Birth order
From Freepedia
Birth order refers to the place of a child's birth in the family. Children are either "first born" or "later borns".
The influence of birth order is still an open issue, but some clear patterns have been established.
For males the number of older brothers (born to the same mother) increases the chances of homosexuality. With each older brother a male's chances of being a homosexual increases by about 30% relative to a first born male. The developmental mechanisms of this phenomenon are unknown, but it is theorized that immunological responses to subsequent male fetuses by the mother's body may affect certain neurological masculinizing effects of testosterone. No such correlation between birth order and female homosexuality exists.
Personality too is clearly and strongly influenced by birth order. Personality psychologists largely (though by no means without debate) agree that the Big five personality traits (aka Five Factor) represent something like a natural taxonomy of human personality variables. Cross-linguistically the vast majority of adjectives used to describe human personality fit into one of the following five areas, easily remembered by the acronym OCEAN: Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism.
In his book "Born to rebel", and in ongoing research papers, Frank J. Sulloway has mounted conclusive evidence that birth order effects on the Big Five are strong and very consistent. Using a scale between bipolar adjective pairs (ex.: hard-working . . . . . . . lazy) and intrafamily ratings with tens of thousands of respondents Sulloway has shown firstborns to be more conscientious, more socially dominant, less agreeable, and less open to new ideas compared to laterborns. In a cross-cultural replication of Sulloway's work anthropologist Paul Roach collected several hundred within-family ratings among horticulturalist Shuar Indians in Ecuadorian Amazonia and found nearly identical correlations between the Big Five and birth order among these nonwesternized people (conference presentation: HBES, 2002, Rutgers University).
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Birth order and intelligence
Birth Order and Intelligence: A Classic Study
In 1973 Lillian Belmont and Francis Marolla published family size, birth order and intelligence test (Dutch version of the Raven Progressive Matrices) data from nearly the entire population of 19 year-old Dutch men (386, 114 subjects). Their study design was complex, so interested readers should consult the primary source. However, a general overview of the results will be presented here. Belmont and Marolla found:
"Children from large families tend to make poorer showings on intelligence tests and on educational measures, even when social class is controlled." "Within each family size (i) firstborns always scored better on the Raven than did later borns; and (ii) with few inconsistencies, there was a gradient of declining scores with rising birth order, so that firstborns scored better than secondborns, who in turn scored better than thirdborns, and so forth." "In general, as family size increased, there was a decrease in Raven performance within any particular birth order position." For example, a thirdborn born child from a 3-child family would be expected to score higher than a thirdborn child from a 4-child family. A thirdborn child from a 5-child family would be expected to score even lower, and so on.
Why Might Birth Order Affect IQ?
In 1874 Francis Galton offered several reasons why birth order might affect eminence. Among them, he listed:
Primogeniture laws. Firstborn sons would be more likely have the financial resources to continue their education. Firstborns had the advantage of being "treated more as companions by parents." This means that they also undertake more responsibility than their younger siblings. Firstborn children would get more attention and better nourishment in families with limited financial resources
Birth order and personality
Many claim that birth order influences personality. The realm of pop psychology often attributes the following traits to each order:
First-born
The first-born child will receive the expectations of his parents. Because of this, many first-borns are in danger of acquiring perfectionistic or people-pleasing behaviors. On a more optimistic note, proponents of birth-order theory state that first-borns tend to be quite confident, diligent and mature. Not all first-borns are over-achievers, but even the most laid-back first-born is clearly guided by a need to do the right thing and strives to make a difference in his niche.
Middle-born
Middle-born children have a diverse range of personalities. The habits of many middle-borns however are motivated by the fact that they have never been truly in the spotlight--the first-born seemed to always be achieving, pioneering ahead and the younger sibling was secure in his niche as the entertainer of the family. They may develop great social skills and have an easier time growing up with an other-centered point of view..
The Baby
The name given to the youngest child is revealing: the youngest child of the family is viewed as the party animal, the entertainer who is unafraid to test his luck. While this certainly is not true of all younger siblings, proponents of the theory state that the baby of the family is an endearing, delightful friend if not too self-centered.
References
- Belmont, M., & Marolla, F.A. (1973). Birth order, family size, and intelligence. Science 182: 1096–1101.
External Links
- Birth Order chart
- "Second Son, Middle Child, Next Comes a Girl" a sonnet by Michael J. Farrand.
