Intelligence is one of those hard-to-define qualities, which fall into the category of 'things you know when you see.' Fortunately, many attempts have been made to quantify intelligence, and we've begun to discover patterns, suggesting links between intelligence and certain characteristics. Here I will explain some of the surprising characteristics which have been found to exist more commonly in intelligent people. Since co-occurrence does not imply causation, the exact relationship between these things can be hard to judge. So don't get too big-headed just because you are a hairy, left-handed homosexual.

10.Left-handedness

The brain is split into two hemispheres. While each half of the brain does broadly the same thing as the other, there are some differences. In humans, and lots of other mammals, one side of the brain is slightly dominant – this is why you favor one hand over another. Some studies have shown that left-handedness is linked to intelligence; left-handed people tend to score higher on IQ tests, and can also often finish these tests faster than right-handed people. Other studies, however, have shown that left-handed people have a wider range of IQs – making them over-represented in both the highly intelligent and the rather dim-witted sections of the population.

9.Homosexuality

A study by the evolutionary psychologist Satoshi Kanazawa this year has found a small but significant link between homosexuality and intelligence. Rather than homosexuality itself being a characteristic of intelligence, Kanazawa's results suggested that those who had had multiple homosexual partners were more likely to be intelligent. Those who scored highest on intelligence tests, tended to have had the greatest number of homosexual partners. Kanazawa suggests that homosexuality may be a reflection of inquisitiveness – a sure precursor, or companion, to intelligence. It has been suggested that the positive effect of homosexuality towards intelligence may be caused by society's attitude towards gay people. Children bullied for perceived homosexuality may turn to intellectual pursuits, and may feel a greater urge to strive for achievement in areas where they will be accepted.

8.Birth order

Many studies have found a link between IQ and the order in which you were born in your family. Firstborn children were found to be generally more intelligent than their siblings; the further down each child sat on the pecking order, the worse they generally scored in IQ tests. It was unknown whether this effect was due to some change in pre-birth conditions as a mother continued to bear children, or whether it was a post-birth social effect. Recent studies have revealed that the main determinant for IQ is how children are treated within their family – as opposed to birth order in itself. In families where the first child dies, the surviving second child, on average, has the same boost in IQ as is usual for a first child.

7.Atheism

The link between IQ and religiosity has been studied extensively, in both individuals and societies. Average IQ scores tend to vary between countries. Those countries with the highest rates of atheism were found to be in the highest range of IQ scores. Since societal links can be easily skewed by other factors, studies on individuals have also been carried out. A 2008 study examined the relationship between intelligence and religious belief. When ranked in terms of intelligence, atheists generally came out on top, followed in order by agnostics, liberal believers, and last – and in this case least – religious fundamentalists.

6.Body hair

Studies on men by Dr Aikarakudy Alias have found a link between body hair and intelligence. Rather than looking at IQ, he looked the relationship between body hair and levels of education. Perhaps contrary to popular belief, he found that men who were students or graduates had more body hair than those who work menial jobs. He also found that students who excelled in their degree were often hairier than students who performed poorly.While his work focused particularly on chest hair, he also correlated the presence of back hair to intelligence in men. The hairiness of intelligent women has yet to be studied systematically.

翻译：王珂 来源：前十网