Biology students aim for fast, portable Ebola test

Rostam Zafari and Brian Goldstone have made a video appeal to support their idea.

By Kimber Williams, Emory Report

Two Emory freshmen have turned a classroom challenge into an exercise in real-life social entrepreneurship, advancing their idea to create a new method of testing for the Ebola virus into an online crowdfunding campaign that is already gaining steam.

The result? A student-powered proposal to develop REDS, Rapid Ebola Detection Strips, a portable, fast, less expensive, user-friendly approach to detecting the virus in the field.

It was on the first day of classes this semester, during an Introduction to Biology course, that Brian Goldstone and Rostam Zafari heard Senior Biology Lecturer Rachelle Spell mention a way to earn extra-credit: Learn how doctors currently test for the Ebola virus and come up with a faster, more affordable idea.

Read the full story.

Doing math with movie stars

Emory mathematician Ken Ono, left, coaches actor Dev Patel for his portrayal of the math genius Ramanujan, on the set of "The Man Who Knew Infinity." (Photos by Sam Pressman.)

By Carol Clark

Emory mathematician Ken Ono did not plan for his career to veer into the movie business. Unexpected paths can open, however, when your work involves unraveling the trail of mysteries left by Srinivasa Ramanujan. The Indian math genius had little formal education, but filled notebook after notebook with fantastic formulas that he said were visions from a Hindu goddess.

While British colonialism was still at its height, English mathematician G.H. Hardy helped Ramanujan become a scholar at Cambridge University, where he dazzled and baffled professors. Ramanujan died in 1920 at the age of 32, leaving behind many extraordinary contributions to math, along with big questions about the proofs underlying his work.

The film is based on a 1991 book

Ono is among those who’ve cracked some of these questions: Most notably, the realization in 2011 that partition numbers are fractals, an insight that opened a theoretical window onto “seeing” their infinitely repeating superstructure. Ono’s team also devised the first finite formula for calculating the partitions of any number.

In July, Ono received a request from film director Matt Brown in London to chat over Skype about a biopic he was working on. “The Man Who Knew Infinity,” produced by Stillwater Pictures, will feature Dev Patel as Ramanujan and Jeremy Irons as Hardy.

Ono happily agreed to the Skype session. The next thing he knew, he was flying to London to serve as an on-the-scene consultant during filming at Pinewood Studios.

In the following Q&A, eScienceCommons talks with Ono about what it’s like for a mathematician to get swept up into the production of a major motion picture.

eScienceCommons: What did you and Matt Brown talk about during that Skype session? 

Ken Ono: I had gone to India in 2012 to work on a docu-drama about Ramanujan by an Indian film company. Matt had seen that short movie, and he knew that as part of that project I had gotten to actually hold Ramanujan’s original notebooks and go through them. For his movie, Matt wanted me to advise the art department to ensure the props were accurate. And also to make sure that the script had all the math details right. The problem with the partition numbers raised by Ramanujan is a key part of the script and Matt said he found it fascinating that mathematicians still hadn’t cracked that mystery. I told him, “Actually, I led the team that solved that problem a couple of years ago.”

His response was: “You need to come to England tomorrow, if you can!”

I was already planning to compete in the World Triathlon Championships in Germany in two weeks, so I agreed to just go to Europe early and spend that time in London.

Working with the art department to get every detail right. "All of the math in this movie will be absolutely accurate," Ono says. 

eSC: What was your first day of work like? 

Ono: A driver came and picked me up from my London hotel in a BMW. I’m definitely not accustomed to having my own personal driver! Pinewood Studios is in a rural area. We traveled through pastures with cows grazing in them and then, out of nowhere, you see these gigantic buildings. 

The art department for the film is amazing. They were reproducing artifacts related to Ramanujan in fanatical detail, including 100-year-old issues of mathematical journals and an 11-page letter he wrote to Hardy. One person’s job was to master Ramanujan’s handwriting and replicate it. They had more than 400 photos taken from reconnaissance trips to various places and they asked me what it was like to be in Ramanujan’s home, which I had visited when I was in India.

Kevin McNally, left, is portraying British mathematician Major McMahon. "McNally played Mr. Gibbs in 'Pirates of the Caribbean' and he would do this pirate fist bump," Ono says. "I'm not sure what it means."

eSC: How did you wind up actually working with the actors? 

Ono: The second day when I arrived at the studio Matt Brown said, “We need you to come to rehearsal.” So suddenly I found myself in a room witnessing two world-class actors, Dev Patel and Jeremy Irons, recreating one of the greatest stories of math, and one that has been the basis of my career. It was a huge thrill.

I was the only mathematician present and I was helping to both get the math right and tweak the dialog to maximize the impact of each scene. A big part of the movie is how Ramanujan and Hardy learn to understand each other so they can work together. Their cultures and their methods of doing math are in conflict.

In a scene soon after Ramanujan arrives in England, Hardy is trying to get him to write down a proof to one of his formulas. But Ramanujan received his formulas as complete visions and thought it was a waste of time to write down proofs of things he already knew. I explained to the actors that there is a difference between a claim, or a formula, and a proof. For trained mathematicians, a proof is necessary, it gives value to a statement. Ramanujan eventually realized why it’s important to prove things, that even he can make a mistake.

Taking a break from filming, from left: Producer Ed Pressman, Jeremy Irons, Dev Patel, Ken Ono, Matt Brown and actress Sorel Carradine.

Another key part of the movie is Ramanujan and Hardy working together to find a good approximation for the partition numbers. These numbers grow at an astronomical rate. I described what it’s like for two mathematicians to be working at a board, trying to figure something out. I wanted the actors to know that when you finally are confident that you have a method to find the answer, that’s the “aha” moment, not the dotting of the i’s that comes later. We wanted the audience to really feel what it meant to get closer and closer to a theorem. Ramanujan had an idea and Hardy had the technical expertise required to write it out.

It's pivotal when Hardy realizes that they have found a way to approximate the partition numbers. We needed a line of dialogue to describe his excitement over this insight into these numbers that keep growing so rapidly. We couldn’t use the word “trillions” because it wasn’t part of the British vernacular in the early 18th century.

I suggested the line, “Ramanujan, you are truly the man who knows infinity.” It both makes mathematical sense and it worked the name of the name of the movie into the script.

When we finally got all of the details of the scene right, and Jeremy Irons read that line in his magical voice, the feeling was electric!

A letter from Ramanujan to Hardy is among the many props painstakingly reproduced by the art department for the film.

eSC: What’s your favorite scene of those that you worked on? 

Ono: One scene that I am quite fond of shows Ramanujan sitting in a class of students at Cambridge looking absolutely bored as a professor discusses a math problem. The professor resents having this lowly Indian in his class. And Ramanujan is not even taking notes, which is infuriating to him. So he challenges Ramanujan to complete a formula. Ramanujan walks to the board and instantly writes it out. 

My job was to come up with a formula for the scene that makes sense in terms of the topic of the class. It also had to be complex enough to be impressive, but simple enough so that it would not be too difficult for Dev Patel to easily remember it and write it down quickly.

I chose a special decimal expansion for Pi, which involves having the odd numbers in order by means of a special fraction that Ramanujan knew. Ramanujan saw beautiful patterns in numbers and I wanted the math for the scene to reflect that. The formula had to look pleasing to the eye, so whether you were an expert or not you could sense this beautiful symmetry that represents Ramanujan’s talent.

Between takes: "Jeremy Irons' attention to detail is amazing," Ono says.

eSC: How did the actors react to having a mathematician working with them? 

Ono: I was referred to as “the guy who cracked partitions” all over the set. Dev Patel did a hilarious, over-the-top impression of me talking about math. I didn’t realize I got so excited.

He is only 24, very humble and super smart, although he’ll tell you that he’s bad at math. He’s a great actor and fun person. Someone took a video of he and I running across a campus green, and then kept playing it backwards.

It was mostly, however, very serious hard work and really long days. The actors were really down-to-earth and focused.

Jeremy Irons’ attention to detail is amazing. He now knows that Pi(x) is not always less than Li(x). We discussed partitions, Skewe’s number, PNT and the Old English ways of pronouncing huge numbers. 

For one scene, Hardy barges into the vice chancellor of the university’s office, to tell him that he must not reject Ramanujan for a Royal Society fellowship. Irons was wearing a top coat and a hat and before each take for this 15-second scene he would walk fast in a circle about 20 times. Then he knocks on the door.

When I asked why he did that, he explained that walking in circles changed his face slightly and said, “Acting angry is the easy part. Convincing the audience that I just ran across campus in a huff is much harder.”

Irons even practiced Hardy’s handwriting using a 1930s-era fountain pen. The movie opens with Hardy writing this very special speech about Ramanujan that he delivered at Harvard: “I’m charged with the task today of telling you one of the most romantic and peculiar stories in the history of math.”

I almost cried when we were filming that. I knew the speech well and, on top of that, to hear it spoken in Jeremy Irons’ voice was incredible.

eSC: Now that you have your own IMDb page, will you be leaving math for the movies? 

Ono: I’ll definitely be sticking to math. Making movies is a lot harder! It’s grueling work but I also had a wonderful time. I signed some autographs one night just because I was sitting next to Dev Patel and Jeremy Irons in a swanky restaurant. I still can’t believe that they are making this movie and that I got to be involved. It’s so awesome that math is now hip!

Related:
New theories reveal the nature of numbers
Math formula gives new glimpse into the magical mind of Ramanujan

'I first became a scientist in my backyard'

That’s me, climbing a flagpole just outside my house when I was about seven years old, circa 1967. The rest of my family was standing below watching, cheering me on, and documenting the event. Little did I know at the time that other kids were told they couldn’t climb flagpoles, let alone make it to the top. Yes, that’s a metaphor.

By Anthony Martin

Emory paleontologist Anthony Martin wrote a moving, personal piece about his path from poverty to a PhD for his blog "Life Traces of the Georgia Coast." Below is an excerpt from Martin's article:

"I first became a scientist in my backyard. This path to life-long inquiry began when I was four years old, as soon as my family moved to a larger house, and one with a larger yard. This small, outdoor patch of land with a few large trees, bushes, and grass soon became my field area, laboratory, classroom, and all-purpose place for conducting experiments in nature. Even better, my proclivity for observing this world outside of myself was encouraged – or at least tolerated – by my mother and father.

"At the time, I had no idea just how important of a role this backyard and parental support would play in my scientific career. Yet now I look back on it with a mix of gratitude and wistfulness, especially as both of my parents have departed this earth I have studied for most of my life. ...

"For about nine months of any given year during my childhood, starting in the spring, I could step out the back door of my house and watch ants, bees, wasps, butterflies, moths, spiders, and praying mantises. Plant-insect interactions in particular – such as pollination, herbivory, and wound responses in plants – drew me in, teaching me those ecological principles long before I ever heard the words 'pollination,' 'herbivory, and 'wound response.'"

Read the whole article on "Life Traces of the Georgia Coast." It's an amazing story.

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Bringing to life "Dinosaurs Without Bones"

Understanding China's housing bubble

Apartments in Shanghai: As China has rapidly grown into the second largest economy in the world, one sector it has focused on is real estate and construction.

The Wall Street Journal wrote about a paper co-authored by an Emory economist titled "The Great Housing Boom of China," which was recently published by the St. Louis Fed. Below is an excerpt from the WSJ article:

"A lot of things about China’s housing bubble don’t make sense. How could housing prices continue to rise sharply and investors continue to make money while vacancies are rising, too? Shouldn’t more vacancies mean less profits? Or, looked from a different point of view, shouldn’t rising profits mean that people are clamoring for apartments, so there should be fewer vacancies?

"Economists Kaiji Chen of Emory University and Yi Wen of St. Louis Federal Reserve tackled this issue in a recent working paper. What they found is that that credit bubbles have a logic all their own. When developing nations go through a big spurt of growth as a result of a transformation of the economy—in the case of China, when a state-owned economy turned into a largely private-owned one—gobs of money flow into the real estate market.

"That pushes up prices and profits as investors keep bidding up property. But it also pushes up vacancies because buyers aren’t purchasing property to live in; they are buying apartments as speculative purchases."

Read more in the Wall Street Journal.

Photo by Catherine Roy

What is a psychopath?

By Carol Clark

Sir Francis Burton was a 19th-century British scholar, soldier, author, spy, poet, diplomat, adventurer and explorer who was lauded for his knowledge of languages and cultures and for being one of the first Europeans to visit the Great Lakes of Africa.

Was he also a psychopath?

Sir Francis Burton

Emory psychologist Scott Lilienfeld and two of his graduate students, Sarah Francis Smith and Ashley Watts, drew on the life story of Burton and others for their article “On the Trail of the Successful Psychopath,” published recently in The Psychologist.

Modern-day scholars, the authors write, have noted that Burton displayed many of the traits of so-called “successful psychopathy,” also known as “adaptive psychopathy.”

A constellation of characteristics is associated with psychopathy, including superficial charm, dishonesty, narcissism, lack of remorse, lack of empathy, physical fearlessness, social boldness and relative immunity to anxiety.

The authors describe how Burton often traveled to areas full of turmoil and dangerous enemies, and he reported feeling “quite jolly” about killing another person. In addition, Burton’s obituary stated that he was known for “telling tales about himself that had no foundation in fact.”

“Perhaps in response to recent economic and social disasters, such as the United States housing market crash in 2008, the Enron scandal and Bernie Madoff’s Ponzi schemes, the concept of successful psychopathy has become the subject of increasing interest to researchers and the general public alike,” the authors write.

“In fact, we know surprisingly little about how prevalent psychopaths are in the business world, whether they’re more likely to attain positions of power, and what they’re like as bosses,” Lilienfeld says.

Psychopaths can seem completely “normal,” and can be hard to detect, even by those who study the disorder in depth, he adds.

"Hollywood has shaped the popular perception of psychopathy more than anything else," says psychologist Scott Lilienfeld. Above, Jack Nicholson portrays the charismatic criminal Randle McMurphy in "One Flew Over the Cuckoo's Nest."

Following are five common myths about psychopaths: 

Myth 1: Psychopathy is a general term for severe mental illness. “’Psychopathy is a very specific type of mental disorder, it is not the same as mental illness in general,” Lilienfeld says. “In fact, ironically, classic psychopaths are less likely to develop many mental illnesses like severe depression or severe anxiety disorders because they probably don’t have much capacity for emotional distress.”

Myth 2: Psychopaths are always violent. “It is true that psychopathy increases the risk for violent behavior to some degree, but that increased risk tends to be only modest,” Lilienfeld says. “Most psychopaths are not particularly violent and the substantial majority of violent people are not especially psychopathic.”



Myth 3: Serial killers are always psychopaths. “Many, if not most, serial killers are not markedly psychopathic,” Lilienfeld says. “And we certainly know that the overwhelming majority of psychopaths are not serial killers.”

Myth 4: Psychopathy is similar to psychosis. “People who are psychotic are out of touch with reality. They typically don’t know the difference between right and wrong,” Lilienfeld says. “Psychopaths, in contrast, are almost always quite rational. They can even reason through moral problems quite well. That reasoning just doesn’t necessarily translate into their actual behaviors.”

Myth 5: Psychopathy is a basis for an insanity defense. “The primary basis for an insanity defense is some variant of not knowing the difference between right and wrong,” Lilenfeld says. “Psychopaths will almost always fail that cognitive prong because they do know the difference between right and wrong in nearly all cases.”

Related:
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Grandiose narcissism reflects U.S. presidents' bright and dark sides

Patterns etched in sound

“I’m into beautiful melodies and catchy harmonies,” says Robert Schneider, the co-founder of The Elephant 6 Recording Company and lead singer and songwriter in the band The Apples in Stereo. “As a producer, I’m also interested in surrounding my pop songs with experimental sounds. These sorts of things are very appealing to me.”

In a recent TEDxEmory talk, Schneider explains how music led him to become a Woodruff Graduate Fellow in Emory’s Department of Mathematics and Computer Science. His research focuses mainly on analytic number theory, but he also has created music compositions based on mathematics.

“I found as I started to study mathematics that there were all these beautiful patterns that were lying there,” he says. “It was like music that was silent, just waiting to be written out and used for compositions.”

Watch the video to learn more, and listen to some of Schneider’s mathematical compositions.

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He took the psychedelic pop path to math

Neuro-Interventions and the Law: Experts to explore ethics and efficacy

Atlanta's Neuro-Interventions and the Law Conference will grapple with thorny issues facing today's legal system. The case of British computer scientist Alan Turing, who submitted to chemical castration in 1952 to avoid imprisonment for homosexuality, exemplifies why a judicial system should take the long view before resorting to drugs or other medical means to alter a person's behavior and biology. Benedict Cumberbatch, above, portrays Turing in the upcoming movie "The Imitation Game."

By Carol Clark

Alan Turing was a hero. He was a mathematician who played a key role in the development of computer science and artificial intelligence and, during World War II, he led Britain’s German code-breaking team, cracking secret messages that gave the Allies an edge in critical battles against the Nazis.

Turing was also a homosexual. In 1952 he was prosecuted for having a sexual relationship with another man, a crime at that time in the United Kingdom. In order to avoid prison, Turing underwent chemical castration: Injections of a drug that took away his libido, while also causing him to have enlarged breasts. His death two years later from cyanide poisoning was ruled a suicide.

The Turing tragedy is just one of many examples of a legal neuro-intervention: The use of a drug or other medical means to change someone’s behavior – sometimes permanently. Despite a problematic past record, a range of such interventions are poised to expand within the legal system and could even become routine.

The conference Neruo-Interventions and the Law: Regulating Human Mental Capacity will gather leading legal scholars, judges, ethicists, neuroscientists and psychologists at Georgia State University September 12-14 to grapple with some of the thorny legal issues being spurred by advances in neuroscience. Registration is free, but there is limited seating.

“Techniques to diagnose and manipulate human behavior and the brain are becoming increasingly sophisticated,” says Paul Root Wolpe, a bioethicist and director of the Emory Center for Ethics, who will give the introductory remarks for the conference. “We need to develop processes and regulations for how we’re going to use these techniques because they are not going away. In fact, many of them are already in use in criminal proceedings.”

The conference is the first major event of the Atlanta Neuroethics Consortium. The Emory Center for Ethics spearheaded the formation of the consortium, which brings together a range of resources from metro-Atlanta’s universities, biotechnology sector and non-profit organizations to explore the implications as neuroscience is set to transform every aspect of our lives, from medicine, to law and civil society.

At least nine U.S. states, including Georgia, have incorporated versions of chemical castration into their laws for those convicted of child sex crimes. While pedophilia is an extreme taboo, critics of chemical castration have called it “cruel and unusual punishment.”

Even if convicted sex offenders are given a voluntary option of a drug treatment in lieu of imprisonment, the ethics are problematic, Wolpe says. “From a government perspective, it would be infinitely cheaper to use drugs instead of incarceration to fix a criminal problem. That kind of incentive would add to the risk of abuse of the power to drug people.”

Another problematic area that Wolpe cites: The practice of drugging criminal defendants suffering from schizophrenia or other mental illnesses so that they achieve a “synthetic competency” to stand trial and, if convicted, perhaps even be executed.

Attorneys are increasingly calling for brain scans as evidence in criminal trials. Traumatic brain injury, or TBI, for instance, is associated with impulsiveness, anger and aggression. Should people diagnosed with TBI receive special consideration if they commit a violent criminal offense?

About 12 percent of U.S. veterans returning from combat in Iraq and Afghanistan suffer from at least mild TBI, according to the Department of Defense. Should vets accused of violent acts be treated differently than other defendants with similar brain injuries?

These questions and dozens of others will be brought up in the conference talks, papers and panel discussions.

It’s important to involve a range of expertise to sort through the complicated neuroethics involved in all of these issues, Wolpe says. “History shows that, over and over again, society has allowed moral suppositions to infiltrate scientific thinking. Years from now, we don’t want to be looking back and saying, ‘How could they have done that?’”

Related:
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Southern bodies: A review of 'Sex, Sickness and Slavery'
Nazi eugenics versus the American Dream

Curbing pesticide threats to bees

Berry Brosi, a bee biologist in Emory's department of environmental sciences, wrote an opinion piece for the Atlanta Journal Constitution on the importance of making informed choices about the use of pesticides. Following is an excerpt from the article:

"Bee populations are declining and several culprits contribute: parasites and diseases, pesticides, lack of flowering plants to feed on and management practices. Scientists, conservationists, government agencies and beekeepers are working hard to figure out ways to reduce these challenging problems.

"One concrete action we can take is to reduce exposure to pesticides that can harm bees and other pollinators. Recently, Emory University announced that it will take an important step toward protecting bees by banning a class of pesticides known as 'neonicotinoids.'

"Though relatively new on the market, neonicotinoids are the most used class of insecticides on Earth. ... Scientific evidence has been mounting from a range of studies that neonicotinoids are particularly damaging to bees. ... Even at low concentrations neonicotinoids can impair bee immune systems, learning, foraging and navigation."

Read the whole article in the Atlanta Journal Constitution.

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Photo: iStockphoto.com

Modern population boom traced to pre-industrial roots

By the end of the Roman Empire, humanity had crossed a critical threshold of social organization that allowed more people to take advantage of economies of scale, says anthropologist Aaron Stutz. "The Consummation of  Empire," by Thomas Cole, portrays the wealth and culture of the period.

By Carol Clark

The foundation of the human population explosion, commonly attributed to a sudden surge in industrialization and public health during the 18th and 19th centuries, was actually laid as far back as 2,000 years ago, suggests an extended model of detailed demographic and archeological data.

The Public Library of Science One (PLOS ONE) recently published the analytical framework developed by Aaron Stutz, an associate professor of anthropology at Emory’s Oxford College.

“The industrial revolution and public health improvements were proximate reasons that more people lived longer,” Stutz says. “If you dig further in the past, however, the data suggest that a critical threshold of political and economic organization set the stage 1,500 to 2,000 years ago, around the start of the Common Era. The resulting political-economic balance was the tipping point for economies of scale: It created a range of opportunities enabling more people to get resources, form successful families, and generate enough capital to transfer to the next generation.”

Population dynamics have been a hot topic since 1798, when English scholar Thomas Robert Malthus published his controversial essay that population booms in times of plenty will inevitably be checked by famine and disease. “The power of population is indefinitely greater than the power in the earth to produce subsistence for man,” he wrote. The so-called Malthusian Catastrophe theory was penned just prior to the global census size reaching one billion.

Around 1800, the human population reached one billion. "The First Birthday Party," by Frederick Daniel Hardy, celebrates the strong intergenerational ties that helped make this milestone possible.

While it took hundreds of thousands of years for humans to reach that one billion milestone, it took only another 120 years for humanity to double to two billion. And during the past 50 years, the human population has surged to near eight billion.

“It’s mind-boggling,” Stutz says. “The human population has not behaved like any other animal population. We haven’t stayed in any kind of equilibrium with what we would consider a typical ecological niche.”

Economic historians and demographers have focused on societal changes that occurred during the Industrial Revolution as the explanation for this super-exponential population growth. An archeologist by training, Stutz wanted to explore further back in time.

“Archeologists are interested in looking at much earlier changes in human society,” Stutz says. “In addition to looking at data, we dig up things like people’s houses, community courtyards, agricultural fields, harbors and so on. That gives us this sort of holistic view of how human society and the environment influence one another over time.”

During the Roman Empire, "a huge swath of the population was feeding, quite literally, the dynamism that was taking place," Stutz says. "Thumbs Down," by Jean-Leon Gerome, dramatizes just how cruel and capricious life could be for the individual.

His analysis found that that the potential for the human population to burgeon despite environmental degradation, conflict and disease could be traced to a subtle interaction between competition and organization. At a certain tipping point, this interaction created opportunities for individuals to gain more control over their lives and prosper, opening the door to economies of scale.

Stutz cites the Roman Empire, which spanned 500 years, from just before the Common Era to 476 CE, as a classic example of passing through this threshold. One of the largest and most prosperous empires in history, it is noteworthy for economic and political organization, literature, and advances in architecture and engineering. And yet, on an individual level, life was not necessarily so grand. Farm laborers and miners were ground into short, miserable lives to produce all those surplus goods for trading and empire building. And large numbers of young males had to serve in the military to ward off rebellions.

“The vast majority of people who lived under Roman rule had a life expectancy into their late 20s or early 30s,” Stutz says. “A huge swath of the population was feeding, quite literally, the dynamism that was taking place in terms of economic and political development. Their labor increased the potential for providing more democracy and competition on the smaller scale. That, in turn, led to a more complex, inter-generational dynamic, making it possible to better care for offspring and even transfer resources to them.”

A modern-day garment factory in Southeast Asia echoes the Industrial Revolution. "We might wind up being back in a situation where a growing part of the population is basically providing labor to sustain a minority," Stutz says.

The tipping point had been reached, Stutz says, and the trend continued despite the collapse of the Roman Empire. “The increasingly complex and decentralized economic and political entities that were built up around the world from the beginning of the Common Era to 1500 CE created enough opportunities for individuals, states and massive powers like England, France and China to take advantage of the potential for economies of scale,” Stutz says.

This revised framework for the underpinnings of human population dynamics could lead to better understanding of how economic and political organization is affecting modern-day society, he adds.

“We might wind up being back in a situation where a growing part of the population is basically providing labor to sustain a minority,” Stutz says. “You could certainly point to the sweat shops in the developing world. Another potential example is the growing income inequality that’s been well-documented in the United States over the last couple of decades.”

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