It’s tempting to think of ourselves as smarter than people in generations past. And why not? We have smart phones (although, I’ll be the first to admit, my phone is smarter than me), smart TVs and smart cars are on the way. But does the invention and proliferation of new gadgets and devices mean our intelligence is increasing?
The theory of evolution would say yes. Why? Because the theory says evolution works through natural selection (to be clear: I believe natural selection is real, but not evolution). From an evolutionary viewpoint, it makes sense that the smartest humans would have an advantage over less smart humans (natural selection) and over time the human race would get smarter (evolution). Right?
Unless it doesn’t happen that way. What if our DNA is not becoming better as evolution would state, but instead is accumulating more and more mutations? In fact, some studies show each child inherits between 30-50 new mutations from his/her parents (most of these mutations are harmful or neutral). These add up over the generations.
Another study, completed by scientists from Sweden, the Netherlands and Ireland and published in the journal Intelligence, reaches the conclusion that human intelligence is decreasing. The scientists analyzed the results of 14 studies conducted between 1889 and 2004 that measured visual reaction time, which they believe is strongly correlated with general intelligence. Their conclusion is startling. According to these researchers, human intelligence (IQ) has declined at a rate of 1.16 points per decade or 13.35 points since the late 1800’s.
Why then do we feel so much smarter than our ancestors who used to live in caves, without so much as an IPod for entertainment? It’s not like these devices make us smarter (despite my son’s claims). In fact, we can look up all kinds of stuff people used to have to memorize, kind of like borrowing from a collective intelligence. Which leads me to think the amazing innovations and inventions of today are more likely due to the accumulation of knowledge, rather than an increase in our intelligence.
What do you think? Is human intelligence decreasing? With so much individual variation, can we even measure that as a species? Does it matter if we’re getting smarter or not?
References: “Rise and Fall of Human Intelligence,” Answers, Oct-Dec 2013, 8(4), p. 11, and https://answersingenesis.org/theory-of-evolution/molecular-clock/molecular-clock-off-line/Photo Credit: ID 18932264 © Hubis | Dreamstime.com