Why aren't we smarter already? Evolutionary limits on cognition

[Tank]

Why aren't we smarter already? Evolutionary limits on cognition

(Medical Xpress) -- We put a lot of energy into improving our memory, intelligence, and attention. There are even drugs that make us sharper, such as Ritalin and caffeine. But maybe smarter isn't really all that better. A new paper published in Current Directions in Psychological Science, a journal of the Association for Psychological Science, warns that there are limits on how smart humans can get, and any increases in thinking ability are likely to come with problems.

The authors looked to evolution to understand about why humans are only as smart as we are and not any smarter. "A lot of people are interested in drugs that can enhance cognition in various ways," says Thomas Hills of the University of Warwick, who cowrote the article with Ralph Hertwig of the University of Basel. "But it seems natural to ask, why aren't we smarter already?"

Tradeoffs are common in evolution. It might be nice to be eight feet tall, but most hearts couldn't handle getting blood up that high. So most humans top out under six feet. Just as there are evolutionary tradeoffs for physical traits, Hills says, there are tradeoffs for intelligence. A baby's brain size is thought to be limited by, among other things, the size of the mother's pelvis; bigger brains could mean more deaths in childbirth, and the pelvis can't change substantially without changing the way we stand and walk.

Drugs like Ritalin and amphetamines help people pay better attention. But they often only help people with lower baseline abilities; people who don't have trouble paying attention in the first place can actually perform worse when they take attention-enhancing drugs. That suggests there is some kind of upper limit to how much people can or should pay attention. "This makes sense if you think about a focused task like driving," Hills says, "where you have to pay attention, but to the right things—which may be changing all the time. If your attention is focused on a shiny billboard or changing the channel on the radio, you're going to have problems."

It may seem like a good thing to have a better memory, but people with excessively vivid memories have a difficult life. "Memory is a double-edged sword," Hills says. In post-traumatic stress disorder, for example, a person can't stop remembering some awful episode. "If something bad happens, you want to be able to forget it, to move on."

Even increasing general intelligence can cause problems. Hills and Hertwig cite a study of Ashkenazi Jews, who have an average IQ much higher than the general European population. This is apparently because of evolutionary selection for intelligence in the last 2,000 years. But, at the same time, Ashkenazi Jews have been plagued by inherited diseases like Tay-Sachs disease that affect the nervous system. It may be that the increase in brain power has caused an increase in disease.

Given all of these tradeoffs that emerge when you make people better at thinking, Hills says, it's unlikely that there will ever be a supermind. "If you have a specific task that requires more memory or more speed or more accuracy or whatever, then you could potentially take an enhancer that increases your capacity for that task," he says. "But it would be wrong to think that this is going to improve your abilities all across the board."

Some interesting speculations here. If there is a limit to human intelligence could that place a limit on our ability to understand and therefore describe reality?

[Too Few Lions]

yeah, I've always thought there's an optimum IQ for humans, and it's not necessarily all that high. Most jobs don't require all that high an intellect, and if you're highly intelligent, I think most jobs may end up boring you!

Plus socially I think you're better off being of average intelligence. You're going to find it easier to find similar people to socialise with or meet people of the opposite sex of similar intelligence or with similar interests. Plus most of human culture is aimed towards people of average intelligence in a capitalist society, as they're the biggest market offering the biggest profit.

I also think think you're more likely to ask awkward philosophical questions the smarter you are, and the answers you find may not make your life any easier or any happier. I'm not sure that being highly intelligent is an evolutionary advantage at all in human society, thus we may not evolve to be any smarter.

[xSilverPhinx]

I read something online once that posited that there is even a physical limitation for how smart our brains can get, in terms of how many connections and size, before it crosses a threshold and becomes less efficient.

Also, our technological extensions are evolving now, such as computers. I think transhumanism will solve all these deficits in cognition problems...

Edited to add:

Something along these lines, though this one is more about energy consumption. I couldn't find the original article which talked about actual networking and implications for speed and efficiency, hand-in-hand with the whole energy thing of course.

[The Magic Pudding]

I read something online once that posited that there is even a physical limitation for how smart our brains can get, in terms of how many connections and size, before it crosses a threshold and becomes less efficient.

Also, our technological extensions are evolving now, such as computers. I think transhumanism will solve all these deficit in cognition problems...

But will it be captured by a corporation.

[OldGit]

yeah, I've always thought there's an optimum IQ for humans, and it's not necessarily all that high. Most jobs don't require all that high an intellect, and if you're highly intelligent, I think most jobs may end up boring you!

Plus socially I think you're better off being of average intelligence. You're going to find it easier to find similar people to socialise with or meet people of the opposite sex of similar intelligence or with similar interests. Plus most of human culture is aimed towards people of average intelligence in a capitalist society, as they're the biggest market offering the biggest profit.

I also think think you're more likely to ask awkward philosophical questions the smarter you are, and the answers you find may not make your life any easier or any happier. I'm not sure that being highly intelligent is an evolutionary advantage at all in human society, thus we may not evolve to be any smarter.

I agree entirely.  Intelligence has got the race where we are now, which is   not in all ways an improvement on hunter-gathering.

[Pharaoh Cat]

Plus if our brains got larger, the skull would have to get larger, which probably makes the females among us wince, as they consider the threshold through which that skull must pass.

[DeterminedJuliet]

Also, being super smart doesn't necessarily get you laid more. Survival advantages are nice, but at the end of the day, you still have to get someone to do you for it to mean anything in an evolutionary sense.

[Tank]

Also, being super smart doesn't necessarily get you laid more. Survival advantages are nice, but at the end of the day, you still have to get someone to do you for it to mean anything in an evolutionary sense.

A point not lost on me as of my three kids my eldest daughter, the one with the lowest academic achievement (but highest Emotional Quotient) has produced my first grandchild. Yet my son, who is 3 years into his PhD will probably never have a kid as he's way too selfish. I think my younger daughter will have a couple of kids and she's upper level IQ with a 1st class honours.

[Sandra Craft]

Yet my son, who is 3 years into his PhD will probably never have a kid as he's way too selfish.

I wonder if they actually have a name for that, the Nerd Dilemma?  My stepmother used to teach intellectually gifted 5th graders and she told me once the biggest challenge was not keeping up with them mentally (tho that was hard enough) but dealing with them emotionally because they were so far behind other kids their age.

[hismikeness]

yeah, I've always thought there's an optimum IQ for humans, and it's not necessarily all that high. Most jobs don't require all that high an intellect, and if you're highly intelligent, I think most jobs may end up boring you!

Plus socially I think you're better off being of average intelligence. You're going to find it easier to find similar people to socialise with or meet people of the opposite sex of similar intelligence or with similar interests. Plus most of human culture is aimed towards people of average intelligence in a capitalist society, as they're the biggest market offering the biggest profit.

I also think think you're more likely to ask awkward philosophical questions the smarter you are, and the answers you find may not make your life any easier or any happier. I'm not sure that being highly intelligent is an evolutionary advantage at all in human society, thus we may not evolve to be any smarter.

This all could be true, as it seems to make sense, but with so many people it would seem that the average intelligence should stay relatively the same provided the birthdate remains about the same, but it appears to me that the people I'm around at least are getting dumber and dumber.

Average intelligence amongst the populace seems like it happens because it's so watered down, so to speak. There are so many people that they can't all be properly educated anymore... it's a sad state of affairs. Plus, and I have no studies to quote confirming this, but it seems the dumber of us tend to breed earlier and more often, thus perpetuating the Idiocracy like scenario. For those that haven't seen it, check it out. It's pretty funny.

Average intelligence... I think about it like this: picture a person you know who you consider to be of average intelligence and realize their's, on average, 3.5 billion people dumber than that.

[Jose AR]

This piece has a hidden assumption: that we (current humans) are smarter than humans of say, 5,000 or 50,000 years ago. This is a throwback to the victorian (and japanese?) idea of constant progress and improvement. A further, and deeper, hidden assumption is that we (humans) are 'more evolved' than 'lesser' animals.

Both assumptions are false and reveal the tragic level of our understanding of biology, evolution, and logic.

It is true that I know more (way more) than the average man from 25,000 years ago. But he knew lots of stuff too. He had language, fire, smelting, pottery, weaving, tanning, cooking, baking, milling, brewing, music, painting, jewelry, etc. There is no objective way to compare intelligence levels. (we can't even do that today among living people). We love the idea that we are advanced and have progressed since then. The truth is that we stand on the shoulders of giants, that occasionally someone invents fire or wireless communication, then we just copy it, never having to reinvent, or even understand it. Few people (not me) can derive the pythagorean theorum from scratch, but we all chant the 2500 year old incantation as if we could.

It is true that we seem smarter than most animals, but intelligence is the wrong measurement. The true measurement is fitness to succeed in an environment. Just like a poodle could not be released among wolves and survive becuase it is not smart enough, I could not be released among people of 25,000 years ago and survive because I am not smart enough. Sure I could do trigonometry, but I could not hunt, fish, gather food, or prepare and store it, or, in short, use the technology of the day to succeed. Some animals that, on the face of it, seem more evolved than us are certain bats, many hunting whales, and seals. Seals were fish that moved to land that move to the sea that moved back to land; that's a lot of evolution!

Are humans still evolving? of course, but we are not selecting for IQ (what ever that is). We are selecting for the ability to survive cross-species diseases, for the abilty to survive genetically modified food, and for (for men) the abilty to be socially adept enough to attract a mating female.

Intelligence is ephemeral and cultural, and to the degree that all humans show almost no variation in DNA, all humans have basically the same equipment. The most backward, creation believing, reason-eschewing person is as smart as me. That I grew up in a culture (family) that valued education and sent me to school and bought me books and taught me to question and reason and think, does not make me more intelligent. I am just as smart as a brain surgeon, he just went to brain surgery school and grew up believing in the possibility of brain surgery as a career.

But I cannot do brain surgery, and some people cannot think.

(If we start breeding for brains we better start breeding for wide hipped women first)

Jose AR

[DeterminedJuliet]

You have some good points, Jose AR, and I partly agree. We do tend to have a bias towards "social progression".

But I don't anyone here is really arguing that we've gotten all that much more intelligent, on an evolutionary scale, in the past 2000 years. 2000 years is really only 50 human life-times and that's nothing in an evolutionary sense. I think most people are referring to a much, much larger span (homo sapiens have been around, what? about 200,000 years? And then you have to account for the species that we evolved from before homo sapiens)

I'm not expert on evolution, but those are my thoughts on it.

[Stevil]

Sorry, just noticed someone has already highlighted the movie Idiocracy.

Why isn't there a delete post button.

[Jose AR]

OMG, Idiocracy is my favorite!

[xSilverPhinx]

I just thought i'd throw in a documentary on the Mind's Big Bang.

Between 100,000 and 50,000 years ago, something happened that triggered a creative, technological, and social explosion, that allowed humans to dominate the planet. What forces may have contributed to the emergence of the modern human mind?