The Co evolution of Genes and Culture
What is culture? Is it created by the genes, or superimposed upon human behavior from the "outside" as a new environment within which the genes must adapt and with which the genes have no "experience"? Or is culture something in between?Let's begin with an 1896 assessment by H. G. Wells of what culture is and why it is so important to the Human future.
"...it appears to me impossible to believe that man has undergone anything but an infinitesimal alteration in his intrinsic nature since the age of the unpolished stone. ... A decent citizen is always controlling and disciplining the impulses... ...it is indisputable that civilized man is in some manner different ... But that difference ... is in no degree inherited. ... With true articulate speech came the possibilities of more complex co‑operations... Came writing, and therewith a tremendous acceleration in the expansion of that body of knowledge and ideals which is the reality of the civilized state. ...in civilized man we have (1) an inherited factor, the natural man, who is the product of natural selection, the culminating ape, and a type of animal more obstinately unchangeable than any other living creature; and (2) an acquired factor, the artificial man, the highly plastic creature of tradition, suggestion, and reasoned thought. ...in a rude and undisciplined way indeed, ...humanity is even now consciously steering itself against the currents and winds of the universe in which it finds itself. In the future, it is at least conceivable, that men with a trained reason and a sounder science, both of matter and psychology, may conduct this operation far more intelligently, unanimously, and effectively, and work towards, and at last attain and preserve, a social organization so cunningly balanced against exterior necessities on the one hand, and the artificial factor in the individual on the other, that the life of every human being ... may be generally happy. To me, at least, this is no dream, but a possibility to be lost or won by men, as they may have or may not have the greatness of heart to consciously shape their moral conceptions and their lives to such an end." H. G. Wells, "Human Evolution, An Artificial Process," Fortnightly Review, Oct, 1896.
Wells viewed human nature as unchanging during our acquisition of a changeable culture. He leaves unaddressed whether or not he thought cultural changes were influenced by the genes (which hadn’t been generally recognized in 1896), but he doesn't believe that culture changed our inherited nature (our genotype).
Charles J. Lumsden and Edward O. Wilson, in their book Genes, Mind and Culture (1981), take the position that the evolution of culturgens causes evolutionary change in the genome, which in turn allows new directions for culture, etc. Each affects the other, and together they co‑evolve, reaching the elaborate cultural level of today's modern world. Their book is excessively mathematical, and can discourage all but the most accomplished mathematician; however, it is not necessary that one follow the rigorous mathematical treatments in the book to comprehend the concepts presented. I agree with their argument, and will present a synopsis of it here.It is easy to understand that cultural evolution is channeled by what is "possible." As a trivial example, consider a hypothetical cultural element, or "culturgen," forbidding the drinking of liquids. Any person fool enough to adhere to this regimen would die (unless sufficient liquids were present in the solid diet). Not only would practitioners not live long enough to spread the culturgen, but the need for liquids is so strongly rooted in our genes that the weird culturgen would lack appeal and fail to win converts.
A pork taboo, on the other hand, would face less resistance, and indeed has appeared at a location and time when eating pork was probably too risky to be worth its nutritional benefit. Thus, the genes "allow" some culturgens but not others.The incest taboo is a well‑studied culturgen, and it is found in all societies. Genes have evolved that identify incest situations and produce an aversion to their completion (in order to prevent the homozygotic expression of recessive genetic defects in offspring). The incest taboo is present in all human societies as well as many species. When it appears in animals that we normally do not believe are capable of culture, the behavior can be said to be hard‑wired. It is not strongly hard‑wired in humans because incest behaviors do sometimes occur, and details of the taboo are different in different cultures.
Incest taboo is a "permitted" culturgen; indeed, it is a predisposition that the genes have been coding for during all of human and pre‑human ancestry. Therefore, any genes that influence incest behavior will be under selective pressure, and can be quickly selected into existence if they exhibit adaptive nuances ‑ such as favoring first‑cousin matings.The following hypothetical culturgens illustrate the range of likely to unlikely: 1) the celebration of successful warriors versus scorning them, 2) offering help to fellow tribesmen versus offering help to neighboring tribesmen, 3) sharing food with relatives when there's extra food versus denying food to relatives, and 4) adopting tribal culturgens versus mocking them. The genes aren't "dumb," and not all culturgens have an equal chance for acceptance.
The "other side of the coin" is to ask if the evolution of genes can be affected by an entrenched culture? The key word here is "entrenched." There is a tendency for all members of a tribe to adopt the same culturgens, a noticeable human trait called "conformism" (Boyd and Richerson, 1996; Henrich and Boyd, 1998). In sharing a culture, people adopt most of its culturgen elements. There must have evolved a gene for a brain function that causes individuals to be unquestioning joiners, and all people have the gene.Consider a person who is more willing than others to try out new culturgens. Not only will he be burdened with many new culturgens, most of which will be maladaptive, but his beliefs and behaviors will make him resemble someone from another tribe. Since every tribe is in conflict with neighboring tribes, a person who appears to belong to another tribe will be severely handicapped in gaining acceptance by his own tribe. Unless this open-minded individual happens to adopt a highly adaptive culturgen, his aberrant beliefs and behaviors will not be tolerated by his fellow tribesmen and he will be banished by them. Therefore, any gene that inclines a person to be open-minded is likely to quickly disappear from the human genome.
Yet, new culturgens do occasionally appear. So there must be a mental calculus of perceived benefit versus cost that allows some individuals to adopt a new culturgen without being banished. Perhaps tribesmen who have attained a position of unquestioned tribal loyalty are able to try out mildly new culturgens with impunity. If a successful huntsman uses a new arrowhead shape, then other tribesmen may be curious about it and may eventually adopt it. If the chief attributes a tribal victory to a new spirit, the others may consider accepting this new spirit. Everything new has a barrier for acceptance. If enough individuals are willing to overcome their natural resistance to a new idea then a generally-accepted culturgen shift within the tribe might eventually occur. If this happens, then those who remain uncomfortable with the new culturgen would be at a disadvantage, and the gene that codes for their culturgen preference would face a slow extinction.This illustrates how culture may influence the evolution of genes.
To cite a specific, hypothetical example illustrating the co‑evolution of genes and culture, imagine the first groups of Africans to migrate northward after the start of an interglacial warming. Upon reachingIn this new land with seasons it makes sense to establish a home base in the fall where food provisions can be kept for use throughout winter. New customs are needed, as are new instincts. Whereas jungle life has no rewards for those who store food, glacier's edge life demands it! The impulse to eat whatever food is present is now a liability. Impulse control on this, and other matters, is important. Conscious thought is brought to bear on such tasks as providing food stores for the winter, protecting these stores from theft by animals (and other human groups), planning ahead by making winter clothes from animal skins while the skins are available, finding a cave before others, constructing a shelter, and many other season‑related tasks.
Europe, the migrants would have encountered retreating glaciers, rivers of melt water, abundant plant growth, grazing animals, and slow‑moving Neanderthals (distantly related to humans). These migrations might have occurred 120,000 years ago, 70,000 years ago, and 13,000 years ago (but, in this last case, the migration would not have encountered Neanderthals, who were displaced by humans about 30,000 years ago). The new setting presents many opportunities, but it also demands many behavioral adaptations. Seasons are more extreme, and procuring food in winter is different from summer. Uneaten food doesn't spoil as quickly as in the jungle, so food storage is not only possible, it is essential to avoid starvation in the winter.
As described earlier, every population of individuals will exhibit a spectrum of pre‑adaptations and pre‑maladaptations to a totally new challenge. Those who are naturally inclined to possess impulse control, for example, will be inclined to adopt culturgens requiring impulse control. In the absence of a large tribe with an entrenched culture, individuals are freer to discover their innate "usage probabilities" for new culturgens. The transition from a previous culturgen to a competing new one, is set by the genes, but is also dependent on the situation (physical environment, social setting, etc). People in the same situation will have different "transition probabilities." Those who are quicker to make the transition to the new culturgen are relatively "pre‑adapted" to the new setting.Whereas such pre‑adapted people did not have a competitive advantage in the jungle, they are the new winners in a mid‑latitude setting. Their pre‑adapting genes create more successful individuals, and their genes will spread through the gene pool of those groups that migrate north.
As a new collection of culturgens accumulate, creating a new culture, some genes become mal‑adapted (to the new culture). For example, genes for impulsivity handicap individuals with that gene. If those people fail to set aside winter food stores, and are forced to steal from neighbors during the winter, they are at greater risk of injury or death by those who are protecting their food stores. Agreements may be formulated among like‑minded provisioners, requiring the group to take action against those who don't respect other people's "property." An individual who has trouble grasping the new concept "property" and "property rights," and the consequences of "stealing," will be dealt with harshly by the majority, once these new culturgens are adopted.These examples illustrate how a new environment can change culture, and how a changed culture can influence the fate of genes, causing gene allele frequencies to change. As one change becomes established, new selection pressures exist on the other. And selection pressures work in both directions: new genes alter "transition probabilities" for the adoption of new culturgens, and newly adopted culturgens alter the selection pressure on genes. Thus, genes and culture co‑evolve.
I claim that when tribes began to subsidize the full‑time employment of artisans, possibly during a warming 70,000 years ago, the stage was set for an explosion of new artisan‑like niches, and that when the Holocene interglacial began, some 12,000 years ago, the explosion of changing cultures began. The new niches include such things as agricultural farmer, domesticated animal farmer, tribute record keeper, clothier, entertainer, priest, government administrator, entertainer, merchant, full‑time soldier and others.Before these changes began everyone within a tribe assumed the same roles, which dealt mostly with providing food and fighting neighboring tribesmen. The Holocene saw fewer and fewer people engaged in the traditional, all‑roles lifestyle; an ever‑increasing fraction of people in urban centers became engaged in specialized roles, having nothing to do with food production or fighting wars. Country living yielded to living within or close to cities. Culture became more complex, powerful, and played a growing role in the selection of gene alleles that were pre‑adapted for new niches. This is the story of the expansion of culture and the birth of civilizations.
Defining CivilizationLet us ponder the term "civilization." Like most people, I know it when I see it, but it may nevertheless be instructive to struggle with defining it.
Perhaps the root word "civil" is the key to its definition. Where civil social interactions are common, there resides a civilization. However, uncivilized primitive people are usually "civil" to each other ‑ but their "civility to strangers" is another matter? It is well known that the "tribal mentality" (Spencer, 1892) requires that two separate codes of morality be used; one is meant for intra‑tribal interactions (amity) and the other for extra‑tribal interactions (enmity). However, when neighboring tribes trade goods, they are civil with each other. Even if that's due to a fear of retribution, fueled by not knowing the ferociousness of the stranger tribesmen, "civility to strangers" still lacks the essential trait we're looking for.I'm going to suggest a definition based on an observation that has probably never been suggested before. I assert that a civilization is the product of left‑brained values and productive activities. Consider the dictionary definition: civ·i·li·za·tion, n. 1. An advanced state of intellectual, cultural, and material development in human society, marked by progress in the arts and sciences, the extensive use of writing, and the appearance of complex political and social institutions. Note how left brained these qualities are: material and intellectual developments, writing, science, complex social political and institutions. These are things that left brains value and only they can do!
The dictionary's phrase "the appearance of complex political institutions" conceals a deeper truth about civilizations. One of the functions of complex political institutions is to safeguard the rights of individuals from violation by the collective. I believe that ever since the left brain began its specializations for what we now recognize as LB‑style thinking there has been a conflict between obligations imposed upon the individual by the group versus LB‑style individual aspirations. The group wants conformity, and it endeavors to suppress individual expression. Those individuals who identify with group conformity are agents of the collective will, which is to say, they are dupes of the genes! For it is the individual with an independent will, fortified by a strong LB, who is unwilling to remain subservient to its RB, who can show the way to liberation from the genes that wish to keep us dedicated to serving their "needs." LB‑style individuals protect themselves from exploitation by the genes by constructing political institutions, such as a legislature, a police system, and a justice system. When these institutions work, they control the collective's meddlesome intimidation of the individual who is minding his own business as he creates his own individual path through life.Too often the political institution is hijacked by the enemy of the individual. Communism is a case of the collective usurping power from those who created the institutions to protect the individual from the insidious meddling of the collective. I believe that communists are well‑meaning, but misguided by a naive understanding of human nature. They mistake society for the family. Within a family it is natural for each to take from those who have and give to those in need. This makes genetic sense, since the members of a family have a strong genetic relatedness to each other. It even makes sense for a tribe to behave in this communistic way, though to a lesser extent than for the family. But human nature will not endure the attempt to bestow family and tribal obligations to the larger social group of a society. Society can never be made to look like a family, or small tribe. Human nature has been molded for competition with neighboring groups, and it mobilizes our energies to defeat them. Communism must suppress individualism; it symbolizes the classic conflict between the needs of the collective and the aspirations of the individual. Communism is the enemy of everything valued by LB. LB wishes to liberate the individual from the collective, and communism thwarts these liberating ambitions.
The dictionary definition also refers to progress in the sciences. Science is a discipline that requires strong LB involvement. For a scientist, RB must play a supportive role, though it does "point the way" and "give opinions" when its intuitive feel for matters is useful. During my practice of science (in the physical sciences) my RB contributions have been important, but supportive. I will share credit with RB for my four patents, and other creative labors. Intuition is an essential guide through the labyrinth of possibilities faced by a researcher in any branch of science. Hunches that pay off advance every investigation. But the entire enterprise is overseen and guided by a disciplined LB. After the inspiring moment (which has happened to me many times), while the emotional excitement swells, LB goes into action and begins to "work out" the idea. Logical consequences of the idea are pursued, and tests of it are devised. A moment's inspiration can lead to many years of an unfolding, LB‑guided investigation. Without a specialized LB, science could not progress.<>As an aside, I believe the inclusion of "art" in the dictionary definition is a mistake. If we somehow could remove all the "arts" from Western civilization, would we still think it was a civilization? Imagine that we had the same level of literature, science, technology, musical heritage, material standard of living, sophisticated governing institutions, medical knowledge, and insight into how things work, I claim that we would still call it a civilization. Primitive societies have their "art" ‑ and sometimes it's quite good art, easily rivaling "modern art" in appeal. Cro-Magnon artistic renderings are impressive, yet they did not possess a civilization. I maintain that "progress in the arts" is not an essential aspect of a civilization.
The dictionary definition for civilization refers to "the extensive use of writing." Writing is an LB activity, with key roles for both Broca's and Wernicke's areas, and others within LB. True, RB plays a role, but it is a supporting role, similar to the role I described for the pursuit of science. If RB tried to write by itself, it would lamely produce pat sayings, open interpretation poetry, and profanity; it would be unable, for want of a Broca's area, to produce syntactical prose. This much we know from brain research, that reveals what RB is capable of verbalizing when LB has been disabled.<>There are more candidates wishing to be called a civilization than are deserving of it, the way I prefer to define "civilization." For example, the Mayan is often referred to as a civilization. The more we learn about it, the more despicable it appears to have been. For every trace of accomplishment, there are several barbaric, bloody practices. Yes, their artisans devised a complex calendar, and massive stone pyramids and temples, but they were used for the most inhumane ceremonies in the human record. The Mayans are an embarrassment to humanity! The Mayan individual was a victim of his culture (I will grant them "culture" status, but not civilization status). I pity those poor LB‑style Mayan artisans who must have existed, for their labors were used to advance a collective appetite for brutality that only crazed contemporaries could admire. It appears that the insane Mayan culture was the captive of a right brain that was answering every call of the reptilian brain. Anyone with a strong LB would have had a limited opportunity to influence societal values, and would have been relegated to improving the calendar, overseeing the construction of killing temples, and fiddling with hieroglyphs for recording the glorious deeds of their murderous employer.
Most so‑called civilizations are a mixture of the Mayan type (regrettably dysfunctional) and the ancient Greek example (admirable). The early Greek civilization produced truly ground‑breaking insights into the nature of reality and Man's place in it. I will not present a systematic listing of civilization candidates, and their salient features. Rather, I will use three civilizations from among the many to illustrate dynamics that to some extent must have been present in them all. Let us first consider the rise of one of the first civilizations, the Minoan, and try to learn what drove its ascent.Civilization Growth Phases
The Minoan civilization grew through three stages: an Early Period, 3000 to 2100 BC, a Middle Period, 2100 to 1600 BC, and a Late Period, from 1600 to 1326 BC, which came to an abrupt end when the volcano on the
erupted and, by destroying much of their infrastructure, rendered them helpless against invasion by the Mycenaeans. A tsunami probably destroyed the coastal settlements along islandof Thera Crete's north shore, where the Minoan civilization was also present. Prior to their demise, the Minoans were merchants and traders. They plied the Mediterranean, moving products from port to port for profit. Their merchant ships were well designed, and very functional. They had multi‑story residences, with water delivered to some of them, aqueduct style. Their standard of living must have been one of the best for their time. The Minoans were a peaceful people, as they apparently had no army. Their art was elaborate and accomplished, and when the subject matter included humans it was usually related to athletic performances, dancing, and never warriors, battle scenes or angels.
Although I do not consider "art" to be an essential component of civilization, it can be used to understand something about the nature of their society. Art can also be used to provide clues to the evolution of their rise to power. Consider the samples of pottery from each of the three periods, and note the style they used to form and decorate them.
Figure 10.1 Samples of Minoan pitchers and vases from the Early, Middle and Late periods. From Time‑Life Books (1975).
Ask any neuropsychologist to view the above sequence of vases, and he will immediately recognize that there's a progression from a functional form preferred by the left brain to a decorative form preferred by the right brain. LB prefers straight lines and functional shapes; RB prefers curved lines, ornamentation that is elaborate, bizarre and sometimes incongruous (i.e., like the baroque style) and extra flourishes that may detract from functionality.What could this progression of patterns mean? Assuming that artisans made what their patrons wanted, it means that people in power during the Early Minoan Period were LB‑styled, whereas by the Late Period the power had shifted to RB‑style people. And, assuming that this interpretation is correct, how could this factoid illuminate our understanding of how civilizations ascend? It says, I believe, that the earliest stage of a civilization's rise is driven by LB‑style people. And it also says that during the unfolding of a civilization the reins of power are captured by RB‑style people. This last speculation will be taken up in the chapter that deals with the decline of civilizations.
In Chapter 15 I present evidence that the per capita output of technological innovations rises over time to a peak, then subsides ‑ while the economic activity of the civilization continues toward a peak that occurs a few centuries later. In the case of the Greco‑Roman civilization, the population peak (a proxy parameter for economic activity) followed the innovation peak by 5 centuries. In the case of the present Western (European‑American) civilization, the population peak will follow the innovation peak (which occurred in 1900 AD) by at least a century, and probably two centuries.The innovation peak corresponds to a period when society gives the greatest freedom to LB‑style people, by celebrating their efforts, paying for their services, giving them a status that exempts them from warrior service, and publicly recognizing that LB activities are good for the general welfare. As I argue in the next chapter, RB‑style people are "people‑oriented" as opposed to "artifact oriented," and they are good at manipulating other people for their personal gain. This talent of one segment of the population leads to a gradual displacement of the LB‑style people from power, thus explaining the shift in preferred art form during the course of a civilization's unfolding.
The world's innovation per capita has two major peaks, one at 300 BC and the other at 1900 AD. We know more about the recent peak, so let's consider it from the standpoint of LB versus RB. It is generally recognized that 15th and 16th Century Renaissance led to the 17th Century Enlightenment, which led to the explosion of 18th and 19th Century industrialization. The Enlightenment was a unique chapter in human history, generated by a changed "climate of opinion." The intellectual atmosphere was dominated by thinkers who, like Voltaire, penetrated the cobwebs of previous centuries and saw things the way they were. Voltaire was a nuisance to the church, politicians, and traditional intellectuals because he would not be tamed. He saw through the posturing and pretense of phony pontifications and despised the veneer of social acceptability; instead, he was cynical, skeptical, uncompromising, and had an acerbic wit. He exemplifies the LB‑style artisan. Other Philosophes, like Holbach and Diderot, worshipped the Goddess of Reason, and ushered in the view that it is within human power to create a world, based upon Reason, to replace the old unrealistic dream of aCivilizations Falter
, where perfection and felicity were supposed to dwell for eternity (see The Heavenly City of the Eighteenth‑Century Philosophers by Becker, 1932). The Philosophes promised a new Heavenly City , built on Earth by what can now be seen as LB insights, and guided by LB logic. Heavenly City
The 19th Century began to make good on some of these promises. Inventions just kept coming, insights into physics accelerated, andThe Apollo program that landed 12 men on the moon was LB's last hurrah! From the social upheaval of "The Sixties" came a change in the "climate of opinion" ‑ which lasts until today. LB accomplishments didn't stop, and in fact continue to be made use of, but they were not publicly applauded (except for an occasional rover on Mars or Hubble Space Telescope picture). Political correctness was created to discredit and stifle LB values. The greatest insight that Mankind has achieved occurred midway through the last half of the 20th Century, yet almost no one knows about it today. Mankind's greatest discovery is Sociobiology! It is the crowning achievement of LB thinking. It is comparable to the 19th Century's discovery that the physical world is reducible to the invariant laws of nature. Sociobiology forces living systems into this physical world, and accomplishes the supreme feat of Reductionism ‑ everything, including life, is governed by invariant physical laws, and all happenings reduce to an unfolding of physics, where a = F/m and quantum physics determine everything!
presented the world with one of mankind's greatest insights into where we came from and who we are ‑ all based on LB observation and reason. The pace of discovery and industrialization continued into the 20th Century, starting with Einstein's succession of profound insights into the nature of the physical world. Science, technology and engineering were held in high public regard ‑ until the Great Depression. For a decade, during the global depression in both Darwin Europeand the , a malaise stifled the spirit, and it questioned LB's warrant for carrying the Torch of Progress. Criticism of society was suddenly unwelcome (poor H. L. Mencken lost audience). For 15 years serious thinkers were contemplating the end of civilization, as Diderot and the other Philosophes had worried might happen during the 18th Century. World War II resurrected the reliance upon technology for weapons, and the engineer was again cast as savior. The atomic bomb kindled the bittersweet importance of science. Sputnik forced a new dedication to giving power to the scientists and engineers, not because of a desire to build that dreamed of U.S. on Earth, but out of concern for national survival. Heavenly City
My measure for a civilization is that people have an honest understanding of who they are. If only a few percent have this glimmer of understanding, it constitutes a civilization. The Greeks qualify, thanks to such luminaries as Thales of Miletus, Anaximaner of Miletus, Democritus of Abdera, and some of the ancient Romans qualify, thanks to thinkers like Lucretius. The 20th Century, Western Edition, qualifies because of such sociobiologists as W. D. Hamilton, G. C. Williams, Robert Trivers, Edward O. Wilson and Richard Dawkins.The Chinese have seen many civilizations rise and fall in their land, and during the past millennium they have often been more advanced than their contemporary European civilization on measures commonly used to describe civilization. Their technologies raised living standards, but as far as I can determine they repeatedly failed the boldness test concerning the quest of insight into the nature of reality. Their "philosophy" suffers from an excess of intuitive, RB style nonsense! In my opinion they never achieved the level of insight of Thales, Democritus or Lucretius, and their 19th and 20th Century stifling "collective versus individual" culture has made them bystanders while Western thinkers explored beyond the Greek giants, led by Schopenhauer, Bertrand Russell, and the sociobiologists.
On many occasions the Chinese abandoned their relatively advanced technology, and reverted to living in an RB world. This "failure of nerve," or unwillingness to pursue Truth into areas where it "hurts," constitutes what seems to me to be an endemic Oriental flaw. Their practice of physical science suffers from the same intellectual timidness. Even though the Chinese score higher on IQ tests than all other races (except the Jews), there's something about their frontal lobes, or something about their RB‑style of thinking, that causes me to question their ability to boldly advance human understanding of big picture matters on "the nature of existence" or "who we are." Until they allow the individual more freedom from the will of the "collective" the contributions of the Chinese civilization will be confined to mostly engineering. This, I'm sorry, is my humble opinion.Thanks to a specialized left brain, two great civilizations, by my reckoning, have arisen during recorded history. I rank them "great" because they celebrate the individual, and they bring us closer to a stage of human evolution when we shall subdue the collective mentality. Outlaw genes created this desire to conform to what's good for the collective good, and we are now discovering that we have been dim‑witted slaves too long! LB is leading the way to emancipation, and it is accomplishing its feat by creating civilizations. The job of liberation has not been accomplished; but the stage has been set for it's serious pursuit.
Thus we stand at the cusp of two millennia, looking back at many failed civilizations, at least two great ones, and wondering where ours is headed. Most people are unaware of human servitude to the genes and the collective they've created; while others, like me, wish for liberation and wonder if this next will be the century when humanity's emancipation will finally be achieved. If my claim is true that each civilization is the result of LB efforts to improve the life of the individual, with the unforeseen consequence of bringing the individual closer to liberation from the grip of outlaw genes, then we have a tool for discerning the health of today's civilization, and predicting its future
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