# The evolution of human intelligence - why?



## oscarea (Dec 10, 2013)

I've been thinking a lot about human intelligence and evolution recently. The earth has been inhabited by living organisms for billions of years and we are seemingly the first to have attained such a level of relative intelligence. 

Why? For what purpose, if any?

From an evolutionary stand point, what possible reasons would we need intelligence as a species? We have inhabited the earth for only a very short portion of it's history and yet we have done more damage to earth than other species before us. What does this suggest about the course of our evolution? 

Is our own intelligence is the cause of many of the issues we face today as species? I realise these are very broad, speculative questions that can be approached in many different ways, I'm curious to see what other people know of this particular topic or if they have any personal theories.


----------



## PowerShell (Feb 3, 2013)

oscarea said:


> From an evolutionary stand point, what possible reasons would we need intelligence as a species? We have inhabited the earth for only a very short portion of it's history and yet we have done more damage to earth than other species before us. What does this suggest about the course of our evolution?


Because that's our only evolutionary advantage. Go against pretty much any wild animal and it will naturally be faster or stronger than most humans along with sharper teeth. The only thing we have going for us is our ability to reason and create technology. Often times when we create technology to solve one problem, we end up creating some sort of other problem (often of greater magnitude). For example, we no longer have to really worry about a mass famine taking out the majority of the population in the Western world, but the technology we create to make this agricultural abundance possible, has created problems like erosion and run-off.


----------



## Derange At 170 (Nov 26, 2013)

oscarea said:


> I've been thinking a lot about human intelligence and evolution recently. The earth has been inhabited by living organisms for billions of years and we are seemingly the first to have attained such a level of relative intelligence.
> 
> Why? For what purpose, if any?


Survive.



oscarea said:


> From an evolutionary stand point, what possible reasons would we need intelligence as a species?


To make up for physical shortcomings that would have otherwise disabled us from inhabiting as many different habitats as we do.

And that's solely us. One trait doesn't always work for the same reason in every species or as much. Hyperintelligence has its drawbacks and its positives. And the positives are working in our favor. Why? Too many factors to name to be accurate. I could name a few but it would feel incomplete. Every organism has traits that were selected as being the most helpful in getting that particular organism's genes into the next generation. Through a clusterfuck of pressures, mutations and occurrences, it turned out that intelligence was beneficial to us, despites its drawbacks (slow development to an adult with limited mobility in our formative years, premature birth, oversized head making the birth process more dangerous for both mother and child, and so on).



oscarea said:


> We have inhabited the earth for only a very short portion of it's history and yet we have done more damage to earth than other species before us.


No, we changed it. That's what we realistically did. We didn't 'damage' anything. Some species, other than our own, are benefiting from our presence, others are facing difficulties because of it. That's sort of how it works when one clade of organisms is dominant. We're just introducing new selective pressures. So far there's more humans around today than there were just 100 years ago. Our environment is definitely working for us.

When the first predators evolved eyes, they probably wreaked havoc on their environment. Organisms either had to keep up with them or died out. Why should it be any different with us?

You know, one man's treasure is another man's trash? That applies here too. Our environment may be a trash to some species, but a treasure to others (us, cats, dogs, seagulls, cockroaches, etc).



> What does this suggest about the course of our evolution?


Nothing. Evolution isn't the voice of our planet's sentience. It's the name we gave to an observable occurrence in nature. "Evolution" as a concept isn't inherent. It's our interpretation of how organisms sustain themselves. It makes no absolute qualitative statements.



> Is our own intelligence is the cause of many of the issues we face today as species? I realise these are very broad, speculative questions that can be approached in many different ways, I'm curious to see what other people know of this particular topic or if they have any personal theories.


What problems are we facing as a species? I think we're quite successful. We continue to increase in numbers.


----------



## La Li Lu Le Lo (Aug 15, 2011)

This is another philosophical topic.


----------



## JoetheBull (Apr 29, 2010)

La Li Lu Le Lo said:


> This is another philosophical topic.


The way it is phrased does sound like it. But OP probably looking more for a science based answer rather than a philosophical based one like Derange At 170 gave. Now if he is trying to spark a creationist vs evolution debate then its a philosophical topic.

What I am trying to say is, the intent of the OP depends on whether or not this in the right topic area. Since I don't know his mindset. Can't be sure.


----------



## Derange At 170 (Nov 26, 2013)

JoetheBull said:


> The way it is phrased does sound like it. But OP probably looking more for a science based answer rather than a philosophical based one like Derange At 170 gave. Now if he is trying to spark a creationist vs evolution debate then its a philosophical topic.


I was more attempting to highlight how philosophy should stay out of this since the way the OP posed the question, our hyperintelligence is no different than let's say, the feather of a bird or the eyes of a fly. And I felt like the OP already injected philosophy into it by somehow arguing as if 'evolution' is going againsts its own supposed purpose with our hyperintelligence ("damaging our planet" etc).


----------



## oscarea (Dec 10, 2013)

I was looking at it intially from a more scientific viewpoint - I'm definitely not interested in a creationist / evolution debate. Although judging from the answers given, which were helpful, the depth of answers I'm seeking will probably be found through a philosophical discussion.


----------



## Hypathia (Nov 20, 2013)

I cannot recommend you enough:


----------



## LeafStew (Oct 17, 2009)

This neuroscientist made some research to find out what makes the human brain special. It's pretty interesting: 
Suzana Herculano-Houzel: What is so special about the human brain? | Video on TED.com


----------



## Orange Fusion (Nov 16, 2013)

oscarea said:


> I've been thinking a lot about human intelligence and evolution recently. The earth has been inhabited by living organisms for billions of years and we are seemingly the first to have attained such a level of relative intelligence.
> 
> Why? For what purpose, if any?
> 
> ...


The reason for us being so "intelligent" may be nothing more complicated than the fact we have developed large, efficient brains.


----------



## aef8234 (Feb 18, 2012)

The closest thing our "species" as a whole had to going to the "buff" side of evolution was the neanderthals, and we bonked them to death, had sex with our cheerleader waifu and then reproduced errwhere, ergo evolution.

The suggestion of our evolution is that it's the peak of it, I mean how much better can be within mother nature, other than to destroy it?

*WITH RADIOACTIVE VAPOR!*


----------



## iloveusarita (Nov 9, 2013)

oscarea said:


> I've been thinking a lot about human intelligence and evolution recently. The earth has been inhabited by living organisms for billions of years and we are seemingly the first to have attained such a level of relative intelligence.
> 
> Why? For what purpose, if any?
> 
> ...


Well evolution has no end goal or known purpose, it is simply just is.

That said, evolution's effects are largely accident, and it so happened that our line of mammals developed the intelligence to prosper. It's not God or whoever who planned this, as far as we know.

As for why we needed intelligence, I guess as we evolved in Africa it was a combination of better diet, tool use, more complex social interactions, and it snowballed upwards.


----------



## azdahak (Mar 2, 2013)

oscarea said:


> I've been thinking a lot about human intelligence and evolution recently. The earth has been inhabited by living organisms for billions of years and we are seemingly the first to have attained such a level of relative intelligence.
> 
> Why? For what purpose, if any?
> 
> ...



I think the first thing to realize is that no physical process has a purpose. The Colorado had no intention to carve out the Grand Canyon. It simply did. 

As as to why it took billions of years for intelligence to evolve, that is a matter of statistics. Unfortunately to date, we have only one datum. Perhaps once we gain a greater understanding of how our intelligence works, it may be possible to posit some sort of complexity minimum for a substrate in which intelligence can appear. 

Intelligence has been a highly successful evolutionary tactic....it allowed humans to dominate every ecological niche, and become the only species capable of leaving the biome of earth on their own volition. But it comes at a great cost....all the "near misses" ....our ape cousins...are evolutionary failures. 

The "course" of our evolution is an illusion we see looking back into our history and imagining a guiding hand. If we could "rewind" the history of earth, it's very likely humans wouldn't exist -- our species went through a population bottle neck and almost went extinct. A quintillion different rolls of the die, and things would be different.

However, the future course is our own. We are the only species capable of purposefully and methodically altering our own genome.


----------



## OldManRivers (Mar 22, 2012)

aef8234 said:


> The closest thing our "species" as a whole had to going to the "buff" side of evolution was the neanderthals, and we bonked them to death, had sex with our cheerleader waifu and then reproduced errwhere, ergo evolution.
> 
> The suggestion of our evolution is that it's the peak of it, I mean how much better can be within mother nature, other than to destroy it?
> 
> *WITH RADIOACTIVE VAPOR!*


The Neanderthals were superbly suited to life in a glacial period, and their IQ may not be known, but they were as aware as the Cro-Magnon people who absorbed them via interbreeding. Still, they lived in one area around Spain for millenia coexisting with Cro- Magnon. It was not intelligence that caused heir disappearance, it was their lack of adaptability to changing climatic conditions. And there was an article in Scientific American many years ago that had an image of how a Neanderthal would look on a city street today, based on skeletal remains. He would not have got a second look. We are their descendants. They were around lots longer that modern man has been.


----------



## aef8234 (Feb 18, 2012)

OldManRivers said:


> The Neanderthals were superbly suited to life in a glacial period, and their IQ may not be known, but they were as aware as the Cro-Magnon people who absorbed them via interbreeding. Still, they lived in one area around Spain for millenia coexisting with Cro- Magnon. It was not intelligence that caused heir disappearance, it was their lack of adaptability to changing climatic conditions. And there was an article in Scientific American many years ago that had an image of how a Neanderthal would look on a city street today, based on skeletal remains. He would not have got a second look. We are their descendants. They were around lots longer that modern man has been.


Ah.

The more you know.
Still, didn't the neanderthals get wiped out due to the encroachment of other species?


----------



## LadyO.W.BernieBro (Sep 4, 2010)

OldManRivers said:


> The Neanderthals were superbly suited to life in a glacial period, and their IQ may not be known, but they were as aware as the Cro-Magnon people who absorbed them via interbreeding. Still, they lived in one area around Spain for millenia coexisting with Cro- Magnon. It was not intelligence that caused heir disappearance, it was their lack of adaptability to changing climatic conditions. And there was an article in Scientific American many years ago that had an image of how a Neanderthal would look on a city street today, based on skeletal remains. Heto rush things would not have got a second look. We are their descendants. They were around lots longer that modern man has been.


The more recent documentaries are interesting :happy:

Lots of reason they were made to look like they died out as a result of low intelligence-the scientific community wanted to buy this explanation to rush things along in the early 1900's.

Also a misconception about their speech-they most likely didn't grunt but had an oddly shaped larynx. 

They would have made, almost chirping sounds according to one article, so they didn't communicate extraordinarily well verbally but some theorize they had superior non-verbal communication skills .


----------



## azdahak (Mar 2, 2013)

OldManRivers said:


> The Neanderthals were superbly suited to life in a glacial period, and their IQ may not be known, but they were as aware as the Cro-Magnon people who absorbed them via interbreeding. Still, they lived in one area around Spain for millenia coexisting with Cro- Magnon. It was not intelligence that caused heir disappearance, it was their lack of adaptability to changing climatic conditions. And there was an article in Scientific American many years ago that had an image of how a Neanderthal would look on a city street today, based on skeletal remains. He would not have got a second look. We are their descendants. They were around lots longer that modern man has been.



I have a bit of scholarly knowledge of this so I'll share the academic controversies going on in the journals currently:

The extent of the Neanderthal range covered most of continental Europe and parts of Eurasia which at the time was a steppe-tundra to temperate woodland environment, something like this:









How the Neanderthals died out is still an ongoing controversy, but indeed there is clear evidence of cross-species interbreeding:
A typical modern European or Asian (compared to sub-Saharan African) shares about 1-4% of Neanderthal genes. Additionally, SE Asians have a percentage of Denisovan DNA in their genome. 

The most recent complete Neanderthal sequence (Dec 2013) estimated that our genetics are 99.7% identical, and that genes that involve keratin production (skin, hair, nails), hair and skin pigmentation, and immune responses seem to be what got preserved. This is consistent with an African population acquiring the defense mechanisms they would need to survive in a colder climate with novel diseases. It is estimated that about 20% of the Neanderthal genome still exists across the modern human gene pool.

Interestingly, it seems that the X chromosome does not contain any Neanderthal DNA, which could imply that male human-Neanderthal hybrids were sterile. They never passed on their hybrid-X chromosome, so it eventually got filtered out of the population.
It seems that modern human-Neanderthal hybridization was on the razor edge of subspecies compatibility.

So it's clear that while there was interbreeding, it is still unknown what was the dominant force that lead to Neanderthal extinction...out-competed by modern humans, interspecies war, genetic absorption, climate change, lack of adaptability, etc. 

A Neanderthal on the modern streets today more than likely _would_ get a second look (sloped forehead, brow ridges, etc) but they're certainly within range of what we would consider human.









For instance, people with acromegaly can have these types of features, like Nikolai Valuev:

View attachment 92106



One thing we can say, is that we are *not* the descendants of Neanderthals. Our species originated in Africa. Modern sub-Saharan Africans do not have any Neanderthal DNA. Europeans and Asians interbred with a cousin sub-species and absorbed some of their genes. 

One thing to keep in mind is that the Neanderthals were _already_ on their way out before modern man even got into Europe. You can estimate their population size from genetic similarity. It's estimated to be below 10,000 individuals. So when you talk about coexistence, you have to remember their population density. Europe is about 10M sq. km. So that means you have on average, roughly 1 individual in an area the size of Portugal.

When modern humans showed up in Europe, they very quickly spread-out and dominated all ecological niches. While I personally don't think we hunted them to extinction (doesn't seem consistent with inter-breeding), I don't think we did them any favors showing up with our new ideas about tools, hunting techniques, cave art (abstract thinking -- some cave art are clearly star maps), a fully modern language ... and all the other things that seem to be primarily associated only with modern humans. 

The Neanderthal Mousterian tool culture remained virtually unchanged for 300,000 years. Modern-human culture has gone from rubbing sticks to make fire to harnessing the atom in 1/10 the time. 

So clearly, of all the failed **** species, ours had a unique type of intellect.

And that's what this debate is all about: Behavioral modernity - Wikipedia, the free encyclopedia


----------



## azdahak (Mar 2, 2013)

Lady O.W. Bro said:


> The more recent documentaries are interesting :happy:
> 
> Lots of reason they were made to look like they died out as a result of low intelligence-the scientific community wanted to buy this explanation to rush things along in the early 1900's.
> 
> ...



They weren't really "made to look" like anything. This is just the scientific process at work in a very active, cutting edge field. People make speculations, and others either support or disprove them. And so it goes.

The problem with the paleontological approach is that when you dig up a site...it's gone. You can't re-do the "experiment" as it were, and you're destroying evidence that perhaps future technology would be better able to analyze.


Of course the problem with speculating on Neanderthal behavior is that there are no Neanderthals to observe. We can only infer from the very scant evidence left behind. 

The larynx stuff is based on reconstructions and the recovery of exactly one hyoid bone in a Neanderthal skeleton. There's a lot of problems extrapolation one bone (especially since you're can't even be positive it's not from a hybrid, etc) into a theory about speech capabilities. And an even bigger one to suggest that since they couldn't talk, they used sign language. 

There is one theory which I find somewhat pleasing...namely that language evolved from a musical precursor and that the Neanderthals may have used such a thing. Evolutionary musicology - Wikipedia, the free encyclopedia


----------



## OldManRivers (Mar 22, 2012)

@azdahak 

A clarification -I meant that we have ancestors who were Neanderthal, so in that we are their descendants - the only ones they have. I did not of course descend solely from my 3rd great-grandfather, but my Y- DNA came from him with a few mutations. A miniscule fraction of his other genes came to me admixed with that of all the other third Great-grandparents. 

I had some interest in mules - horse mare/ ass stallion hybrids. I only casually read the article, but the female mule egg contains only horse chromosomes - a specific separation in the formation of gametes. Occasionally female mules are fertile but male mules are always sterile. Maybe something similar in early man?

I agree the adaptability of Cro-Magnon far surpassed the Neanderthal. The illustration is of the Late Neanderthal, isn't it? The early type were more modern in looks - not so pronounced brow ridges. The stoop-shouldered vacant face of early illustrations was to separate Man - the Pinnacle of Creation - from a lesser beast of the field. Religion and not science ruled.
I enjoyed your post!


----------



## azdahak (Mar 2, 2013)

OldManRivers said:


> @_azdahak_
> 
> A clarification -I meant that we have ancestors who were Neanderthal, so in that we are their descendants - the only ones they have. I did not of course descend solely from my 3rd great-grandfather, but my Y- DNA came from him with a few mutations. A miniscule fraction of his other genes came to me admixed with that of all the other third Great-grandparents.
> 
> ...


I take your point, but I still wouldn't use the word descendent. Africans have no Neanderthal ancestors. So humans as a species are not descended from Neanderthals. Rather, some populations of humans have hybridization events in the past. This is more in line with the way the word "descent" is used in evolutionary genetics.

Early illustrations were just that: a first stab guess at what Neanderthals looked like before more research was done. It's not so much that religion was in control, as much as it had already set the default bias. If anything, some of the early attacks of anti-evolutionists were to emphasize these beastly descriptions, because it emotionally supported their agenda -- that grandpa was a fearsome gorilla.

But you can see science at work by comparing what people first thought Megalosaurus looked like 150 years ago:


----------



## OldManRivers (Mar 22, 2012)

azdahak said:


> I take your point, but I still wouldn't use the word descendent. Africans have no Neanderthal ancestors. So humans as a species are not descended from Neanderthals. Rather, some populations of humans have hybridization events in the past. This is more in line with the way the word "descent" is used in evolutionary genetics.


Correct - a Eurocentric response? It was not deliberate. Just an all inclusive We.
And I speak from a social services and not from a scientific background.
The point on religion - I have read that dinosaur fossils were once identified as the remains of "the giants" mentioned in Genesis.


----------



## azdahak (Mar 2, 2013)

OldManRivers said:


> Correct - a Eurocentric response? It was not deliberate. Just an all inclusive We.
> And I speak from a social services and not from a scientific background.
> The point on religion - I have read that dinosaur fossils were once identified as the remains of "the giants" mentioned in Genesis.


Oh, I know what you meant. I just felt the need to clarify the wording because an old defunct theory was that modern humans descended from Neanderthals. 

Dinosaur bones were interpreted by Biblical "scholars" out to prove Gensis. No scientist uses the Bible as a basis for argument.

My general point is that religion holds no sway over the doings of science on the whole....any interference or bias eventually gets swept out by the method.....but.of course it still holds tremendous sway in the court of public opinion, which is why seemingly perfectly rational people believe in angels, ghosts, astrology, and Scripture, despite what science says.


----------



## aphinion (Apr 30, 2013)

Intelligence is one of the best traits to have when in pursuit of power, possessions, and respect.


----------



## SuperDevastation (Jun 7, 2010)

It's obvious, God made us to be the superior species.


----------



## koalaroo (Nov 25, 2011)

"Why" is really an unnecessary question.


----------



## PowerShell (Feb 3, 2013)

SuperDevastation said:


> It's obvious, God made us to be the superior species.


Hell yeah!


----------



## marsal (Feb 1, 2014)

Seems only natural for a evolutionary innovation in a species to improve and refine itself over time. There must be an advantage to our species for our intelligence to improve upon itself. Hopefully our moral development and common sense will catch up before this "intelligence" destroys everything. There goes my cynicism again


----------

