Let’s face it: some of us are smarter than others. But is it because of nature or nurture?Many scientific studies have been conducted to determine the cause of high IQs, and a lot of it boils down to genetics. According to researchers, psychologists and scientists, personal beliefs and physical appearance can also indicate intelligence.
We pulled research from Fox News, CBS, Psychology Today, The Times and more to bring you 20 scientifically-proven signs you’re smart. Keep in mind, correlation does not always equal causation!
According to Psychology Today, people who use more drugs are more intelligent. 'Intelligent people don't always do the right thing,' they write, 'only the evolutionarily novel thing.'
According to a study conducted by National Child Development, 'more intelligent children in the United Kingdom are more likely to grow up to consume psychoactive drugs than less intelligent children.' These drugs include marijuana, cocaine, heroin, alcohol and tobacco.
The chart on the left shows the findings of the study. It depicts the latent factor for the consumption of 13 different kinds of psychoactive drugs, (cannabis, ecstasy, amphetamines, LSD, amyl nitrate, magic mushrooms, cocaine, temazepan, semeron, ketamine, crack, heroin, and methadone). There is a clear association between childhood general intelligence and adult drug consumption.
'Very bright individuals (with IQs above 125) are roughly three-tenths of a standard deviation more likely to consume psychoactive drugs than very dull individuals,' says Psychology Today. They ran the same study in the U.S. and found similar results.
If you attended Rally For Sanity, you're probably in good shape.
According to evolutionary psychologist Satoshi Kanazawa at the the London School of Economics and Political Science, people who have liberal political views have higher IQs.
Here is the reasoning: Liberal beliefs go against humans' evolutionary beliefs. In other words, being liberal would not have benefited our ancestors.
'The adoption of some evolutionarily novel ideas makes some sense in terms of moving the species forward,' CNN quotes George Washington University leadership professor James Bailey, who was not involved in the study. 'It also makes perfect sense that more intelligent people -- people with, sort of, more intellectual firepower -- are likely to be the ones to do that.'
CNN writes, 'These preferences may stem from a desire to show superiority or elitism, which also has to do with IQ. In fact, aligning oneself with 'unconventional' philosophies such as liberalism or atheism may be ways to communicate to everyone that you're pretty smart.'
Again, this has to do with defying common ancestral tendencies. Everyone knows guys are tempted to sleep around; it's biologically ingrained in them to 'spread their seeds.'
Those who resist the urge and are committed to one sexual partner, then, are actually smarter. They're thinking and acting out against historical human ways, which is a sign of intelligence.
This finding came from the same study that concludes liberals are smarter than conservatives.
The same is not true of females; being monogamous does not deem them more intelligent. 'This makes sense, because having one partner has always been advantageous to women, even thousands of years ago, meaning exclusivity is not a 'new' preference,' CNN writes.
Like the prior two slides, believing in God has been historically advantageous to humans. Challenging an ancient mindset is a sign of intelligence.
Evolutionary psychologist Satoshi Kanazawa found atheism is linked to higher IQs.
According to Reuters, 'Researchers found that among 121 Canadian children between the ages of 3 and 7, those whose mothers had suffered morning sickness scored higher, on average, on certain tests of IQ, memory and language skills.'
Lead researcher Dr. Irena Nulman of the Hospital for Sick Children in Toronto tells Reuters, 'The findings suggest that nausea and vomiting in pregnancy is not harmful and in fact may enhance favourably children's long-term.'
Researchers at the University of North Carolina at Chapel Hill found that female and male adolescents with an IQ score below 70 or above 110 are more likely to be virgins.
The Penn State Collegiate reports the findings:
'Adolescents with IQ scores ranging from 70 to 110 had the lowest probability of virginity, according to two researchers from the University of North Carolina at Chapel Hill. The average IQ score is 90 to 110.
'Mariah Mantsun Cheng, a research associate, and J. Richard Udry, professor of maternal and child health and sociology, both from the University of North Carolina at Chapel Hill, conducted the study. They discovered that 39.8 per cent of boys with an average IQ score have had sex while 29.2 per cent of boys with an IQ above 110 have had sex.
'They also found that 63.3 per cent of adolescent men and 81.6 per cent of women with IQ scores below average have never had sex and most have had fewer experiences of romantic attraction.'
'According to the research, an adolescent with an IQ score of 100 was 1.5 to 5 times more likely to have had intercourse than an adolescent with an above average score of about 120 to 130.'
Numerous studies on identical twins (who have the same genes) versus fraternal twins (who share, on average, half their genes) prove that intelligence is inherited.
NewScientist.com writes the findings of one study, 'Genes have a very strong influence over how certain parts of our brains develop, scientists in the US and Finland have found. And the parts most influenced are those that govern our cognitive ability. In short, you inherit your IQ.'
Apparently, the U.S. loses $8.7 billion every year thanks to IQs lowered by mercury exposure.
CBS writes, 'The Mount Sinai centre for Children's Health and the Environment combined a number of previous studies to determine hundreds of thousands of babies are born every year with lower IQ associated with mercury exposure.
'Using work examining the effects of lead exposure on IQ, researchers determined that even a 1.6 point drop in IQ could cost a person $31,800 in lifetime earnings because of missed educational opportunities or jobs...Lower IQ levels linked to mercury exposure in the womb costs the United States $8.7 billion a year in lost earnings potential.'
DailyMail reports, 'Young people who smoke regularly are likely to have markedly lower intelligence levels than those who do not smoke, and, according to the study of 20,000 young adults, the heavier the smoker, the lower the IQ.
'Those who smoke a pack or more of cigarettes a day averaged an IQ seven and a half points lower than that of those who do not smoke...Those who smoked more than a pack a day had particularly low IQs of around 90. An average intelligence IQ score ranges from 84 to 116 points.'
According to ScienceDaily.com, 'In two studies of breast-fed infants involving more than 3,000 children in Britain and New Zealand, breastfeeding was found to raise intelligence an average of nearly 7 IQ points if the children had a particular version of a gene called FADS2.'
Psychcentral.com reports, 'There is growing evidence that musicians have structurally and functionally different brains compared with non-musicians.
'In particular, the areas of the brain used to process music are larger or more active in musicians. Even just starting to learn a musical instrument can change the neurophysiology of the brain.'
In addition to boosting your IQ, musical training also helps your mood, memory, and ability to learn languages.
This concept goes back to the evolution idea. In the past, it benefited our ancestors to do things during the day and seek shelter at night. Going against this historical trend is a sign of intelligence. Studies also back up this theory.
Yahoo News reports, 'Sleep researchers tend to divide people into two groups, explains zoologist Robert Alison in the Winnipeg Free Press, based on whether they exhibit 'morningness' or 'eveningness.' A recent study claims that eveningness is an evolutionary advancement that marks out 'more intelligent individuals,' while those with lower IQs tend to restrict their activities primarily to daytime.'
Studies have shown that light-eyed people are more intelligent than dark. Don't worry if you have brown eyes, you have your own set of strengths.
Fox News reports, 'Light-eyed individuals and even light-eyed animals perform better at behaviours requiring delay, self-pacing, or non-reactors, while dark-eyed individuals and animals perform better at behaviours requiring speed, sensitivity or reactivity, according to a paper authored by University of Louisville professor emeritus Joanne Rowe.'
We're not sure how you're supposed to know if you have a big brain, but apparently people who have this attribute are smarter than those who don't.
Michael McDanielle of Virginia Commonwealth University conducted research on this topic. Here are his findings:
'The relationship between brain volume and intelligence has been a topic of a scientific debate since at least the 1830s. To address the debate, a meta-analysis of the relationship between in vivo brain volume and intelligence was conducted. Based on 37 samples across 1530 people, the population correlation was estimated at 0.33. The correlation is higher for females than males. It is also higher for adults than children. For all age and sex groups, it is clear that brain volume is positively correlated with intelligence.'
Reuters reports, 'An online survey of 895 Web users and experts found more than three-quarters believe the Internet will make people smarter in the next 10 years, according to results released on Friday.
'But 21 per cent said the Internet would have the opposite effect and could even lower the IQs of some who use it a lot.'
Time will tell, but most experts believe the internet benefits intelligence.
It's not that overweight people are born with lower IQs. Rather, obesity seems to have a negative effect overtime. The Telegraph reports one study's findings based on a series of memory tests:
'The new five-year study of more than 2,200 adults claims to have found a link between obesity and the decline in a person's cognitive function. The research, conducted by French scientists, involved men and women aged between 32 and 62 taking four mental ability tests that were then repeated five years later.
'The researchers found that people with a Body Mass Index -- a measure of body fat -- of 20 or less could recall 56 per cent of words in a vocabulary test, while those who were obese, with a BMI of 30 or higher, could remember only 44 per cent.
'The fatter subjects also showed a higher rate of cognitive decline when they were retested five years later: their recall dropped to 37.5 per cent, whereas those with a healthy weight retained their level of recall.'
Business Insider Emails & Alerts
Site highlights each day to your inbox.