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Do You Have Too Many Facebook Friends?
The average Facebook user now has about 338 friends, though the median number is quite a bit lower: 200. This means that while half of all Facebook users have 200 or fewer friends, many of the billion-plus Facebookers have quite a few more. In fact, 15 percent of users have friend lists topping 500. That’s a lot of virtual acquaintances, but consider that Facebook lets you keep piling on the friends until you hit a ceiling of 5000—about the population of Milton, Wisconsin.
For most of us, 5000 Facebook friends will sound like way too many. But where is the tipping point? According to Robin Dunbar, an Oxford University anthropologist who studies social networks, any grouping larger than about 150 starts to strain the cognitive capacity of the human brain. Basing this figure (dubbed “Dunbar’s Number” in the 1990s) on research into the brains and social habits of primates, Dunbar argues that we cannot effectively manage relationships with many hundreds of people. This goes for real-world friends as well as online relations:
"The interesting thing is that you can have 1,500 friends, but when you actually look at traffic on sites, you see people maintain the same inner circle of around 150 people that we observe in the real world," Dunbar told the London-based Sunday Times. "People obviously like the kudos of having hundreds of friends but the reality is that they're unlikely to be bigger than anyone else's."
This finding suggests that it doesn’t really matter how many friends you accept into your online communities: the number of people you actually interact with will stay constant. The phenomenon is a bit like having three dozen sweaters in your closet: chances are you probably have a half-dozen favorites that see the most daylight. But too many friends, like too many sweaters, can clutter up your life. Extraneous clothing takes up space in your bureau and extraneous friends clog your newsfeed. It may not seem like a major problem to encounter the odd kitten photo from a high-school friend you don’t quite remember when you log on to Facebook, but add up all those irrelevant kitten posts over number of friends and time spent hitting the down-arrow on your keyboard, and you start to see how your brain may be bombarded with tons of irrelevant information.
For Maria Konnikova, writing at the New Yorker, there may be a more significant downside:
With social media, we can easily keep up with the lives and interests of far more than a hundred and fifty people. But without investing the face-to-face time, we lack deeper connections to them, and the time we invest in superficial relationships comes at the expense of more profound ones. We may widen our network to two, three, or four hundred people that we see as friends, not just acquaintances, but keeping up an actual friendship requires resources. “The amount of social capital you have is pretty fixed,” Dunbar said. “It involves time investment. If you garner connections with more people, you end up distributing your fixed amount of social capital more thinly so the average capital per person is lower.” If we’re busy putting in the effort, however minimal, to “like” and comment and interact with an ever-widening network, we have less time and capacity left for our closer groups.
Konnikova notes Dunbar’s estimate that “we spend sixty per cent of our time” with close circles of friends and spend forty percent with our wider sphere of 150. “Social networks may be growing our base, and, in the process, reversing that balance,” she writes.
Is Facebook messing with our intimacy balance, as Konnikova suggests? If the site is taking us away from meaningful relationships with our family and closest friends and thrusting us into hours of diddling in an online “community” not worthy of the name, we really do have something to worry about. Some Facebook users may be trading face-to-face time for face-to-screen time, depriving themselves of the benefits of real human interaction: talking, touching, simply being with friends and loved ones.
I think these worries are a bit overblown. Yes, the digital age has probably pushed us too far toward interaction with devices. Yes, family dinners and walks in nature should be gadget-free zones to give people a chance to escape the pings and glare of our smartphones. But Facebook is not the only culprit drawing us to leer downward at the smartphone screen. Email is almost certainly the biggest one, haunting us day and night. (Clive Thompson has one interesting proposal to ease that burden.) General web browsing is another.
And Facebook is arguably the best place one might turn while thumbing around on a little screen, if you use it smartly. Think about it: the social networking site is useful in tons of ways that go well beyond scrolling through kitten or omelette photos. First, of course, Facebook lets you “like” a page—Big Think or The Economist, for example, or the American Civil Liberties Union. This means you’ll get updates in your newsfeed whenever these sites share a post or article. It’s (almost) like subscribing to a magazine or joining a social organization. Second, you can form your own groups and then communicate easily and seamlessly with a class or a bowling league or circles of cousins planning a family reunion. That makes communication with intimates easy and efficient (and much more effective than group emails and “reply to all”); these groups can facilitate better and more frequent face-to-face interactions in the real world. And yes, you can keep in some kind of touch with friends from many disparate moments and places in your life: the high school friend in Seattle and the grad school friend in Hattiesburg, the fellow traveler you met once in Switzerland and the former student teaching English in Costa Rica. You might not have the neural bandwith to do justice to all these online relationships, and you would be doing some violence to relationships with your family and face-to-face connections if you were to try, but when you want or need to make a connection, the conduit is right there waiting for you.
In the end, I'm not convinced that my in-person relationships are doomed by my 1100+ Facebook friends. Nor am I worried that my brain is overly taxed by having ten times the number of virtual contacts that the Dunbar Number specifies. Facebook isn't really a community, so it doesn't compete in a zero-sum game with church or school, family or grass-roots organization. Facebook is, more than anything, a series of resources to help organize and promote real-world social circles. So I'd say pile on the virtual friends, if you like. Just don't try to keep tabs on all of them all at once.
Image credit: Shutterstock
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 non-contact technique could someday be used to lift much heavier objects — maybe even humans.
- Since the 1980s, researchers have been using sound waves to move matter through a technique called acoustic trapping.
- Acoustic trapping devices move bits of matter by emitting strategically designed sound waves, which interact in such a way that the matter becomes "trapped" in areas of particular velocity and pressure.
- Acoustic and optical trapping devices are already used in various fields, including medicine, nanotechnology, and biological research.
Sound can have powerful effects on matter. After all, sound strikes our world in waves — vibrations of air molecules that bounce off of, get absorbed by, or pass through matter around us. Sound waves from a trained opera singer can shatter a wine glass. From a jet, they can collapse a stone wall. But sound can also be harnessed for delicate interactions with matter.
Since the 1980s, researchers have been using sound to move matter through a phenomenon called acoustic trapping. The method is based on the fact that sound waves produce an acoustic radiation force.
"When an acoustic wave interacts with a particle, it exerts both an oscillatory force and a much smaller steady-state 'radiation' force," wrote the American Physical Society. "This latter force is the one used for trapping and manipulation. Radiation forces are generated by the scattering of a traveling sound wave, or by energy gradients within the sound field."
When tiny particles encounter this radiation, they tend to be drawn toward regions of certain pressure and velocity within the sound field. Researchers can exploit this tendency by engineering sound waves that "trap" — or suspend — tiny particles in the air. Devices that do this are often called "acoustic tweezers."
Building a better tweezer
A study recently published in the Japanese Journal of Applied Physics describes how researchers created a new type of acoustic tweezer that was able to lift a small polystyrene ball into the air.
Tweezers of Sound: Acoustic Manipulation off a Reflective Surface youtu.be
It is not the first example of a successful "acoustic tweezer" device, but the new method is likely the first to overcome a common problem in acoustic trapping: sound waves bouncing off reflective surfaces, which disrupts acoustic traps.
To minimize the problems of reflectivity, the team behind the recent study configured ultrasonic transducers such that the sound waves that they produce overlap in a strategic way that is able to lift a small bit of polystyrene from a reflective surface. By changing how the transducers emit sound waves, the team can move the acoustic trap through space, which moves the bit of matter.
Move, but don't touch
So far, the device is only able to move millimeter-sized pieces of matter with varying degrees of success. "When we move a particle, it sometimes scatters away," the team noted. Still, improved acoustic trapping and other no-contact lifting technologies — like optical tweezers, commonly used in medicine — could prove useful in many future applications, including cell separation, nanotechnologies, and biological research.
Could future acoustic-trapping devices lift large and heavy objects, maybe even humans? It seems possible. In 2018, researchers from the University of Bristol managed to acoustically trap particles whose diameters were larger than the sound wavelength, which was a breakthrough because it surpassed "the classical Rayleigh scattering limit that has previously restricted stable acoustic particle trapping," the researchers wrote in their study.
In other words, the technique — which involved suspending matter in tornado-like acoustic traps — showed that it is possible to scale up acoustic trapping.
"Acoustic tractor beams have huge potential in many applications," Bruce Drinkwater, co-author of the 2018 study, said in a statement. "I'm particularly excited by the idea of contactless production lines where delicate objects are assembled without touching them."
Australian parrots have worked out how to open trash bins, and the trick is spreading across Sydney.
- If sharing learned knowledge is a form of culture, Australian cockatoos are one cultured bunch of birds.
- A cockatoo trick for opening trash bins to get at food has been spreading rapidly through Sydney's neighborhoods.
- But not all cockatoos open the bins; some just stay close to those that do.
Dumpster-diving trash parrots
In a study about these smart birds just published in Science, researchers define animal culture as "population-specific behaviors acquired via social learning from knowledgeable individuals."
Co-lead author of the study Barbara Klump of the Max Planck Institute of Animal Behavior in Konstanz, Germany says, "[C]ompared to humans, there are few known examples of animals learning from each other. Demonstrating that food scavenging behavior is not due to genetics is a challenge."
An opportunity presented itself in a video that co-author Richard Major of the Australian Museum shared with Klump and the other co-authors. In the video, a sulphur-crested cockatoo used its beak to pull up the handle of a closed garbage bin — using its foot as a wedge — and then walked back the lid sufficiently to flip it open, exposing the bin's edible contents.
Major has been studying Cacatua galerita for 20 years and says, "Like many Australian birds, sulphur-crested cockatoos are loud and aggressive." The study describes them as a "large-brained, long-lived, and highly social parrot." Says Major, "They are also incredibly smart, persistent, and have adapted brilliantly to living with humans."(Research regarding some of the ways in which wild animals adapt to the presence of humans has already produced some fascinating results and is ongoing.)
Clever cockie opens bin - 01 youtu.be
The researchers became curious about how widespread this behavior might be and saw a research opportunity. After all, says John Martin, a researcher at Taronga Conservation Society, "Australian garbage bins have a uniform design across the country, and sulphur-crested cockatoos are common across the entire east coast."
Martin continues, "In 2018, we launched an online survey in various areas across Sydney and Australia with questions such as, 'What area are you from, have you seen this behavior before, and if so, when?'"
Word gets around
Credit: magspace/Adobe Stock
Although the cockatoos' maneuver was reported in only three suburbs before 2018, by the end of 2019, people in 44 areas reported observing the behavior. Clearly, more and more cockatoos were learning how to successfully dumpster dive.
As further proof, says Klump, "We observed that the birds do not open the garbage bins in the same way, but rather used different opening techniques in different suburbs, suggesting that the behavior is learned by observing others." One individual bird in north Sydney invented its own method, and the scientists saw it grow in popularity throughout the local population.
To track individual birds, the researchers marked 500 cockatoos with small red dots. Subsequent observations revealed that not all cockatoos are bin-openers. Only about 10 percent of them are, and they are mostly males. The other cockatoos apparently restrict their education to a different lesson: hang around with a bin-opener, and you will get supper.
Thanks to the surveys, the researchers consider the entire project to be a valuable citizen-science experiment. "By studying this behavior with the help of local residents, we are uncovering the unique and complex cultures of their neighborhood birds."
The few seconds of nuclear explosion opening shots in Godzilla alone required more than 6.5 times the entire budget of the monster movie they ended up in.