“For some reason, there could be a selective passage of those traits from fathers to son, but biologically, we still do not know how this could work.” 
 
 She also says girls with older fathers may well be geeky too, just in different ways: “Another possibility is that we have not measured ‘geekiness’ in a way that allows to capture its manifestation in females—there remains a caveat that daughters of older men are just as geeky, but we could not capture it in the current study.” 
 
 The study, Janecka adds, does not mean men should put off having children until they are older in the hope of having more intelligent sons. Covariates in the adjusted models included socioeconomic status (SES; index of parent qualifications and employment, and mother’s age at birth of first child), maternal age at conception, sex and zygosity. Furthermore, to ensure that our results did not arise due to either very limited number of offspring of fathers in the highest paternal age categories (paternal age >51) or enrichment of autism cases among the offspring of older men, all analyses were also conducted in (i) a subset of children with fathers aged 50 or younger at conception, and (ii) after excluding individuals with a confirmed autism diagnosis. When the scientists looked at the children’s achievements at school they found that having a high IQ, a tendency to focus intensely and social aloofness were all linked to children taking more technical GCSEs. While there has been much research showing the negative impact having children later in life can have—including increased risk of autism and schizophrenia—little has been done into the potential benefits. The team then created the Geek Index by scoring the twins geeky traits, when they were 12, by looking at their: 
 
 non-verbal IQ 
 
 ability to focus on a subject 
 
 social aloofness 
 
 Those with a high geek score, unsurprisingly, went on to do better at school - particularly in the fields of science, technology, engineering and mathematics. Previous work by Janecka and others has found that children born to older men are more at risk of medical conditions including autism and schizophrenia. Another could be that men who get the chance to become fathers at a later age need to show “special positive skills.” 
 
 “This special skill may be genetic and transmitted to the offspring,” he says.
– A new study suggests an upside for boys who have older dads: higher IQs. More specifically, they tend to score higher on what the researchers call the "geek index," reports the Guardian. And this is clearly seen as a positive: "If you look at who does well in life right now, it’s geeks," says Magdalena Janecka at King’s College London. The geek index, she explains, is determined by such factors as ability to focus, non-verbal IQ scores taken at age 12, and social aloofness. The latter trait may sound like a negative, but the BBC frames it as the boys not being overly concerned with fitting in. A mother's age appears to have no impact. The team studied more than 7,000 sets of twins in the UK. The average geek score for boys born to dads 25 or younger is 39. It goes up to 41 when dads had the child between 35 and 44, and jumps to 47 when dads were 50 or older. The impact was less pronounced on girls, and more pronounced when measuring science, tech, engineering, and math scores. Kids born to fathers 50 or older were 32% more likely to earn at least two A's on standardized tests than children born to men aged under 25, the researchers report in Translational Psychiatry. They calculate that 57% of the geek index score is inherited, with possible overlap between genes that contribute to a high geek score and to autism. “Our primary hypothesis is that higher levels of those ‘geeky’ traits in offspring of older men are mainly due is due to characteristics of the fathers themselves," Janecka tells Newsweek. "Men who decide to delay fatherhood often do so due to their extended career and educational pursuits, and likely themselves display higher levels of ‘geekiness.’” (Younger fathers are also likelier to die younger.)