Well, I’m the exception on the rule I suppose:

The eldest children in families tend to develop higher I.Q.’s than their siblings, researchers are reporting today, in a large study that could settle more than a half-century of scientific debate about the relationship between I.Q. and birth order.

The average difference in I.Q. was slight — three points higher in the eldest child than in the closest sibling — but significant, the researchers said. And they said the results made it clear that it was due to family dynamics, not to biological factors like prenatal environment.

Researchers have long had evidence that firstborns tended to be more dutiful and cautious than their siblings, and some previous studies found significant I.Q. differences. But critics said those reports were not conclusive, because they did not take into account the vast differences in upbringing among families.

Three points on an I.Q. test may not sound like much. But experts say it can be a tipping point for some people — the difference between a high B average and a low A, for instance. That, in turn, can have a cumulative effect that could mean the difference between admission to an elite private liberal-arts college and a less exclusive public one.

Strangely, up until a certain age - 12 years - the younger siblings are more intelligent than their elderls. After this age, however, the situation changes. The question is why? Why are the oldest more intelligent - on average - than the youngest siblings?

One possibility, proposed by the psychologist Robert Zajonc, is that older siblings consolidate and organize their knowledge in their natural roles as tutors to junior. These lessons, in short, benefit the teacher more than the student.

Another potential explanation concerns how siblings find a niche in the family. Some studies find that both the older and younger siblings tend to describe the firstborn as more disciplined, responsible, high-achieving. Studies suggest — and parents know from experience — that to distinguish themselves, younger siblings often develop other skills, like social charm, a good curveball, mastery of the electric bass, acting skills.

If we just ignore the IQ part, I do recognize myself in the description of the youngest one(s):

This kind of experimentation might explain evidence that younger siblings often live more adventurous lives than their older brother or sister. They are more likely to participate in dangerous sports than eldest children, and more likely to travel to exotic places, studies find. They tend to be less conventional than firstborns, and some of the most provocative and influential figures in science spent their childhoods in the shadow of an older brother or sister (or two or three or four).

If I look at my own situation, I think that my sister was not very disciplined and did not value academic achievements much. In other words; I could distinguish myself from her, by doing well at school. She is more ‘homely’ and stable than I am though: she is perfectly happy taking care of the children, not living / traveling abroad, etc. I am the one who wants to travel, I am far more adventurous. Compared to my sister, I am also less stable - I constantly need something new, if I do not I get incredibly unhappy.

Furthermore - her strongpoint has always been that she is very social with people - people often call me charming, but she is the one people like. She is the compassionate and helpful one of the two. People often say that she is pure goodness (something of which no one has ever accused me of). She is the generous one, I am the greedy one. She is the compassionate one, I am the ‘tough’ and selfish one. She is the one who walks away from fights, I am the one who is looking for a fight every now and then. She is social one, I am the overly confident / arrogant one. On the other hand, I am a bit the clown of the family; entertaining everyone, making jokes and making a fool out of myself.

Lastly, I’d say, my goals are unconventional. From quite an early age, I was telling everyone who wanted to hear it that I would move to America, be successful there, marry a foreign woman, etc. My sister never said anything like that - she is happy where she is and wherever it is life will take her. She has never felt the drive to accomplish something ‘extraordinarily,’ I have always felt that I should do something that would distinguish me from the masses.

What are your thoughts on the article at the Times? Do you recognize your own situation in it?