Science

Evolution Didn’t Hardwire Us to Deal with Math, Scientist Argues

by Yasmin Tayag
Flickr / 401(K) 2013

Numbers rule everything around us. Whether you’re calculating the odds that President Trump will be impeached or analyzing whether the Golden State Warriors will actually win the NBA finals, consulting hard, quantifiable data before making a decision is our go-to behavior. And, being the only means by which we can make rational decisions, doing so is a very good instinct.

But that doesn’t mean it comes naturally to us.

While we take it for granted that modern human society is a society of numbers, University of California-San Diego cognitive scientist Rafael Nuñez, Ph.D., argues that evolution didn’t wire us to be that way. Despite the fact that other sentient members on the evolutionary tree show signs of being able to process numbers — Alex the African grey parrot famously counted numbers, and, a century before him, Hans the Horse made a killing counting for audiences — Nuñez argues that the natural capacity for numbers and arithmetic isn’t biologically preordained. Rather, he argues in his new article in Trends in Cognitive Sciences, it’s a result of a cultural mental framework that’s been foisted onto humanity.

“Numerical cognition,” he said in a statement on Wednesday, “is not biologically endowed.”

His opinion is [a controversial one](https://goo.gl/zTw9Zb). Many scientists are convinced by the existing evidence from animals and human babies that our brains actually are wired to handle numbers and math, much as it’s been shown that we (and our animal relatives) are predisposed to invent and use language to communicate. Three-day-old chickens, for example, were described as “proto-arithmetic” in 2009 after they displayed an innate ability to discern between small and large collections of objects and knew instinctively that the larger collection was better. Similarly, in 1987 chimpanzees were shown to not only be able to count but reliably add together two quantities of chocolates and determine which was the largest sum. While this may seem like compelling evidence that evolution has equipped the animal kingdom to do math, Nuñez stands by his assertion that processing numbers is a uniquely human and purely cultural phenomenon.

His argument rests on the crucial difference between actually doing math and being able to tell the difference between relative numbers of objects. All of those “counting” animals may be able to tell the difference between a pile of five seeds versus a pile of fifty, sure. But can these animals grasp the concept of the number 50 when those seeds are gone, and hold it in their minds so that it can be added to, subtracted, multiplied, or divided? Nuñez argues that the ability to think in a “quantical” way rather than a “numerical” way is unique to humans because of the influence of culture — and not all humans have it, because not all cultures value it.

Citing evidence that humans in non-industrialized nations don’t use exact numbers but rather relative quantities in their day-to-day dealings, Nuñez argues that the human ability to think quantically is the result of a culture that prioritizes that kind of thinking. Nuñez points at human hunter-gatherers to illustrate: Looking at a study of 193 hunter-gather languages, he found that most of them don’t have words for values over the number five, suggesting that those societies shrug at numerical precision because relative numbers are good enough. He argues that the brain doesn’t even have a specialized region for numerical processing, citing evidence from brain scans that the brains of Chinese and English speakers don’t light up in the same ways when they’re processing Arabic numbers.

If Nuñez is right (and the field is far from determining once and for all whether he is), his argument could call into question the other capabilities we consider to be hardwired into our brains, like the ability to make music, appreciate art, and, yes, even use language. If they’re not hardwired by evolution, then that means they’re not part of humanity’s default settings, which means they can. His argument raises a lot of questions that only further research will address.

In the meantime, what he seems most annoyed about is the idea that his colleagues keep using the argument that “it’s hardwired!” to describe abilities that nature has no precedent for — and therefore could not have evolved to address. “A circus seal may jump through a burning ring but it doesn’t tell us anything about the animal’s ability to deal with fire in its natural environment,” he said.

Related Tags