Birth order
Encyclopedia
Sibling
Siblings are people who share at least one parent. A male sibling is called a brother; and a female sibling is called a sister. In most societies throughout the world, siblings usually grow up together and spend a good deal of their childhood socializing with one another...
s. Birth order is often believed to have a profound and lasting effect on psychological development. This assertion has been repeatedly challenged by researchers, yet birth order continues to have a strong presence in pop psychology and popular culture.
Theories
Alfred AdlerAlfred Adler
Alfred Adler was an Austrian medical doctor, psychotherapist, and founder of the school of individual psychology. In collaboration with Sigmund Freud and a small group of Freud's colleagues, Adler was among the co-founders of the psychoanalytic movement as a core member of the Vienna...
(1870-1937), an Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
n psychiatrist
Psychiatrist
A psychiatrist is a physician who specializes in the diagnosis and treatment of mental disorders. All psychiatrists are trained in diagnostic evaluation and in psychotherapy...
, and a contemporary of Sigmund Freud
Sigmund Freud
Sigmund Freud , born Sigismund Schlomo Freud , was an Austrian neurologist who founded the discipline of psychoanalysis...
and Carl Jung
Carl Jung
Carl Gustav Jung was a Swiss psychiatrist and the founder of Analytical Psychology. Jung is considered the first modern psychiatrist to view the human psyche as "by nature religious" and make it the focus of exploration. Jung is one of the best known researchers in the field of dream analysis and...
, was one of the first theorists to suggest that birth order influences personality
Personality psychology
Personality psychology is a branch of psychology that studies personality and individual differences. Its areas of focus include:* Constructing a coherent picture of the individual and his or her major psychological processes...
. He argued that birth order can leave an indelible impression on an individual's style of life, which is one's habitual way of dealing with the tasks of friendship, love, and work. According to Adler, firstborns are "dethroned" when a second child comes along, and this may have a lasting influence on them. Younger and only child
Only child
An only child is a person with no siblings, either biological or adopted. In a family with multiple offspring, first-borns, may be briefly considered only children and have a similar early family environment, but the term only child is generally applied only to those individuals who never have...
ren may be pampered and spoiled, which can also affect their later personalities. Additional birth order factors that should be considered are the spacing in years between siblings, the total number of children, and the changing circumstances of the parents over time.
Since Adler's time, the influence of birth order on the development of personality
Personality Development
An individual's personality is an aggregate conglomeration of decisions we've made throughout our lives . There are inherent natural, genetic, and environmental factors that contribute to the development of our personality. According to process of socialization, "personality also colors our values,...
has become a controversial issue in psychology
Psychology
Psychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...
. Among the general public, it is widely believed that personality is strongly influenced by birth order, but many psychologists dispute this. One important modern theory of personality states that the Big Five personality traits
Big Five personality traits
In contemporary psychology, the "Big Five" factors of personality are five broad domains or dimensions of personality which are used to describe human personality....
of Openness
Openness to experience
Openness to experience is one of the domains which are used to describe human personality in the Five Factor Model Openness involves active imagination, aesthetic sensitivity, attentiveness to inner feelings, preference for variety, and intellectual curiosity. A great deal of psychometric research...
, Conscientiousness
Conscientiousness
Conscientiousness is the trait of being painstaking and careful, or the quality of acting according to the dictates of one's conscience. It includes such elements as self-discipline, carefulness, thoroughness, organization, deliberation , and need for achievement. It is an aspect of what has...
, Extraversion, Agreeableness
Agreeableness
Agreeableness is a tendency to be pleasant and accommodating in social situations. In contemporary personality psychology, agreeableness is one of the five major dimensions of personality structure, reflecting individual differences in concern for cooperation and social harmony. People who score...
, and Neuroticism
Neuroticism
Neuroticism is a fundamental personality trait in the study of psychology. It is an enduring tendency to experience negative emotional states. Individuals who score high on neuroticism are more likely than the average to experience such feelings as anxiety, anger, guilt, and depressed mood...
represent most of the important elements of personality that can be measured. Contemporary approaches to birth order frequently suggest that birth order influences these five traits.
In his book Born to Rebel, Frank Sulloway
Frank Sulloway
Frank J. Sulloway is a visiting Scholar in the Institute of Personality and Social Research at the University of California, Berkeley, and a Visiting Professor in the Department of Psychology....
suggests that birth order has strong and consistent effects on the Big Five personality traits. He argues that firstborns are more conscientious, more socially dominant, less agreeable, and less open to new ideas compared to laterborns. However, critics such as Fred Townsend, Toni Falbo, and Judith Rich Harris
Judith Rich Harris
Judith Rich Harris is a psychology researcher and the author of The Nurture Assumption, a book criticizing the belief that parents are the most important factor in child development, and presenting evidence which contradicts that belief.Harris has been a resident of Middletown Township, New...
, argue against Sulloway's theories. An issue of Politics and the Life Sciences, dated September, 2000 but not published until 2004 due to legal threats from Sulloway (who claimed its content to be defamatory, although it was carefully and rigorously researched and sourced), contains criticisms of Sulloway's theories, including studies that show conflicting findings.
In their book Sibling Relationships: Their Nature and Significance across the Lifespan,
Michael E. Lamb and Brian Sutton-Smith
Brian Sutton-Smith
Brian Sutton-Smith is a play theorist who has spent his lifetime attempting to discover the cultural significance of play in human life, arguing that any useful definition of play must apply to both adults and children. He demonstrates that children are not innocent in their play and that adults...
make the point that sibling relationships often last an entire lifetime. They point out that the lifespan
Life expectancy
Life expectancy is the expected number of years of life remaining at a given age. It is denoted by ex, which means the average number of subsequent years of life for someone now aged x, according to a particular mortality experience...
view proposes that development is continuous, with individuals continually adjusting to the competing demands of socialization
Socialization
Socialization is a term used by sociologists, social psychologists, anthropologists, political scientists and educationalists to refer to the process of inheriting and disseminating norms, customs and ideologies...
agents and biological tendencies. Thus, even those concerned only with interactions among young siblings implicitly or explicitly acknowledge that all relationships change over time and that any effects of birth order may be eliminated, reinforced, or altered by later experiences.
Personality
Literature review
Literature review
A literature review is a body of text that aims to review the critical points of current knowledge including substantive findings as well as theoretical and methodological contributions to a particular topic...
s that have examined many studies and attempted to control for confounding variables tend to find minimal effects for birth order. Ernst and Angst reviewed all of the research published between 1946 and 1980. They also did their own study on a representative sample of 6,315 young men from Switzerland. They found no substantial effects of birth order and concluded that birth order research was a "waste of time." More recent research analyzed data from a national sample of 9,664 subjects on the Big Five personality traits
Big Five personality traits
In contemporary psychology, the "Big Five" factors of personality are five broad domains or dimensions of personality which are used to describe human personality....
of extraversion, neuroticism, agreeableness, conscientiousness, and openness to experience. Contrary to Sulloway's predictions, they found no significant correlation between birth order and self-reported personality. There was, however, some tendency for people to perceive birth order effects when they were aware of the birth order
Confirmation bias
Confirmation bias is a tendency for people to favor information that confirms their preconceptions or hypotheses regardless of whether the information is true.David Perkins, a geneticist, coined the term "myside bias" referring to a preference for "my" side of an issue...
of an individual.
Other studies have supported Sulloway's claims about birth order. Paulhus and his colleagues found consistent support in self-reports by both student and adult samples. First borns scored higher on conservatism, conscientiousness and achievement orientation. Later borns scored higher on rebelliousness, openness, and agreeableness. The authors argued that the effect emerges most clearly from studies within families. Results are weak at best, when individuals from different families are compared. The reason is that genetic effects are stronger than birth order effects. Recent studies also support the claim that only children are not markedly different from their peers with siblings. Scientists have found that they share many characteristics with firstborn children including being conscientious as well as parent-oriented.
In her review of the research, Judith Rich Harris
Judith Rich Harris
Judith Rich Harris is a psychology researcher and the author of The Nurture Assumption, a book criticizing the belief that parents are the most important factor in child development, and presenting evidence which contradicts that belief.Harris has been a resident of Middletown Township, New...
suggests that birth order effects may exist within the context of the family of origin, but that they are not enduring aspects of personality. When people are with their parents and siblings, firstborns behave differently than laterborns, even during adulthood. However, most people don't spend their adult lives in their childhood home. Harris provides evidence that the patterns of behavior acquired in the childhood home don't affect the way people behave outside the home, even during childhood. Harris concludes that birth order effects keep turning up because people keep looking for them, and keep analyzing and reanalyzing their data until they find them.
Jane Austen
Jane Austen
Jane Austen was an English novelist whose works of romantic fiction, set among the landed gentry, earned her a place as one of the most widely read writers in English literature, her realism and biting social commentary cementing her historical importance among scholars and critics.Austen lived...
's book Pride and Prejudice
Pride and Prejudice
Pride and Prejudice is a novel by Jane Austen, first published in 1813. The story follows the main character Elizabeth Bennet as she deals with issues of manners, upbringing, morality, education and marriage in the society of the landed gentry of early 19th-century England...
, while being a study on a certain form of courtship, also places stringent analysis on the personalities on five sequential daughters.
Intelligence
Since the 1970s, one of the most influential theories to explain why firstborns frequently score higher on intelligence and achievement tests than other children is the confluence model of Robert ZajoncRobert Zajonc
Robert Bolesław Zajonc was a Polish-born American social psychologist who is known for his decades of work on a wide range of social and cognitive processes.-Mere Exposure Effect:...
. This model states that because firstborns mainly have adult influences around them in their early years, they will spend their initial years of life interacting in a highly intellectual family environment. This effect may also be observed in siblings who, although later born, have a sibling at least five years senior with no siblings in between. These children are considered to be "functional firstborns". The theory further suggests that firstborns will be more intelligent than only children, because the latter will not benefit from the "tutor effect" (i.e. teaching younger siblings).
Zajonc's theory has been criticised for confounding birth order with both age and family size, and researchers such as D. F. Polit and T.with one other sibling score higher on tests of verbal ability than laterborns and children with multiple siblings. This observation does support a conclusion, more modest than the confluence model's stronger claims, that smaller families lead to children with higher test scores. However, when the metanalysis tested more specific claims by comparing firstborns against the members of the other groups also occupying the upper performance tier (i.e., singletons and children with one and only one sibling), it found that firstborns do not enjoy any advantage over the members of the other groups, suggesting that either a) firstborns do not enjoy any advantage not also enjoyed by those other groups' members or at least b) to whatever extent firstborns do enjoy unique advantages, members of the other upper-tier groups enjoy offsetting advantages not shared by firstborns.
While more consistent with resource depletion theory (RDT) than with the confluence model, these findings also cast doubt upon the claim that RDT is the sole cause of any correlation
Correlation does not imply causation
"Correlation does not imply causation" is a phrase used in science and statistics to emphasize that correlation between two variables does not automatically imply that one causes the other "Correlation does not imply causation" (related to "ignoring a common cause" and questionable cause) is a...
that in fact exists: Were RDT the exclusive explanation, only children would have an advantage over firstborns (given that siblings divert at least some resources from both "true" and "functional" firstborns regardless of age difference). The metanalysis, however, finds no such effect, leaving open the null hypothesis
Null hypothesis
The practice of science involves formulating and testing hypotheses, assertions that are capable of being proven false using a test of observed data. The null hypothesis typically corresponds to a general or default position...
that other factors, including but not limited to those enumerated in the confluence model, have some offsetting effect. For example, in multiple-child families, academic achievent often serves as one of several arenas in which siblings compete for parental affection and other resources. In well-functioning families, firstborns reap the side effects not only of tutoring younger siblings (see above) but also of competing against those siblings to some degree and strengthening themselves in the process. In families where sibling rivalry
Sibling rivalry
Sibling rivalry is a type of competition or animosity among children, blood-related or not.Siblings generally spend more time together during childhood than they do with parents. The sibling bond is often complicated and is influenced by factors such as parental treatment, birth order, personality,...
reaches a pathological level, and especially when a scarcity of parental resources such as affection exacerbates already-severe rivalry, firstborns may be less willing to give away competitive advantage by sharing knowledge with their siblings, but the firstborns in question will by that same token likely study harder for their own benefit, gaining reinforcement similar to what they would realize
Learning by teaching
In professional education, learning by teaching designates currently the method by Jean-Pol Martin that allows pupils and students to prepare and to teach lessons, or parts of lessons...
from the teaching process. In each case, other factors at least partially offset the obstacles to achievement that resource depletion poses, especially in the context of comparing siblings' achievements to those of singletons who engage in neither tutoring nor inter-sibling competition. Moreover, younger as well as firstborn siblings benefit from the process of competing for parental resources that are finite even when they are abundant, meaning that resource depletion is not the only factor in play even for children in the "lower tier," that encompassing laterborns and children with multiple siblings, who do not enjoy any advantage not also enjoyed by
Pareto efficiency
Pareto efficiency, or Pareto optimality, is a concept in economics with applications in engineering and social sciences. The term is named after Vilfredo Pareto, an Italian economist who used the concept in his studies of economic efficiency and income distribution.Given an initial allocation of...
firstborns.
The basic finding that firstborns have higher IQ scores has itself been disputed. One group of researchers examined data from the National Longitudinal Survey of Youth (NLSY) (USA), which gave them the opportunity to look at a large randomly selected sample of US families. The sample included children whose academic performance had been reviewed multiple times throughout their academic careers. This study found no relationship between birth order and intelligence. Recent studies of eldest children by both the Harvard Medical Journal (Aug. 2009) and a thesis published by Swedish research scientist Lars Orstenberg (see 'Younger Children, Brighter Futures', May 2009, Bazar Förlag Press) suggested that past research focuses too heavily on early life. Both papers point to a distinctly higher rate of success among second borns later in life in the areas of career as well as wealth.
Sexuality
The fraternal birth orderFraternal birth order
A correlation between fraternal birth order and male sexual orientation has been suggested by research. Ray Blanchard identified the association and referred to it as the fraternal birth order effect. The observation is that the more older brothers a man has, the greater the probability is that he...
effect is the name given to the observation that the more older brothers a man has, the greater the probability is that he will have a homosexual orientation. The fraternal birth order effect is the strongest known predictor of sexual orientation, with each older brother increasing a man's odds of being gay by approximately 33%. Even so, the fraternal birth order effect only accounts for a maximum of one seventh of the prevalence of homosexuality in men. There seems to be no effect on sexual orientation in women, and no effect of the number of older sisters.
In the book Homosexuality, Birth Order, and Evolution: Toward an Equilibrium Reproductive Economics of Homosexuality, Edward M. Miller suggests that the birth order effect on homosexuality may be a by-product of an evolved mechanism that shifts personality away from heterosexuality in laterborn sons. This would have the consequence of reducing the probability of these sons engaging in unproductive competition with each other. Evolution may have favored biological mechanisms prompting human parents to exert affirmative pressure toward heterosexual behavior in earlier-born children: As more children in a family survive infancy and early childhood, the continued existence of the parents' gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
line becomes more assured (cf. the pressure on newly-wed European aristocrats, especially young brides, to produce "an heir and a spare"), and the benefits of encouraging heterosexuality weigh less strongly against
Diminishing returns
In economics, diminishing returns is the decrease in the marginal output of a production process as the amount of a single factor of production is increased, while the amounts of all other factors of production stay constant.The law of diminishing returns In economics, diminishing returns (also...
the risk of psychological damage that a strongly heteronormative environment poses to a child predisposed toward homosexuality.
See also
- FamilyFamilyIn human context, a family is a group of people affiliated by consanguinity, affinity, or co-residence. In most societies it is the principal institution for the socialization of children...
- Only childOnly childAn only child is a person with no siblings, either biological or adopted. In a family with multiple offspring, first-borns, may be briefly considered only children and have a similar early family environment, but the term only child is generally applied only to those individuals who never have...
- Sibling rivalrySibling rivalrySibling rivalry is a type of competition or animosity among children, blood-related or not.Siblings generally spend more time together during childhood than they do with parents. The sibling bond is often complicated and is influenced by factors such as parental treatment, birth order, personality,...
- Individual PsychologyIndividual psychologyIndividual psychology is a term used specifically to refer to the psychological method or science founded by the Viennese psychiatrist Alfred Adler...
- Alfred AdlerAlfred AdlerAlfred Adler was an Austrian medical doctor, psychotherapist, and founder of the school of individual psychology. In collaboration with Sigmund Freud and a small group of Freud's colleagues, Adler was among the co-founders of the psychoanalytic movement as a core member of the Vienna...
- AdlerianAdlerianPertaining to the theory and practice of Alfred Adler , whose school of psychoanalysis is called Individual Psychology . Central to the Adlerian approach is to see the personality as a whole and not as the mere net result of component forces. Thus the term individual psychology...