Does Natural Selection "Disfavor" the Educated? What Genetic Research Shows

Contents:

• How can one connect the tendency to have many (or few) children with genetic characteristics?
• What has research shown about the connection between education and natural selection?
• "Nature" or economics? How can this effect be explained? src="https://blog.skillbox.by/wp-content/uploads/education/estestvennyy-otbor-ne-lyubit-obrazovannyh-chto-pokazyvayut-geneticheskie-issledovaniya/0844c9cc97de44ae98a85b393916fb1c.webp" class="attachment-author_image size-author_image" alt="" decoding="async" />

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  In this article, we will cover the key aspects of the topic. You will receive information on the most important points that will help you better understand the subject matter. Learn what factors influence the situation and what decisions can be made to achieve the desired results. We will also consider practical examples and tips that may be useful in your practice. Read on to deepen your knowledge and improve your competence in this area.

  • How can the tendency to have many (or few) children be linked to genetic traits (what are polygenic scores).
  • Which study recently showed that people with a genetic predisposition to a high level of education leave fewer offspring.
  • Does nature, in the form of natural selection, really have something against the widespread dissemination of a propensity for education?
  • How can this effect be explained from the point of view of the economic theory of fertility (and what is its essence).
  • How can the effect of “high genetic predisposition to education means low fertility” be prevented?

  Some researchers hypothesize that human intellectual abilities decline with each new generation, and this may be a consequence of evolutionary processes. They argue that natural selection does not favor the spread of genes associated with learning and mental abilities. This viewpoint is controversial in the scientific community, as many aspects of intelligence development depend not only on genetic factors but also on educational and social conditions. Nevertheless, the importance of studying the influence of evolution on intelligence remains a pressing topic in the fields of psychology and genetics.

  There is a belief that people who are not predisposed to learning have more offspring, while those who are predisposed to learning have fewer. Is this statement true or a myth? What data are these conclusions based on, and how valid are they? These questions are addressed in an article published last year in the scientific journal Behavior Genetics. The study analyzes the relationship between predisposition to learning and reproductive behavior, which may provide new perspectives on understanding evolutionary mechanisms.

  It is important to note that such studies focus on correlations, not direct cause-and-effect relationships. Anna Pavlova, a postgraduate student at the Higher School of Economics and a researcher at the Center for Interdisciplinary Research at the Russian Academy of Education, emphasizes that even if there is a strong correlation, the claim that "it's all in the genes" is an oversimplification. There are numerous unobserved variables that can influence the study's results.

  How can one even link the tendency to have many (or few) children to genetic traits?

  The study, titled "Natural Selection in Three Generations of Americans," is based on data from the American Health and Retirement Survey, which involved 8,827 people, mostly born between 1920 and 1960. All participants provided DNA samples in 2006–2008. Since the majority of respondents were white, the researchers also collected genetic data from 2,319 Black Americans from similar age groups. This provides a more comprehensive understanding of natural selection and its influence on health and genetic characteristics in various populations in the United States. Based on the genotypes obtained, the researchers assessed the participants' predisposition to successful and long-term educational attainment, as well as good health and fertility. These parameters can indeed be determined through DNA analysis, opening new horizons in the field of genetics and its influence on human life outcomes. Studying genetic factors allows us to better understand how heredity influences educational achievement and reproductive ability, which in turn can contribute to the development of more effective educational and healthcare methods.

  

  Databases exist that record genetic variants that are more common among people with a high level of education, among those who rate their health as "excellent," and among those who become parents at a young age. For each of these characteristics and many others, polygenic scores (indices) have been determined, allowing us to analyze the influence of genetic factors on various aspects of a person's life. These data can help study the relationship between genetics and social factors, as well as develop strategies to improve the health and well-being of the population.

  Scores were calculated for various medical conditions, including a predisposition to myopia, migraines, and alcohol abuse. Behavioral characteristics, such as interest in reading in childhood and life satisfaction, were also taken into account. These data help better understand the influence of genetic factors on human health and behavior.

  Polygenic scores are a method for assessing the genetic contribution of different alleles to specific phenotypic traits, such as intelligence, personality, and other aspects of behavior. This term is discussed in detail in the book "Behavioral Genomics: Child Development and Education," written by scientists from the Russian Academy of Education and Tomsk State University. This book describes how polygenic scores aid in studying the influence of genetic factors on children's development and their educational achievement. Polygenic score calculations are based on large volumes of genetic data and allow one to predict the likelihood of an individual expressing certain characteristics, which is important for understanding the role of genetics in learning and development.

  The human genome consists of three billion base pairs, including adenine, guanine, cytosine, and thymine—the four key "letters" of the genetic alphabet. Remarkably, 99% of this genetic material is virtually identical in all people. However, differences of just 1% of the total number of nucleotides can have significant consequences. Typically, these variations are single-nucleotide substitutions or small insertions of genetic information. These changes can influence physical and biochemical characteristics, as well as predisposition to various diseases. Understanding genetic differences is key in the fields of genetics and medicine, as it allows for the development of personalized approaches to treatment and disease prevention.

  Many differences in human characteristics are not overtly apparent. Geneticists argue that most traits are influenced by multiple genes, a phenomenon called polygenic influence. This means that each gene contributes to the development of a specific trait. Differences in these genes determine whether an organism has a trait and how it is expressed.

  Genome-wide association study (GWAS) technology has opened up new horizons in identifying genetic variants that influence the expression of various traits. With GWAS, as described in the book "Behavioral Genomics," researchers can simultaneously analyze hundreds of thousands of DNA markers, including single nucleotide polymorphisms and other small genetic differences, to identify their association with various phenotypes. This methodology significantly accelerates progress in the field of genetics, enabling a deeper understanding of how genetic factors influence human health and behavior.

  A polygenic score is a summary of data on many genetic variations, not just one specific DNA mutation. It contains information about a set of genetic differences observed in thousands of people with certain traits. This includes features associated with mental ability, such as IQ, years of education, and school performance at age 16. Such data helps better understand how genetic factors influence cognitive characteristics and educational achievement.

  People with high IQs often have similar genetic traits in their DNA. These genetic variations are also associated with other characteristics, such as health, behavior, and personality traits. However, a polygenic score does not accurately predict that a person with certain genetic variants will necessarily exhibit the corresponding traits. It merely indicates an increased likelihood of their expression.

  Current polygenic scores have limited predictive power. For example, a score associated with educational attainment can explain only 12–16% of the variance between individuals in this aspect. This is because even the most favorable combination of genes requires an appropriate environment to express itself. Educational attainment is largely determined by the environment in which a child grows up, their individual experiences, as well as their health and personality characteristics. However, genetic factors also contribute to differences in educational attainment.

  

  In an article published in In the journal Behavior Genetics, researchers analyzed 68 polygenic scores and correlated them with relative lifetime reproductive success. This study focuses on the number of children sired by individuals with these genetic scores, allowing us to assess the influence of genetic factors on reproductive outcomes. The results of this analysis may help better understand the relationship between genetics and human behavior and identify the mechanisms that influence reproductive strategies.

  This indicator is relative, as the number of children each participant has is compared with the fertility of their peers. The calculation is based on the following formula: the number of children each individual has divided by the average number of children born in the same year for all participants. This allows us to obtain a more accurate picture of fertility in the context of a particular generation.

  High values ​​of this indicator indicate reproductive success of an individual, which facilitates the spread of their genetic variants. At the same time, the genetic material of people with low reproductive success gradually disappears from the population. This reflects natural selection, which favors those genes that provide high reproductive ability and adaptability to the environment.

  What the study showed about the connection between education and natural selection

  The study in question demonstrated that genetic variants associated with high levels of education are more common in people who have a small number of children. This suggests that individuals with a genetic predisposition to learning tend to have fewer offspring. Thus, the relationship between genetics and educational level can influence reproductive strategies, which opens new horizons for understanding the interaction of genetic factors and social behavior.

  The study showed that the reproductive success of the parents and children of the participants is directly related to the number of siblings, as well as grandchildren. It turned out that the parents of people with a high polygenic score for predisposition to learning did not create large families, and their children also had fewer offspring. Although the researchers did not have DNA data for the parents and children, consanguinity implies that they may share certain genes associated with learning. These findings highlight the importance of genetic factors in shaping reproductive strategies and educational achievement.

  Apparently, a genetic predisposition to learning may have a negative impact on fertility in three consecutive generations of the families studied. Individuals with a high propensity to learn tend to have fewer children and grandchildren of their own. This may be because their children also do not aspire to have many descendants. Thus, genetic factors may influence demographic trends in families where learning and knowledge play an important role.

  Polygenic score studies have shown that a high predisposition to good health is positively associated with reproductive success. In contrast, the presence of unhealthy habits, such as smoking, is often associated with fewer children. These findings highlight the importance of health and lifestyle in the context of reproductive fitness.

  "Nature" or Economics? How Can This Effect Be Explained?

  Why were these results obtained? A likely reason is that natural selection favors only those genetic variants that promote reproductive success. At the same time, factors such as personal happiness, professional achievement, power, or longevity are not the focus of natural selection—nature has no interest in them. Research suggests that reproductive success may be associated with reduced lifespan, suggesting that natural selection may favor genes associated with shorter lifespan.

  

  Natural selection does not work against individual achievement or longevity, but rather selects for characteristics that facilitate reproduction. If a trait associated with personal well-being, such as the ability to build strong relationships or high work capacity, increases the chances of successful reproduction, then natural selection will favor its consolidation in the population. Thus, traits that promote both personal success and reproductive potential are more likely to survive and be passed on to their offspring.

  Some traits that promote reproductive success are useful for more than just passing on genes. For example, good physical and mental health are valuable assets for every individual. However, the relationship to intelligence and learning ability remains controversial. It is important to consider how these aspects influence reproductive success and overall quality of life, as well as their role in modern society. Intelligence can improve adaptation and survival, but is not always directly related to reproductive achievement.

  The ability and opportunity to obtain an education do not arise in a vacuum. Typically, such opportunities are available to people with acceptable health, mental state, and living conditions. A large-scale study conducted by Anna Pavlova shows that a polygenic index associated with high educational achievement is positively correlated with overall health. This underscores the importance of a holistic approach to education that encompasses not only intellectual ability but also physical and psychological well-being.

  There is no reason to believe that people predisposed to intellectual work are more susceptible to disease. On the contrary, a high level of education is an indirect indicator of health and living conditions suitable for procreation. In most countries, obtaining a high level of education is also associated with increased income, which allows for the provision of a large family. Thus, intelligence and education can contribute not only to personal development but also to the promotion of health and well-being in society.

  Good health, comfortable living conditions, and prosperity would seem to contribute to an increased birth rate. However, genetic studies show different results. The reasons for this paradoxical situation may be related to lifestyle changes, economic factors, and social conditions. For example, modern couples often postpone starting a family due to career aspirations or financial considerations. These aspects require in-depth analysis to understand how they influence fertility in a prosperous environment.

  Certain genetic variants may increase the likelihood that a person will decide to have fewer children. However, this connection is indirect, as a person's conscious choice is significantly influenced by the environment, argues Anna Pavlova. It is important to consider that factors such as social, economic, and cultural aspects play a key role in the decision to have children. Genetic predispositions may be only one of many factors shaping family plans and views on parenthood.

  One article examines polygenic indices that correlate with high intelligence. High intelligence, in turn, is associated with high levels of education, and high levels of education are associated with low fertility. This study found no direct association between genes associated with high educational attainment and child number, after accounting for intervening variables. Furthermore, in the largest study to date, the negative correlation between the polygenic score associated with educational attainment and child number did not reach statistical significance for either men or women. Thus, it can be concluded that educational attainment has a greater influence on child number than genetic factors.

  The authors of the article in the journal Behavior Genetics discuss the relationship between educational attainment and fertility, citing the economic theory of fertility proposed by Nobel Prize-winning economist Gary Bakker. They emphasize one of his key points: as education increases, the value of a person's time in the labor market increases. This leads to high costs of giving up earnings for the sake of having children, which may explain the observed association between education and the number of children.

  

  The key idea of ​​the theory focuses on mothers who strive to combine a career and motherhood. Women with successful careers, working in highly skilled and competitive fields, fear that after a break for childbirth and childcare, they will have difficulty returning to their previous positions. This concern about lost opportunities and the level of competition in the labor market becomes a significant factor influencing decisions about family planning and professional development.

  Women in unskilled and low-paid positions, when going on maternity leave, realize that they can quickly find a similar job with a minimum income after the birth of a child. Importantly, such considerations often do not take into account job-protected parental leave and other social benefits. This may be due to the fact that Bakker's study was based on historical data covering a century, during which such guarantees were not universally available. Thus, the impact of childbearing on women's financial situation requires a more in-depth analysis of contemporary realities, including the availability of social benefits and government support.

  Gary Bakker has spent decades developing the economic theory of fertility, and his ideas, cited in the Behavior Genetics article, go beyond simple propositions. He identified another reason for declining fertility in economically prosperous developed countries, in addition to inadequate social protections for women.

  In one article, the scientist developed an economic model that ignored gender differences and treated people as abstract economic agents. In this model, the cost of raising children was assessed as an investment, compared with investment in developing one's own human capital. His calculations showed that in countries with a high demand for skilled workers, it is more economically feasible to invest in oneself than in raising children, if this issue is considered solely in terms of return on investment. These findings highlight the importance of analyzing economic decisions made in the context of personal investments and their long-term effectiveness.

  The author's research also includes less abstract data, such as the relationship between parents' education and their investment in their children's education. Educated parents strive to ensure that their children also receive a high-quality education. However, they may prefer to have fewer children to ensure that each of them receives a level of education comparable to their own.

  Let's return to the interpretation of the economic theory of fertility, which the researchers applied when studying the DNA of American retirees. This theory provides a unique perspective on the influence of economic factors on demographic processes. By analyzing the genetic data of retirees, the authors sought to identify links between economic status and reproductive trends. Thus, this study opens new horizons for understanding the interaction between economics and fertility in different social groups.

  The study confirms Gary Bakker's theory that individuals with a high genetic predisposition to education, both women and men, experience a shorter time to childbearing. This is due to the fact that such individuals place greater emphasis on career development. However, it is possible to minimize the negative consequences associated with a temporary withdrawal from the labor market. In this context, financial stability serves as a reliable protection. Gary Bakker predicted that in high-income groups, a high level of education among women would not lead to a decrease in fertility, since financial resources allow them to take fewer risks with their professional status.

  A study conducted in the UK and published by David Hugh-Jones in 2022 confirmed that education did not have a negative impact on fertility among wealthier segments of the population throughout the 20th century. At the same time, in low-income groups, the opposite trend was observed, where natural selection acted against educational attainment. This study highlights important social and economic factors that influence fertility and educational achievement across different segments of society.

  

  The American data do not reveal any differences between social groups, which remains unexplained by the study's authors. This may be due to the limited sample size used in the American study, which consisted of only 10,000 people. Meanwhile, the British study relied on data from over 400,000 participants, which significantly increases its reliability and allows for a more in-depth analysis. This difference in sample size may be a key factor in interpreting the results and understanding social trends in both countries.

  Earnings are only one aspect of life, and they are not always the most significant. Anna Pavlova emphasizes that the idea of ​​people as rational machines striving only for maximum gain is outdated. Personal values, attitudes, and qualities, as well as social norms, play a significant role in matters related to having children. The number of children one will have cannot be considered genetically programmed. This becomes evident when considering the demographic transition: just a few decades ago, it was common for families to have four or more children, whereas in modern society, families with one or two children are more common. Genetic changes in the population could not have occurred so rapidly, but environmental conditions and social factors have undergone significant changes.

  People with a high genetic predisposition to education tend to have fewer children. This is because they are more likely to invest in their careers and recognize the risks associated with leaving the labor market to have children. They also strive to provide a high-quality education for their children, which becomes financially burdensome when having many children. Reducing these risks, for example through government guarantees, can change the situation, and the effect of low fertility among educated people can be minimized.

  Reading is an important aspect of development and learning. It helps broaden horizons, improve vocabulary, and increase literacy. Furthermore, reading promotes critical thinking and the ability to analyze information. Regardless of the genre, be it fiction, scientific articles, or specialized publications, every page read contributes to personal growth and professional development. Therefore, it is important to devote time to reading and choose high-quality sources of information.

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