblin is imaginary? First, because lethal plagues have a long track record. From the plague of Justinian to the Black Death to the Spanish flu of 1918 to the HIV epidemic, new diseases have proved they can burn through the human population with frightening efficiency. It’s true we have got better at eradicating infectious diseases through vaccinations, pills and public health, but most viruses are still very hard to cure and some are very easy to catch.

The second reason is that new diseases are often more dangerous than existing ones and this one has jumped from bats, possibly via pangolins. In the past respiratory viruses have generally proved to be low in virulence once they become highly contagious: hence the large number of rhinovirus, adenovirus and coronavirus strains that we call collectively, “the common cold”. Even flu has been relatively less lethal since the special wartime conditions of 1918. But when they first infect our species, viruses can encounter a vulnerable immune system and run riot.

The third reason for alarm in this case is the speed with which Covid-19 has crossed regional and international boundaries. It does seem to have acquired an unusual skill at getting passed on from one person to another, usually not making them so sick that they stay away from meeting other people, which is what prevents ebola causing pandemics, but yet being capable of killing about 1% of people it infects. This is the frightening combination of traits that we have feared might one day arise.

Then there is the effect of globalisation, and the huge growth in international travel. I wrote in my notes in 1996, when reviewing a book on new viruses, “If we persist in creating conditions in which viruses can be easily transmitted and amplified, then we will persist in experiencing waves of new viral epidemics. The problem lies in the ecology of our society, not destruction of the environment.” Human beings are just too tempting an ecosystem for an ambitious virus.

But we have indeed cried wolf over so many issues, that it has contributed to us being underprepared. We should have seen that globalisation would cause such a risk to grow ever larger and taken action to prevent a new virus appearing. We should have worried about things other than climate change.

Shrink distance

Wednesday, March 11th, 2020

Jonah Berger explains how to change anyone’s mind in his new book The Catalystreduce reactance, ease endowment, and shrink distance:

When new information comes in, people tend to compare it to their existing views to see if it is a close enough match to consider. Psychological experiments going back 50 years have found a “zone of acceptance,” an area close enough to people’s existing beliefs that they’ll consider new information. Incoming content that is too far away from their current perspective falls into a region of rejection and gets discounted.

Doctors deal with this issue when trying to get patients to change to healthier behavior. Sure, an overweight person should walk a mile every day, but for someone who hasn’t worked out in months, that’s a big ask. One solution is to start by asking for less or breaking the change down into chunks.

A doctor I spoke with a few years ago was dealing with an obese truck driver who drank three liters of Mountain Dew a day. She knew that telling him to quit cold turkey would fail, so she asked him to try just two liters a day. He grumbled but made the switch. Then, on the next visit, she asked him to cut it down to one liter a day, and only after that succeeded did she suggest cutting the soda out entirely. The trucker still drinks a can of Mountain Dew now and then, but he’s lost more than 25 pounds.

Product designers talk about such gradual shifts in behavior as stepping stones—a way to make a big shift feel less daunting. Uber’s initial model didn’t depend on persuading people to take a ride in a random stranger’s car. That’s exactly what Mom told you not to do. The company started instead by making high-end black-car service more accessible. Only after that gained acceptance did they move down-market to UberX, a cheaper nonluxury option. If Uber had asked people to make such a big change from the beginning, they probably would have failed. It was too far from what people were used to.

Ease endowment

Tuesday, March 10th, 2020

Jonah Berger explains how to change anyone’s mind in his new book The Catalyst, starting with the advice to reduce reactance and then moving on to his second piece of advice, ease endowment:

Research on everything from investment choices to political incumbency demonstrates that people are over-attached to the status quo, what social scientists call the “endowment effect.” We tend to stick with things we know and have used for a long time. Most of us eat the same food we’ve always eaten, buy the same brands we’ve always bought and donate to the same causes we’ve always supported.

Part of the challenge is that the status quo usually isn’t that bad, or else people would have made a change. An analogy can be made to injuries. Which do you think causes more pain: breaking a finger or spraining a finger? The answer might surprise you. It turns out that milder injuries may inflict greater pain overall, because unlike serious injuries, people are less likely to take active steps, such as surgery, to speed recovery. Milder injuries thus don’t get addressed and become nagging injuries that never quite go away.

Change agents combat this phenomenon by bringing the costs of inaction to the surface, helping people to realize that sticking with the status quo isn’t as cost-free as it seems. A financial adviser I know tried everything to convince one middle-aged client that keeping large amounts of money in a low-interest savings account instead of investing it more ambitiously for retirement wouldn’t benefit him in the long term. He liked things as they were and refused to see the upside of change. Finally, she started giving him regular updates on how much he was losing monthly compared with inflation and higher-return investments. That worked.

Similarly, IT consultants often resort to encouraging employees to upgrade to new machines by saying that they will no longer support the old ones, leaving employees to fix their own problems. The technique doesn’t force people to switch, but makes it easier for them to see the cost of doing nothing.

A sizable fraction consistently took home products that bombed

Monday, March 9th, 2020

When Steve Sailer was in the marketing research business, his wife suggested that he start own product testing firm, because it would have the competitive advantage of needing just one single tester:

P&G and Frito-Lay could hire me to take home a case of their planned product. If I really liked their innovation, then they would immediately bury all existing samples in a landfill, burn the recipes, and fire the executives responsible.

It turns out he’s just one of many such harbingers of failure:

What do Crystal Pepsi, Watermelon Oreos, Frito-Lay Lemonade, Coors Rocky Mountain Sparkling Water, Colgate Kitchen Entrees and Cheetos Lip Balm all have in common?

The obvious answer is they are all failed products. What is less obvious is that they may also share a fan base — a quirky subgroup of consumers who are systemically drawn to flops and whose reliably contrarian tastes can be used to forecast bad bets in retail sales, real estate and even politics. These people are known as “harbingers of failure.”

The study of harbingers emerged from a 2015 analysis of purchasing patterns at a national convenience store chain. (In exchange for the data, the researchers agreed not to reveal the identity of the chain.) Drawing on six years’ worth of data from the chain’s loyalty card program, a team of marketing professors led by Eric Anderson of Northwestern University classified customers according to their affinity for buying new products that were later pulled from the shelves because of weak demand. Of the roughly 130,000 customers whose purchases were logged, a sizable fraction (about 25 percent) consistently took home products that bombed.

Reduce reactance

Monday, March 9th, 2020

Jonah Berger explains how to change anyone’s mind, the subject of his new book The Catalyst, starting with the advice to reduce reactance:

People like to feel like they’re in control — in the drivers’ seat. When we try to get them to do something, they feel disempowered. Rather than feeling like they made the choice, they feel like we made it for them. So they say no or do something else, even when they might have originally been happy to go along. Psychologists call this negative response “reactance.”

Decades of consumer behavior research shows that people have an innate anti-persuasion radar. They’re constantly scanning the environment for attempts to influence them, and when they detect one, they deploy a set of countermeasures.

To avoid getting shot down, allow for agency. Guide the path but make sure people feel like they’re still in control. Smart consultants do this when presenting work to clients. If you share just one solution, the clients spend the meeting trying to poke holes in it. To shift this mind-set, good presenters often share multiple options. That way, rather than focusing on flaws, the clients focus on which option they prefer, which makes them much more likely to support moving forward.

Another way to reduce reactance is to highlight a gap between someone’s thoughts and actions, or between what they would recommend to others and what they themselves are doing. A clever pharmaceutical executive in one of my courses told me about a colleague who was wedded to a failing project. She asked him what he would recommend if someone at a different company was considering doing something similar. Given all the information we have now, he acknowledged, it wouldn’t make sense. Then why are we still doing it? she asked. The colleague shuttered the project a month later.

Highlighting such dissonance encourages people to try to resolve it. In the 1990s, researchers at the University of California campuses at Berkeley and Santa Cruz used this idea to get students to save water during a shortage. They asked some students to encourage their peers to take shorter showers, while completing a survey on what water-saving steps they themselves were taking. Then they timed the student volunteers’ showers. Exposing the gap between students’ attitudes and actions reduced their water use by more than 25%.

When a difference really is environmental in origin, it’s easy to prove it

Sunday, March 8th, 2020

Human Diversity by Charles MurrayCharles Murray presents (in Human Diversity) Murray’s Conjecture:

When a difference really is environmental in origin, it’s easy to prove it; when it’s hard to prove an environmental cause, it’s because the role of the environment is minor.

Trekkers with the biggest lungs, the biggest spleens, and the biggest reduction in heart rate during a breath-hold were the least likely to develop symptoms of acute mountain sickness

Sunday, March 8th, 2020

Ever since reading James Nestor’s 2014 book Deep, Alex Hutchinson has been fascinated by the scarcely believable feats of freedivers:

Plunging 335 feet below the surface of the ocean and making it back on a single breath, or simply holding your breath for 11 minutes and 35 seconds, clearly requires a very special set of skills and traits.

But until a recent conference talk, I’d never considered whether those same characteristics might be useful in other settings where oxygen is scarce — such as the thin air of high-altitude trekking and mountaineering.


Schagatay’s initial research interest was in what she calls “professional” freedivers, as opposed to recreational or competitive freedivers.


These diving populations, Schagatay and others have found, share three distinctive characteristics with successful competitive freedivers, who take part in contests around the world sanctioned by AIDA, the international freediving authority:

Big lungs: In one study of 14 world championship freedivers, vital capacity — the maximal amount of air you can expel from your lungs — was correlated with their competition scores. The three best divers in the group had an average vital capacity of 7.9 liters, while the three worst averaged just 6.7 liters. And it’s not just genetic: Schagatay found that an 11-week program of stretching increased lung volume by nearly half a liter.

Lots of red blood cells: Divers do tend to have higher levels of hemoglobin, the component of red blood cells that carries oxygen. That’s probably a direct result of their diving. Even if you just do a series of 15 breath holds, you’ll have a surge of natural EPO an hour later, which triggers red blood cell formation.

But there’s a more direct and immediate way of boosting your red blood cell count: squeezing your spleen, which can store about 300 milliliters of concentrated red blood cells. Seals, who are among the animal kingdom’s most impressive divers, actually store about half their red blood cells in their spleens, so they don’t waste energy pumping all that extra blood around when it’s not needed. When you hold your breath (or even just do a hard workout), your spleen contracts and sends extra oxygen-rich blood into circulation. Not surprisingly, spleen size is correlated with freediving performance.

A robust “mammalian diving response”: When you hold your breath, your heart rate drops by about 10 percent, on average. Submerge your face in water, and it will drop by about 20 percent. Your peripheral blood vessels will also constrict, shunting precious oxygen to the brain and heart. Together, these oxygen-conserving reflexes are known as the mammalian diving response — and once again, the strength of this response is correlated with competitive diving performance.


In a study published last year, they followed 18 trekkers to Everest Base Camp at 17,500 feet (5,360 meters). Sure enough, the trekkers with the biggest lungs, the biggest spleens, and the biggest reduction in heart rate during a breath-hold were the least likely to develop symptoms of acute mountain sickness.

The size of the spleen isn’t the only thing that matters — its benefits depend on a strong squeezing response to get all the red blood cells out. In a 2014 study of eight Everest summiters, they found that three repeated breath holds prior to the ascent caused spleen volume to squeeze, on average, from 213 milliliters to 184 milliliters. After the ascent, the same three breath holds caused the spleen to squeeze down to 132 milliliters. Prolonged exposure to altitude had strengthened the spleen’s diving response. In fact, there’s also evidence that simply arriving at moderate altitude will cause a sustained mild spleen contraction, as your body struggles to cope with the oxygen-poor air.

Conscientiousness consistently played the most important role

Saturday, March 7th, 2020

Human Diversity by Charles MurrayOf the Big Five traits, conscientiousness consistently played the most important role in academic and professional success, Charles Murray explains (in Human Diversity: The Biology of Gender, Race, and Class), with openness in second place:

Poropat reported effect sizes for them of +1.14 and +0.96 respectively, far larger than those for agreeableness (+0.19), emotional stability (+0.36), or extraversion (+0.23). In addition to its value for academic performance, conscientiousness has also been found to predict job performance, salary, promotion, and occupational prestige. These findings make sense.

Patriot Games was notable for subverting the moral ambiguity of the antagonists

Saturday, March 7th, 2020

I somehow managed to go this whole time without reading a single Tom Clancy novel — or watching a single movie adaptation, except for The Hunt for Red October — and only just now listened to the audiobook version of Patriot Games, which was originally published in 1987.

I didn’t remember the character of Jack Ryan, from The Hunt for Red October, so I was a bit surprised to find that he was not a Bond- or Bourne-like super-spy, but a history professor with a wife and daughter — and I was a bit concerned for his family’s safety, in those first few pages, since their deaths could explain and justify a book full of righteous vengeance, but they merely witness the inciting incident of the novel, where our former-Marine hero tackles one Irish terrorist, takes his pistol, and kills another. That seemed…out of character for a professor — even a young one who was briefly a Marine lieutenant — and there really isn’t any further explanation.

The book is a product of its time, and it features the first foreign terrorist attack on American soil. These foreign terrorists are vengeful Irish extremists, and they side with local Marxist revolutionaries belonging to The Movement, a Black Panther-like group. The novel is conspicuously progressive on issues of race and sex. Our hero’s best buddy is a top-notch black fighter pilot — pardon, naval aviator — and the evil Irish terrorists disrespect their more-competent black partners, before turning on them.

The technology is mid-1980s, too, with the “newer” spy satellites using CCDs, which give real-time intel, rather than film, which has to be used up and then dropped back down and recovered for processing. Our hero is oddly rattled by seeing low-res video of a special operations assault on a terrorist training camp.

The coolest gun in the world in the 1980s is the Uzi, which makes an appearance. The pistols offered to our hero include a Colt .45 automatic, a Browning Hi-Power, and a .22 target pistol. The Beretta M9, which was adopted in 1985, doesn’t appear. The grizzled Marine Sergeant Major, Breckenridge, teaches our hero to shoot one-handed, purely for accuracy, before introducing him to the two-handed Weaver stance and “rapid fire” shooting, one shot per second. This is all rather quaint to a modern practical shooter.

When I looked the book up on Wikipedia, it raised a point about it that never occurred to me:

Patriot Games was notable for subverting the moral ambiguity of the antagonists in espionage novels by John le Carré, Len Deighton, and Robert Ludlum. According to Marc Cerasini’s essay on the novel, “Clancy’s sensible revulsion toward the terrorists is so strident and intense…that it verges on the physical.” He added that “the author’s understandable disgust toward his villains is ‘bourgeois’, for there is not a shred of sympathy for these Irish ‘patriots’.”

Yes, terribly bourgeois.

IQ score is a better predictor of job performance than a résumé, evaluation through a job interview, assessment centers, or work samples

Friday, March 6th, 2020

Human Diversity by Charles MurrayOne of the most common assertions about IQ, Charles Murray reminds us (in Human Diversity: The Biology of Gender, Race, and Class), is that it doesn’t predict performance in the real world of work:

The truth is the opposite. It’s not just that IQ predicts job performance for people with cognitively demanding jobs; IQ predicts job performance to some degree for people across the entire range of jobs. People who are responsible for new hires at a workplace should know that an IQ score is a better predictor of job performance than a résumé, evaluation through a job interview, assessment centers, or work samples.

She took 55 milligrams of what she believed was cocaine

Friday, March 6th, 2020

A woman contracted Lyme disease in her early 20s. It damaged her feet and ankles and left her in significant pain, which she treated with morphine — until, decades later, she tried another pharmaceutical:

In September 2015, she took 55 milligrams of what she believed was cocaine but was actually “pure LSD in powder form.”

The authors defined a normal recreational dose as 100 micrograms — equal to 0.1 milligrams.

The woman blacked out and vomited frequently for the next 12 hours but reported feeling “pleasantly high” for the 12 hours after that — still vomiting, but less often.

According to her roommate, she sat mostly still in a chair, either with her eyes open or rolled back, occasionally speaking random words. Ten hours later she was able to hold a conversation and “seemed coherent.”

Her foot pain was gone the next day and she stopped using morphine for five days. While the pain returned, she was able to control it with a lower dose of morphine and a microdose of LCD every three days. After more than two years, in January 2018, she stopped using both morphine and LSD and reported no withdrawal symptoms, although the case report said she did experience an increase in anxiety, depression and social withdrawal.

The case studies were compiled by Mark Haden, executive director of Canada’s Multidisciplinary Association for Psychedelic Studies and an adjunct professor at the University of British Colombia School of Population and Public Health, and Birgitta Woods, a psychiatrist in Vancouver..

They noted that in CB’s case “ingestion of 550 times the normal recreational dosage of LSD was not fatal and had positive effects on pain levels and subsequent morphine withdrawal.”

The authors note in the study that no lethal doses of LSD have been documented, although they said scientists have estimated that a lethal dose in humans would be 14,000 mcg.

All human behavioral traits are heritable

Thursday, March 5th, 2020

Human Diversity by Charles MurrayBehavior geneticist Eric Turkheimer set out three laws of behavior genetics, Charles Murray reminds us (in Human Diversity: The Biology of Gender, Race, and Class):

First law: All human behavioral traits are heritable.
Second law: The effect of being raised in the same family is smaller than the effect of genes.
Third law: A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families.

Murray adds some related findings:

Whether the topic was a Big Five characteristic such as extraversion or neuroticism or more specific characteristics such as tolerance, sense of well-being, or alienation, twin studies of heritability kept coming up with correlations for MZ twins that were more than twice the correlations for DZ twins, leaving no role for the shared environment.


The literature on shared environment, nonshared environment, and heritability tells us that a family’s SES (income, parental education and occupation) is unimportant in explaining the cognitive abilities and personality traits that parents try hardest to promote.


The bulk of the variance in success in life is unexplained by either nature or nurture. Researchers are lucky if they explain half of the variance in educational attainment with measures of abilities and socioeconomic background. They’re lucky if they can explain even a quarter of the variance in earned income with such measures. The takeaway for thinking about our futures as individuals is that we do not live in a deterministic world ruled by either genes or social background, let alone by race or gender.

Salamanders and other amphibians glow green when bathed in blue light

Thursday, March 5th, 2020

Salamanders and other amphibians glow green when bathed in blue light:

Amphibians fluoresce green to yellow in response to blue (440–460?nm) (Figs. 1 and 2) and ultra-violet excitation light (360–380?nm) (Supplementary Fig. 2), but the biofluorescent light emitted under blue excitation is more intense than when excited by ultra-violet light (Supplementary Fig. 2). Fluorescent green coloration in response to blue excitation light is strikingly widespread across the amphibian radiation (Figs. 1 and 2) and is the focus of this survey. Every amphibian species and life stage we examined, including aquatic larvae, is biofluorescent (Supplementary Table 1). Peak fluorescent emissions coming from these amphibians (Fig. 2) fall within the spectrum of green light (ca. 520–560?nm). The intensities of fluorescent light we recorded were variable among taxa (Figs. 1 and 2) and weakest for those that lacked bright or reflective pigments (i.e., yellows, oranges, whites).

Salamanders and other amphibians are aglow with biofluorescence 1