Full question: “If we evolved from monkeys into humans, are we eventually going to evolve into something so smart that humans look as dumb as apes?”
Charles Darwin outlined three things necessary for evolutionary change to occur: members of a species must differ in their characteristics (some of us are tall, some short); these characteristics must be hereditary (parents can pass them to their children); and some individuals have more children than others. So, if all the tall people in the world had more kids than the short people, the human race’s average height would go up an inch or two. Evolution is not a march towards improvement, as suggested by the ‘March of Progress’ picture, because there is no way of knowing exactly what sort of challenges the future will present. Our smart brains may have evolved because it indicated good health (it takes a lot of energy to keep our brains running, so having a large brain means being healthier and having access to good nutrition).
So how are we shaping up, brain-wise? Some studies say we’re getting smarter, others not. When you compare IQ scores of modern humans versus previous generations, you find that overall we score better than our ancestors. This has been called the Flynn Effect. Scientists have been exploring reasons for this. It could be anything from better access to education to improvements in health and nutrition in babies and young children (most likely a combination of these things). However, not only does the Flynn Effect appear to be tapering off, but it seems to be caused by changes in our lifestyle, education and standard of living rather than something in our genes.
But what if we’re actually getting less intelligent? Some scientists think that our ancestors were actually smarter than us because it took more intelligence to survive in a hunter-gatherer society, where outsmarting your prey and other predators meant the difference between life and death. There’s a chance that the genes that allowed us to become so smart won’t get passed on in the same way as in the past, because they’re not as important to our survival anymore. But anyone who has a “smartphone” could argue that we need to be even more intelligent to use our modern gadgets.
In the end, whether we become smarter as a species depends on what will allow us to thrive in our future environment. If survival depends on us gaining greater intelligence, then humans certainly may evolve to become smarter. Or we might reach an upper limit in intelligence beyond which we simply can’t go. So if we want humanity to be more intelligent in the future, let’s make smart the new sexy, and pass those brainy genes on to our kids.
Answer by Shambralyn Baker
Question from Zoe via website
Image: M. Garde via Wikimedia
References / More:
Our Fragile Intellect by Dr. Crabtree
BLAIR, C., GAMSON, D., THORNE, S., & BAKER, D. (2005). Rising mean IQ: Cognitive demand of mathematics education for young children, population exposure to formal schooling, and the neurobiology of the prefrontal cortex Intelligence, 33 (1), 93-106 DOI: 10.1016/j.intell.2004.07.008