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How to survive social distancing according to science
Social distancing won't be easy, but science shows us how to make it more manageable.
- Social distancing asks us to repress our evolutionary desire for human contact and interaction.
- Experts worry long periods of the practice will have unforeseen consequences on our mental health.
- We look at seven ways to help us mitigate social distancing's harmful effects.
In response to the COVID-19, government and public health officials have asked us to steer clear of each other. Called "social distancing," the idea is to limit the transmission of the disease by lessening the contact we have with people.
To meet this goal, the Centers for Disease Control and Prevention (CDC) has recommended postponing or canceling all mass gatherings; more than 30 states have shuttered school doors; and many cities have closed bars and restaurants.
Experts agree social distancing will help us slow COVID-19's spread, but as reported by Science, others worry it may have unforeseen consequences.
Over an extended period, loneliness and social isolation can increase stress and depression. They can exacerbate physical health problems such as heart diseases. And like coronavirus, they target the older cohorts of our population to injurious effect.
"The coronavirus spreading around the world is calling on us to suppress our profoundly human and evolutionarily hard-wired impulses for connection: seeing our friends, getting together in groups, or touching each other," Nicholas Christakis, a social scientist and physician at Yale University, told Science. "Pandemics are an especially demanding test…because we are not just trying to protect people we know, but also people we do not know or even, possibly, care about."
Social distancing will be our way of life for several weeks, maybe months. Here are seven ways to help us survive this new paradigm.
Understand social distancing
Despite the name, social distancing is really a form of social solidarity.
Most people who catch the disease will have mild to moderate symptoms—including fever, dry cough, fatigue, and sputum production—and they soon recover. Only an estimated 6 percent of people become critically ill and fewer still die. Even so, that leaves millions of people at risk of developing a debilitating case.
To protect these people, we practice social distancing to curb the disease's multiplying factor. As Lou Bloomfield, a physicist at the University of Virginia, explains:
At present, each person with COVID-19 transmits coronavirus to an average of about two to three people. With such a large multiplying factor, we have rapid exponential growth. Because it takes about five days for COVID-19 to develop, the cases are doubling every two or three days. If there are 100 cases today, there will be 200 cases in a couple of days, and a thousand cases in a little over a week. In a month, it will be almost a million cases. Not good.
Those near million cases would then swarm the public health system, severely draining resources and personnel.
To give a sense of how detrimental that could be, the United States only has 2.9 hospital beds per 1,000 citizens—a figure that represents every bed, not just the free ones. Other resources at risk of overuse include ventilators and respirators.
Through social distancing, we can flatten the curve. That doesn't mean that fewer people will get sick; however, the timeline of people contracting the disease elongates. In turn, the health system has more time to treat critical cases before new ones arrive.
"It is better to operate under the pretense that there is transmission in your community already," Syra Madad, a pathogens specialist, told Vox. "There's going to be disruption to daily life, but we want people to feel empowered by this. The decisions you make will ultimately affect the trajectory of this disease."
Keeping a sense of social solidarity in mind, alongside what philosopher Peter Singer calls the expanding circle of moral concern, may help us weather social distancing better than if we feel punished thanks to some abstract graph's extra spiky curve.
The 2009 swine flu pandemic lead to mass hysteria, according to a study conducted at the University of Michigan. The study found that people perceived H1N1 to be even deadlier than the Ebola outbreak in Africa. The truth was the opposite.
The results suggested that as the perception of risk increased—regardless of the change in actual risk—so did feelings of fear and anxiety. And this fear could lead to dangerous social or personal behavior.
"This is dangerous when the virus doesn't exist like with most mass hysteria cases, but it's even more dangerous when we're talking about a real virus that does exist," Jamiee Bell writes for Big Think. "The fear and paranoia around catching the virus lead to panic-purchasing and the spread of misinformation, which furthers the anxiety and fear in the general public."
Already with COVID-19, people have squirreled away doomsday preppers' supplies of toilet paper, paper towels, and hand sanitizer. Worse, snake oil salesmen have begun peddling fake cures that prey on people's fears.
To combat panic, we need to prioritize reason and realism. A good way to manage that is to filter our information ecosystems.
Prioritize expert-driven, reputable sources of information. The best sites for such information include the CDC's coronavirus page, your local health department's website, and the Johns Hopkins Center for Health Security. These should be your primary sources for information on what's happening and what steps to take.
Reputable news outlets like the New York Times and Wall Street Journal are good sources, but limit your exposure. The availability heuristic shows us that we make snap judgments based on how easily information comes to mind.
An oversaturation of news gives us the faulty sense that rare events occur with more frequency than they do. Primary news-driven examples include terrorist attacks, plane crashes, and, of course, pandemics.
Our sense of the world must be balanced by facts and statistics that, while less eye-catching than a front page headline, are in line with reality.
Retrofit your habit loop
With offices closed and schools shuttered, our daily routines are out of whack. This state can leave creatures of habit aimless, anxious, and stir crazy. Thankfully, you can hijack your pre-establish habit loop and retrofit it for social distancing.
Journalist Charles Duhigg has spent much time researching the science of habits. As he explains, the habit loop comes in three parts:
There's first a cue, which is a trigger for behavior. Then the behavior itself, which we usually refer to as a routine, or scientists refer to it as a routine. And then there's the reward. And the reward is actually why the habit happens in the first place, it's how your brain sort of decides, "Should I remember this pattern for the future or not?"
If you now work remotely, stick to your old cues of waking, showering, and putting on pants. Contrary to popular belief, most people who exclusively work at home manage those feats daily. After work, be sure to reward yourself with something that connects your new routine to a sweet dopamine hit.
As a bonus, you can now substitute your morning commute with something more relaxing. A cup of coffee and a good book, perhaps?
Or if you are homeschooling children, develop a schedule that incorporates routine and reward. Follow an hour of reading and workbook immediately with snack time or educational TV. Don't forget to reward lots of indoor work with outdoor excursions on sunny days.
Get outdoors and exercise
Yes, you can still take the little ones outdoors. Remember: the coronavirus spreads person-to-person through respiratory droplets. The high-contact surfaces that those droplets collect on—think tabletops, door handles, elevator buttons, etc.—are noticeably absent on interurban trails.
The outdoors provides a bevy of benefits to offset social distancing's mental cramps. Frequent contact with nature makes people happier, improves their concentration, and helps them heal. It supplies a wholesome regimen of Vitamin D, too. Doctors recommend 120 minutes of nature every week, and you can shoot for this goal in the weeks to come.
The outdoors also provides a people-free gym for those worried about losing their gains. And experts agree: Avoid the gym.
However, as Dr. Neha Chaudhary told the New York Times, you'll want to avoid high-traffic public places whether they are outdoors or not. Unfortunately, these include playgrounds and popular parks.
Make connections how you can
The CDC defines social distancing as avoiding congregate settings and maintaining a distance of approximately 6 feet from others. That's a broad guideline with a lot of wiggle room.
In an interview with the Atlantic, Carolyn Cannusicio, director of research at the Center for Public Health, translates that guidelines as follows: "I would recommend that people minimize social contact, and that means limiting all social engagements. That includes intimate gatherings among friends." However, she notes that there are exceptions:
I think the exception is if two households are in strict agreement that they are also going to reduce all outside contact and then those two households socialize together, to support one another. I can see social and mental-health advantages to that kind of approach.
Similarly, the King County Health Department points out that "social interaction is still vitally important to the mental health of young people." It recommends playdates of 10 or fewer children if children are healthy, physical contact is limited, and the play area isn't crowded.
Others take a more hard-line approach. As Lindsay Thompson, a pediatrician of the University of Florida, told NPR: "I'm personally taking a really strict line. I would say that playdates inherently have a risk—I don't know how big or small. But if we can put them off for a few weeks and replace it with family time, it would be better."
All experts agree that if you are sick, isolation is the best policy. If you must make in-person contact, be mindful of the risks, keep your distance, and follow CDC guidelines for washing your hands, not touching your face, and sneezing in a tissue you immediately throw away.
Many scientific studies have shown a strong correlation between altruistic activities and improved health, happiness, and well-being. A study in Nature Communications found that participants who spent money on others reported greater happiness than a control group who did not. Others have found that regular giving reduces depression while enhancing emotional regulation. Another found that patients reported ameliorated pain after volunteering.
"So much of public health is rightly focused on environmental toxins and the control of epidemics. However, a positive vision of public health must nurture benevolent affect and helping behavior," writes Stephen G. Post.
Social distancing may limit our opportunities for altruistic behavior, but we can get creative. We could, for example, help a high-risk relative or neighbor by offering to do their grocery shopping with our own. This keeps the high-risk individual away from crowded stores, while also lessening the number of people congregating through the aisles.
We could also form a pact with fellow parents to share homeschool responsibilities—provided, as Cannuscio recommends, everyone is healthy and parents maintain a strict agreement to reduce contact elsewhere.
And, of course, there are the traditional donations of time, money, and resources to nonprofits helping others during this difficult time.
Manage your stress
During a pandemic, stress can manifest in many ways, all harmful. Worry about ourselves and loved ones turns into ubiquitous anxiety. Changes in sleep patterns or increased alcohol use can make us tired and irritable. And underlying health conditions can worsen.
We'll need to sharpen our stress management techniques to keep our lives in balance. The CDC recommends setting aside time to unwind, exercise, and engage in activities you enjoy. Be cognizant of your eating habits, substitute alcohol for tea, and connect with others. And when you do have free time, don't spend it glued to breaking news or social media hubs (again, Don't Panic).
The CDC also recommends practicing deep breathing and meditation, which have been shown to have concentration and stress-reduction benefits. As psychologist Daniel Goleman explains:
The good news is that there's a dose-response relationship in meditation. Apparently from what we can tell the longer you do it the more benefits you get. For example, right from the beginning, there are intentional benefits, there are stress benefits, you're more resilient under stress, but we see this even more strikingly in people who have been longer-term meditators.
If your stress-reduction techniques typically involve leaving the house, you may be to escape virtually. Many museums are offering virtual tours to keep homebound minds sharp. The same goes for live performances. The Metropolitan Opera will stream free opera productions while its curtain is down.
Social distancing will prove a trial by fire. Neither humans nor our societies are built with the intention that we live as small, distant lightyears from each other constellations. In addition to the above, we have another strength to draw upon: optimism.
In one study, researchers looked at the "positive health" of the longest detained American POWs of the Vietnam War. The researchers concluded that optimism predicts "positive physical and psychological health" and provides "long-term protective benefits."
And that's a bonus tip for surviving social distancing in the weeks to come.
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Inventions with revolutionary potential made by a mysterious aerospace engineer for the U.S. Navy come to light.
- U.S. Navy holds patents for enigmatic inventions by aerospace engineer Dr. Salvatore Pais.
- Pais came up with technology that can "engineer" reality, devising an ultrafast craft, a fusion reactor, and more.
- While mostly theoretical at this point, the inventions could transform energy, space, and military sectors.
The U.S. Navy controls patents for some futuristic and outlandish technologies, some of which, dubbed "the UFO patents," came to light recently. Of particular note are inventions by the somewhat mysterious Dr. Salvatore Cezar Pais, whose tech claims to be able to "engineer reality." His slate of highly-ambitious, borderline sci-fi designs meant for use by the U.S. government range from gravitational wave generators and compact fusion reactors to next-gen hybrid aerospace-underwater crafts with revolutionary propulsion systems, and beyond.
Of course, the existence of patents does not mean these technologies have actually been created, but there is evidence that some demonstrations of operability have been successfully carried out. As investigated and reported by The War Zone, a possible reason why some of the patents may have been taken on by the Navy is that the Chinese military may also be developing similar advanced gadgets.
Among Dr. Pais's patents are designs, approved in 2018, for an aerospace-underwater craft of incredible speed and maneuverability. This cone-shaped vehicle can potentially fly just as well anywhere it may be, whether air, water or space, without leaving any heat signatures. It can achieve this by creating a quantum vacuum around itself with a very dense polarized energy field. This vacuum would allow it to repel any molecule the craft comes in contact with, no matter the medium. Manipulating "quantum field fluctuations in the local vacuum energy state," would help reduce the craft's inertia. The polarized vacuum would dramatically decrease any elemental resistance and lead to "extreme speeds," claims the paper.
Not only that, if the vacuum-creating technology can be engineered, we'd also be able to "engineer the fabric of our reality at the most fundamental level," states the patent. This would lead to major advancements in aerospace propulsion and generating power. Not to mention other reality-changing outcomes that come to mind.
Among Pais's other patents are inventions that stem from similar thinking, outlining pieces of technology necessary to make his creations come to fruition. His paper presented in 2019, titled "Room Temperature Superconducting System for Use on a Hybrid Aerospace Undersea Craft," proposes a system that can achieve superconductivity at room temperatures. This would become "a highly disruptive technology, capable of a total paradigm change in Science and Technology," conveys Pais.
High frequency gravitational wave generator.
Credit: Dr. Salvatore Pais
Another invention devised by Pais is an electromagnetic field generator that could generate "an impenetrable defensive shield to sea and land as well as space-based military and civilian assets." This shield could protect from threats like anti-ship ballistic missiles, cruise missiles that evade radar, coronal mass ejections, military satellites, and even asteroids.
Dr. Pais's ideas center around the phenomenon he dubbed "The Pais Effect". He referred to it in his writings as the "controlled motion of electrically charged matter (from solid to plasma) via accelerated spin and/or accelerated vibration under rapid (yet smooth) acceleration-deceleration-acceleration transients." In less jargon-heavy terms, Pais claims to have figured out how to spin electromagnetic fields in order to contain a fusion reaction – an accomplishment that would lead to a tremendous change in power consumption and an abundance of energy.
According to his bio in a recently published paper on a new Plasma Compression Fusion Device, which could transform energy production, Dr. Pais is a mechanical and aerospace engineer working at the Naval Air Warfare Center Aircraft Division (NAWCAD), which is headquartered in Patuxent River, Maryland. Holding a Ph.D. from Case Western Reserve University in Cleveland, Ohio, Pais was a NASA Research Fellow and worked with Northrop Grumman Aerospace Systems. His current Department of Defense work involves his "advanced knowledge of theory, analysis, and modern experimental and computational methods in aerodynamics, along with an understanding of air-vehicle and missile design, especially in the domain of hypersonic power plant and vehicle design." He also has expert knowledge of electrooptics, emerging quantum technologies (laser power generation in particular), high-energy electromagnetic field generation, and the "breakthrough field of room temperature superconductivity, as related to advanced field propulsion."
Suffice it to say, with such a list of research credentials that would make Nikola Tesla proud, Dr. Pais seems well-positioned to carry out groundbreaking work.
A craft using an inertial mass reduction device.
Credit: Salvatore Pais
The patents won't necessarily lead to these technologies ever seeing the light of day. The research has its share of detractors and nonbelievers among other scientists, who think the amount of energy required for the fields described by Pais and his ideas on electromagnetic propulsions are well beyond the scope of current tech and are nearly impossible. Yet investigators at The War Zone found comments from Navy officials that indicate the inventions are being looked at seriously enough, and some tests are taking place.
If you'd like to read through Pais's patents yourself, check them out here.
Laser Augmented Turbojet Propulsion System
Credit: Dr. Salvatore Pais
She helped create CRISPR, a gene-editing technology that is changing the way we treat genetic diseases and even how we produce food.
This article was originally published on our sister site, Freethink.
Last year, Jennifer Doudna and Emmanuelle Charpentier became the first all-woman team to win the Nobel Prize in Chemistry for their work developing CRISPR-Cas9, the gene-editing technology. The technology was invented in 2012 — and nine years later, it's truly revolutionizing how we treat genetic diseases and even how we produce food.
CRISPR allows scientists to alter DNA by using proteins that are naturally found in bacteria. They use these proteins, called Cas9, to naturally fend off viruses, destroying the virus' DNA and cutting it out of their genes. CRISPR allows scientists to co-opt this function, redirecting the proteins toward disease-causing mutations in our DNA.
So far, gene-editing technology is showing promise in treating sickle cell disease and genetic blindness — and it could eventually be used to treat all sorts of genetic diseases, from cancer to Huntington's Disease.
The biotech revolution is just getting started — and CRISPR is leading the charge. We talked with Doudna about what we can expect from genetic engineering in the future.
This interview has been lightly edited and condensed for clarity.
Freethink: You've said that your journey to becoming a scientist had humble beginnings — in your teenage bedroom when you discovered The Double Helix by Jim Watson. Back then, there weren't a lot of women scientists — what was your breakthrough moment in realizing you could pursue this as a career?
Dr. Jennifer Doudna: There is a moment that I often think back to from high school in Hilo, Hawaii, when I first heard the word "biochemistry." A researcher from the UH Cancer Center on Oahu came and gave a talk on her work studying cancer cells.
I didn't understand much of her talk, but it still made a huge impact on me. You didn't see professional women scientists in popular culture at the time, and it really opened my eyes to new possibilities. She was very impressive.
I remember thinking right then that I wanted to do what she does, and that's what set me off on the journey that became my career in science.
CRISPR 101: Curing Sickle Cell, Growing Organs, Mosquito Makeovers | Jennifer Doudna | Big Think www.youtube.com
Freethink: The term "CRISPR" is everywhere in the media these days but it's a really complicated tool to describe. What is the one thing that you wish people understood about CRISPR that they usually get wrong?
Dr. Jennifer Doudna: People should know that CRISPR technology has revolutionized scientific research and will make a positive difference to their lives.
Researchers are gaining incredible new understanding of the nature of disease, evolution, and are developing CRISPR-based strategies to tackle our greatest health, food, and sustainability challenges.
Freethink: You previously wrote in Wired that this year, 2021, is going to be a big year for CRISPR. What exciting new developments should we be on the lookout for?
Dr. Jennifer Doudna: Before the COVID-19 pandemic, there were multiple teams around the world, including my lab and colleagues at the Innovative Genomics Institute, working on developing CRISPR-based diagnostics.
"Traits that we could select for using traditional breeding methods, that might take decades, we can now engineer precisely in a much shorter time."
DR. JENNIFER DOUDNA
When the pandemic hit, we pivoted our work to focus these tools on SARS-CoV-2. The benefit of these new diagnostics is that they're fast, cheap, can be done anywhere without the need for a lab, and they can be quickly modified to detect different pathogens. I'm excited about the future of diagnostics, and not just for pandemics.
We'll also be seeing more CRISPR applications in agriculture to help combat hunger, reduce the need for toxic pesticides and fertilizers, fight plant diseases and help crops adapt to a changing climate.
Traits that we could select for using traditional breeding methods, that might take decades, we can now engineer precisely in a much shorter time.
Freethink: Curing genetic diseases isn't a pipedream anymore, but there are still some hurdles to cross before we're able to say for certain that we can do this. What are those hurdles and how close do you think we are to crossing them?
Dr. Jennifer Doudna: There are people today, like Victoria Gray, who have been successfully treated for sickle cell disease. This is just the tip of the iceberg.
There are absolutely still many hurdles. We don't currently have ways to deliver genome-editing enzymes to all types of tissues, but delivery is a hot area of research for this very reason.
We also need to continue improving on the first wave of CRISPR therapies, as well as making them more affordable and accessible.
Freethink: Another big challenge is making this technology widely available to everyone and not just the really wealthy. You've previously said that this challenge starts with the scientists.
Dr. Jennifer Doudna: A sickle cell disease cure that is 100 percent effective but can't be accessed by most of the people in need is not really a full cure.
This is one of the insights that led me to found the Innovative Genomics Institute back in 2014. It's not enough to develop a therapy, prove that it works, and move on. You have to develop a therapy that actually meets the real-world need.
Too often, scientists don't fully incorporate issues of equity and accessibility into their research, and the incentives of the pharmaceutical industry tend to run in the opposite direction. If the world needs affordable therapy, you have to work toward that goal from the beginning.
Freethink: You've expressed some concern about the ethics of using CRISPR. Do you think there is a meaningful difference between enhancing human abilities — for example, using gene therapy to become stronger or more intelligent — versus correcting deficiencies, like Type 1 diabetes or Huntington's?
Dr. Jennifer Doudna: There is a meaningful distinction between enhancement and treatment, but that doesn't mean that the line is always clear. It isn't.
There's always a gray area when it comes to complex ethical issues like this, and our thinking on this is undoubtedly going to evolve over time.
What we need is to find an appropriate balance between preventing misuse and promoting beneficial innovation.
Freethink: What if it turns out that being physically stronger helps you live a longer life — if that's the case, are there some ways of improving health that we should simply rule out?
Dr. Jennifer Doudna: The concept of improving the "healthspan" of individuals is an area of considerable interest. Eliminating neurodegenerative disease will not only massively reduce suffering around the world, but it will also meaningfully increase the healthy years for millions of individuals.
"There is a meaningful distinction between enhancement and treatment, but that doesn't mean that the line is always clear. It isn't."
DR. JENNIFER DOUDNA
There will also be knock-on effects, such as increased economic output, but also increased impact on the planet.
When you think about increasing lifespans just so certain people can live longer, then not only do those knock-on effects become more central, you also have to ask who is benefiting and who isn't? Is it possible to develop this technology so the benefits are shared equitably? Is it environmentally sustainable to go down this road?
Freethink: Where do you see it going from here?
Dr. Jennifer Doudna: The bio revolution will allow us to create breakthroughs in treating not just a few but whole classes of previously unaddressed genetic diseases.
We're also likely to see genome editing play a role not just in climate adaptation, but in climate change solutions as well. There will be challenges along the way both expected and unexpected, but also great leaps in progress and benefits that will move society forward. It's an exciting time to be a scientist.
Freethink: If you had to guess, what is the first disease you think we are most likely to cure, in the real world, with CRISPR?
Dr. Jennifer Doudna: Because of the progress that has already been made, sickle cell disease and beta-thalassemia are likely to be the first diseases with a CRISPR cure, but we're closely following the developments of other CRISPR clinical trials for types of cancer, a form of congenital blindness, chronic infection, and some rare genetic disorders.
The pace of clinical trials is picking up, and the list will be longer next year.
A school lesson leads to more precise measurements of the extinct megalodon shark, one of the largest fish ever.
- A new method estimates the ancient megalodon shark was as long as 65 feet.
- The megalodon was one of the largest fish that ever lived.
- The new model uses the width of shark teeth to estimate its overall size.
A Florida student figured out a way to more accurately measure the size of one of the largest fish that ever lived – the extinct megalodon shark – and found that it was even larger than previously estimated.
The megalodon (officially named Otodus megalodon, which means "Big Tooth") lived between 3.6 and 23 million years ago and was thought to be about 34 feet long on average, reaching the maximum length of 60 feet. Now a new study puts that number at up to 65 feet (20 meters).
Homework assignment leads to a discovery
The study, published in Palaeontologia Electronica, used new equations extrapolated from the width of megalodon's teeth to make the improved estimates. The paper's lead author, Victor Perez, developed the revised methodology while he was a doctoral student at the Florida Museum of Natural History. He got the idea while teaching students, noticing a range of discrepancies in the results they were getting.
Students were supposed to calculate the size of megalodon based on the ancient fish's similarities to the modern great white shark. They utilized the commonly accepted method of linking the height of a shark's tooth to its total body length. As the press release from the Florida Museum of Natural History expounds, this method involves locating the anatomical position of a tooth in the shark's jaw, measuring the tooth "from the tip of the crown to the line where root and crown meet," and using that number in an appropriate equation.
But while carrying out calculations in this way, some of Perez's students thought the shark would have been just 40 feet long, while others were calculating 148 feet. Teeth located toward the back of the mouth were yielding the largest estimates.
"I was going around, checking, like, did you use the wrong equation? Did you forget to convert your units?" said Perez, currently the assistant curator of paleontology at the Calvert Marine Museum in Maryland. "But it very quickly became clear that it was not the students that had made the error. It was simply that the equations were not as accurate as we had predicted."
Found in North Carolina, these 46 fossils are the most complete set of megalodon teeth ever excavated.Credit: Jeff Gage/Florida Museum
The new approach
Perez's math exercise demonstrated that the equations in use since 2002 were generating different size estimates for the same shark based on which tooth was being measured. Because megalodon teeth are most often found as standalone fossils, Perez focused on a nearly complete set of teeth donated by a fossil collector to design a new approach.
Perez also had help from Teddy Badaut, an avocational paleontologist in France, who suggested using tooth width instead of height, which would be proportional to the length of its body. Another collaborator on the revised method was Ronny Maik Leder, then a postdoctoral researcher at the Florida Museum, who aided in the development of the new set of equations.
The research team analyzed the widths of fossil teeth that came from 11 individual sharks of five species, which included megalodon and modern great white sharks, and created a model that connects how wide a tooth was to the size of the jaw for each species.
"I was quite surprised that indeed no one had thought of this before," shared Leder, who is now director of the Natural History Museum in Leipzig, Germany. "The simple beauty of this method must have been too obvious to be seen. Our model was much more stable than previous approaches. This collaboration was a wonderful example of why working with amateur and hobby paleontologists is so important."
Why use teeth?
In general, almost nothing of the super-shark survived to this day, other than a few vertebrae and a large number of big teeth. The megalodon's skeleton was made of lightweight cartilage that decomposed after death. But teeth, with enamel that preserves very well, are "probably the most structurally stable thing in living organisms," Perez said. Considering that megalodons lost thousands of teeth during a lifetime, these are the best resources we have in trying to figure out information about these long-gone giants.
Researchers suggest megalodon's large jaws were very thick, made for grabbing prey and breaking its bones, exerting a bite force of up to 108,500 to 182,200 newtons.
Megalodon tooth compared to two great white shark teeth. Credit: Brocken Inaglory / Wikimedia.
Limitations of the new model
While the new model is better than previous methods, it's still far from perfect in precisely figuring out the sizes of animals which lived so long ago and left behind few if any full remains. Because individual sharks come in a variety of sizes, Perez warned that even their new estimates have an error range of about 10 feet when it comes to the largest animals.
Other ambiguities may affect the results, such as the width of the megalodon's jaw and the size of the gaps between its teeth, neither of which are accurately known. "There's still more that could be done, but that would probably require finding a complete skeleton at this point," Perez pointed out.
How did the megalodon go extinct?
Environmental changes that led to fluctuations in sea levels and disturbed ecosystems in the oceans likely led to the demise of these enormous ancient sharks. They were just too big to be sustained by diminishing food resources, says the ReefQuest Centre for Shark Research.
A 2018 study suggested that a supernova 2.6 million years ago hit Earth's atmosphere with so much cosmic energy that it resulted in climate change. The cosmic rays that included particles called muons might have caused a mass extinction of giant ocean animals ("the megafauna") that included the megalodon by causing mutations and cancer.
Scientists, led by Adrian Melott, professor emeritus of physics and astronomy at the University of Kansas, estimated that "the cancer rate would go up about 50 percent for something the size of a human — and the bigger you are, the worse it is. For an elephant or a whale, the radiation dose goes way up," as he explained in a press release.