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Why large groups of people often come to the same conclusions
Study confirms the existence of a special kind of groupthink in large groups.
- Large groups of people everywhere tend to come to the same conclusions.
- In small groups, there's a much wider diversity of ideas.
- The mechanics of a large group make some ideas practically inevitable.
People make sense of the world by organizing things into categories and naming them. "These are circles." "That's a tree." "Those are rocks." It's one way we tame our world. There's a weird correspondence between different cultures, though — even though we come from different places and very different circumstances, cultures everywhere develop largely the same categorizations.
"But this raises a big scientific puzzle," says Damon Centola of the University of Pennsylvania. "If people are so different, why do anthropologists find the same categories, for instance for shapes, colors, and emotions, arising independently in many different cultures? Where do these categories come from and why is there so much similarity across independent populations?"
Centola is the senior investigator of a new study in the journal Nature Communications from the Network Dynamics Group (NDG) at the Annenberg School for Communication that explores how such categorization happens.
Some have theorized that these categories are innate—pre-wired in our brains—but the study says "nope." Its authors hypothesize that it has more to do with the dynamics of large groups, or networks.
The grouping game
Some of the shapes used in the experiment
Credit: Guilbeault, et al./University of Pennsylvania
The researchers tested their theory with 1,480 people playing an online "Grouping Game" via Amazon's Mechanical Turk platform. The individuals were paired with another participant or made a member of a group of 6, 8, 24, or 50 people. Each pair and group were tasked with categorizing the symbols shown above, and they could see each other's answers.
The small groups came up with wildly divergent categories—the entire experiment produced nearly 5,000 category suggestions—while the larger groups came up with categorization systems that were virtually identical to each other.
Says Centola, "Even though we predicted it, I was nevertheless stunned to see it really happen. This result challenges many long-held ideas about culture and how it forms."
Nor was this unanimity a matter of having teamed-up like-minded individuals. "If I assign an individual to a small group," says lead author Douglas Guilbeault, "they are much more likely to arrive at a category system that is very idiosyncratic and specific to them. But if I assign that same individual to a large group, I can predict the category system that they will end up creating, regardless of whatever unique viewpoint that person happens to bring to the table."
Why this happens
The many categories suggested by small groups on the left, the few from large groups on the right
Credit: Guilbeault, et al./Nature Communications
The striking results of the experiment correspond to a previous study done by NDG that investigated tipping points for people's behavior in networks.
That study concluded that after an idea enters a discussion among a large network of people, it can gain irresistible traction by popping up again and again in enough individuals' conversations. In networks of 50 people or more, such ideas eventually reach critical mass and become a prevailing opinion.
The same phenomenon does not happen often enough within a smaller network, where fewer interactions offer an idea less of an opportunity to take hold.
The study's finding raises an interesting practical possibility: Would categorization-related decisions made by large groups be less likely to fall prey to members' individual biases?
With this question in mind, the researchers are currently looking into content moderation on Facebook and Twitter. They're investigating whether the platforms would be wiser when categorizing content as free speech or hate speech if large groups were making these decisions instead of lone individuals working at these companies.
Similarly, they're also exploring the possibility that larger networks of doctors and healthcare professionals might be better at making diagnoses that would avoid biases such as racism or sexism that could cloud the judgment of individual practitioners.
"Many of the worst social problems reappear in every culture," notes Centola, "which leads some to believe these problems are intrinsic to the human condition. Our research shows that these problems are intrinsic to the social experiences humans have, not necessarily to humans themselves. If we can alter that social experience, we can change the way people organize things, and address some of the world's greatest problems."
All this from a wad of gum?
- Researchers recently uncovered a piece of chewed-on birch pitch in an archaeological dig in Denmark.
- Conducting a genetic analysis of the material left in the birch pitch offered a plethora of insights into the individual who last chewed it.
- The gum-chewer has been dubbed Lola. She lived 5,700 years ago; and she had dark skin, dark hair, and blue eyes.
Five thousand and seven hundred years ago, "Lola" — a blue-eyed woman with dark skin and hair — was chewing on a piece of pitch derived from heating birch bark. Then, this women spit her chewing gum out into the mud on an island in Denmark that we call Syltholm today, where it was unearthed by archaeologists thousands of years later. A genetic analysis of the chewing gum has provided us with a wealth of information on this nearly six-thousand-year-old Violet Beauregarde.
This represents the first time that the human genome has been extracted from material such as this. "It is amazing to have gotten a complete ancient human genome from anything other than bone," said lead researcher Hannes Schroeder in a statement.
"What is more," he added, "we also retrieved DNA from oral microbes and several important human pathogens, which makes this a very valuable source of ancient DNA, especially for time periods where we have no human remains."
In the pitch, researchers identified the DNA of the Epstein-Barr virus, which infects about 90 percent of adults. They also found DNA belonging to hazelnuts and mallards, which were likely the most recent meal that Lola had eaten before spitting out her chewing gum.
Insights into ancient peoples
The birch pitch was found on the island of Lolland (the inspiration for Lola's name) at a site called Syltholm. "Syltholm is completely unique," said Theis Jensen, who worked on the study for his PhD. "Almost everything is sealed in mud, which means that the preservation of organic remains is absolutely phenomenal.
"It is the biggest Stone Age site in Denmark and the archaeological finds suggest that the people who occupied the site were heavily exploiting wild resources well into the Neolithic, which is the period when farming and domesticated animals were first introduced into southern Scandinavia."
Since Lola's genome doesn't show any of the markers associated with the agricultural populations that had begun to appear in this region around her time, she provides evidence for a growing idea that hunter-gatherers persisted alongside agricultural communities in northern Europe longer than previously thought.
Her genome supports additional theories on northern European peoples. For example, her dark skin bolsters the idea that northern populations only recently acquired their light-skinned adaptation to the low sunlight in the winter months. She was also lactose intolerant, which researchers believe was the norm for most humans prior to the agricultural revolution. Most mammals lose their tolerance for lactose once they've weaned off of their mother's milk, but once humans began keeping cows, goats, and other dairy animals, their tolerance for lactose persisted into adulthood. As a descendent of hunter-gatherers, Lola wouldn't have needed this adaptation.
A hardworking piece of gum
A photo of the birch pitch used as chewing gum.
These findings are encouraging for researchers focusing on ancient peoples from this part of the world. Before this study, ancient genomes were really only ever recovered from human remains, but now, scientists have another tool in their kit. Birch pitch is commonly found in archaeological sites, often with tooth imprints.
Ancient peoples used and chewed on birch pitch for a variety of reasons. It was commonly heated up to make it pliable, enabling it to be molded as an adhesive or hafting agent before it settled. Chewing the pitch may have kept it pliable as it cooled down. It also contains a natural antiseptic, and so chewing birch pitch may have been a folk medicine for dental issues. And, considering that we chew gum today for no other reason than to pass the time, it may be that ancient peoples chewed pitch for fun.
Whatever their reasons, chewed and discarded pieces of birch pitch offer us the mind-boggling option of learning what someone several thousands of years ago ate for lunch, or what the color of their hair was, their health, where their ancestors came from, and more. It's an unlikely treasure trove of information to be found in a mere piece of gum.
The Inglehart-Welzel World Cultural map replaces geographic accuracy with closeness in terms of values.
- This map replaces geography with another type of closeness: cultural values.
- Although the groups it depicts have familiar names, their shapes are not.
- The map makes for strange bedfellows: Brazil next to South Africa and Belgium neighboring the U.S.
Some countries value self-expression more than others.Credit: Robyn Beck / AFP via Getty Images
Question: On what map is Lithuania a neighbor of China, Poland lies next to Brazil, and Morocco and Yemen touch?
Answer: The Inglehart-Welzel World Cultural Map. To be precise, the 2017 map. Because on the 2020 version, each of those pairs has drifted apart significantly.
These are not, strictly speaking, maps but rather scatterplot diagrams. Each dot represents a country, the position of which is based on how it ranks on two different values (discussed below). The dots are corralled together into geo-cultural groups:
- Catholic Europe, which comprises countries as diverse and far apart as Hungary and Andorra■ Protestant Europe, taking in both Iceland and Germany
- The Orthodox world, from Belarus all the way to Armenia
- The three Baltic states
- The English-speaking world, including both the U.S. and Northern Ireland
- The huge African-Islamic world, ranging from Azerbaijan to South Africa
- Latin America, which goes from Mexico to Argentina
- South Asia, which comprises both India and Cyprus
- The Confucian world, encompassing China and Japan.
The placement of the dots indicates cultural proximity or distance. Some countries from different groups can be more similar than other countries in the same group.
See the examples indicated above: cultural neighbors China and Lithuania belong to the Confucian and Baltic groups, respectively. Poland is part of Catholic Europe; its 2017 neighbor Brazil is in Latin America. Morocco and Yemen are closer culturally to Armenia, in the Orthodox group, than they are to Qatar, despite all belonging to the African-Islamic group.
The 2017 version of the map places Malta deep inside South America and lets Vietnam, Portugal, and Macedonia meet.Credit: World Values Survey, public domain.
Creating a culture map
So, what exactly are the criteria used for plotting these dots in the first place?
These maps are part of the World Values Survey, first conducted by political scientist Ronald Inglehart in the late 1990s. With his colleague Christian Welzel, he produced an update in 2005. The WVS has been revised several times since, most recently in 2020.
The WVS asserts that there are two fundamental dimensions to cross-cultural variation across the world. These are used as the axes to plot the various countries on the diagram.
- The X-axis measures survival versus self-expression values.
Survival values focus on economic and physical security. There is not much room for trust and tolerance of "others." Self-expression values prioritize well-being, quality of life, and self-expression. There is more room for tolerating ethnic, religious, and sexual minorities.
- The Y-axis measures traditional versus secular-rational values.
Traditional values include deference to religion and parental authority as well as traditional social and family values. Societies that score high on traditions typically also are highly nationalistic. In more secular-rational societies, science and bureaucracy replace faith as the basis for authority. Secular-rational values include high tolerance of things like divorce, abortion, euthanasia, and suicide.
As indicated by the significant changes on the 2020 map, the cultural values of nations are not static:
- Countries that move up on the map are shifting from traditional to more secular-rational values.
- Countries that move to the right on the map are shifting from survival values to self-expression values.
- And, of course, vice versa in both cases.
According to the authors of the map, changes in cultural outlook can be the result of socioeconomic changes — increasing levels of wealth, for example. But the religious and cultural heritage of each country also plays a part.
The world's cultural landscape is dynamic — you could even say promiscuous, producing new bedfellows every few years.Credit: World Values Survey, public domain.
Some notable features of the 2020 map:
- The Baltic group has been dissolved; Lithuania is now part of Catholic Europe, Estonia a lone Protestant island in a Catholic sea. More worryingly, Latvia seems to have dissolved completely.
- In general, survival values are strongest in African-Islamic countries, self-expression values in Protestant Europe.
- Traditional values are strongest in African-Islamic countries and Latin America, while secular values dominate in Confucian countries and Protestant Europe.
- The United States is an atypical member of the English-speaking group, scoring much lower on both scales (that is to say, lower and more to the left). In other words, the U.S. is more into traditional and survival values than the group's other members.
- Shifting attitudes don't just separate; they also unite. Belgium and the U.S. are now culture buddies, as are New Zealand and Iceland. Kazakhstan is virtually indistinguishable from Bosnia.
The Inglehart-Welzel map is not without its critics. It has been decried as Eurocentric, simplistic, and culturally essentialist (that is, the assumption that certain cultural characteristics are essential and fixed, and that some are superior to others). Which is, of course, a very self-expressive thing to say.
For more on these maps, on the WVS surveys, and on the methodology used, visit the World Values Survey.
Strange Maps #1098
Got a strange map? Let me know at email@example.com.
A study finds that baby mammals dream about the world they are about to experience to prepare their senses.
- Researchers find that babies of mammals dream about the world they are entering.
- The study focused on neonatal waves in mice before they first opened their eyes.
- Scientists believe human babies also prime their visual motion detection before birth.
Imagine opening your eyes for the first time as a brand new baby. The world is so mysterious, full of obstacles and strange shapes. And yet it does not take babies all that long to get their bearings, to latch on to their parents, and to start interacting. How do they do this so quickly? A new study published in Science proposes that babies of mammals dream about the world they are about to enter before being born, developing important skills.
The team, led by professor Michael Crair, who specializes in neuroscience, ophthalmology, and visual science, wanted to understand why when mammals are born, they are already somewhat prepared to interact with the world.
"At eye opening, mammals are capable of pretty sophisticated behavior," said Craig, "But how do the circuits form that allow us to perceive motion and navigate the world? It turns out we are born capable of many of these behaviors, at least in rudimentary form."
Unusual retinal activity
The scientists observed waves of activity radiating from the retinas of newborn mice before their eyes first open. Imaging shows that soon after birth, this activity disappears. In its place matures a network of neural transmissions that carries visual stimuli to the brain, as explained by a Yale press release. Once it reaches the brain, the information is encoded for storage.
What's particularly unusual about this neonatal activity is that it demonstrates a pattern that would happen if the animal was moving forward somewhere. As the researchers write in the study, "Spontaneous waves of retinal activity flow in the same pattern as would be produced days later by actual movement through the environment."
Crair explained that this "dream-like activity" makes sense from an evolutionary standpoint, as it helps the mouse get ready for what will happen to it after it opens its eyes. It allows the animal to "respond immediately to environmental threats," Crair shared.
Retinal waves in a newborn mouse prepare it for vision www.youtube.com
What is creating the waves?
The scientists also probed what is responsible for creating the retinal waves that mimic the forward motion. They turned on and off the functionality of starburst amacrine cells — retinal cells that release neurotransmitters — and discovered that blocking them stopped the retinal waves from flowing, which hindered the mouse from developing the ability to react to visual motion upon birth. These cells are also important to an adult mouse, affecting how it reacts to environmental stimuli.
Graphic showing the origin and functionality of directional retinal waves.Michael C. Crair et al, Science, 2021.
What about human babies?
While the study focused on mice, human babies also seem to be able to identify objects and motion right after birth. This suggests the presence of a similar phenomenon in babies before they are born.
"These brain circuits are self-organized at birth and some of the early teaching is already done," Crair stated. "It's like dreaming about what you are going to see before you even open your eyes."