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Climate and Country WealthWhy are some countries stupendously rich and others horrendously poor? Social theorists have been captivated by this question since the late 18th century, when Scottish economist Adam Smith argued in his magisterial work The Wealth of Nations that the best prescription for prosperity is a free-market economy in which the government allows businesses substantial freedom to pursue profits. Smith, however, made a second notable hypothesis: that the physical geography of a region can influence its economic performance. He contended that the economies of coastal regions, with their easy access to sea trade, usually outperform the economies of inland areas.Coastal regions and those near navigable waterways are indeed far richer and more densely settled than interior regions, just as Smith predicted. Moreover, an area's climate can also affect its economic development. Nations in tropical climate zones generally face higher rates of infectious disease and lower agricultural productivity (especially for staple foods) than do nations in temperate zones. Similar burdens apply to the desert zones. The very poorest regions in the world are those saddled with both handicaps: distance from sea trade and a tropical or desert ecology. The basic lessons of geography are worth repeating, because most economists have ignored them. In the past decade the vast majority of papers on economic development have neglected even the most obvious geographical realities.The best single indicator of prosperity is gross national product (GNP) per capita – the total value of a country's economic output, divided by its population. A map showingthe world distribution of GNP per capita immediately reveals the vast gap between rich and poor nations. The great majority of the poorest countries lie in thegeographical tropics. In contrast, most of the richest countries lie in the temperate zones. Among the 28 economies categorized as high income by the World Bank, onlyHong Kong, Singapore and part of T aiwan are in the tropical zone, representing amere 2 percent of the combined population of the high-income regions. Almost all the temperate-zone countries have either high-income economies (as in the cases of North America, western Europe, Korea and Japan) or middle-income economies (as in thecases of eastern Europe, the former Soviet Union and China). In addition, there is a strong temperate-tropical divide within countries that straddle both types of climates. Most of Brazil, for example, lies within the tropical zone, but the richest part of the nation – the southernmost states –is in the temperate zone.There are two major ways in which a region’s climate affects economic development. First, it affects the prevalence of disease. Many kinds of infectious diseases areendemic to the tropical and subtropical zones. This tends to be true of diseases inwhich the pathogen spends part of its life cycle outside the human host: for instance, malaria (carried by mosquitoes) and helminthic infections (caused by parasiticworms). Although epidemics of malaria have occurred sporadically as far north asBoston in the past century, the disease has never gained a lasting foothold in the temperate zones, because the cold winters naturally control the mosquito-basedtransmission of the disease. Winter could thus be considered the world's mosteffective public health intervention. It is much more difficult to control malaria intropical regions, where transmission takes place year-round and affects a large part of the population.According to the World Health Organization, 300 million to 500 million new cases of malaria occur every year, almost entirely concentrated in the tropics. Widespreadillness and early deaths obviously hold back a nation's economic performance by significantly reducing worker productivity. But there are also long-term effects that may be amplified over time through various social feedbacks. A high incidence of disease can alter the age structure of a country's population. Societies with high levelsof child mortality tend to have high levels of fertility: mothers bear many children to guarantee that at least some will survive to adulthood. Young children will therefore constitute a large proportion of that country's population. With so many children, poor families cannot invest much in each child's education. High fertility also constrains the role of women in society, because child rearing takes up so much of their adult lives.Moreover, temperature affects agricultural productivity. Of the major food grains – wheat, maize and rice – wheat grows only in temperate climates, and maize and rice crops are generally more productive in temperate and subtropical climates than intropical zones. On average, a hectare of land in the tropics yields 2.3 metric tons of maize, whereas a hectare in the temperate zone yields 6.4 tons. Farming in tropical rain-forest environments is hampered by the fragility of the soil: high temperatures mineralize the organic materials, and the intense rainfall leaches them out of the soil. In tropical environments that have wet and dry seasons–such as the Africansavanna–farmers must contend with the rapid loss of soil moisture resulting from high temperatures, the great variability of precipitation, and the ever present risk of drought. Moreover, tropical environments are plagued with diverse infestations of pests and parasites that can devastate both crops and livestock.Moderate advantages or disadvantages in geography can lead to big differences inlong-term economic performance. Favorable agricultural or health conditions mayboost per capita income in temperate-zone nations and hence increase the size of their economies. The resulting inventions further raise economic output, spurring yet more inventive activity. The moderate geographical advantage is thus amplified through innovation. In contrast, the low food output per farm worker in tropical regions tends to diminish the size of cities. With a smaller proportion of the population in urbanareas, the rate of technological advance is usually slower. The tropical regionstherefore remain more rural than the temperate regions, with most of their economic activityconcentrated in low-technology agriculture rather than in high-technologymanufacturing and services.Geographical factors, however, are only part of the story. Social and economic institutions are critical to long-term economic performance. It is particularly instructive to compare the post-World War II performance of socialist and free-market economies in neighboring countries that share the same geographical characteristics: North and South Korea, East and West Germany, the Czech Republic and Austria, and Estonia and Finland. In each case we find that free-marketinstitutions vastly outperformed their counterparts.If these findings are true, the policy implications are significant. Aid programs for developing countries will have to be revamped to specifically address the problems imposed by climate and geography. In particular, new strategies have to be formulated that would help nations in tropical zones raise their agricultural productivity and reduce the prevalence of diseases such as malaria.YawnWhile fatigue, drowsiness or boredom easily bring on yawns, scientists are discovering there's more to yawning than most people think. Not much is known about why we yawn or if it serves any useful function, and very little research has been done on the subject. However, there are several theories about why we yawn. Here are the four most common:The physiological theory: Our bodies induce yawning to draw in more oxygen or remove a buildup of carbon dioxide. This theory helps explain why we yawn in groups. Larger groups produce more carbon dioxide, which means our bodies would act to draw in more oxygen and get rid of the excess carbon dioxide. However, if our bodies make us yawn to draw in needed oxygen, wouldn't we yawn during exercise? Robert Provine, a developmental neuroscientist at the University of Maryland, Baltimore County and a leading expert on yawning, has tested this theory: Giving people additional oxygen didn't decrease yawning, and decreasing theamount of carbon dioxide in a subject's environment also didn't prevent yawning.The evolution theory: Some think that yawning began with our ancestors, who used yawning to show their teeth and intimidate others. An offshoot of this theory is the idea that yawning developed from early man as a signal for us to change activities. Another speculated reason for yawning is the desire to stretch one's muscles. Yawns are often accompanied by the urge to stretch. Prey animals must be ready to physically exert themselves at any given moment. There have been studies that suggest yawning, especially psychological "contagious" yawning, may have developed as a way of keeping a group of animals alert. If an animal is drowsy or bored, it may not be as alert as it should to be prepared to spring into action. Therefore, the "contagious" yawn could be an instinctual reaction to a signal from one member of the "herd" reminding the others to stay alert. Nervousness has also been suggested as a possible reason. Nervousness often indicates the perception of an impending need for action. Anecdotal evidence suggests that yawning helps increase the state of alertness of a person. Paratroopers have been noted to yawn in the moments before they exit the aircraft.The brain-cooling theory: A more recent theory proposed by researchers is that since people yawn more in situations where their brains are likely to be warmer -- tested by having some subjects breathe through their noses or press hot or cold packs to their foreheads -- it's a way to cool down their brains. In 2007, researchers, including a professor of psychology, from the University of Albany proposed that yawning may be a means to keep the brain cool. Mammalian brains operate best within a narrow temperature range. In two experiments, they demonstrated that both subjects with cold packs attached to their foreheads and subjects asked to breathe strictly nasally exhibited reduced contagious yawning when watching videos of people yawning.A similar recent hypothesis is that yawning is used for regulation of body temperature. Similarly, a study by Jared Guttmann at Worcester Polytechnic Institute found that when a subject wearing earplugs yawned, a breeze is heard caused by the flux of the air moving between the subject's ear and the environment. Researcher Guttmann determined that ayawn causes one of three possible situations to occur: the brain cools down due to an influx or outflux of oxygen, the pressure in the brain is reduced by an outflux of oxygen, or the pressure of the brain is increased by an influx of air caused by increased cranial space. What does it matter if our brains are cold or hot? Cool brains can think more clearly; hence, yawning might have developed to keep us alert.Interestingly, while all vertebrates (including fish) yawn, only humans, chimps and possibly dogs find yawns contagious. And people don't find them contagious until they're about 4 years old. Recent studies show contagious yawning may be linked to one's capacity for empathy. In one study, autistic and non-autistic children were shown videos of people yawning and people simply moving their mouths. Both groups of kids yawned the same amount when viewing the video of people moving their mouths. But the non-autistic kids yawned much more frequently than those with autism when watching people really yawning.Since autism is a disorder that affects a person's social interaction skills, including the ability to empathize with others, the autistic kids' lack of yawning when watching others do so could indicate they're less empathetic. The study also found the more severe a child's autism, the less likely he or she was to yawn. On a positive note, someday doctors may be able to diagnose cognitive disabilities in young children more easily by seeing whether or not they can catch a yawn from other.So even though we still don't know for sure why we yawn, we do know lots of interesting things about yawning: you start yawning in utero; you yawn when you're aroused; more than half of you will yawn if you see someone else yawn; and reading about yawning makes you yawn.The soviet calendarThere are no fortresses that Bolsheviks cannot storm’. With these words, Stalin expressed the dynamic self-confidence of the Soviet Union’s Five Year Plan: weak and backward Russia was to turn overnight into a powerful modern industrial country. Unlimited enthusiasm was the mood of the day, with the Communists believing that iron will and hard-working manpower alone would bring about a new world. Enthusiasm spread to Time itself, in the desire to make the state a huge efficient machine, where not a moment would be wasted, especially in the workplace. Lenin had already been intrigued by the ideas of the American Frederick Winslow T aylor (1856-1915), whose time-motion studies had discovered ways of stream-lining effort so that every worker could produce the maximum. The Bolsheviks were also great admirers of Henry Ford’s assembly line mass production and of his Fordson tractors that were imported by the thousands. The engineers who came with them to train their users helped spread what became a real cult of Ford. Emulating and surpassing such capitalist models formed part ofthe training of the new Soviet Man, a heroic figure whose unlimited capacity for work would benefit everyone in the dynamic new society. All this culminated in the Plan, which has been characterized as the triumph of the machine, where workers would become supremely efficient robot-like creatures.Yet this was Communism whose goals had always included improving the lives of the proletariat. One major step in that direction was the sudden announcement in 1927 that reduced the working day from eight to seven hours. In January 1929, all industries were ordered adopt the shorter day by the end of the Plan. Workers were also to have an extra hour off on the eve of Sundays and holidays. Typically though, the state took away more than it gave, for this was part of a scheme to increase production by establishing a three-shift system. That meant that the factories were open day and night and that many had to work at highly undesirable hours.Hardly had that policy been announced, though, than Yuri Larin, who had been a close associate of Lenin and architect of his radical economic policy, came up with an idea for even greater efficiency. Workers were free and plants were closed on Sundays. Why not abolish that wasted day by instituting a continuous work week so that the machines could operate to their full capacity every day of the week? When Larin presented his idea to the Congress of Soviets in May 1929, no one paid much attention. Soon after, though, he got the ear of Stalin, who approved. Suddenly, in June, the Soviet press was filled with articles praising the new scheme. In August, the Council of Peoples’ Commissars ordered the continuous work week brought into immediate effect, during the height of enthusiasm for the Plan, whose goals the new schedule seemed guaranteed to forward.The idea seemed simple enough, but turned out to be very complicated in practice. Obviously, the workers couldn’t be made to work seven days a week, nor should their total work hours be increased. The solution was ingenious: a new five-day week would have the workers on the job for four days, with the fifth day free; holidays would be reduced from ten to five, and the extra hour off on the eve of rest days would be abolished. Staggering the rest-days between groups of workers meant that each worker would spend the same number of hourson the job, but the factories would be working a full 360 days a year instead of 300. The 360 divided neatly into 72 five-day weeks. Workers in each establishment (at first factories, then stores and offices) were divided into five groups, each assigned a colour which appeared on the new Uninterrupted Work Week calendars distributed all over the country. Colour-coding was a valuable mnemonic device, since workers might have trouble remembering what their day off was going to be, for it would change every week. A glance at the colour on the calendar would reveal the free day, and allow workers to plan their activities.Official propaganda touted the material and cultural benefits of the new scheme. Workers would get more rest; production and employment would increase (for more workers would be needed to keep the factories running continuously); the standard of living would improve. Leisure time would be more rationally employed, for cultural activities (theatre, clubs, sports) would no longer have to be crammed into a weekend, but could flourish every day, with their facilities far less crowded. Shopping would be easier for the same reasons. Ignorance andsuperstition, as represented by organized religion, would suffer a mortal blow, since 80 per cent of the workers would be on the job on any given Sunday. The only objection concerned the family, where normally more than one member was working: well, the Soviets insisted, the narrow family was far less important than the vast common good and beside, arrangements could be made for husband and wife to share a common schedule.The continuous work week, hailed as a Utopia where Time itself was conquered and the sluggish Sunday abolished forever, spread like an epidemic. According to official figures 63 per cent of industrial workers were so employed by April 1930; in June, all industry was ordered to convert during the next year. The fad reached its peak in October when it affected 73 per cent of workers. In fact, many managers simply claimed that their factories had gone over to the new week, without actually applying it. Conforming to the demands of the Plan was important; practical matters could wait. By then, though, problems were becoming obvious. Most serious (though never officially admitted), the workers hated it. Coordination of family schedules was virtually impossible and usually ignored, so husbands and wives only saw each other before or after work; rest days were empty without any loved ones to share them - even friends were likely to be on a different schedule. Confusion reigned: the new plan was introduced haphazardly, with some factories operating five-, six- and seven-day weeks at the same time, and the workers often not getting their rest days at all.The soviet government might not have ignored all that depending on public approval, but the new week was far from having the vaunted effect on production. With the complicated rotation system, the work teams necessarily found themselves doing different kinds of work in successive weeks. Machines, no longer consistently in the hands of people who knew how to tend them, were often poorly maintained or even broken. As a result, the new week started to lose ground. Stalin’s speech in June 1931, which criticized the “depersonalized labor” its too hasty application had brought, marked the beginning of the end. In November, the government ordered the widespread adoption of the six-day week, which had its own calendar, with regular breaks on the 6th, 12th, 18th, 24th, and 30th, with Sunday usually as a working day. By July 1935 only 26 per cent of workers still followed the continuous schedule, and the six-day week was soon on its way out. Finally, in 1940, as part of the generalreversion to more traditional methods, both the continuous five-day week and the novel six-day week were abandoned, and Sunday returned as the universal day of rest. A bold but typically ill-conceived experiment was at an end.Ants and brain's neuronsAn individual ant is not very bright, but ants in a colony, operating as a collective, do remarkable things. A single neuron in the human brain can respond only to what the neurons connected to it are doing, but all of them together can be Immanuel Kant. That resemblance is why Deborah M. Gordon, StanfordUniversity assistant professor of biological sciences, studies ants. "I'm interested in the kind of system where simple units together do behave in complicated ways," she said.No one gives orders in an ant colony, yet each ant decides what to do next. For instance, an ant may have several job descriptions. When the colony discovers a new source of food, an ant doing housekeeping duty may suddenly become a forager. Or if the colony's territory size expands or contracts, patroller ants change the shape of their reconnaissance pattern to conform to the new realities. Since no one is in charge of an ant colony - including the misnamed "queen," which is simply a breeder - how does each ant decide what to do?This kind of undirected behavior is not unique to ants, Gordon said. How do birds flying in a flock know when to make a collective right turn? All anchovies and other schooling fish seem to turn in unison, yet no one fish is the leader. Gordon studies harvester ants in Arizona and, both in the field and in her lab, the so-called Argentine ants that are ubiquitous to coastal California. Argentine ants came to Louisiana in a sugar shipment in 1908. They were driven out of the Gulf states by the fire ant and invaded California, where they have displaced most of the native ant species. One of the things Gordon is studying is how they did so. No one has ever seen an ant war involving the Argentine species and the native species, so it's not clear whether they are quietly aggressive or just find ways of taking over food resources and territory.The Argentine ants in her lab also are being studied to help her understand how they change behavior as the size of the space they are exploring varies. "The ants are good at finding new places to live in and good at finding food," Gordon said. "We're interested in finding out how they do it." Her ants are confined by Plexiglas walls and a nasty glue-like substance along the tops of the boards that keeps the ants inside. She moves the walls in and out to change the arena and videotapes the ants' movements. A computer tracks each ant from its image on the tape and reads its position so she has a diagram of the ants' activities.The motions of the ants confirm the existence of a collective. "A colony is analogous to a brain where there are lots of neurons, each of which can only do something very simple, but together the whole brain can think. None of the neurons can think ant, but the brain can think ant, though nothing in the brain told that neuron to think ant." For instance, ants scout for food in a precise pattern. What happens when that pattern no longer fits the circumstances, such as when Gordon moves the walls? "Ants communicate by chemicals," she said. "That's how they mostly perceive the world; they don't see very well. They use their antennae to smell.So to smell something, they have to get very close to it. "The best possible way for ants tofind everything - if you think of the colony as an individual that is trying to do this - is to have an ant everywhere all the time, because if it doesn't happen close to an ant, they're not going to know about it. Of course, there are not enough ants in the colony to do that, so somehow the ants have to move around in a pattern that allows them to cover space efficiently."Keeping in mind that no one is in charge of a colony and that there is no central plan, how do the ants adjust their reconnaissance if their territory expands or shrinks? "No ant told them, 'OK, guys, if the arena is 20 by 20. . . .' Somehow there has to be some rule that individual ants use in deciding to change the shape of their paths so they cover the areas effectively. I think that that rule is the rate in which they bump into each other." The more crowded they are, the more often each ant will bump into another ant. If the area of their territory is expanded, the frequency of contact decreases. Perhaps, Gordon thinks, each ant has a threshold for normality and adjusts its path shape depending on how often the number of encounters exceeds or falls short of that threshold.If the territory shrinks, the number of contacts increases and the ant alters its search pattern. If it expands, contact decreases and it alters the pattern a different way. In the Arizona harvester ants, Gordon studies tasks besides patrolling. Each ant has a job. "I divide the tasks into four: foraging, nest maintenance, midden [piling refuse, including husks of seeds] and patrolling - patrollers are the ones that come out first in the morning and look for food. The foragers go where the patrollers find food. "The colony has about eight different foraging paths. Every day it uses several of them. The patrollers go out first on the trails and they attract each other when they find food. By the end of an hour's patrolling, most patrollers are on just a few trails. All the foragers have to do is go where there are the most patrollers."Each ant has its prescribed task, but the ants can switch tasks if the collective needs it. An ant on housekeeping duty will decide to forage. No one told it to do so and Gordon and other entomologists don't know how that happens. "No ant can possibly know how much food everybody is collecting, how many foragers are needed," she said. "An ant has to have very simple rules that tell it, 'OK, switch and start foraging.' But an ant can't assess globally how much food the colony needs. "I've done perturbation experiments in which I marked ants according to what task they're doing on a given day. The ants that were foraging for food were green, those that were cleaning the nest were blue and so on. Then I created some new situation in the environment; for example, I create a mess that the nest maintenance workers have to clean up or I'll put out extra food that attracts more foragers. "It turns out that ants that were marked doing a certain task one day switch to do a different task when conditions change." Of about 8,000 species of ants, only about 10 percent have been studied thus far. "It's hard to generalize anything about the behavior of ants," Gordon said. "Most of what we know about ants is true of a very, very small number of species compared to the number of species out there."Facial expressionA facial expression is one or more motions or positions of the muscles in the skin. These movements convey the emotional state of the individual to observers. Facial expressions are a form of nonverbal communication. They are a primary means of conveying social information among humans, but also occur in most other mammals and some other animal species.Fical expressions and their significance in the perceiver can, to some extent, vary between cultures.Humans can adopt a facial expression to read as a voluntary action. However, because expressions are closely tied to emotion, they are more often involuntary. It can be nearly impossible to avoid expressions for certain emotions, even when it would be strongly desirable to do so; a person who is trying to avoid insulting an individual he or she finds highly unattractive might nevertheless show a brief expression of disgust before being able to reassume a neutral expression. Microexpressions are one example of this phenomenon. The close link between emotion and expression can also work in the other direction; it has been observed that voluntarily assuming an expression can actually cause the associated emotion.Some expressions can be accurately interpreted even between members of different species- anger and extreme contentment being the primary examples. Others, however, are difficult to interpret even in familiar individuals. For instance, disgust and fear can be tough to tell apart.Because faces have only a limited range of movement, expressions rely upon fairly minuscule differences in the proportion and relative position of facial features, and reading them requires considerable sensitivity to same. Some faces are often falsely read as expressing some emotion, even when they are neutral, because their proportions naturally resemble those another face would temporarily assume when emoting. Also, a person's eyes reveal much about how they are feeling, or what they are thinking. Blink rate can reveal how nervous or at ease a person may be. Research by Boston College professor Joe Tecce suggests that stress levels are revealed by blink rates. He supports his data with statistics on the relation between the blink rates of presidential candidates and their success in their races. Tecce claims that the faster blinker in the presidential debates has lost every election since 1980. Though Tecce's data is interesting, it is important to recognize that non-verbal communication is multi-channeled, and focusing on only one aspect is reckless. Nervousness can also be measured by examining each candidates' perspiration, eye contact and stiffness.As Charles Darwin noted in his book The Expression of the Emotions in Man and Animals:the young and the old people of widely different races, both with man and animals, express the same state of mind by the same movements. Still, up to the mid-20th century most anthropologists believed that facial expressions were entirely learned and could therefore differ among cultures. Studies conducted in the 1960s by Paul Ekman eventually supported Darwin's belief to a large degree.。