Sons of older fathers are more likely to display "geeky" traits such as high intelligence, obsessional interests, and not caring if they fit in, new research has shown.
Scientists came to the conclusion after studying the behaviour of 15,000 twin pairs from the UK.
When the boys were 12 years old they completed on-line tests that measured geek-like traits including a high non-verbal IQ, a strong focus on personal interests, and social aloofness.
Parents were also asked if their offspring cared about how they were perceived by their peers, and whether they had any hobbies that took up a lot of their time.
Using the results, the researchers compiled a "geek index" for every child. Overall, sons of older fathers turned out to have a higher geek index score than those born when their dads were younger. And geekiness appeared to "jump" after a father's 45th birthday.
However, being geeky was not necessarily a handicap and in some ways proved advantageous.
Several years after their scores were measured, geekier boys did better in school exams than their classmates, especially in Stem (science, technology, engineering and mathematics) subjects.
Lead scientist Dr Magdalena Janecka, from King's College London and The Seaver Autism Centre in New York City, said: "Our study suggests that there may be some benefits associated with having an older father.
"We have known for a while about the negative consequences of advanced paternal age, but now we have shown that these children may also go on to have better educational and career prospects."
Previous studies have linked older paternal age with a higher risk of autism and schizophrenia in children.
The research, published in the journal Translational Psychiatry, did not investigate the reasons why older men fathered geekier sons.
One possibility is that genetic variants for autism may also contribute to geekiness, and they are more likely to be present in older fathers.
Dr Janecka added: 'When the child is born only with some of those genes, they may be more likely to succeed in school. However, with a higher 'dose' of these genes, and when there are other contributing risk factors, they may end up with a higher predisposition for autism. This is supported by recent research showing that genes for autism are also linked with higher IQ."
Another factor could be the role of the home environment, the scientists believe. Children of older fathers with established careers and higher socio-economic status were more likely to find themselves in an enriched environment and have access to better schooling.