Selects: Is birth order important?
In this episode of Stuff You Should Know, Josh Clark and Chuck Bryant examine how birth order affects personality development within families. The hosts explore various theories about how firstborns often develop structured personalities due to intense parental attention, while younger siblings tend to be more free-spirited, and how these dynamics shift in blended and adoptive families.
The episode delves into the scientific research and ongoing debates about birth order effects, including studies on IQ differences between siblings and the challenges researchers face when studying this topic. The hosts also discuss Frank J. Sulloway's research on how later-born children approach established norms, and the "Fraternal Birth Order Effect" regarding birth order's relationship to sexual orientation in right-handed men.
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Theories and Beliefs Around Birth Order and Personality
In this episode, Chuck Bryant and Josh Clark explore how birth order might influence personality development through family dynamics and resource distribution.
Birth Order Effects on Personality
Birth order theory suggests that firstborns often develop conscientious and structured personalities due to intense early parental attention. The confluence theory supports this, noting that firstborns initially experience a more intellectually stimulating environment. In contrast, youngest children typically develop more free-spirited and attention-seeking traits, as Bryant notes they often experience more relaxed parenting with fewer rules.
In blended and adoptive families, these effects become more complex. Children under 5 tend to adapt their personalities to fit their new birth order position, while older children, particularly those around 12, may struggle to adjust to their new family structure.
Research and Debates on "Birth Order Effects"
The scientific community remains divided on birth order's impact. While some studies have found trait differences, such as increased neuroticism in middle children, others suggest minimal effects. A Norwegian study found a small 2.3 IQ point difference between first and second-born children, though the significance of this difference remains debatable.
Research faces significant challenges, including difficulty controlling for variables like socioeconomic status and family dynamics. Bryant and Clark note that birth order effects appear strongest when siblings are together, suggesting possible behavioral bias in family situations.
Birth Order and Personality Traits
Frank J. Sulloway's 1996 book "Born to Rebel" presents interesting findings about later-born children. His research showed that later-borns were 4.6 times more likely to support Darwinism between 1859-1875, suggesting they may be more inclined to challenge established norms.
The "Fraternal Birth Order Effect" research indicates that right-handed men's likelihood of being gay increases with each older brother. Scientists speculate this might be due to mothers developing stronger immune responses to male proteins with each successive pregnancy, potentially affecting fetal development.
1-Page Summary
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Clarifications
- In blended and adoptive families, birth order effects can be more complex. Younger children under 5 may adjust their personalities to fit their new position in the family hierarchy, while older children, especially around 12 years old, might find it challenging to adapt to the new family structure. These adjustments can influence how birth order impacts personality traits in these unique family dynamics.
- Frank J. Sulloway's research in "Born to Rebel" suggested that later-born children were more inclined to support Darwinism during a specific historical period. This finding implies that birth order may influence ideological beliefs and attitudes towards established norms. Sulloway's work proposed a link between birth order and a tendency to challenge prevailing ideas, showcasing a potential connection between family dynamics and intellectual development. This research sheds light on how birth order could play a role in shaping individuals' perspectives and contributions to societal discourse.
- The "Fraternal Birth Order Effect" is a phenomenon where the likelihood of a man being gay increases with each older biological brother he has. This effect suggests that there may be a relationship between male sexual orientation and the number of older brothers a man has. Scientists theorize that this phenomenon could be related to changes in the mother's immune response to male proteins during successive pregnancies, potentially influencing the sexual orientation of later-born sons.
Counterarguments
- Birth order theory is not universally accepted, and there is significant debate about its validity due to conflicting research findings.
- Personality development is complex and influenced by a multitude of factors beyond birth order, such as genetics, parenting style, culture, and life experiences.
- The intellectual environment for firstborns may not always be more stimulating, as this can vary greatly depending on individual family circumstances and resources.
- Not all youngest children develop free-spirited or attention-seeking traits; such generalizations may not account for individual differences and unique environmental influences.
- The adaptability of children under 5 in blended and adoptive families is not guaranteed and can be influenced by many factors, including the child's temperament and the family's approach to integration.
- Older children may not always struggle with adjustments in new family structures; some may adapt well or even thrive due to increased social support and opportunities.
- The 2.3 IQ point difference found in the Norwegian study is relatively small and may not have practical significance in real-world settings.
- The presence of siblings alone may not be the sole reason for observed birth order effects; these could also be due to parental expectations, cultural norms, or other uncontrolled variables.
- Sulloway's findings on later-born children and their propensity to challenge norms may not be directly caused by birth order but could be influenced by other factors such as social movements or personal experiences.
- The "Fraternal Birth Order Effect" is a correlation that does not necessarily imply causation, and the underlying mechanisms are still not fully understood.
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Theories and Beliefs Around Birth Order and Personality
Chuck Bryant and Josh Clark discuss the intriguing concept of birth order and its perceived effects on personality through various dynamics within families.
Birth Order Affects Personality Via Family Resource and Attention Dynamics
An individual's personality may be shaped to some extent by their birth order as it's believed to be linked with specific family resource and attention dynamics.
Firstborns: Conscientious, Structured, Achievement-Oriented Due to Early Parental Focus
According to birth order theory, firstborns often develop traits like being conscientious, structured, and reliable due to the intense focus and attention they receive from their parents. Firstborns might become perfectionists, favoring maturity as they often interact with adults, including their parents and their friends.
The confluence theory amplifies this idea, suggesting that firstborns are exposed to a more intellectually stimulating environment when they're the only child. However, this environment changes when the firstborn has to spend time with a less knowledgeable younger sibling.
Youngest Children: More Free-Spirited and Attention-Seeking due to Reduced Supervision and Expectations
Youngest children tend to be characterized as free-spirited, fun-loving, and attention-seeking. Chuck Bryant, drawing from his own experience, describes the youngest sibling as often having a more relaxed upbringing with fewer rules imposed compared to older siblings, possibly due to the parents being more preoccupied or simply more chill by that point in their parenting journey.
Blended and Adoptive Families Complicate Birth Order Effects as a Child's Position May Shift
In blended and adoptive families, the clearly defined roles suggested by birth order theory can become blurred, as a child’s position ma ...
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Theories and Beliefs Around Birth Order and Personality
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Counterarguments
- The idea that firstborns are more conscientious and structured is not universally supported; personality traits can be influenced by a multitude of factors beyond birth order, such as genetics, cultural background, and individual life experiences.
- The notion that firstborns become perfectionists due to early parental focus is an oversimplification; not all firstborns exhibit perfectionist tendencies, and such traits can develop due to a variety of reasons unrelated to birth order.
- The concept that firstborns are exposed to a more intellectually stimulating environment could be challenged by the fact that all children can access various forms of stimulation through education, social interactions, and technology, regardless of their birth order.
- Characterizing youngest children as free-spirited and attention-seeking may not account for individual differences and the diverse ways in which children of any birth order can express their personalities.
- The assertion that youngest children have a more relaxed upbringing with fewer rules may not hold true in all families, as parenting styles can change over time and are influenced by more than just the experience of having multiple children.
- The impact of blended and adoptive families on birth order effects is complex and can vary greatly; some children may not experience significa ...
Actionables
- You can create a personalized growth plan that leverages your birth order traits for career development. If you identify as a firstborn, focus on roles that value structure and reliability, such as project management. As a youngest child, consider careers that thrive on charisma and flexibility, like sales or creative industries. This way, you're using inherent tendencies to your advantage in a professional setting.
- Develop a family bonding activity that aligns with each child's birth order characteristics. For instance, set up a family book club where the firstborn can lead discussions, nurturing their conscientious nature, while the youngest might be responsible for choosing fun, engaging books or organizing creative storytelling sessions, catering to their free-spirited personality.
- If you're integrating a child into a new family structu ...
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Research and Debates on "Birth Order Effects"
Chuck Bryant and Josh Clark explore the contentious debate on whether a person's birth order influences their personality and behavior, an issue that splits the scientific community and presents significant research challenges.
Scientific Community Split On Birth Order's Impact on Personality and Behavior
Bryant and Clark note that scientists have yet to reach a consensus on the significance of birth order effects. While some studies have found trait differences, such as a tendency for middle children to exhibit more neuroticism, others see minimal to no effects.
Studies Find Trait Differences by Birth Order
Some research, including studies using the Big Five personality inventory, suggests trait differences based on birth order. For example, a study might link neuroticism more commonly with middle children. Additionally, a Norwegian study observed a 2.3 IQ point difference between first and second born children out of a large sample size of 241,000 subjects, leading to further speculation on whether such a slight difference is meaningful or not. But the skepticism about the validity of IQ tests and questions about meaningfulness pose significant doubts.
Minimal Birth Order Effects Compared To Other Personality Factors
Other factors like socioeconomic status, racial background, and gender have shown to be more significant in forming personality than birth order. Evidence suggests any birth order effects might be so small that they are effectively negligible in the broader scope of personality development.
Challenges Complicate Proving Birth Order Impact
Clark and Bryant emphasize the many difficulties associated with isolating birth order's impact due to a plethora of influencing factors.
Controlling For Complex Confounding Variables: Socioeconomic Status, Gender, Family Dynamics
It's challenging to control for complex variables such as socioeconomic status, gender, and family dynamics in research about birth order. Attempting to determine the birth order effects on personality of ...
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Research and Debates on "Birth Order Effects"
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Clarifications
- The Big Five personality inventory is a widely used model in psychology that categorizes personality traits into five main dimensions: openness, conscientiousness, extraversion, agreeableness, and neuroticism. Each dimension represents a spectrum of characteristics, and individuals can fall anywhere along these spectrums. This model helps researchers and psychologists understand and measure personality differences across individuals based on these five key traits.
- Confounding variables are external factors that can influence the relationship between the variables being studied, leading to misleading or incorrect conclusions. These variables are not the main focus of the study but can impact the results if not properly controlled for. Researchers need to identify and account for confounding variables to ensure the accuracy and validity of their findings.
- Demographic shifts typically refer to changes in the composition of a population over time, often influenced by factors like birth rates, death rates, migration patterns, and societal trends. These shifts can impact various aspects of society, such as workforce dynamics, resource allocation, and cultural norms. Understanding demographic shifts is crucial for policymakers, businesses, and researchers to anticipate and respond to evolving societal needs and chal ...
Counterarguments
- While some studies suggest minimal birth order effects, other research might argue that these effects are more pronounced in specific cultural or familial contexts that haven't been thoroughly studied.
- The 2.3 IQ point difference found in the Norwegian study could be argued to be statistically significant, especially when considering large populations, and might have implications for educational and social policies.
- The argument that socioeconomic status, racial background, and gender are more significant than birth order doesn't preclude the possibility that birth order could interact with these factors in complex ways to influence personality.
- The difficulty in controlling for variables doesn't necessarily mean that birth order has no effect; it could suggest that our current research methodologies need refinement to detect more subtle influences.
- Biases in self-reported measures and historical data are a challenge across many areas of psychological research, not just birth order studies, and methods to mitigate these biases ca ...
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Birth Order and Personality Traits
Chuck Bryant and Josh Clark discuss various theories and research findings that suggest birth order can influence personality traits and even sexual orientation.
Sulloway's Theory: Later-Born Children Support Scientific Revolutions
Frank J. Sulloway, in his 1996 book "Born to Rebel," posited that later-born children may be more likely to support scientific revolutions.
Later-Borns 4.6x Likelier Than Firstborns to Support Darwinism (1859-1875)
Sulloway conducted research on historical figures and found that later-born scientists were 4.6 times more likely than firstborns to support Darwinism in the period from 1859 to 1875.
Theory: Later-Borns Compelled to Challenge Norms
The reasoning behind Sulloway's findings suggests that later-borns may feel compelled to challenge norms and adopt outsider opinions due to their symbolic status as outsiders in their own families. They often compete with older siblings for attention and validation, potentially driving them towards revolutionary thinking.
"Fraternal Birth Order Effect" Suggests Increased Likelihood Of Being Gay With Each Successive Boy Born
Research known as the "Fraternal Birth Order Effect" indicates that a boy's chances of being gay increase with each older brother born before him.
Effect Limited To Right-Handed Men, Suggesting Biological Basis
A surprising aspect of this effect is that it's limited to right-handed men. No statistical difference in the incidence of homosexuality among left-handed men is observed, regardless of how many older brothers they have. This suggests the cause of the effect is biological, not social.
Speculation: Mother's Immune Response to Male Proteins Strengthens With Each Pregnancy
A proposed physiological explanation for ...
Here’s what you’ll find in our full summary
Birth Order and Personality Traits
Additional Materials
Clarifications
- Frank J. Sulloway's theory posits that later-born children are more inclined to support scientific revolutions due to their position in the family birth order. This theory suggests that later-borns, often competing with older siblings for attention, may be more open to challenging established norms and adopting unconventional viewpoints. Sulloway's research on historical figures found that later-born scientists were significantly more supportive of revolutionary ideas like Darwinism during specific time periods. This theory highlights the potential influence of birth order on an individual's predisposition towards embracing new and unconventional ideas in the realm of science and beyond.
- Frank J. Sulloway's research found that later-born scientists were 4.6 times more inclined to support Darwinism between 1859 and 1875 compared to firstborns. This suggests a correlation between birth order and the likelihood of embracing revolutionary scientific ideas during that specific historical period.
- Later-born children, who have older siblings, may feel a need to distinguish themselves within the family dynamic. This can lead them to challenge established norms and beliefs as a way to carve out their own identity. The competition for attention and validation within the family structure can push later-borns to adopt unconventional or rebellious viewpoints. This dynamic can contribute to a tendency for later-borns to question authority and embrace alternative perspectives.
- The "Fraternal Birth Order Effect" is a phenomenon where the likelihood of a ...
Counterarguments
- The correlation between birth order and support for scientific revolutions may be confounded by other variables such as the era's cultural, social, and economic conditions, which could also influence revolutionary thinking.
- The sample of historical figures studied by Sulloway might not be representative of the general population, and thus the findings may not be generalizable.
- The 4.6 times likelihood figure may be subject to interpretation and could vary with different methodologies or when considering different historical periods and contexts.
- The idea that later-borns inherently challenge norms due to symbolic outsider status is a broad generalization and may not account for individual differences or the influence of other factors such as parenting style, socioeconomic status, or education.
- The "Fraternal Birth Order Effect" has been observed in some studies, but it is not universally accepted, and other research has failed to replicate these findings, suggesting that the phenomenon may not be as robust as initially thought.
- The biological basis of the "Fraternal Birth Order Effect" is still a matter of speculation, and the ...
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