Month: August 2016

We’ve been wrong about the origins of life for 90 years

By Arunas L Radzvilavicius, UCL.

For nearly nine decades, science’s favorite explanation for the origin of life has been the “primordial soup”. This is the idea that life began from a series of chemical reactions in a warm pond on Earth’s surface, triggered by an external energy source such as lightning strike or ultraviolet (UV) light. But recent research adds weight to an alternative idea, that life arose deep in the ocean within warm, rocky structures called hydrothermal vents.

A study published last month in Nature Microbiology suggests the last common ancestor of all living cells fed on hydrogen gas in a hot iron-rich environment, much like that within the vents. Advocates of the conventional theory have been sceptical that these findings should change our view of the origins of life. But the hydrothermal vent hypothesis, which is often described as exotic and controversial, explains how living cells evolved the ability to obtain energy, in a way that just wouldn’t have been possible in a primordial soup.

Under the conventional theory, life supposedly began when lightning or UV rays caused simple molecules to join together into more complex compounds. This culminated in the creation of information-storing molecules similar to our own DNA, housed within the protective bubbles of primitive cells. Laboratory experiments confirm that trace amounts of molecular building blocks that make up proteins and information-storing molecules can indeed be created under these conditions. For many, the primordial soup has become the most plausible environment for the origin of first living cells.

But life isn’t just about replicating information stored within DNA. All living things have to reproduce in order to survive, but replicating the DNA, assembling new proteins and building cells from scratch require tremendous amounts of energy. At the core of life are the mechanisms of obtaining energy from the environment, storing and continuously channelling it into cells’ key metabolic reactions.

Did life evolve around deep-sea hydrothermal vents?
U.S. National Oceanic and Atmospheric Administration/Wikimedia Commons

Where this energy comes from and how it gets there can tell us a whole lot about the universal principles governing life’s evolution and origin. Recent studies increasingly suggest that the primordial soup was not the right kind of environment to drive the energetics of the first living cells.

It’s classic textbook knowledge that all life on Earth is powered by energy supplied by the sun and captured by plants, or extracted from simple compounds such as hydrogen or methane. Far less known is the fact that all life harnesses this energy in the same and quite peculiar way.

This process works a bit like a hydroelectric dam. Instead of directly powering their core metabolic reactions, cells use energy from food to pump protons (positively charged hydrogen atoms) into a reservoir behind a biological membrane. This creates what is known as a “concentration gradient” with a higher concentration of protons on one side of the membrane than other. The protons then flow back through molecular turbines embedded within the membrane, like water flowing through a dam. This generates high-energy compounds that are then used to power the rest of cell’s activities.

Life could have evolved to exploit any of the countless energy sources available on Earth, from heat or electrical discharges to naturally radioactive ores. Instead, all life forms are driven by proton concentration differences across cells’ membranes. This suggests that the earliest living cells harvested energy in a similar way and that life itself arose in an environment in which proton gradients were the most accessible power source.

Vent hypothesis

Recent studies based on sets of genes that were likely to have been present within the first living cells trace the origin of life back to deep-sea hydrothermal vents. These are porous geological structures produced by chemical reactions between solid rock and water. Alkaline fluids from the Earth’s crust flow up the vent towards the more acidic ocean water, creating natural proton concentration differences remarkably similar to those powering all living cells.

The studies suggest that in the earliest stages of life’s evolution, chemical reactions in primitive cells were likely driven by these non-biological proton gradients. Cells then later learned how to produce their own gradients and escaped the vents to colonise the rest of the ocean and eventually the planet.

While proponents of the primordial soup theory argue that electrostatic discharges or the Sun’s ultraviolet radiation drove life’s first chemical reactions, modern life is not powered by any of these volatile energy sources. Instead, at the core of life’s energy production are ion gradients across biological membranes. Nothing even remotely similar could have emerged within the warm ponds of primeval broth on Earth’s surface. In these environments, chemical compounds and charged particles tend to get evenly diluted instead of forming gradients or non-equilibrium states that are so central to life.

Deep-sea hydrothermal vents represent the only known environment that could have created complex organic molecules with the same kind of energy-harnessing machinery as modern cells. Seeking the origins of life in the primordial soup made sense when little was known about the universal principles of life’s energetics. But as our knowledge expands, it is time to embrace alternative hypotheses that recognise the importance of the energy flux driving the first biochemical reactions. These theories seamlessly bridge the gap between the energetics of living cells and non-living molecules.

The ConversationArunas L Radzvilavicius, , UCL

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

Virtual bodyswapping reduces bias against other races

By Manos Tsakiris, Royal Holloway.

In 1959, John Howard Griffin, a white American writer, underwent medical treatments to change his skin appearance and present himself as a black man. He then traveled through the segregated US south to experience the racism endured daily by millions of black Americans. This unparalleled life experiment provided invaluable insights into how the change in Griffin’s own skin color triggered negative and racist behaviors from his fellow Americans.

But what about the changes that Griffin himself might have experienced? What does it mean to become someone else? How does this affect one’s self? And how can this affect one’s stereotypes, beliefs and racial attitudes? That was the key question that my colleagues and I set out to answer in a series of psychological experiments that looked at the link between our bodies and our sense of who we are.

Is this my body?

Can I trick you into thinking that a fake hand is part of your body? When I ask my students or friends, the immediate reaction I get is one of disbelief, followed by a definite “no.“ However, we’ve learned from experimental psychology that it’s actually quite easy to trick your brain into thinking that a fake hand is indeed part of you.

Watch a subject experiencing the rubber hand illusion.

The Rubber Hand Illusion, as it came to be known, is based on a simple mechanism of sensory integration that shows how malleable the sense of our body is. As a participant in my experiment, I would ask you to sit in front of a table and place your right hand behind a screen so that you cannot directly see it. I would then place a prosthetic rubber hand in front of you and ask you to look at it. Now the trick is that with two paintbrushes I start stroking gently your own hand, while simultaneously stroking the rubber hand at exactly the same location. In this way, you feel touch in your own hand, which you cannot see, and you see touch on the fake hand.

A light-skinned participant experiences a dark hand as part of his own body. Trends in Cognitive Sciences, Maister et al.,  CC BY

This situation creates a conflict for the brain, precisely because you feel something in one location and see something very similar – the touch on the fake hand – in a different location. Brains don’t like conflicts, and your brain will try to solve the conflict by using the sensory information available. Since we tend to put more stock in what we see, your brain will start creating the illusion that the sensation you feel in your own hand is actually caused by the touch you see on the fake hand. If this is the origin of your sensation, thenthe fake hand must be yours!

The illusion is strong and some of its effects are remarkable. For example, it has been shown that once you experience the illusion, the skin temperature on your hand drops, suggesting that the brain downregulates the homeostasis of your own hand since it now has a new hand to take care of. Interestingly, we also found that people experience the illusion independent of differences in skin color between their own hand and the rubber hand. These striking findings inspired us to ask some important questions about the ways in which we relate socially to other people.

Changing bodies

Walking down the street, our attention is constantly and automatically attracted to other people, especially their faces and appearance; these are very salient social stimuli. Additionally, we’re capable of making split-second decisions about others – whether we like them or not, whether we would trust them or not, whether they are similar to us or not, and by extension whether they belong to the same group as us or not.

Such decisions often influence and to a certain extent bias our behavior towards them. For example, we tend to trust people more who we perceive to be physically similar to us. The same goes for perceived similarity in personality traits. It seems that our brain constantly computes the perceived physical or psychological similarity between self and others to gauge our behavior.

What if you could, for a moment have the body of another race, sex or age compared to your own? Would that make you perceive people of another race, sex or age as more similar to you? Would that change the way you feel about yourself or the way that you stereotype different social groups? By combining illusions – including the Rubber Hand Illusion – that change the way our brain represents our body, we were able to test whether a change in your self would result in a change in your implicit racial bias.

We did not want explicitly to ask our participants whether they were racist because we could easily anticipate their answers. Instead, we used a well known social psychological test, the Implicit Association Test or IAT for short. It’s designed to measure the strength of association between different categories, such as Black or White people and pleasant or unpleasant concepts.

One screen participants would see in an IAT about race.They’re asked to sort the face to the left or the right.
Manos Tsakiris, Author provided

In the typical IAT procedure, the word “Black” appears in the top left corner of the screen and the word “White” appears in the top right corner. In the middle of the screen a “Black” or a “White” face appears and participants must sort the face into the appropriate category by pressing the appropriate left or right key. In addition to faces, other positive or negative attributes can also be used.

We can measure how fast people are at categorizing black faces when these are paired with unpleasant or pleasant concepts. If people hold negative implicit attitudes towards black people, they should have strong associations between unpleasant concepts and black faces. As a result, they should be faster at categorizing black faces when these are paired with unpleasant concepts, and should be slower when black faces are paired with pleasant concepts. We can therefore measure people’s performance in the IAT and estimate how negatively or positively biased they are against black people.

In a series of studies that we run in my lab as well as in the lab of Prof Mel Slater, we first used this simple test to measure the implicit racial bias in large samples of white Caucasian adult participants. As expected, they showed small but nevertheless negative biases towards black people. Next, we used different kinds of bodily illusions to make people experience that they have a body of dark skin color. For example, participants experienced that their hand, their face or their whole body in a virtual reality environment was black.

A woman feels the sensation she sees happening to a different face.

Once they experienced the illusion of having a different body, we gave them again the same test of implicit bias. For white people who were made to feel that they had black bodies, their negative biases against black people diminished. In similar experiments, adults who felt as if they had children’s bodies processed perceptual information and aspects of themselves as being more child-like.

Changing minds

One basic function that underlies many of our social interactions is computing the perceived physical or psychological similarity between ourselves and others. By changing how people represent themselves internally, we probably allowed them to experience others as being more similar to them. This in turn resulted in a reduction in their negative implicit biases.

In other words, the integration of different sensory signals can allow the brain to update its model of the body and cause people to change their attitudes about others.

Often formed at an early age, negative racial attitudes are thought to remain relatively stable throughout adulthood. Few studies have looked into whether implicit social biases can change. The converging evidence that we report shows that we can positively alter such biases by exploiting the way the brain integrates sensory information from our bodies. Such findings can motivate new research into how self-identity is constructed and how the boundaries between ingroups and outgroups might be altered.

Immersive virtual reality enhances the illusion of embodying a different body.
Trends in Cognitive Sciences, Maister et al., CC BY

From a societal point of view, our methods and findings might help us understand how to approach phenomena such as racism, racial and religious hatred, and gender inequality and discrimination. There is no simple cure for racism, of course. But together with the increased accessibility of virtual reality technologies, our experiments can be easily transformed into engaging educational tools that could allow participants to experience the world from the perspective of someone different from themselves.

This feeling of being a different person or a member of a different group allows us to understand that “we are more alike… than we are unalike,“ as Maya Angelou famously wrote. How can such changes be effected in society? This is a fundamental political question, one that has not been answered for some thousand years now, but experiencing the world through someone else’s body might be a small but important step towards more integration.

The ConversationManos Tsakiris, Professor of Psychology, Royal Holloway

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

As Rio bay waters show, we badly need innovation in treating human wastes

By Daniele Lantagne, Tufts University.

In the months leading up to the Rio Olympics, there was growing awareness that Brazil had not met the water quality goals outlined in their bid, and that athletes might be swimming, sailing, rowing or canoeing in waters contaminated with untreated human sewage. News articles discussed the poor water quality in competition waters, health risks to the athletes and the reasons why the US$ 4 billion pledged to greatly reduce the flow of untreated sewage into Guanabara Bay had not materialized.

A common theme of these articles was one of shock: that sewage was being disposed of untreated into the environment, that water quality was so poor and that elite athletes might risk their health to compete in the Olympics.

These articles are accurate: There is health risk to Olympics athletes, and having athletes compete in water contaminated with human sewage is reprehensible. In the next few days to weeks, we’ll learn what consequences there might be of this broken pledge.

However, what is missing from many, but not all, of the coverage is that the situation in Rio is not only not abnormal, it is common. Currently, about one-third of the global population (2.4 billion people) does not have access to sanitation facilities, such as a latrine or sewerage system, including 946 million people who have no facilities and practice open defecation. Another 2.1 billion urban residents worldwide use improved sanitation facilities that do not safely dispose of human waste, including 1.5 billion who use sewerage systems without treatment.

Rio’s water problems also highlight the limitations of reliance on centralized wastewater treatment systems. To meet the needs of the billions of people who suffer the health consequences of untreated human sewage every day, we need new technological innovations and approaches to sanitation provision.

Varying treatment around the world

Americans might be surprised to learn how recently current-day sewage treatment was introduced.

Today’s sewage treatment in the United States has its roots in engineering innovations from the late 19th and early 20th century. During this time, U.S. cities installed water systems that provided piped, treated and safe water supplies to households. This provision is credited with large reductions in infant and child deaths and elimination of epidemic diseases such as cholera and typhoid.

With the installation of these water supplies came the need for household wastewater disposal. Sewerage systems, where household wastewater is centrally collected and disposed, were first installed in the early 1900s. By 1940, half of the population with sewers also had some water treatment before disposal. In more rural areas, septic tanks were installed.

The Deer Island wastewater treatment plant was the centerpiece of a project to clean up the Boston Harbor. It wasn’t fully operational until 2000.
Doc Searls/flickr, CC BY

Over time, treatment and environmental disposal improved. The Boston Harbor, for instance, was once known as one of the dirtiest in the U.S. The centerpiece of the $3.8 billion cleanup project is the Deer Island wastewater treatment plant, which became fully operational in the year 2000, treats wastewater for over 2.5 million people, disposes of water 9.5 miles into the ocean instead of into Boston Harbor and vastly improved Boston Harbor water quality. In the year 2000, in North America, about 90 percent of wastewater was treated before disposal.

The United States’ situation, unfortunately, is not the norm.

In the year 2000, the percentage of urban wastewater collected through sewerage systems treated before disposal was only 66 percent for Europe, 35 percent for Asia, 14 percent for Latin America and the Caribbean, and less than one percent for Africa.

In Rio, only 12 percent of sewerage system wastewater was treated when the city was awarded the Olympics; that number is estimated to be 65 percent today. While this is an impressive improvement, it is short of the pledged 80 percent.

The health effects of exposure to human sewage are myriad, including diarrhea, the cause of 760,000 deaths in children per year worldwide, and stunting, which impacts 162 million children under five throughout the world. Due to these health consequences, in 2007, sanitation provision was voted the greatest medical advance since 1840 by readers of the prestigious British Medical Journal.

Technical and social innovation

But reversing these health threats will require that countries take a different path than that the U.S. took during the 20th century.

The primary challenge of improving the current worldwide sanitation situation is that the three existing sanitation solutions – sewerage systems, septic tanks, and latrines – have limitations.

Sewerage systems are expensive to install, and are fixed systems that lack the ability to rapidly expand with population growth; septic tanks require land with appropriate soils; and latrines require space, fill quickly and do not treat waste.

Because installing centralized sewage treatment plants is expensive and plants do not expand quickly to match population growth, alternative methods such as regular waste collection businesses are needed. gtzecosan/flickr, CC BY

Thus, there is need for new sanitation technologies that isolate human waste from the environment and provide options for the fastest-growing segment of the worldwide population: those living in densely populated mega-cities and urban slums. There is active and ongoing research and programming in developing alternative approaches and technologies, some examples of which include:

  • Community mobilization strategies using education to encourage communities to completely eliminate open defecation by triggering the communities’ desire for collective change. These programs can encourage local development of sanitation solutions, and certify communities as open-defecation free.
  • Systems-based approaches where sanitation facilities are built and franchised by local operators that charge a per-use fee or are installed in community institutions. Waste is collected and converted at a centralized facility to organic fertilizer, insect-based animal feed and renewable energy.
  • Social enterprise services where container-based toilets are installed in homes at no cost, and a monthly charge is assessed for waste collection. Waste is then transformed into briquettes and sold as a clean-burning alternative to charcoal.

While there are promising advances, many are currently small-scale, and more work is needed to reach the 2.5 billion without access to any improved sanitation facilities and additional 2.1 billion urban residents using improved sanitation facilities that do not safely dispose of human waste.

As the Rio Olympics proceed, and we hope for the health and safety of the elite athletes competing in contaminated waters, let us also consider – and work to improve sanitary conditions for – the billions of people worldwide who daily suffer the health consequences of living in an environment contaminated with human waste.

The ConversationDaniele Lantagne, Assistant Professor of Civil and Environmental Engineering, Tufts University

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

How Tiny Primate Virtual Brains Help with Understanding Evolution

Virtual brains reconstructed from ancient, kiwi-sized primate skulls could help resolve one of the most intriguing evolutionary mysteries: how modern primates developed such large brains.

Paleontologists found clues in the remarkably preserved skulls of adapiforms, lemur-like primates that scurried around the tropical forests of Wyoming about 50 million years ago. Thought to be a link between primitive and advanced primates, their fossil skulls are the best evidence available for understanding the neuroanatomy of the earliest ancestors of modern primates.

But there was just one problem—the brain cavities of the fragile skulls contained only rock and dust.

That is, until scientists used CT technology to create the first virtual 3D brain casts of the early primates. The eight virtually reconstructed and dissected brains—the most ever created for a single study—show an evolutionary burst including improved vision and more complex neurological function came before the brain size boost.

Tiny primate brain virtual "casts"
Top and bottom views, respectively, of the virtual brains of Notharctus tenebrosus (A, B, C, E and F), Adapis parisiensis (G and H), and Smilodectes gracilis (bottom two rows) within transparent renderings of their skulls. (Credit: U. Florida)

“It may be that these early specializations allowed primate brains to expand later in time,” says lead author Arianna Harrington, previously a undergraduate and master’s student at the Florida Museum of Natural History at the University of Florida, who is now a doctoral student at Duke University. “The idea is that any patterns we find in primate brain evolution could lead to a better understanding of the early evolution that led to the human brain.”

Scientists have long debated whether primates have always had big brains compared to body size, or if the trait appeared later. The new study’s findings, published in the Journal of Human Evolution, are consistent with previous endocast studies of Australopithecus afarensis, the oldest hominid known, andVictoriapithecus macinnesi, an early Old World monkey, which showed brain size increase followed brain specialization in early hominids and monkeys.

primate-brain

Adapiforms, which are not directly related to humans, evolved after the earliest primate ancestors, called plesiadapiforms, which lived about 65 million years ago. The scientists created virtual endocasts for three different species of adapiforms: Notharctus tenebrosus and Smilodectes gracilis from the middle Eocene Bridger formation of Wyoming and a late Eocene European specimen named Adapis parisiensis.

Adapiforms’ skulls differ from the earlier plesiadapiforms in a few ways including having more forward-facing eyes. The new virtual endocasts allowed scientists to take a closer look at anatomical features which revealed that, while adapiforms placed relatively less emphasis on smell more similar to modern primate brains, the relative brain size was not so different from that of plesiadapiforms, says study coauthor Jonathan Bloch, curator of vertebrate paleontology at the Florida Museum.

“While it’s true humans and other modern primates have very large brains, that story started down at the base of our group,” Bloch says. “As our study shows, the earliest primates actually had relatively small brains. So they didn’t start out with large brains and maintain them.”

Modern primates are specialized in the visual sense. One of the main differences between the early plesiadapiforms and adapiforms is the region of the brain responsible for the sense of smell, the olfactory bulb, is smaller, while there appears to be an expansion in the area of the brains responsible for vision, Harrington says.

“It is likely this indicates they’re beginning to rely more on vision than smell,” she says. “Scientists have hypothesized that vision may have helped early primates forage in complex arboreal forest systems.”

Source: Republished from Futurity.org as a derivative work under the Attribution 4.0 International license. Original article posted to Futurity by . 

Now, Check Out:

Ancient DNA in lake mud sheds light on the mystery of how humans first reached America

By Suzanne McGowan, University of Nottingham.

Modern humans started spreading from Africa to Europe, Asia and Australia some 100,000 years ago – a process that took about 70,000 years. We also know that at some point in the past 25,000 years, a group managed to reach America from Siberia at the end of the last ice age.

However, exactly when this occurred and which route these early pioneers took has long been debated. Now new research based on ancient DNA and plant remains from lake deposits, published in Nature, is finally helping us to answer these questions.

The study investigated a 1,500km long strip of land that was an “ice-free corridor: during the ice age, located in the British Colombia-Alberta region of Canada. For many years, scientists considered this region to be the only place where the two vast ice sheets which covered most of Canada during the last ice age did not meet. Theories of human migration therefore suggested that the earliest migrants from Siberia travelled across the Bering land bridge, exposed at that time due to lower sea levels, through Alaska, and down this open corridor, colonising North America after this time.

However, as new evidence has accumulated, scientists have started to question whether this is plausible. Radiocarbon dating, which is notoriously tricky to interpret, suggests that the ice sheets did in fact meet to make the corridor impassable for a period lasting from around 23,000 years ago until around 14-15,000 years ago. What’s more, new archaeological discoveries have revealed that the earliest human remains from America date back to 14,700 years ago – and they were discovered thousands of kilometres to the south in Chile. To get all the way to Chile by this time, these people must have arrived in the Americas much earlier – when it was impossible to pass through the ice.

The distribution of the early archaeological remains across North America also do not cluster around the ice-free corridor area, suggesting there was no progressive southward movement of humans.

Tracing ancient climate

The study looked at the past environmental conditions in the corridor. If it was indeed a migration pathway for humans, it must have supported the plants and animals that humans require to survive. Archaeological evidence from other areas show that early North Americans hunted large animals such as bison and mammoth, as well as fish and waterfowl during the later stages of the ice age.

Laminated lake sediments, younger layers deposited on top of older layers, containing molecular and fossil evidence revealing the succession of plants and animals in the ice-free corridor. Mikkel Winther Pedersen

Lake sediments can help shed light on the plant and animal life of this period because the successive layers of sediment allow us to step back in time to reveal a history of past environments. The researchers recovered sediment cores dating back to almost 13,000 years ago from an area of the corridor which is thought to be the last to become ice-free. Identification of the pollen grains and small fragments of plants in sediments are important in revealing vegetation development.

Lake sediments encapsulate a cocktail of partially decomposed compounds and organic remains, including DNA from the tissues and excretions of organisms – leaving a unique marker of their presence. As it gets older, the DNA breaks down into small fragments, increasing the challenge of isolating messages. The researchers used “shotgun sequencing” which screens the entire DNA cocktail to look for matches with known DNA databases.

These analyses show that around 12,900 years ago, a large lake covered this area, formed by glacial meltwaters. The surrounding vegetation was very sparse, comprising a few grasses and herbs. Around 12,700 years ago, steppe (known as prairie in North America) developed – with sagebrush, birch and willow. These enabled bison to roam the area by 12,600 years ago, followed by small mammals, mammoth, elk and bald eagles by 12,400 years ago.

The authors therefore argue that the corridor only became a viable passage for human travel around 12,700 years ago, meaning it couldn’t have been the first migration route into America. Instead, it became an alternative route slightly later on.

So where did the first humans enter the Americas? The currently favoured theory is that humans migrated via the Bering land bridge along the western Pacific coastline at a time when sea levels were lower, exposing an ice-free coastline for travel with the possibility for transport over water. The so-called “Kelp Highway Hypothesis” also suggests that marine resources were very abundant at this time, and easily capable of supporting migrant populations. Archaeologists have so far struggled to investigate this hypothesis thoroughly, however, because most remains are submerged under seas which are now around 120 metres higher than they were during the ice-age.

Map outlining the opening of the human migration routes in North America revealed by the results presented in this study.
Mikkel Winther Pedersen

The study has implications for later groups of Americans including the “Clovis people” who existed between 13,400-12,800 years ago. The new data suggests these people may not have had much use of the corridor either – the steppe didn’t develop until about 12,700 years ago. However, this is controversial because another very recent genetic analysis from bison in the area suggests these animals were roaming the corridor around 13,400 years ago – making it viable for humans.

The best way to tackle these conflicting strands of evidence would be to commission further studies incorporating palaeontology, archaeology and palaeoenvironmental work to resolve the question.

The ConversationSuzanne McGowan, Head of School of Geography (UNMC), University of Nottingham

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

 

Why you shouldn’t want to always be happy

By Frank T. McAndrew, Knox College.

In the 1990s, a psychologist named Martin Seligman led the positive psychology movement, which placed the study of human happiness squarely at the center of psychology research and theory. It continued a trend that began in the 1960s with humanistic and existential psychology, which emphasized the importance of reaching one’s innate potential and creating meaning in one’s life, respectively.

Since then, thousands of studies and hundreds of books have been published with the goal of increasing well-being and helping people lead more satisfying lives.

So why aren’t we happier? Why have self-reported measures of happiness stayed stagnant for over 40 years?

Perversely, such efforts to improve happiness could be a futile attempt to swim against the tide, as we may actually be programmed to be dissatisfied most of the time.

You can’t have it all

Part of the problem is that happiness isn’t just one thing.

Jennifer Hecht is a philosopher who studies the history of happiness. In her book “The Happiness Myth,” Hecht proposes that we all experience different types of happiness, but these aren’t necessarily complementary. Some types of happiness may even conflict with one another. In other words, having too much of one type of happiness may undermine our ability to have enough of the others – so it’s impossible for us to simultaneously have all types of happiness in great quantities.

For example, a satisfying life built on a successful career and a good marriage is something that unfolds over a long period of time. It takes a lot of work, and it often requires avoiding hedonistic pleasures like partying or going on spur-of-the-moment trips. It also means you can’t while away too much of your time spending one pleasant lazy day after another in the company of good friends.

On the other hand, keeping your nose to the grindstone demands that you cut back on many of life’s pleasures. Relaxing days and friendships may fall by the wayside.

As happiness in one area of life increases, it’ll often decline in another.

A rosy past, a future brimming with potential

This dilemma is further confounded by the way our brains process the experience of happiness.

By way of illustration, consider the following examples.

We’ve all started a sentence with the phrase “Won’t it be great when…” (I go to college, fall in love, have kids, etc.). Similarly, we often hear older people start sentences with this phrase “Wasn’t it great when…”

Think about how seldom you hear anyone say, “Isn’t this great, right now?”

Surely, our past and future aren’t always better than the present. Yet we continue to think that this is the case.

These are the bricks that wall off harsh reality from the part of our mind that thinks about past and future happiness. Entire religions have been constructed from them. Whether we’re talking about our ancestral Garden of Eden (when things were great!) or the promise of unfathomable future happiness in Heaven, Valhalla, Jannah or Vaikuntha, eternal happiness is always the carrot dangling from the end of the divine stick.

There’s evidence for why our brains operate this way; most of us possess something called the optimistic bias, which is the tendency to think that our future will be better than our present.

To demonstrate this phenomenon to my classes, at the beginning of a new term I’ll tell my students the average grade received by all students in my class over the past three years. I then ask them to anonymously report the grade that they expect to receive. The demonstration works like a charm: Without fail, the expected grades are far higher than one would reasonably expect, given the evidence at hand.

And yet, we believe.

Cognitive psychologists have also identified something called the Pollyanna Principle. It means that we process, rehearse and remember pleasant information from the past more than unpleasant information. (An exception to this occurs in depressed individuals who often fixate on past failures and disappointments.)

For most of us, however, the reason that the good old days seem so good is that we focus on the pleasant stuff and tend to forget the day-to-day unpleasantness.

Our memories of the past are often distorted, viewed through rose-colored glasses.
U.S. 97, South of Klamath Falls, Oregon, July 21, 1973. Chromogenic color print. © Stephen Shore.

Self-delusion as an evolutionary advantage?

These delusions about the past and the future could be an adaptive part of the human psyche, with innocent self-deceptions actually enabling us to keep striving. If our past is great and our future can be even better, then we can work our way out of the unpleasant – or at least, mundane – present.

All of this tells us something about the fleeting nature of happiness. Emotion researchers have long known about something called the hedonic treadmill. We work very hard to reach a goal, anticipating the happiness it will bring. Unfortunately, after a brief fix we quickly slide back to our baseline, ordinary way-of-being and start chasing the next thing we believe will almost certainly – and finally – make us happy.

My students absolutely hate hearing about this; they get bummed out when I imply that however happy they are right now – it’s probably about how happy they will be 20 years from now. (Next time, perhaps I will reassure them that in the future they’ll remember being very happy in college!)

Nevertheless, studies of lottery winners and other individuals at the top of their game – those who seem to have it all – regularly throw cold water on the dream that getting what we really want will change our lives and make us happier. These studies found that positive events like winning a million bucks and unfortunate events such as being paralyzed in an accident do not significantly affect an individual’s long-term level of happiness.

Assistant professors who dream of attaining tenure and lawyers who dream of making partner often find themselves wondering why they were in such a hurry. After finally publishing a book, it was depressing for me to realize how quickly my attitude went from “I’m a guy who wrote a book!” to “I’m a guy who’s only written one book.”

But this is how it should be, at least from an evolutionary perspective. Dissatisfaction with the present and dreams of the future are what keep us motivated, while warm fuzzy memories of the past reassure us that the feelings we seek can be had. In fact, perpetual bliss would completely undermine our will to accomplish anything at all; among our earliest ancestors, those who were perfectly content may have been left in the dust.

This shouldn’t be depressing; quite the contrary. Recognizing that happiness exists – and that it’s a delightful visitor that never overstays its welcome – may help us appreciate it more when it arrives.

Furthermore, understanding that it’s impossible to have happiness in all aspects of life can help you enjoy the happiness that has touched you.

Recognizing that no one “has it all” can cut down on the one thing psychologists know impedes happiness: envy.

The ConversationFrank T. McAndrew, Cornelia H. Dudley Professor of Psychology, Knox College

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

 

Brazil’s sewage woes reflect the growing global water quality crisis

By Joan Rose, Michigan State University.

All eyes are turned toward Rio de Janeiro to watch top athletes from all over the world compete. Yet the headlines continue to highlight the problems with the water quality and the risks to the athletes who swim, row and sail, and even to tourists simply visiting the beaches.

Large concentrations of disease-causing viruses have been found in the aquatic venues, particularly in the Rodrigo de Freitas Lagoon, where Olympic rowing will take place, and the Gloria Marina, the starting point for the sailing races. These viruses – adenoviruses, rotaviruses and noroviruses – are coming from human fecal wastes, untreated and/or inadequately treated sewage, and cause a variety of health problems, ranging from milder symptoms such as headache, respiratory infection or diarrhea to severe illness impacting the heart, liver and central nervous system.

But Brazil’s wastewater woes are hardly unique. The water quality of lakes, rivers and coastal shorelines around the world is degrading at an alarming rate. In fact, pollution of the 10 largest rivers on earth is so significant that it affects five billion people.

One of the root problems in Rio and other places is how water quality is tested. Monitoring for a broader set of viruses and other microbes in water would be a big step in improving public health.

Beyond e.coli testing

Human fecal waste remains one of the most important sources of pathogens. Today, water quality is most often measured by testing for E.coli bacteria, and this is the standard used around the world. But we have better ways to identify the microbes that cause problems when pollution, such as sewage, is released in our rivers, lakes and shorelines.

In my own research, my colleagues and I have tested for the presence of an alternative virus (known as the coliphage) as an inexpensive indicator for evaluating sewage treatment. We also use a whole variety of other tests which allow us to monitor for specific pathogens including viruses.

Our analysis and others suggest we should be striving at a minimum for 99.9 percent reduction of viruses by the variety of sewage treatment designs. If we rely on testing only for E.coli bacteria, we won’t be able to remove viruses.

Testing for a broader set of microbes makes it easier to diagnose what the source of pollutants are. For example, these microbial source tracking tools allow one to trace the pollution back to humans, cattle or pigs. We have used these tests throughout the U.S. and Europe, and they are now being used in resource-poor areas including Africa and South America. While these methods are not routine and are slightly more expensive, the results provide valuable information that allows one to better remediate water quality problems.

Studies on how frequently pathogens occur can then be connected back to the sources, with recommendations on treatment in order to reverse pollution trends. Incentives can be used to enhance best management practices such as preventing runoff from farms, composting to reduce pathogens in manure and improved disinfection of wastewater to kill off viruses.

Moving targets

Globally, the challenge of implementing new tests and treatments is immense. In the last 60 years we have seen a great acceleration of population growth, and this, in combination with lack of sewage treatment and failing infrastructure, has caused a continual degradation of water quality, as demonstrated by increasing toxic algal blooms and fecal contamination that cause microbial hazards. Indeed, one of the United Nations’ Development Goals is “access to improved sanitation facilities.”

In international rankings, Brazil went from 67 percent to 83 percent access (1990 to 2015) for access to sanitation. Yet progress varies geographically across the states in Brazil. While rural areas may have on-site water treatment systems and urban areas are collecting wastewater, government reports show only 14 percent to 46 percent of the sewage generated in Brazil is treated.

Around the world, the regulations governing water quality for recreation are in urgent need of revisions in part because of the growing array of pathogens in wastewater.

Millions of dollars were spent to clean up the trash and treat sewage in the waterways around Rio before the Olympics, but water quality remains a worry.
Ricardo Moraes/Reuters

Sewage contains well over 100 different viruses (adenoviruses, astroviruses, coxsackieviruses, enteroviruses, noroviruses and rotaviruses) among other pathogens like the enteric protozoa (Cryptosporidium). Newly emerging viruses such as Cycloviruses, which are causing neurological problems in children in Asia, are also showing up in sewage. Thus, the detection of these large concentrations of adenoviruses such as was found in Brazil is likely the tip of the iceberg.

It must be said clearly that the E.coli test simply does not work for viruses, and we must evaluate whether sewage treatment is properly removing viruses. While the World Health Organization, the U.S. EPA, the EU and the scientific community have known about the deficiencies of the E.coli indicator system for decades, little has been done to address this. Monitoring costs, lack of development of standard methods and no focus on a water diagnostic strategy are among the reasons for this lack of advancement.

Yet to my knowledge, many government agencies and even large nonprofits such as the Gates Foundation are not aware of these limitations. The E.coli approach alone cannot help resolve the questions that need to be answered to improve sanitation, sewage treatment and water reuse while protecting important aquatic ecosystem services.

Different paths of contact

New molecular tests can detect both live and dead viruses. Adenoviruses, for example, have been found in raw sewage around the world. If adequate treatment and disinfection are used, this contamination can be reduced to nondetectable levels.

The numbers of adenoviruses found in Rio were reported from 26 million to 1.8 billion per liter, which is essentially the level found in untreated sewage. It is not known how many viruses were alive but 90 percent of the samples did contain some level of live viruses.

Adenoviruses have been found in U.S. waters as well, posing a threat to public health. Our studies in Chicago found 65 percent of the Chicago Area Waterways System (CAWS) which receives treated wastewater tested positive for adenoviruses, with average concentrations of 2,600 viruses per liter in the canals and about 110 viruses per liter on the beaches. These data indicate some die-off as viruses move toward the beach, but some remain alive and would be able to cause disease. About 4 percent of the people using these waters for boating and fishing became sick. The presence of these viruses and the subsequent illnesses indicate the need for greater testing and treatment.

Around the world, those who swim in and boat on or use polluted surface waters for hygienic purposes such as bathing, cleaning clothes, washing dishes or even for religious purposes are all at risk of diarrhea, respiratory disease, skin, eye, ear and nose infections. This is the sad state of affairs and the reality for many people throughout the world. This does not even account for the risks associated with irrigation of food crops or use of the water for animals and drinking water.

While the spotlight is shining on the athletes over the next few weeks, let us also shine a spotlight on what we can do to improve and restore water quality around the world through our collective efforts, use of new tools and risk frameworks, moving the political will one step closer toward sewage treatment and protection of the biohealth of the blue planet.

The ConversationJoan Rose, Laboratory Director/Principal Investigator in Water Research, Michigan State University

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

Biohybrid robots built from living tissue start to take shape [Video]

By Victoria Webster, Case Western Reserve University.

Think of a traditional robot and you probably imagine something made from metal and plastic. Such “nuts-and-bolts” robots are made of hard materials. As robots take on more roles beyond the lab, such rigid systems can present safety risks to the people they interact with. For example, if an industrial robot swings into a person, there is the risk of bruises or bone damage.

Researchers are increasingly looking for solutions to make robots softer or more compliant – less like rigid machines, more like animals. With traditional actuators – such as motors – this can mean using air muscles or adding springs in parallel with motors. For example, on a Whegs robot, having a spring between a motor and the wheel leg (Wheg) means that if the robot runs into something (like a person), the spring absorbs some of the energy so the person isn’t hurt. The bumper on a Roomba vacuuming robot is another example; it’s spring-loaded so the Roomba doesn’t damage the things it bumps into.

But there’s a growing area of research that’s taking a different approach. By combining robotics with tissue engineering, we’re starting to build robots powered by living muscle tissue or cells. These devices can be stimulated electrically or with light to make the cells contract to bend their skeletons, causing the robot to swim or crawl. The resulting biobots can move around and are soft like animals. They’re safer around people and typically less harmful to the environment they work in than a traditional robot might be. And since, like animals, they need nutrients to power their muscles, not batteries, biohybrid robots tend to be lighter too.

Tissue-engineered biobots on titanium molds.
Karaghen Hudson and Sung-Jin Park, CC BY-ND

Building a biobot

Researchers fabricate biobots by growing living cells, usually from heart or skeletal muscle of rats or chickens, on scaffolds that are nontoxic to the cells. If the substrate is a polymer, the device created is a biohybrid robot – a hybrid between natural and human-made materials.

If you just place cells on a molded skeleton without any guidance, they wind up in random orientations. That means when researchers apply electricity to make them move, the cells’ contraction forces will be applied in all directions, making the device inefficient at best.

So to better harness the cells’ power, researchers turn to micropatterning. We stamp or print microscale lines on the skeleton made of substances that the cells prefer to attach to. These lines guide the cells so that as they grow, they align along the printed pattern. With the cells all lined up, researchers can direct how their contraction force is applied to the substrate. So rather than just a mess of firing cells, they can all work in unison to move a leg or fin of the device.

Tissue-engineered soft robotic ray that’s controlled with light.
Karaghen Hudson and Michael Rosnach, CC BY-ND

Biohybrid robots inspired by animals

Beyond a wide array of biohybrid robots, researchers have even created some completely organic robots using natural materials, like the collagen in skin, rather than polymers for the body of the device. Some can crawl or swim when stimulated by an electric field. Some take inspiration from medical tissue engineering techniques and use long rectangular arms (or cantilevers) to pull themselves forward.

Others have taken their cues from nature, creating biologically inspired biohybrids. For example, a group led by researchers at California Institute of Technology developed a biohybrid robot inspired by jellyfish. This device, which they call a medusoid, has arms arranged in a circle. Each arm is micropatterned with protein lines so that cells grow in patterns similar to the muscles in a living jellyfish. When the cells contract, the arms bend inwards, propelling the biohybrid robot forward in nutrient-rich liquid.

More recently, researchers have demonstrated how to steer their biohybrid creations. A group at Harvard used genetically modified heart cells to make a biologically inspired manta ray-shaped robot swim. The heart cells were altered to contract in response to specific frequencies of light – one side of the ray had cells that would respond to one frequency, the other side’s cells responded to another.

When the researchers shone light on the front of the robot, the cells there contracted and sent electrical signals to the cells further along the manta ray’s body. The contraction would propagate down the robot’s body, moving the device forward. The researchers could make the robot turn to the right or left by varying the frequency of the light they used. If they shone more light of the frequency the cells on one side would respond to, the contractions on that side of the manta ray would be stronger, allowing the researchers to steer the robot’s movement.

Toughening up the biobots

While exciting developments have been made in the field of biohybrid robotics, there’s still significant work to be done to get the devices out of the lab. Devices currently have limited lifespans and low force outputs, limiting their speed and ability to complete tasks. Robots made from mammalian or avian cells are very picky about their environmental conditions. For example, the ambient temperature must be near biological body temperature and the cells require regular feeding with nutrient-rich liquid. One possible remedy is to package the devices so that the muscle is protected from the external environment and constantly bathed in nutrients.

The sea slug Aplysia californica. Jeff Gill,  CC BY-ND

Another option is to use more robust cells as actuators. Here at Case Western Reserve University, we’ve recently begun to investigate this possibility by turning to the hardy marine sea slug Aplysia californica. Since A. californica lives in the intertidal region, it can experience big changes in temperature and environmental salinity over the course of a day. When the tide goes out, the sea slugs can get trapped in tide pools. As the sun beats down, water can evaporate and the temperature will rise. Conversely in the event of rain, the saltiness of the surrounding water can decrease. When the tide eventually comes in, the sea slugs are freed from the tidal pools. Sea slugs have evolved very hardy cells to endure this changeable habitat.

Sea turtle-inspired biohybrid robot, powered by muscle from the sea slug.
Dr. Andrew Horchler, CC BY-ND

We’ve been able to use Aplysia tissue to actuate a biohybrid robot, suggesting that we can manufacture tougher biobots using these resilient tissues. The devices are large enough to carry a small payload – approximately 1.5 inches long and one inch wide.

A further challenge in developing biobots is that currently the devices lack any sort of on-board control system. Instead, engineers control them via external electrical fields or light. In order to develop completely autonomous biohybrid devices, we’ll need controllers that interface directly with the muscle and provide sensory inputs to the biohybrid robot itself. One possibility is to use neurons or clusters of neurons called ganglia as organic controllers.

That’s another reason we’re excited about using Aplysia in our lab. This sea slug has been a model system for neurobiology research for decades. A great deal is already known about the relationships between its neural system and its muscles – opening the possibility that we could use its neurons as organic controllers that could tell the robot which way to move and help it perform tasks, such as finding toxins or following a light.

While the field is still in its infancy, researchers envision many intriguing applications for biohybrid robots. For example, our tiny devices using slug tissue could be released as swarms into water supplies or the ocean to seek out toxins or leaking pipes. Due to the biocompatibility of the devices, if they break down or are eaten by wildlife these environmental sensors theoretically wouldn’t pose the same threat to the environment traditional nuts-and-bolts robots would.

One day, devices could be fabricated from human cells and used for medical applications. Biobots could provide targeted drug delivery, clean up clots or serve as compliant actuatable stents. By using organic substrates rather than polymers, such stents could be used to strengthen weak blood vessels to prevent aneurysms – and over time the device would be remodeled and integrated into the body. Beyond the small-scale biohybrid robots currently being developed, ongoing research in tissue engineering, such as attempts to grow vascular systems, may open the possibility of growing large-scale robots actuated by muscle.

The ConversationVictoria Webster, Ph.D. Candidate in Mechanical and Aerospace Engineering, Case Western Reserve University

This article was originally published on The Conversation. Read the original article.

Now, Check Out:

[Video] IRIS Captures Plasma Rain on the Sun’s Surface

On July 24, 2016, NASA’s Interface Region Imaging Spectrograph, or IRIS, captured a mid-level solar flare: a sudden flash of bright light on the solar limb – the horizon of the sun – as seen at the beginning of this video. Solar flares are powerful explosions of radiation. During flares, a large amount of magnetic energy is released, heating the sun’s atmosphere and releasing energized particles out into space. Observing flares such as this helps the IRIS mission study how solar material and energy move throughout the sun’s lower atmosphere, so we can better understand what drives the constant changes we can see on our sun.

As the video continues, solar material cascades down to the solar surface in great loops, a flare-driven event called post-flare loops or coronal rain. This material is plasma, a gas in which positively and negatively charged particles have separated, forming a superhot mix that follows paths guided by complex magnetic forces in the sun’s atmosphere. As the plasma falls down, it rapidly cools – from millions down to a few tens of thousands of kelvins. The corona is much hotter than the sun’s surface; the details of how this happens is a mystery that scientists continue to puzzle out. Bright pixels that appear at the end of the video aren’t caused by the solar flare, but occur when high-energy particles bombard IRIS’s charge-coupled device camera – an instrument used to detect photons.

Source: Republished from NASA.gov under public domain rights and in accordance with the NASA Multimedia Guidelines. 

Now, Check Out

Sex on TV: Less impact on teens than you might think

By Christopher Ferguson, Stetson University .

Few people would doubt that sex is ubiquitous in media – whether movies, television, music or books – and that teens today have unprecedented access to all of it. It’s often taken for granted that this easy access to “sexy media” has an influence on teenage sexuality.

Specifically, the worry is that teens may have sex earlier or engage in higher-risk sexual activities such as having multiple partners or exposing themselves to potential pregnancies or STDs. In 2010 the American Academy of Pediatrics even published a position paper claiming that sexually explicit media could promote risky teen sexual behavior.

But government data find that teens are actually waiting longer than in the past to have sex. And teen pregnancy rates are at historic lows. How is it possible that sexy media has such a pernicious effect even as teen sexuality is becoming healthier?

I’ve spent more than a decade researching how media – like video games or advertising – influences youth behavior. What fascinates me is how society interacts with media, often embracing salacious content while simultaneously blaming it for societal problems, whether real or imagined.

So my colleagues and I decided to look at the research on sexy media and teenage sexual behavior to see how the strong the link between the two is.

Sexy media doesn’t predict sexual behavior

Despite the common assumptions about sex in the media and its alleged effects on teens, the evidence behind the link is weak. Some studies find evidence for a small effect (perhaps in some circumstances but not others), while others find no evidence for any effect.

One reason the evidence may not be conclusive is that there are practical and ethical limitations to conducting research. We can’t run experiments where teens watch different TV shows and we wait around to see who has sex. This means research often relies on self-reported data. What we do is ask teens to report on their sexual behavior and their media preferences, as well as other variables we might like to control for (such as personality or family environment) and see if correlations exist.

With this in mind, my colleagues Patrick Markey at Villanova and Danish researcher Rune Nielsen and I conducted a meta-analysis of 22 studies with over 22,000 participants that examine the correlation between sexy media and teenage sexual behavior. A meta-analysis lets us look for commonalities in the results, and is something that had not been done previously with this pool of research.

All of the studies in the meta-analysis looked at depictions of sexual situations, nudity, partial nudity or explicit discussions of sex in television shows or movies easily accessible to minors (and thus excluded pornography).

In particular, we were curious to see whether sexy media predicted teen sexual behavior once other variables had been controlled. For instance, maybe boys tend to watch sexier media and also are more sexually risk-taking. Or perhaps youth who are more liberal in terms of personality are more open both to sexy media and earlier sexual initiation. Perhaps a difficult family background is the underlying key to understanding any correlation between media use habits and actual sexual behavior.

Ultimately, this is what we found. Once other factors such as family environment, personality or even gender were controlled, sexy media exposure did not meaningfully correlate with teen sexual behavior.

Contrary to common fears, sexy media doesn’t seem to have any practical significance for when teens first have sex or start other sexual behaviors. This lack of correlation is a warning sign we might be on the wrong track in trying to blame media for teen sexual risk-taking.

The kids are all right.
Group of teens via www.shutterstock.com.

Why doesn’t media influence teens?

There are numerous theories that discuss how individuals and media interact. However, many older media effects theories didn’t consider why people were drawn to media, how they processed it, or what they hoped to get from it. Such theories assumed viewers simply irrationally and purposelessly imitated what they saw. Most of the papers we examined in our meta-analysis were tests of these basic, automatic, media effects theories.

In the past few years, some scholars (myself included) have specifically called for the retirement of these older media effects theories. This is because the evidence increasingly suggests that fictional media such as feature movies or sitcoms media is too remote to have a clear impact on consumers’ behavior, especially compared to families and peers.

In addition, emerging evidence suggests that young children process fictional media differently from real events. If small children are able to process a difference between fictional events and real events, we can assume that teens don’t really expect media to reflect reality.

Our results regarding the limited impact of media also fit with the observations from societal data. Despite a plethora of sexual media available to teens, a crisis of risky teen sexual behavior has not emerged.

We watch what we’re interested in watching

Newer models of media use suggest that it is the individuals who consume media, not the media itself, who are the driving agents of behavior. Evidence suggests that users seek out and interpret media according to what they want to get from it, rather than passively imitating it.

People don’t generally accidentally watch media, sexual or otherwise, but are motivated to do so because of preexisting desires.

For instance, some recent studies have indicated that youth seek out media that fit with preexisting motives, called a selection effect, but that media don’t necessarily lead to further problem behaviors. For example, research suggests that some teens who are already aggressive might be interested in violent video games, but playing such games doesn’t make kids more aggressive.

That’s a point that sometimes seems ignored when we talk about teens and sex. Interest in sex is a largely biologically motivated process; fictional media really isn’t required. Teens will become interested in sex all on their own.

Parents have more influence than the media

Parents can rest a bit easier since the evidence suggests that media isn’t a primary driver of teen sexuality.

To the extent media has any impact at all, it is likely only in a vacuum left by adults reluctant to talk to kids about sex, especially the stuff kids really want to know.

How do you ask someone out on a date and how do you handle it if they say no? What does sex feel like? When is it OK to have sex? What are the risks and how do you avoid them? In the face of patient, empathic and informative discussions about sex by adults kids trust, the media likely has little influence.

Ultimately, whether media have salacious or more conscientious portrayals of sexuality, we should not expect media to replace conversations with youth by parents, guardians and educators.

I’m not suggesting everyone run out and buy “50 Shades of Grey” for their teen, but if teens happen to come across it (and they will), it’s not the end of the world.

The important thing for parents is to talk to their kids.

The ConversationChristopher Ferguson, Associate Professor of Psychology, Stetson University

This article was originally published on The Conversation. Read the original article.

Now, Check Out: