Did Dogs Become Smarter Through Domestication? An Interview with Dr. Brian Hare

published in Skeptic volume 22 number 4
Original PDF file
   

by Felipe Nogueira

Dr. Brian Hare is an associate professor in the Department of Evolutionary Anthropology at Duke University and in the Center for Cognitive Neuroscience. Hare is a pioneer and a key expert in the field of dog psychology. Together with Vanessa Woods, Brian Hare has written about the revolution in the study of dog cognition in the fascinating book The Genius of Dogs: How Dogs Are Smarter Than You Think. The book, in their own words, is “about how cognitive science has come to understand the genius of dogs through experimental games using nothing much more high-tech than toys, cups, balls, and anything else lying around the garage.”

Hare and other researchers showed many times that dogs are good at understanding humans’ communicative intentions. With the help of a brilliant experiment with foxes begun by Dmitri Belyaev in the 1950s and continuing to the present day, Hare’s research uncovered what allowed dogs to develop this remarkable skill: domestication After 45 generations, Belyaev’s foxes in the experimental group had floppy ears, curled tails, and were much better reading human gestures than the foxes in the control group. The key point is that Belyaev didn’t select for foxes better at reading human gestures; instead he selected for foxes less afraid and friendlier towards humans. As Hare and Woods note in their book: “Domestication, selecting the friendliest foxes for breeding, had caused cognitive evolution.”

In order to understand even more the limitations and flexibility of canine cognition, researchers have created dedicated laboratories, such the Duke Canine Cognition Center, created by Hare. 

Dr. Brian Hare

Nogueira: In your book, you talked about the genius of dogs. But what do you mean by being a genius?

Hare: If you’re talking about high IQ, or who is going to be recruited to work for NASA, that would make a very short book. In my opinion, the big discovery in the cognition revolution is that cognition it’s not a unique dimensional trait. Actually, it’s a whole set of skills that can vary independently and we don’t know how many there are. For instance, one can be great at math, but a terrible communicator. Regarding species, each one evolved to solve a set of problems that helped them survive and reproduce in their particular environment; dogs are no different. My book The Genius of Dogs is all about trying to understand how a species that seems utterly unremarkable can can be so successful. Dogs are successful from an evolutionary perspective because, everywhere there are people, there are dogs. It’s the most successful mammal—aside from humans and maybe cows. That’s what the book explores: do dogs have some type of genius psychologically or cognitively? Yes, they show unusual degree of sophistication and flexibility for solving problems.

Nogueira: Tell us how you started researching dog cognition.

Hare: Michael Tomasello, a developmental psychologist and my research supervisor at the time, was explaining to me how important gesture communication is in human development. He thought it was not only crucial to human evolution but something unique to humans. His theory was that kids developed the ability to use human gestures and to understand communicative intention. Then I told him that my dog could do the same thing. That’s when I learned what science is, because even though it was an important idea for how humans evolved, Tomasello became curious. He said to me: “I will help you to come up with a way to prove me wrong.” That’s incredible! When he discovered that he was wrong about dogs, he was excited, telling us to keep doing more experiments. People think science is about people in lab coats coming up with genius ideas, but in reality it’s a way to falsify ideas.

Nogueira: How was the first experiment with dogs?

Hare: We use a powerful, but very simple technique: we hide food in one of two containers. Then we pointed to where we hide it, trying to help the dog search for it. Great-apes are terrible at this task. They don’t show much cognitive flexibility, since they have to learn the gesture. And every time you use a new gesture, they have to learn again. In contrast, in kids around age 12 months, you can use gestures they’ve never seen before, showing a degree of flexibility that it’s not seen in great apes. With dogs we performed the same series of experiments that had been done with apes and human children. The big surprise was that dogs are more like children.

            This was a controlled experiment: dogs were not using their noses nor reacting to motion. In science, there are two steps. First, you have to demonstrate a phenomenon. If it’s gravitational waves or dogs following gesture, you have to demonstrate the phenomenon. Then, you try to explain it. Often, people are so busy trying to explain something before they even demonstrate it exists. Once we demonstrated that dogs were following a pointing gesture, we wanted to know if they, for example, just smelled the hidden food. We found that wolves, dogs and foxes all preferred to use their eyes. When they can’t get the information they need from their eyes, then they use their nose. In these experiments, we found that dogs prioritize information from their eyes and memory over their nose.

Nogueira: One of the fascinating experiments with dogs you mentioned in the book uses an opaque barrier. Could you elaborate on it?

Hare: This is the work of Juliane Kaminsky, Michael Tomasello, and Josep Call. They have placed a ball behind two barriers, one opaque and one transparent. The dog can see both balls. In the experimental condition, a human, on the opposite side of the barriers, asks the dog to fetch the ball. The amazing thing is that dogs didn’t take the ball from the opaque barrier, which the human can’t see through; they favored the ball from the transparent barrier. In the control condition, where the human and the dog are on the same side, seeing the same thing, the dog choose the balls randomly. This experiment suggests that dogs know what humans can or cannot see.

Experiment conducted by Kaminski et al [2].

Nogueira: What are the possible explanations for why dogs are so good at reading human gestures?

Hare: One level of explanation is that, since dogs have seen these gestures several times, they slowly learned them. You can test this idea by using a gesture they’ve never seen before, for instance, point with your foot. You can also use a crazy gesture, like putting an object on top of the container where the food is located. Human children and dogs follow those gestures, but chimpanzees don’t. So, this hypothesis of slow learning was ruled out. But the hard part is this: how do you know if dogs really have a sophisticated flexible strategy, a theory of mind, which would mean that they’re thinking about the thought of others individuals?. The best evidence about other animals that have a theory of mind comes from great apes and maybe corvids. Regarding dogs, in fact, we don’t have the smoking-gun experiment to rule out alternative explanations. Then, we don’t have overwhelming evidence that dogs really have a theory of mind. For instance, the experiment with the opaque barrier, when the dog knows what people can or cannot see, hasn’t been replicated. Moreover, when you are studying something like a theory of mind, you want multiple experiments where an animal shows the same set of skills. We have that with great apes, but we don’t have with dogs yet.

Nogueira: From where do these remarkable skills of dogs come?

Hare: We tested several hypotheses. The first was that they were related to wolves, which are clever and maybe are also good at reading human gestures. The other was experience: they interacted with us and have slowly learned it. Finally, we considered if it’s something that happened during domestication. The evidence is mostly in favor of domestication: selection for friendliness is what allowed dogs to become more skilled at reading and using humans to solve problems. That was a surprise: why would being selected to be friendly make you smarter?

Nogueira: How has the Belyaev’ fox research helped to answer that question?

Hare: This brilliant experiment was conducted by a group of scientists in Siberia headed by Dmitri Belyaev. They have a control and experimental line of foxes, separated from each other. The control line was bred randomly. In the experimental line, Belyaev selected foxes that were attracted to or enjoyed interacting with people and weren’t fearful. In other words, Belyaev selected friendly foxes and let them breed together. Over many generations, the experimental foxes show a high frequency of traits that Belyaev didn’t select for, such as floppy ears, curly tails, and multi-color coats. The foxes also had physiological changes related to reduction in aggression and increased friendliness. This experiment was important to our research because they have a population that was experimentally domesticated. This was a great opportunity to test the idea that if domestication really is selection against aggression and for friendliness for people. It makes sense: how can you have a domesticated animal if it just wants to attack you or is too scared to come near you? The foxes also led us to questions about psychology: Is this remarkable ability of reading human gestures and to use humans as social tools also a product of selection for friendliness? The answer is yes: the domesticated foxes acted like dogs regarding their ability to read human gestures while the control line did not; they behaved like wolves.

Nogueira: You mention in your book that, “without an experiment, we were slipping from science into the realm of storytelling.” Could you elaborate why we need experiments? 

Hare: We published a paper in Science ruling out the first two hypotheses.¹ The first is that dogs’ remarkable skills of reading human gestures evolved in wolves and were inherited. Second: lots of experience gives dogs these skills. We didn’t find any evidence for these hypotheses, so by default we favored the domestication hypothesis. We didn’t have evidence for it; we only had evidence against the other two hypotheses. If Belyaev had not done his domestication experiment, we would have been stuck at that point. Belyaev’s work established the possibility of testing if domestication made dogs able to read human gestures. We did an experiment with the foxes and we were surprised: even though they were not selected to be smarter or to be better at using human gestures, they were as a result of being selected for friendliness. We had direct evidence that it was domestication that did it.² People might think that we domesticated dogs and made them smarter, but it does not mean it’s true.

Nogueira: If it’s not true, what probably have happened?

 Hare: People tend to think we created dogs as our own image. The best evidence suggests that animals had an advantage if they were friendly to people; they will reproduce more. I was in a restaurant eating outside and there were sparrows stealing food in a few inches of my feet. Those sparrows are eating tons of food, they are fat and healthy. That’s because they’re not afraid of people. I think something like that happened with dogs. In some point of human evolution, humans created a new food resource that if you could be friendly enough and not fearful of human population you were a big-time evolutionary winner. So, a population of wolves chose us; we didn’t choose them. Since hunter-gathers competed with wolves, it does not make sense to bring animal like wolves close to your children. The wolves realized, just like the birds under my table realized, the wonderful resource is scraps around human camps. After a few generations, they would show morphological changes, like those we’ve seen in the foxes, so people could tell the difference between those and the other wolves we competed with. That would be a major selection advantage.

Nogueira: How evolution is related to those changes?

Hare: Selection against aggression and for friendliness toward people creates several changes beyond that in morphology and psychology. Once these new differences are there, selection can act on that too. The point is that these new changes were not created; humans did not think to create dogs with floppy ears, for example. Some individuals had floppy ears because selection against aggression. Then people could breed these individuals to make more floppy ears. In other words, we took the advantage of the variance created by the selection against aggression. Evolution is not any different to gravity. If I drop a ball, I can’t stop it from dropping; it’s unstoppable force. Evolution is also unstoppable. Just because you can’t see, it does not mean it’s not acting all the time. Another example is that there is a white deer that comes to eat in my front yard. Normally, deer coming near humans is a bad idea. If you live in hundred yards from my house, a deer in your front yard would soon be dinner. But where I live in the suburbs everybody think deer are cute and adorable. Where I live, there is higher proportion of deer with different color coats; there are more white and albino deer. Research already shows that deer that are invading urban areas are larger, more social and have more offspring than deer living far away from humans.*

Nogueira: This process of domestication that happened with dogs probably have happened with other animals well, which we called convergence of evolution. What do we find, for example, when we compare chimpanzees and bonobos behavior regarding aggression, attitudes towards strangers and so on?

Hare: Bonobos served as a test-case for the hypothesis that natural selection, and not artificial selection, caused domestication. We called it self-domestication: species, through natural selection interfacing with its environment, end up like a domesticated animal. When we compare chimpanzees and bonobos to wolves and dogs, many changes between wolves and dogs were found between chimpanzees and bonobos. Chimpanzees are like the wolf of the ape family. Weather we’re talking about morphological or behavior characteristics, bonobos are really the dog of the Ape family.

Nogueira: At Skeptic, we advocate for evidence-base thinking. Since you had communicated with the public, what do you think is the best approach to shift people from faith-based thinking to evidence-based thinking, increasing, for example, the acceptance of evolution?

Hare: In US, people think that Christians have a problem with evolution, but the Catholic Church says evolution is consistent with Catholic doctrine. People love to play the “in and out” group card: science is something that other people do. If one is religious and faithful, one can’t believe in science, since science is anti-religion. That’s the typical in-out group response. People use strategies to target science, or evolutionary thinking, as the out group. As someone who studies evolution, the first thing is to notice that humans evolved to see in-out group everywhere. If you say something like “you’re religious and you’re not like me”, it’s over. As a science communicator, I’m going to say that Catholic Church has no problem with my research in order to turn-off the in-group out-group response. The entire intent of my book The Genius of Dogs is to get people who had never read about evolution and cognitive science excited to read about it, because they care about dogs. Darwin intentionally started The Origins of Species with a chapter about domestication, because he knew people were familiar with and were not threaten by it. I think we have to do the same thing.

Nogueira: Thank you for this amazing interview and keep up the fascinating research!

References

1.    Hare B, Tomasello M. 2005. Human-like social skills in dogs? Trends in Cognitive Sciences 9: 439–444. https://www.ncbi.nlm.nih.gov/pubmed/16061417.  

2.    Kaminski J, Bräuer J, Call J, Tomasello M. 2009. Domestic dogs are sensitive to a human’s perspective. Behaviour 146: 979-998 https://doglab.shh.mpg.de/ pdf/Kaminski_et_al_2009a_dogs_sensitive_humans _perspective.pdf.

3.    Hare, B Hare, B., Homo sapiens Evolved via Selection for Prosociality. Annu Rev Psychol. 68:155-186: https://www.ncbi.nlm.nih.gov/pubmed/27732802

4.    Hare B., M. Brown, C. Williamson, and M. Tomasello. 2002. “The domestication of social cognition in dogs.” Science. 298: 1634-6.

5.    Hare B., et al. 2005. “Social cognitive evolution in captive foxes is a correlated by-product of experimental domestication.” Current Biology. 15: 226-30.

Notes
* Here I corrected a minor mistake that was published in the original version at the magazine. I also corrected Figure 2's subtitle: the correct reference number is 2 (Kaminski et al, 2009). 

Reflections on Pandora's Lab

Published in Skeptical Briefs volume 27, number 1, 2017.
by Felipe Nogueira

In my last column, we briefly saw that Dr. Paul Offit’ latest book is Pandora’s Lab. As the subtitles explains is about Seven Stories of Science Gone Wrong. The book theme is simple: even though science has done good in the world, every possible invention might have bad consequences. If we accept new discoveries at face value, or to better put it, without the skepticism that science itself has taught us, we might, even with the opposite intention, doing harm. In some cases, avoidable harms; in other cases even more harm than good.

“Science can be Pandora’s beautiful box”, writes Offit. The seven stories covered in the book exemplify it very well. What connected those stories, besides science going wrong, is that they started in history, but their impact can be felt until today. Thus, as Offit shows in the final chapter, their lesson is still unlearned.

The lesson of vilifying saturated fat as the cause of heart disease still lives with us today. As clear explained in the book, heart disease or atherosclerosis happens when either of the coronaries arteries is blocked, interrupting the blood flow, damaging the heart, which occasionally might result in death.  The hypothesis that diet impacts heart diseases, recollects Offit, started in 1913 when a Russian study found that rabbits fed large quantities of foods rich in cholesterol (milk and egg yolks) developed atherosclerosis. Thus, the study’s author hypothesized that heart disease might be controlled by diet, specifically, by eating less cholesterol.

Another relevant study was done by Ancel Keys, who in 1950 compared people’s diet in several different countries. He found that countries with greater amount of fat in peoples’ diet, such as Finland, had higher incidence of heart disease. As such, he was the first person to use the term “heart-healthy diet”, urging Americans to restrict their fat intake. In 1961, the American Heart Association recommended to not eat more than 300 mg of daily cholesterol. There was only one problem with these recommendations: “scientific data on the relationship between fat consumption and human health remained, at best, ambiguous”, in Offit’s own words.

While data weren’t clear for radical interventions, restricting diet fat became government policy. Another crusader against fat was Senator George McGovern, who founded a nutrition committee responsible for a report wrote by politicians, instead of nutrition scientists or specialists.

In the 1980s, a non-governmental company called Center for Science in the Public Interest (CSPI) target restaurants and other food companies that used saturated fat based oils. This was a response to several studies that found saturated fat as the culprit of heart disease and that unsaturated fats were good for health. That’s what led us to the great margarine mistake. Following the push against saturated fat, the public reduced the amount of butter consumed, replacing it with margarine. Restaurants and food supply also made changes. They started using partially hydrogenated vegetable oils. As Offit put it, “In the 1980s, partially hydrogenated vegetable oils became the single most product for all baking and frying”.

Foods containing animal fats, such as butter and those oils previously used by industry, are rich in saturated fat. In contrast, margarine (at the time) and partially hydrogenated vegetable oils have great quantities of trans unsaturated fat, or trans-fat. In the 1980s and 1990s, studies linked partially hydrogenated vegetable oils with heart disease. Offit is crystal clear:
“The Harvard School of public health later estimated that eliminating trans fats from the American diet would prevent 250,000 heart attacks and related deaths every year!

Unlike studies of total fat, total cholesterol and unsaturated fat – where findings had been contradictory or inconclusive – no researcher has ever published a paper showing that trans fats are anything other than one of the most harmful products ever made.”
By trying to make us healthier, we ended up creating a much bigger problem. We didn’t know if trans-fat were safe or not, but our desperation to remove saturated fat from the diet certainly has led us astray: “in 2006, an article in the New England Journal Of Medicine declared ‘On a per calorie basis, trans fat appear to increase the risk of coronary heart disease more than any other macronutrient.’”

If that mistake was not enough, Offit brilliantly remember our desire to cure or treat mental illness was even more tragic. In attempt to understand the function of brain areas related to memory tasks, two researchers removed the frontal lobes of two chimpanzees. After the procedure, both chimps didn't remember how to get food. So, the researchers believed frontal lobes were responsible for creating and storing recent memories. But something else had happened. It seemed that one of the chimps didn't care for her recent memory limitation, as if she had "joined a happiness cult", in the words of one of researchers. They believed they had invented a treatment for anxiety.

It didn't require much time for someone trying this procedure called lobotomies in humans. In the late 1930s, several countries like performed lobotomies. One responsible for the apparent success of lobotomies was the neurologist Egas Moniz, who published a long monograph describing the procedure results in his 20 patients. Moniz reported improvements in more than half of it, even though adverse events like vomiting, diarrhea, nystagmus, and disturbed orientation of time and space happened. Surprisingly, Moniz was awarded the Sweden's Nobel Prize for his invention. The consequence was nothing to be awarded for: within four decades, 40,000 lobotomies were performed in the world.

The United States also had their lobotomy pusher: Walter Freeman. His "insight" was making a much more fast procedure, using electroshock for anesthesia and an ice pick. In 1950, Freeman wrote a book reporting the results of many of his “ice pick lobotomies”. While patients had several adverse events (as had happened with Moniz's patients), Freeman concluded his invention was successful. But Offit is clear about the patients:

"would lie in their bed like 'wax dummies' and have to be turned constantly by visiting nurses or family members to keep from getting bedsores. All were profoundly inddiferent to their surroundings. They didn't seem to care about anything. Worse, they had lost any sense of decorum". 

Despite serious adverse events (3% died from bleeding and other 3% faced permanent seizures), no medical society or organization stood up against lobotomies. According to Offit, it was the invention and use of psychoactive drugs that lessen the number lobotomies performed.

In a page-turner way, Offit tell us more five lessons of the past. God’s Own Medicine, or the story about the creation and use of opioid pain-killers, appeared in the latest issue of Skeptical Inquirer. We can learn the lesson from those stories to apply them to the present future.

That's what Offit does in the final chapter, for example discussing the problem of overdiagnosis and overtreatment with cancer screening programs. We must recognize as Offit explains that cancer's definition is changing. Not all of the detected cancers are going to kill us. Screening with PSA-test made prostate cancer the most commonly diagnosed non-skin cancer in the United States. But the risk of death due to prostate cancer remains unchanged in the last ten years. Critically, in men with 60 years or more that died from other causes, autopsies found prostate cancer in half of them. A similar situation is seemed in thyroid cancers, which are found in autopsies in one-third of people that had died from something else. The screening for breast cancer, another that in Brazil has a dedicated month to its promotion and awareness, it’s just a bit better because it saves some lives, but not many lives we’d think or like. Only 8 women of 122 benefit from it. The problem is what happened with the others: mastectomy, radiation therapy, chemotherapy with no evidence of benefit. Alarmingly, it’s estimated that 1.3 million women had been diagnosed with a breast cancer that would never killed them.

One clear lesson is to be cautions of anecdotes. Those pushers for lobotomies believed their procedure was saving lives. That’s why we need careful and controlled studies to evaluate the efficacy and safety of interventions.  So, Pandora’s Lab main lesson is to apply the skepticism even to science’s new inventions. Actually, accepting new inventions coming from science or not with face value is, in fact, not scientifically. The book beautiful reminds us that one of the big lessons of science is the skepticism and the importance in the promotion of science and critical thinking we do in CSI. The conclusion:

we need to approach all scientific advances cautiously and with eyes wide open – and to make sure that we learn from our mistakes and aren’t paralyzed by them.  

To Be More Skeptical about Anti-Vaccination and Vitamins Supplements.

An Interview with Paul Offit

by Felipe Nogueira

published in Skeptical Briefs volume 26, number 4, winter 2016/2017

Dr. Paul Offit is a pediatrician, the Chief of the Division of Infectious Diseases of the Children's Hospital of Philadelphia, and was the co-inventor of the rotavirus vaccine. He wrote several books about the importance of vaccines, clarifying the risks, which is often misunderstood. For example, the anti-vaccination movement insists that MMR vaccine causes autism. However, that relationship was already analyzed scientifically and we know it's wrong. In his book Do You Believe in Magic?, Offit makes a critical analysis of alternative medicine and the use of large dose of vitamins supplements. It’s important to raise the awareness about the vitamins supplements: it’s unregulated industry that claims vitamins supplements prevent disease. However, several studies [1-3] say most supplements do not prevent disease and some, such as vitamin E and beta-carotene [4], can increase the risk of cancer and mortality. Paul Offit’s website is www.paul-offit.com

Nogueira: Can you pinpoint when the anti-vaccination movement started? 

Offit: I think it started with the first vaccine. The smallpox vaccine was developed by Edward Jennen in 1700s. There was violent opposition to the vaccine in the early 1800s because that vaccine was mandated. I think the professional anti-vaccine people, like National Vaccine Information Center, Moms Against Mercury, Safeminds, and Generation Rescue, will say they would stop their anti-vaccine efforts if you simply make vaccines optional.

Nogueira: What exactly is the risk of Guillain-Barré syndrome [5] (GBS) after influenza vaccine? 

Offit: We can say with confidence that the 1976 swine flu vaccine had a risk of GBS in 1 per 100.000 who were given the vaccine. It’s not clear that since then any vaccine causes GBS. CDC and other groups that tried to categorize this always say that we cannot say is more common than 1 per million. The people are left with this vague notion that vaccine might cause GBS, but since the 1976 swine flu vaccine there is no clear evidence that it has.

Nogueira: If a vaccine causes a symptom, usually the disease the vaccine tries to prevent causes the same symptom. Can you clarify?

Offit: The best example is thrombocytopenia, which is low platelets level. There are a couple of studies and they all have been consistent and reproducible: the measles vaccine causes thrombocytopenia in 1 per 25-30 recipients. A measles virus also causes thrombocytopenia, but it is far more common. Another example: from 8 to 12 days after receiving chicken-pox vaccine, one can get a mild chicken-pox rash with 5 blisters, but sometimes can be 30 blisters. But chicken-pox natural infection can cause 300 to 500 blisters.

Nogueira: Knowing that MMR vaccine does not cause autism, how dangerous is to widespread information not corroborated by science?

Offit: I think once you scare people, it's hard to unscare them; once you open the Pandora’s box, it's hard to close it. The question was raised by Andrew Wakefield in 1998 with his publication in The Lancet, which wasn't a study. It was a simple case series: 8 children who had received the vaccine and developed symptoms of autism within 1 month. There are now 12 studies, looking to large number of people who did and didn't get the vaccine to answer the question "are you at a greater risk of having autism if you receive MMR vaccine?" The answer has been very reproducible: no. I think people are far more compelled by anecdote than they are by statistics. If Jenny McCarthy gets on Oprah and says "I watch my son get this vaccine, I watch his soul leave his eyes" and she cries, that's very compelling. A scientist on the show would say "fair question: could the vaccine cause autism?  Is this a causal effect relationship? Is this just a temporal effect or it is a plausible effect?" This is a scientific question and it has been answered in a scientific venue. But how do you trump the anecdote with science? The media became critical and they're not great at it.

Nogueira: Moving into vitamins supplements, when this idea begun? 

Offit: We need vitamins, no doubt it. If we don’t get enough of it from diet, we suffer diseases like pellagra, scurvy and rickets.[6] But we crossed the line from certain amount is good to therefore more would be better. That’s not true. Once you’re above the protective levels, you don’t need to be above of it. And I think the “big push” for supplements came in 1970s with Linus Pauling, who won Nobel Prizes in Chemistry and Peace. He was a strong voice and used to push vitamins supplements. Some of the earlier supplements were called Linus Pauling vitamins.

Nogueira: What about the risks of taking vitamin E? 

Offit: What amazes me about the vitamin E story is that there is a preparation of vitamin E that said "natural E 1000". If you look on the back label, it said that it had 3333% of the recommend daily allowance. You would have to eat about 1650 almonds, which are good source of vitamin E, to get the same amount from one gel capsule. That's not a natural thing to do. And if you take large doses of vitamin A, E or beta-carotene for prolonged period of time, you increase your risk of cancer and heart disease and potentially shorten your life. Those data are clear; there are twenty studies now that show that.

      

Nogueira: There is an article discussing that laboratory cut-off values for vitamin D are  not evidence-based. What can you say about it?

Offit: You’re right. Suddenly in the United States everybody has become vitamin D deficient. Certainly, it’s not because there’s been an outbreak of rickets; that hasn’t happened. It’s because of serum tests. I think what is considered normal values are not validated. Because of incorrect levels, all my friends tell me their doctors prescribed vitamin D for them. I like to think this is fad and will pass in a few years, because we’re doing no good and potentially some harm.    

Nogueira: Do you think there is enough evidence for vitamin D supplementation to prevent falls or fractures?

Offit: The U.S. Preventive Services Task Force (USPSTF) had at one point supported the use of vitamin D specially to prevent osteoporosis. The bone gets thinning in older people, so when they fall, they’re more likely to have fractures. Postmenopausal women are more likely to have these fractures. Then, vitamin D was recommended, since it helps to increase the uptake of calcium in the intestinal tract. However, with more data available, USPSTF does not recommend it anymore, since there is no clear evidence that postmenopausal woman or older people benefit from the intake of vitamin D or calcium.     

Nogueira: Where do you think came from this notion that vitamin supplements are natural? 

Offit: I give credit to the industry, which has been able to sell itself as natural. The nutraceutical and dietary supplements industry sell their supplements “as all natural, it can’t hurt you and it’s being made by old hippies”. This is not true. Pfizer and Hoffman-LaRoche are major players in dietary supplement game. It’s an unregulated industry with no obligation to support its claims. And, in United States, they have enough political influence to keep the FDA away from regulating them. Also, it’s very hard to be vitamin deficient; everything is supplemented. For example, it’s hard to suffer from folic acid deficiency in US, because grains, cereals, and pastas are supplemented with folic acid.

Nogueira: Your latest book is Bad Faith. What’s all about it?

Offit: It’s about how, in the United States, people have been able to use their faith to medically neglect their children. I think people should not be able to use the law to medically neglect their child. For example, 47 states have religious exemptions for vaccines. So, the book’s message is “we should not allow people in this country to use religion to put children in harm’s way.”

Nogueira: Have you planned a next book?

Offit: I have a new book coming out in April. The title is Pandora’s lab. Seven Stories of Science Gone Wrong. It’s about scientific discoveries that change the world for the worst.

Nogueira: Thanks for this thoughtful interview.  

Notes/References:

1. Fortman, S., et al. 2013. “Vitamin and Mineral Supplements in the Primary Prevention of Cardiovascular Disease and Cancer: An Updated Systematic Review for the U.S. Preventive Services Task Force. Annals of Internal Medicine,159 (12):824-834. 

2. Guallar, E., et al. 2013. “Enough is Enough. Stop Wasting Money on Vitamin and Mineral Supplements Annals of Internal Medicine,159 (12):850-851-851

3. Autier, P., et al 2014. “Vitamin D status and ill health: a systematic review”. The Lancet Diabetes & Endocrinology, Volume 2, Issue 1, pp 76-89.

4. Bjelakovic, G., et al 2012. “Antioxidant supplements for prevention of mortality in healthy and patients with various diseases”. The Cochorane Library, March, published online.

5. Guillain-Barré syndrome (GBS) is an autoimmune disease that attacks nerves cells causing muscle weakness and often paralysis. According to the CDC, approximately 3000 to 6000 people develop GBS each year in United States. Infection by Campylobacter jenuni, influenza and other infections are risk factors for GBS. More recently, countries with zika virus outbreak reported increased numbers of GBS cases.  For more information, visit the following CDC page: http://www.cdc.gov/flu/protect/vaccine/guillainbarre.htm 

6. Pellagra, scurvy and rickets are caused by deficiency of niacin (vitamin B3), vitamin C, and vitamin D respectively. 

Reflections on Krauss’s The Greatest Story Ever Told—So Far

by Felipe Nogueira

published in Skeptical Briefs Volume 27.2, Summer 2017

In the Summer 2016 issue of Skeptical Briefs, this column featured an interview with theoretical physicist Lawrence Krauss, who briefly mentioned his new popular-science book. The Greatest Story Ever Told—So Far was published by Atria Books in the beginning of March. It’s about the greatest intellectual journey ever taken by humans (so far) from Plato to the discovery of the Higgs’s boson.

Krauss begins by reminding us of Plato’s Allegory of the Cave. As the allegory goes, people live imprisoned inside a cave only seeing its blank wall. The only thing those inside the cave see from the outside world is that wall, which is illuminated by a fire behind them, allowing moving shadows to appear. According to Plato, the prisoners of the cave consider the shadows part of the real world to the point of giving names to them.

This Allegory of the Cave brilliantly introduces the book. As Krauss uncovers through the book, a lot of what we learn about the universe, or the greatest story ever told so far, came from humans’ investigation about the nature of light.

Newton’s curiosity about light, Krauss argues, might have been motivated because it was a gift from God. This is not a mischaracterization, since Newton devoted much more time to writing about the “occult, alchemy, and searching for hidden meanings and codes in the Bible—focusing in particular on the Book of Revelation and mysteries associated with the ancient Temple of Solomon—than he did to writing about physics.” So, Krauss thinks it’s also reasonable to conclude that Newton’s primary interest was in theology.

Regarding light, Newton thought that it was made of individual particles he called “corpuscles.” Other natural philosophers, such as Descartes and Robert Hooke, did not share his view, considering that light was a wave. In their support, when passed through a prism, white light splits into the several different colors of rainbow.

Even against it, some of Newtown’s discoveries about light made more sense with the “wave theory of light.” He discovered, for example, that each color of light has a distinct angle at which it bends when passing through a prism. He also showed that colored light does not change its color, regardless of how many times it passes through a prism. All of this could be explained if white light is indeed a collection of different colors, but not if light is made of different-colored particles (as Newton thought).

The debate persisted for many years involving discoveries that seem unconnected to the nature of light, such as the connection between electricity and magnetism. As Krauss points out, “These two forces seem quite different, yet have odd similarities. Electric charges can attract or repel. So can magnets. Yet magnets always seem to have two poles, north and south, which cannot be isolated, while electric charges can individually be positive or negative.” To connect these forces required the work of Michael Faraday, the greatest experimental physicist of the nineteenth century. Faraday worked for years trying to see if magnetism could induce electricity, which he showed in 1831, allowing us to use electricity the way we do today, changing the world forever:

It is hard to imagine any discovery that is more deeply ingrained in the workings of modern society. But more deeply, what makes his contribution to our story so remarkable is that he discovered a missing piece of the puzzle that changed the way we think about virtually everything in the physical world today, starting with light itself. If Newton was the last of the magicians, Faraday was the last of the modern scientists to live in the dark, regarding light

The mystery of the connection between electricity and magnetism continued until 1865, when Maxwell published his complete set of equations, connecting these two apparently unconnected phenomena together in a formal theory. He also showed that oscillating charges produce an electromagnetic wave. Then, critically, Maxwell calculated the speed of the electromagnetic wave and he found out what was almost identical to the already known speed of light. Light is an electromagnetic wave.

There was a problem, however. Maxwell’s results concerning electromagnetic waves contradicted the properties of motion already established by Galileo many years before. If a ball is thrown with a speed of 10 mph inside a car moving at 15 mph, someone outside the car would measure the speed of the ball to be 25 mph (10 mph plus 15 mph). But what if instead of a ball inside the car, we have an oscillating charge? Maxwell calculated the speed of electromagnetic waves produced by oscillated charges measuring the strength of electricity and magnetism. Then, would someone outside the car measure the speed of electromagnetic waves from the oscillating charge to be different than what someone inside the car observes? If that’s the case, the observers would measure the strength of electricity and magnetism to be different from the other’s, allowing us to tell who is moving and who is not. But Galileo had shown this is impossible; there is no experiment anyone could perform that could tell if one is at rest or moving at a constant speed. Even though it’s a profound implication, Einstein was the one who realized it. The inconsistency is not just a thought experiment or between simple suppositions; both Galileo’s and Maxwell’s results have been verified by experiment. As Krauss remind us all, “rules that have been established on the bases of experiment cannot easily be tossed aside.” That’s why we needed Einstein’s genius to reconcile those notions.

Einstein’s great solution was that, as Krauss explains, “the two different observers must both measure distances and/or times differently from each other in just such a way that light, at least, would traverse that same measured distance in the same measured time for both observers.” In Einstein’s theory of relativity, space and time measurements are observer dependent.

Motion, electricity, magnetism, and relativity are all connected. That is just the beginning. The book continues to detail those hidden realities of our world, connecting in interesting ways many other physical phenomena, from the double-slit experiment and the rise of quantum mechanics (which uncovered the individual particles that light is made of) to unification of electromagnetism and weak force to superconductivity and the Higgs’s boson.

Were it not for the progress of science—reason and experiment, instead of Plato’s pure thought—we would not uncover many parts of the hidden realties; we would still be inside of a Plato’s cave. And the job of scientists, as Krauss argues, is to see what is behind the shadows, separating illusion from reality.

As the title suggests, the story is not finished: “Every day that we discover something new and surprising, the story gets even better,” says Krauss. Every page of the book you turn, it gets better. Krauss certainly has made a great contribution by describing the hidden realities in his fascinating book.