A Dutch study shows that firstborn children are more intelligent than their younger siblings.
The scientists found that the oldest sibling is more likely to have much higher IQ than the youngest sibling.
Reserchers from Vrije University, Amsterdam, studied 650 children and tested their IQs three times until they were 18. The study shows a birth-order effect on intelligence in each of the tests.
Lead author, Dorret Boomsma, said, "The effect is seen in boys and girls."
Adding further he said, "The highest IQ scores were in children without any older siblings, followed by children with one older sibling.
"Children with two or more older siblings obtained the lowest score."
The exact reason why this happens is still not know but the most common reason could be the way in which they are raised, not genetics or otherwise. The first-borns have the benefit of individual monitoring by their parents and thus it boosts their intellectual development.
The findings will be published in the journal Intelligence.
If you are the youngest in the family then don't get depressed, as another study of 2,000 families, by the University of California showed that the last-borns are warmer, extrovert, creative and no doubt most favored. In addition, the middle-borns are open to new experiences, rebellious, less religious, and impulsive.
The first-ones are achievers, who are dominant, religious, conscientious and neurotic.
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