# The evolution of intelligence. **URL:** \ **Category:** Factual Questions\ **Created:** [September 13, 2008, 8:44pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481 "2008-09-13T20:44:15Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Charlie\_Tan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/charlie_tan/32/12582_2.png) [@Charlie\_Tan](https://boards.straightdope.com/u/Charlie_Tan)\ **Post date:** [September 15, 2008, 4:52pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/21 "2008-09-15T16:52:01Z")
> [@mangeorge](#): > > High intelligence **had** to be pretty much universal before the developement of more complicated tools, such as points, knives with hafts, fishooks and the like. As these things came to be, each successive generation improved designs and taught these to the next. That’s what intelligence is, learning (but not teaching). But… What’s the point of intelligence if there’s nothing to be intelligent _about_? I mean, if we speculate that suddenly a proto human got a bit brighter than the rest, then natural selection would’ve favored it and others like it. But it seems to be more a question of \*emergence \*rather than something that suddenly was, which resulted in tool making. Wouldn’t the act of making tools actually increase intelligence? And wouldn’t the more intelligent individuals be better hunters and gatherers, thus invoking natural selection again? IANAP, just musing. ---
**Author:** ![MLS](https://avatars.discourse-cdn.com/v4/letter/m/919ad9/32.png) [@MLS](https://boards.straightdope.com/u/MLS)\ **Post date:** [September 15, 2008, 5:17pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/22 "2008-09-15T17:17:53Z")
Sorry, no cite, but I’ve read in a number of places that one of, if not the, first thing we became more intelligent about was relationships. The smarter one was able to more easily dominate his/her fellow apes and have more descendants. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [September 15, 2008, 5:50pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/23 "2008-09-15T17:50:55Z")
> [@Charlie\_Tan](#): > > But… What’s the point of intelligence if there’s nothing to be intelligent _about_? I mean, if we speculate that suddenly a proto human got a bit brighter than the rest, then natural selection would’ve favored it and others like it. But it seems to be more a question of \*emergence \*rather than something that suddenly was, which resulted in tool making. > Wouldn’t the act of making tools actually increase intelligence? And wouldn’t the more intelligent individuals be better hunters and gatherers, thus invoking natural selection again? > > IANAP, just musing. Depends. Brains are very expensive organs to maintain, so you need to improve nutrition considerably (and reliably) to keep that big chunk of grey matter going. If the tool use does that, then great. If not, then the bigger brain could be more of a detriment-- especially over many generations when food supplies are going to vary. ---
**Author:** ![muttrox](https://avatars.discourse-cdn.com/v4/letter/m/a8b319/32.png) [@muttrox](https://boards.straightdope.com/u/muttrox)\ **Post date:** [September 15, 2008, 5:59pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/24 "2008-09-15T17:59:15Z")
Before the Dawn, by Nicholas Wade has a lot of interesting things to say about recent evolution. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [September 15, 2008, 8:35pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/25 "2008-09-15T20:35:24Z")
> [@muttrox](#): > > Before the Dawn, by Nicholas Wade has a lot of interesting things to say about recent evolution. Yeah, that’s the stuff I was thinking of in my first post. Good book. Still, it’s important to keep in mind that the research is very new and I don’t think it’s widely accepted yet. ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [September 16, 2008, 3:28pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/26 "2008-09-16T15:28:10Z")
> [@MLS](#): > > Sorry, no cite, but I’ve read in a number of places that one of, if not the, first thing we became more intelligent about was relationships. The smarter one was able to more easily dominate his/her fellow apes and have more descendants. A guy by the name of (I think) Devlin wrote a book about this very topic called _The Math Gene_. There was actually very little about math in it. Enough to back up his assertion that math is a type of language and that it uses the language circuits in our brains. He then discusses when and why we evolved language. ‘When’ was settled on around 200,000 years ago. (200,000 years ago wasn’t the actual _beginning_ of language. He compares it to the huge growth in complexity and abstraction in human speech between the ages of about 2 and 3.) ‘Why’ was because humans became more social and needed to keep track of all the relationships in their families and societies. I’ll paraphrase: “When trying to find out why a trait evolved to begin with, it is often useful to study what it is used for now. Many uses for language have been proposed; art, education, warning others of danger, recording history, etc. But linguists can estimate what proportion of language falls into which category, and overwhelmingly language is used for one thing: Gossip.” ---
**Author:** ![Toxylon](https://avatars.discourse-cdn.com/v4/letter/t/f05b48/32.png) [@Toxylon](https://boards.straightdope.com/u/Toxylon)\ **Post date:** [September 16, 2008, 5:51pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/27 "2008-09-16T17:51:54Z")
The archaeological record of the past 40 000 years or so tells me human intelligence has been at it’s peak for at least that long. The lack of social safety nets and a high dependence on individual capabilities to even survive, let alone reproduce, has been used for an argument for greater average intelligence among prehistoric people compared to modern ones. ---
**Author:** ![Bad\_Astronaut](https://avatars.discourse-cdn.com/v4/letter/b/e19adc/32.png) [@Bad\_Astronaut](https://boards.straightdope.com/u/Bad_Astronaut)\ **Post date:** [September 16, 2008, 6:06pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/28 "2008-09-16T18:06:13Z")
It’s possible that even if there have been no genetic changes to the brain in hundreds of millenia, the modern “mind” is vastly different than those of the ancients. Philosopher Dan Dennett has made this claim - essentially that the mind is a “virtual machine” running on the brain hardware, to put it in programming terms. The “software” has allowed people to use their brains with greater power and efficiency. A very simple everyday example would be using mnemonic devices to increase the power of you memory. ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [September 16, 2008, 9:47pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/29 "2008-09-16T21:47:44Z")
> [@Bad\_Astronaut](#): > > It’s possible that even if there have been no genetic changes to the brain in hundreds of millenia, the modern “mind” is vastly different than those of the ancients. > > Philosopher Dan Dennett has made this claim - essentially that the mind is a “virtual machine” running on the brain hardware, to put it in programming terms. The “software” has allowed people to use their brains with greater power and efficiency. A very simple everyday example would be using mnemonic devices to increase the power of you memory. Well, but the argument has also been advanced that pre-literate people needed better memories, because they couldn’t rely upon written records. How much of the Iliad could any of us memorize? 😉 ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [September 16, 2008, 10:01pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/30 "2008-09-16T22:01:08Z")
> [@Tom\_Tildrum](#): > > Well, but the argument has also been advanced that pre-literate people needed better memories, because they couldn’t rely upon written records. > > How much of the Iliad could any of us memorize? 😉 Gov. Patterson of New York, who is legally blind, memorizes all his speeches. Why? Because he feels he needs to. (Memorizing a speech is harder than memorizing a song or poem, which were deliberately written to encourage memory cues. And you can make up new verses whenever you forget the old ones.) As a society, we have the muscles we need to do our work, and the brains we need to our work. That’s always been true. If people needed more strength or endurance or memory in earlier years, then they worked to develop those skills. If we as a society were to need to do so, we’d develop them just as well. I don’t see that anything has changed. ---
**Author:** ![ivan\_astikov](https://avatars.discourse-cdn.com/v4/letter/i/58f4c7/32.png) [@ivan\_astikov](https://boards.straightdope.com/u/ivan_astikov)\ **Post date:** [September 16, 2008, 10:10pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/31 "2008-09-16T22:10:45Z")
I think it’s all down to forest fires and famine. A starving tribe came across a cooked animal one day, and our desire to hunt was born. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [September 16, 2008, 10:34pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/32 "2008-09-16T22:34:06Z")
> [@ivan\_astikov](#): > > I think it’s all down to forest fires and famine. A starving tribe came across a cooked animal one day, and our desire to hunt was born. Tribe member: Boy am I hungry. Hey, look at that lion run down that zebra. Second tribe member: Disgusting, isn’t it? Eating raw food? All cold and bloody? Makes me sick. Tribe member: Me too. Have another plant stem. Second tribe member. Shoot, now it’s beginning to rain on top of all my hunger. Wow, that lightning bolt practically hit us. Tribe member: It hit that wildebeest. It’s all hot and smoky. Second tribe member: Let’s hack off a piece. Yum, yum, that’s sure tasty. Tribe member: Tasty and undoubtedly nutritious. We should do this more often. Second tribe member: How? You got any lightning in your back pocket? Tribe member: I don’t even have a back pocket! [Both laugh] Second tribe member: Well, it was a good day anyway. Tribe member: I’ll say. We invented commas! [The two walk home, chewing on plant stems.] ---
**Author:** ![brazil84](https://avatars.discourse-cdn.com/v4/letter/b/8491ac/32.png) [@brazil84](https://boards.straightdope.com/u/brazil84)\ **Post date:** [September 16, 2008, 10:35pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/33 "2008-09-16T22:35:11Z")
[another possibility](http://www.cinecultist.com/2001monkeys.jpg) ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [September 16, 2008, 11:32pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/34 "2008-09-16T23:32:56Z")
> [@brazil84](#): > > [another possibility](http://www.cinecultist.com/2001monkeys.jpg) My mind is still open on that idea. Far too much “impossible” has happened in the last fifty years. ---
**Author:** ![toadspittle](https://avatars.discourse-cdn.com/v4/letter/t/c0e974/32.png) [@toadspittle](https://boards.straightdope.com/u/toadspittle)\ **Post date:** [September 16, 2008, 11:38pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/35 "2008-09-16T23:38:08Z")
I agree that we can’t say that intelligence has evolved in any significant way since the Out of Africa explosion, at minimum. For example, there is no discernible difference in intelligence between Australian Aborigines, whose ancestors appear to have arrived on the continent some 40-50kya, and Europeans. Granted, there was likely trade and intermarriage between the Australians and the wave of Asian immigrants 2500ya, but it seems unlikely that the newcomers’ “intelligence genes” would have swept through the Australian population like wildfire during that time, and brought all of their intellects up. So, it seems like not much has happened in 50,000 years. ---
**Author:** ![rayh](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@rayh](https://boards.straightdope.com/u/rayh)\ **Post date:** [September 16, 2008, 11:58pm UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/36 "2008-09-16T23:58:23Z")
There is the theory of [bicameralism](http://en.wikipedia.org/wiki/Bicameral_mind). > [@](#): > > In psychology, bicameralism is a controversial hypothesis which argues that the human brain once assumed a state known as a bicameral mind in which cognitive functions are divided between one part of the brain which appears to be “speaking,” and a second part which listens and obeys. > > The term was coined by psychologist Julian Jaynes, who presented the idea in the 1976 book The Origin of Consciousness in the Breakdown of the Bicameral Mind, wherein he made the case that the bicameral mentality was the normal state of the human mind everywhere as recently as 3000 years ago. He used governmental bicameralism metaphorically to describe this state, where the stored up experience of the right hemisphere was transmitted to the left hemisphere via auditory hallucinations. This mental model was replaced by the conscious mode of thought, which Jaynes argues is based on metaphorical language. The idea that language is necessary for subjective consciousness or higher forms of thought has been gaining in acceptance in recent years, with proponents such as Daniel Dennett, William Calvin, Merlin Donald, John Limber, Howard Margolis, and Jose Luis Bermudez. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [September 17, 2008, 12:01am UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/37 "2008-09-17T00:01:13Z")
> [@ivan\_astikov](#): > > I think it’s all down to forest fires and famine. A starving tribe came across a cooked animal one day, and our desire to hunt was born. That is highly unlikely. Everything we know about our ancestors tells us that we started eating meat long before we started cooking it. And there is no indication that we ate only forest fire-cooked meat early on. We were probably (mostly) scavengers first, then hunters later. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [September 17, 2008, 12:02am UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/38 "2008-09-17T00:02:16Z")
> [@rayh](#): > > There is the theory of [bicameralism](http://en.wikipedia.org/wiki/Bicameral_mind). I read that book many moons ago. Very trippy, but I don’t think his idea took hold. ---
**Author:** ![mangeorge](https://avatars.discourse-cdn.com/v4/letter/m/d78d45/32.png) [@mangeorge](https://boards.straightdope.com/u/mangeorge)\ **Post date:** [September 17, 2008, 12:16am UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/39 "2008-09-17T00:16:32Z")
> [@John\_Mace](#): > > That is highly unlikely. Everything we know about our ancestors tells us that we started eating meat long before we started cooking it. And there is no indication that we ate only forest fire-cooked meat early on. We were probably (mostly) scavengers first, then hunters later. I read that early man scaveneged bones, using tools (rocks, I guess) to open them to get at the marrow. Other predators, for the most part, weren’t equipped to harvest that marrow. These peoples continued to eat the marrow after they became hunters and learned to cook. Can’t say I blame them. 🙂 ---
**Author:** ![rayh](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@rayh](https://boards.straightdope.com/u/rayh)\ **Post date:** [September 17, 2008, 12:19am UTC](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481/40 "2008-09-17T00:19:02Z")
> [@John\_Mace](#): > > I read that book many moons ago. Very trippy, but I don’t think his idea took hold. From here [Myths vs. Facts About Julian Jaynes’s Theory](http://www.julianjaynes.org/myths-vs-facts.php). > [@](#): > > Myth: No one in academia takes Jaynes’s theory seriously. > > Fact: Jaynes was in high demand as a lecturer, and was frequently invited to lecture at conferences and symposia and as a guest lecturer at colleges and universities, including Harvard, Columbia, Cornell, Emory, Johns Hopkins, Rutgers, Tufts, York, Dalhousie, Wellesley, Florida State, Northwestern, SUNY at Genesco, Plattsburgh, Oswego, and Brockport, the Universities of New Hampshire, Michigan, Pennsylvania, and Massachusetts at Amherst and Boston Harbor. He was Scholar-in-Residence at Skidmore, Lake Forest, and the University of Prince Edward Island. In 1983 he gave the keynote address at a conference on “Language: The Crucible of Consciousness.” In 1984 he was invited to give the plenary lecture at the Wittgenstein Symposium in Kirchburg, Austria. He gave six major lectures in 1985 and nine in 1986. He was awarded an honorary Ph.D. by Rhode Island College in 1979 and another from Elizabethtown College in 1985. A conference dedicated to studying Jaynes’s theory is organized every other year at the University of Prince Edward Island. Jaynes’s book was translated into Italian, Spanish, German, and French. I think people are starting to take some aspects of his theory seriously. Daniel Dennett was an early proponent of Jaynes who cites Jaynes in all of his books and is in agreement with Jaynes on the language-dependency hypothesis, at least. [Previous page](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481.md?page=1) [Next page](https://boards.straightdope.com/t/the-evolution-of-intelligence/463481.md?page=3)