Were the Victorians smarter than us?
The reign of Queen Victoria, from 1837 to 1901, coincided with countless scientific and industrial breakthroughs, from the first transatlantic telegraph to the publication of Charles Darwin's On the Origin of Species.
A team of European researchers now say they can explain this burst of innovation: people back then were "cleverer" than us.
A study published in the journal Intelligence purports that IQ has dropped 1.23 points per decade since Victorian times, or 14 points total.
If that seems sketchy, don't worry: this study is sure to be debated among scientists, too.
The research team behind the paper, four psychology professors from Sweden, Belgium, The Netherlands and Ireland, used reaction time to gauge IQ throughout the ages. Their theory: whereas more intelligent people used to have more offspring and less-intelligent people fewer, in the modern era that trend has been reversed, so overall IQ must be falling.
Because standardized tests for intelligence have changed over time, they can't be used to compare IQ now and IQ a hundred years ago. Instead, the researchers looked at reaction time tests, which measure how quickly a person responds to sensory stimuli. Reaction time seems to be associated with intelligence.Francis Galton, a Victorian polymath who was the one of the first to try to study genius, did tests of reaction time between 1884 and 1893. His tests of 2,522 males aged 18 to 30 and 888 females showed that mean reaction time was 183 to 187 milliseconds. Other studies in 1910, according to the Intelligence paper, found a mean reaction time of 192 milliseconds.
Twelve modern reaction time studies, however, found a mean of 250 milliseconds for males and 277 milliseconds for females. The researchers' conclusion: reaction time, and intelligence, is falling.
The authors of the Intelligence study did not test the modern-day subjects' reaction times and IQs themselves -- they compiled other studies into a meta-analysis. So the paper doesn't give information on how Galton tested his subjects versus how modern-day scientists test theirs.
So, were Galton's reaction time tests simply less accurate?
Another funny thing about this study is that it flies in the face of another much-debated theory about how IQ changes over time -- The Flynn Effect -- which says that IQ has climbed by an average of 3 points per decade since World War II.
And, as Discovery News points out, another study in the same issue of Intelligence says that IQ in Saudi Arabia has increased steadily over the last 40 years.
This study: cold hard truth? Silly conversation starter? Read it, decide for yourself, and maybe sharpen that IQ a little.
Kate Allen is the Star's science and technology reporter. Find her on Twitter at @katecallen.