Social Brain Hypothesis VS. Climatic Variability Hypothesis: Hominid Encephalization

[meLothedestroyerofworlds]

Please explain the reasoning behind your choice

Edited October 7, 2016 by HelloI'mmeLo

[DrmDoc]

Please explain the reasoning behind your choice

 

Perhaps you should add a little more about each hypothesis, for those of us who are unfamiliar, so that we might make a more informed vote--that is unless you are only interested in the votes and feedback of those who are informed.

[Strange]

Especially as the only reference to the "Climatic Variability Hypothesis" that I can find is this thread.

[meLothedestroyerofworlds]

Good idea, forgive me this is my first time posting on a forum like this. Do you know how to edit posts?

[Strange]

You only have a limited time to edit posts. That may have expired. You could add more information below...

[meLothedestroyerofworlds]

Social brain hypothesis:

The idea that the brain has incrementally increased overtime as a result from sociability, is an old one basically: Hominids evolved to live in large complex groups where extra cranial space is needed to remember other's intentions, names and ideologies. They used this enlarged brain, to trick others for food, impress the female hominids, and to establish themselves within the social hierarchy. Here is a a much more detailed version of this hypothesis here: http://kreativproces.dk/http:/kreativproces.dk/wp-content/uploads/2010/08/Dunbars-tal-og-reseach.pdf

Here is a study supporting the hypothesis: http://rspb.royalsocietypublishing.org/content/280/1765/20131151
Here is a study that does not support it: http://rstb.royalsocietypublishing.org/content/362/1480/561

Climatic variability hypothesis:

In the past Africa and areas where ancient hominids roamed were not stable environments, proponents of this hypothesis state that it was the need to constantly adapt to an ever changing environment that caused brain size to triple. Here is a more detailed version: http://humanorigins.si.edu/research/climate-and-human-evolution/climate-effects-human-evolution

Here is a study supporting the hypothesis: http://link.springer.com/article/10.1007%2Fs12110-007-9015-z
Here is a study that does not: http://rstb.royalsocietypublishing.org/content/367/1599/2130


EDIT: IMO I believe both had an obvious influence over our brain's evolution but I am interesting in learning which one you guys think had the bigger effect.

EDIT: Sorry the link I posted for supporting evidence of climatic variability was the wrong link I have corrected it though.

Edited October 7, 2016 by HelloI'mmeLo

[DrmDoc]

Now that I have a little more information, I believe that elements of both hypotheses likely contributed to increases in early human brain size; therefore, I didn't vote one hypothesis over the other. My perspective, however, isn't based on the particulars of those hypotheses but more so on what I recall of a comparative brain study among wild and domesticated animals. That study showed that domesticated species of certain animal groups have smaller brains than their wild cousins. As I recall, the author of that study suggested that the larger brain sizes of the wild animals was likely a result of the more varied experiences of those animals and the complex adaptive strategies they must assimilate to survive beyond that of domesticated spieces. Unfortunately, this dated link to a book chapter on brain size variances between dogs and wolves was the only article I was able to immediately find to support my recollection. Essentially, brain size is experience dependent but not necessarily indicative of intelligence. Perhaps the best evidence that size doesn't confer intelligence involves our Neanderthal cousins. Endocranial casts of Neanderthals suggest a brain size of greater volume than modern humans but nearly equal in encephalization. This distinction in brain size between modern humans and the Neanderthals suggests other survival factors may have compelled our superior intelligence. I believe those other survival factors compelled developments in significant regions of our brain that Neanderthals didn't require because of their more muscular physique and likely greater dependency on physical rather than intellectual strength.

Edited October 8, 2016 by DrmDoc

[meLothedestroyerofworlds]

"Essentially, brain size is experience dependent but not necessarily indicative of intelligence. Perhaps the best evidence that size doesn't confer intelligence involves our Neanderthal cousins"

Yes I heard about that study, Humans themselves are smaller brained today which some speculate is due to self domestication. I wasn't saying Brain size necessarily equals intelligence. The wiring of the brain itself is also important but with everything being equal a bigger brain is smarter especially within a species' variation. Neanderthals had a disproportionately large visual cortex and orbital sockets So their intelligence probably was more spatially orientated. Us humans were possibly more social. Also I agree that I think both played a role but I wanted to know which one you think had the bigger effect.


http://www.evoanth.net/2014/03/13/our-brain-is-shrinking-but-our-frontal-lobe-is-growing/

[EdEarl]

I didn't vote because I believe brain capability and size aren't strongly correlated, and your question (social vs climactic) may be incomplete. For example, I think brain size and birth canal size are related.

 

Neurons vary in size considerably within a person and among species, and neuron count varies widely among species.

 

Fairy wasps, which are about the size of a large amoeba have about 7,400 neurons (compared to a medicinal leech with 10,000). Most fairy wasp neurons have no nucleus.

 

 

Scientific American

Bird Brains Have as Many Neurons as Some Primates

An elephant has about 2.6x10¹¹ and a human has about 8.6x10¹⁰. I know it is a poor comparison, but it illustrates there is more involved with overall capability of a species than brain size.

 

Fossil evidence will not show whether neuron size and synapse count have changed over time. It seems possible neurons shrunk over eons, increasing the total number of neurons, which may have had greater significance than cranial volume.

 

There are too many things to consider, and I am not an expert in the field. I'll vote if you also poll chimpanzees, for I can do no better.

Edited October 8, 2016 by EdEarl

[DrmDoc]

"Essentially, brain size is experience dependent but not necessarily indicative of intelligence. Perhaps the best evidence that size doesn't confer intelligence involves our Neanderthal cousins"

 

Yes I heard about that study, Humans themselves are smaller brained today which some speculate is due to self domestication. I wasn't saying Brain size necessarily equals intelligence. The wiring of the brain itself is also important but with everything being equal a bigger brain is smarter especially within a species' variation. Neanderthals had a disproportionately large visual cortex and orbital sockets So their intelligence probably was more spatially orientated. Us humans were possibly more social. Also I agree that I think both played a role but I wanted to know which one you think had the bigger effect.

 

 

http://www.evoanth.net/2014/03/13/our-brain-is-shrinking-but-our-frontal-lobe-is-growing/

 

If your question regards which hypothesis had the greater impact on human intelligence, I think a critical distinction between modern humans and Neanderthals gives us a clue. As I understand, there is evidence that Neanderthals may have shared social bonds, had culture, and used tools much like modern humans. However, there is a critical distinction suggested by the nature of Neanderthal tools that further suggest something I consider crucial about their brain development, which directly relates to a distinction in the survival pressures (e.g., social, climate, etc.) promoting modern human brain development and intelligence over Neanderthals.

 

Neanderthals predate modern humans by about 200,000 years. Almost from the beginning of the their tool use and until about 40,000 years ago, Neanderthals tools remain not as sophisticated as modern humans would go on to develop during a shorter period of time. This is reasonable since Neanderthals were made of sturdier stuff than modern humans with thicker bones and a more muscular built. Modern humans had to devise strategies to compensate for their more fragile, less muscular frame to survive. Through out early modern human development, survival for them required a capacity to continually devise strategies to satisfy the emergent and evolving survival conditions and demands not met by their weaker physique. Tool and paleo evidence suggests that Neanderthals hunters/gathers didn't change or have to change their survival strategies significantly. The variety and refined nature of early modern human tools suggest that they more frequently than Neanderthals used their brains to devise survival tools and strategies. More than Neanderthals, I think modern humans had to plan and think more about their future and innovate tools to meet the demands of that future. In our brain, the prefrontal cortex is where we find activity associated evaluating consequential experience. The prefrontal is where we assess the future consequences of our actions and experiences. It gives us the ability to innovate and strategize based on the consideration of future possibilities. As your link provides "our frontal lobe is growing."

 

So, in answer to your query, the hypothesis that likely had the most impact on human intelligence is the one whose elements likely demanded continual development of survival tools and strategies--in my opinion.

[meLothedestroyerofworlds]

I didn't vote because I believe brain capability and size aren't strongly correlated, and your question (social vs climactic) may be incomplete. For example, I think brain size and birth canal size are related.

 

Neurons vary in size considerably within a person and among species, and neuron count varies widely among species.

 

Fairy wasps, which are about the size of a large amoeba have about 7,400 neurons (compared to a medicinal leech with 10,000). Most fairy wasp neurons have no nucleus.

 

An elephant has about 2.6x10¹¹ and a human has about 8.6x10¹⁰. I know it is a poor comparison, but it illustrates there is more involved with overall capability of a species than brain size.

 

Fossil evidence will not show whether neuron size and synapse count have changed over time. It seems possible neurons shrunk over eons, increasing the total number of neurons, which may have had greater significance than cranial volume.

 

There are too many things to consider, and I am not an expert in the field. I'll vote if you also poll chimpanzees, for I can do no better.

The correlation between brain size and intelligence is between .2 to .5 I believe. Birth canal size is more or less a mutation that compensates for brain size. Climate would probably correlate much higher if it kept getting cooler during our evolution. You may be unintentionally obfuscating the question, as I said before and as the other poster insinuated if you had a pair of clones where the only difference in their comparative anatomy was one being slightly bigger brained, the bigger brained clone would be more intelligent. I do not disagree with you though, there is fossil evidence of some hominids with brain sizes similar to Lucy, but the structure of their brain was much more modern and their tool set more complex.

 

https://pumpkinperson.com/2015/12/23/what-exactly-is-the-correlation-between-iq-and-brain-size-in-adults/

 

https://www.youtube.com/watch?v=nD9gtU_jdRA

 

^​ think that is the right youtube link please tell me if it doesn't say anything about the particular hominid.

 

If your question regards which hypothesis had the greater impact on human intelligence, I think a critical distinction between modern humans and Neanderthals gives us a clue. As I understand, there is evidence that Neanderthals may have shared social bonds, had culture, and used tools much like modern humans. However, there is a critical distinction suggested by the nature of Neanderthal tools that further suggest something I consider crucial about their brain development, which directly relates to a distinction in the survival pressures (e.g., social, climate, etc.) promoting modern human brain development and intelligence over Neanderthals.

 

Neanderthals predate modern humans by about 200,000 years. Almost from the beginning of the their tool use and until about 40,000 years ago, Neanderthals tools remain not as sophisticated as modern humans would go on to develop during a shorter period of time. This is reasonable since Neanderthals were made of sturdier stuff than modern humans with thicker bones and a more muscular built. Modern humans had to devise strategies to compensate for their more fragile, less muscular frame to survive. Through out early modern human development, survival for them required a capacity to continually devise strategies to satisfy the emergent and evolving survival conditions and demands not met by their weaker physique. Tool and paleo evidence suggests that Neanderthals hunters/gathers didn't change or have to change their survival strategies significantly. The variety and refined nature of early modern human tools suggest that they more frequently than Neanderthals used their brains to devise survival tools and strategies. More than Neanderthals, I think modern humans had to plan and think more about their future and innovate tools to meet the demands of that future. In our brain, the prefrontal cortex is where we find activity associated evaluating consequential experience. The prefrontal is where we assess the future consequences of our actions and experiences. It gives us the ability to innovate and strategize based on the consideration of future possibilities. As your link provides "our frontal lobe is growing."

 

So, in answer to your query, the hypothesis that likely had the most impact on human intelligence is the one whose elements likely demanded continual development of survival tools and strategies--in my opinion.

 

Actually my question was in regards to encephalization not human intelligence but I do equate the two so I guess it doesn't matter. Neanderthals were more advanced than us technologically until a little bit before we left Africa. I give their enhanced spatial abilities credit for that one. I n my opinion the demise of neanderthals was probably their inefficient bodies, competition with our bigger groups and interbreeding with a more genetically diverse species, we were very close in intelligence. So basically you subscribe to the Climatic variability hypothesis being the main force. Climate is correlated with resource allocation and resource allocation supplies a demand for continual development of tools and strategies. This is all assuming technological advancement is equivalent to intelligence but, I suspect this is not the case so I respectfully have to disagree with you. As I said earlier our brains are shrinking(except the frontal lobe) possibly due to self domestication and it has been shown that wolves are more intelligent than dogs, though they are less curious(which is positively correlated with intelligence.) My point is that even though now we have much more collective knowledge and technology our cro magnon and neanderthal ancestors were still more intelligent than us.

 

http://www.evoanth.net/2016/01/28/how-similar-were-neanderthals-and-humans/

 

http://www.evoanth.net/2015/12/10/are-humans-smarter-than-neanderthals/

 

http://phys.org/news/2015-09-wolves-problem-solving-task-domesticated-dogs.html

[DrmDoc]

Actually my question was in regards to encephalization not human intelligence but I do equate the two so I guess it doesn't matter.

 

It was my understanding that your question regarded influences on brain size and development, which includes measures of intelligence. Although I don't equate size with intelligence, I do equate experience with size and certain types of experience with developments and distinctions in the modern human brain that are associated intelligence.

 

Neanderthals were more advanced than us technologically until a little bit before we left Africa. I give their enhanced spatial abilities credit for that one.

 

I accessed the link you provided to a paper discussing Neanderthal technologies relative to humans in Africa. As I understand, the paper purports Neanderthals had a rate of tool innovation comparable to early modern humans but not necessarily more advanced. Although their Mousterian tool development preceded the Aurignacian tools of early modern humans, they weren't as refined or innovative. The distinction between the two is that modern humans in early Europe adapted and innovated their African technologies beyond those in use by their Neanderthal competitors. Early modern humans brought new and superior technologies to Europe when they arrived.

 

I don't equate the Neanderthal's larger visual cortex, eye sockets, and likely enhanced spatial acuity with greater intelligence in their tool development. These attributes may merely suggest they were likely more nocturnal in habits and better twilight or nighttime hunters that early humans.

 

In my opinion the demise of neanderthals was probably their inefficient bodies, competition with our bigger groups and interbreeding with a more genetically diverse species, we were very close in intelligence.

 

I think the Neanderthals were very well adapted for the fauna upon which they subsisted and the strategies they used to obtain subsistence. The fossil evidence, as I recall, suggests that they sustained considerable injuries, which some have associated with the likely physical nature of their hunting strategies. In my opinion, the dominant reasons for the Neanderthals demise are probably linked to their smaller social groups and an inability to adapt to a decline in the megafauna they hunted, which was likely precipitated by climate change and the arrival of early humans in Europe.

 

This is all assuming technological advancement is equivalent to intelligence but, I suspect this is not the case so I respectfully have to disagree with you. As I said earlier our brains are shrinking(except the frontal lobe) possibly due to self domestication and it has been shown that wolves are more intelligent than dogs, though they are less curious(which is positively correlated with intelligence.) My point is that even though now we have much more collective knowledge and technology our cro magnon and neanderthal ancestors were still more intelligent than us.

 

I think technology is indicative of intelligence particularly when that technology demonstrates the thoughtful nature of its development and its superiority to similar technologies (e.g., a sharpened wood spear versus a Clovis point). I don't believe a smaller brain volume relative to other hominids suggest that they were smarter than us anymore than I consider wolves as particularly smarter than dogs. Brain size is associated with experience and certainly other hominids and wolves had experiences that, in my opinion, modern humans and domesticated animals no longer have or endure. Our technologies, education, and domestication gave us conveniences that lessen demands on regions of our brain not as vital to our survival as they were or are to other species. We have devised strategies and technologies that more efficiently facilitate our survival and do not require the enhanced mind/body acuity of a hunter-gatherer. Although comparable areas of our brain may be shrinking consequently, our larger frontal cortex suggests how our early ancestors ability to communicate, foresee and prepare for their future survival needs might have uniquely favored their survival success.

Edited October 9, 2016 by DrmDoc

[meLothedestroyerofworlds]

 

It was my understanding that your question regarded influences on brain size and development, which includes measures of intelligence. Although I don't equate size with intelligence, I do equate experience with size and certain types of experience with developments and distinctions in the modern human brain that are associated intelligence.

 

 

I accessed the link you provided to a paper discussing Neanderthal technologies relative to humans in Africa. As I understand, the paper purports Neanderthals had a rate of tool innovation comparable to early modern humans but not necessarily more advanced. Although their Mousterian tool development preceded the Aurignacian tools of early modern humans, they weren't as refined or innovative. The distinction between the two is that modern humans in early Europe adapted and innovated their African technologies beyond those in use by their Neanderthal competitors. Early modern humans brought new and superior technologies to Europe when they arrived.

 

I don't equate the Neanderthal's larger visual cortex, eye sockets, and likely enhanced spatial acuity with greater intelligence in their tool development. These attributes may merely suggest they were likely more nocturnal in habits and better twilight or nighttime hunters that early humans.

 

 

I think the Neanderthals were very well adapted for the fauna upon which they subsisted and the strategies they used to obtain subsistence. The fossil evidence, as I recall, suggests that they sustained considerable injuries, which some have associated with the likely physical nature of their hunting strategies. In my opinion, the dominant reasons for the Neanderthals demise are probably linked to their smaller social groups and an inability to adapt to a decline in the megafauna they hunted, which was likely precipitated by climate change and the arrival of early humans in Europe.

 

 

I think technology is indicative of intelligence particularly when that technology demonstrates the thoughtful nature of its development and its superiority to similar technologies (e.g., a sharpened wood spear versus a Clovis point). I don't believe a smaller brain volume relative to other hominids suggest that they were smarter than us anymore than I consider wolves as particularly smarter than dogs. Brain size is associated with experience and certainly other hominids and wolves had experiences that, in my opinion, modern humans and domesticated animals no longer have or endure. Our technologies, education, and domestication gave us conveniences that lessen demands on regions of our brain not as vital to our survival as they were or are to other species. We have devised strategies and technologies that more efficiently facilitate our survival and do not require the enhanced mind/body acuity of a hunter-gatherer. Although comparable areas of our brain may be shrinking consequently, our larger frontal cortex suggests how our early ancestors ability to communicate, foresee and prepare for their future survival needs might have uniquely favored their survival success.

Well my logic was that a better eye meant a better eye for detail which would help in intricate designs and complex patterning of tool formation some would argue that the levallois techniques are easily the hardest to master of any tool set. Do you think because you are able to understand a concept like relativity that you could've come up with it on your own? Not trying to insult you but innovation has a lot more to do with how information is shared and passed down than with actual intelligence. Just so you know my preference is the social hypothesis. Here is a good link in regards to how innovation relates to intelligence: http://www.evoanth.net/2016/05/19/human-success-social/

 

What it shows is that the process of encephalization closely mirrors the pattern that is expected if innovation is almost completely reliant on cultural and social trends of our prehistoric ancestors.

 

https://en.wikipedia.org/wiki/Neanderthal_behavior#Language

 

Edited October 9, 2016 by HelloI'mmeLo

[DrmDoc]

Well my logic was that a better eye meant a better eye for detail which would help in intricate designs and complex patterning of tool formation some would argue that the levallois techniques are easily the hardest to master of any tool set. Do you think because you are able to understand a concept like relativity that you could've come up with it on your own? Not trying to insult you but innovation has a lot more to do with how information is shared and passed down than with actual intelligence. Just so you know my preference is the social hypothesis. Here is a good link in regards to how innovation relates to intelligence: http://www.evoanth.net/2016/05/19/human-success-social/

 

What it shows is that the process of encephalization closely mirrors the pattern that is expected if innovation is almost completely reliant on cultural and social trends of our prehistoric ancestors.

 

https://en.wikipedia.org/wiki/Neanderthal_behavior#Language

 

 

From your link and comments, it's my understanding that you perceive intelligence as a derivative of social interaction and that innovations evolve from those social experiences where information is passed from generation to generation or people to people. Therefore, as I understand, you favor the social hypothesis as likely the impetus for hominid encephalization. Indeed, innovations can and do arise from a sharing of information through social networks; however, innovations do not arise and become widespread without some need and someone with the intelligences to recognize and devise a tool or strategy to address that need. Innovations, in my opinion, are inventions of need that become more refined through social networking. Arising from need, the innovations of early hominids were likely first compelled by the evolving demands of their survival needs and conditions and were then further refined through their social interactions. Without the needs and demands of their survival, early hominids did not require the intelligence to create and innovate--which certainly favors a climate or environment related hypothesis. When assessing the comparative intelligence of early hominids, the comparative sophistication of their inventions and innovations is in my view is a reliable reflection of their intelligence distinction and the survival needs they addressed.

Edited October 9, 2016 by DrmDoc

[EdEarl]

The correlation between brain size and intelligence is between .2 to .5 I believe.

This correlation is for brain sizes of today. Since soft tissue does not survive in fossils, we cannot know if the soft tissue today is the same of different from soft tissue of fossils. Perhaps the larger brain cavity held less capable neurons or poorly organized neural networks, and the larger brains found in fossils held less less capable brains.

 

Neanderthals lived a rough life, fossils often show that bones were broken. This lifestyle suggests they may have also gotten concussions, which often damages brain tissue. A larger brain may have been an adaptation to accommodate frequent brain damage.

Edited October 9, 2016 by EdEarl

[meLothedestroyerofworlds]

 

From your link and comments, it's my understanding that you perceive intelligence as a derivative of social interaction and that innovations evolve from those social experiences where information is passed from generation to generation or people to people. Therefore, as I understand, you favor the social hypothesis as likely the impetus for hominid encephalization. Indeed, innovations can and do arise from a sharing of information through social networks; however, innovations do not arise and become widespread without some need and someone with the intelligences to recognize and devise a tool or strategy to address that need. Innovations, in my opinion, are inventions of need that become more refined through social networking. Arising from need, the innovations of early hominids were likely first compelled by the evolving demands of their survival needs and conditions and were then further refined through their social interactions. Without the needs and demands of their survival, early hominids did not require the intelligence to create and innovate--which certainly favors a climate or environment related hypothesis. When assessing the comparative intelligence of early hominids, the comparative sophistication of their inventions and innovations is in my view is a reliable reflection of their intelligence distinction and the survival needs they addressed.

I agree with you for the most part. It takes intelligence to innovate but it only requires sociality for it to spread and our archaeological record shows that it progresses in the pattern expected if it was mostly influenced by cultural learning. While I agree the invention of tool sets is more than likely caused by adapting for specific climates I have already stated I do not think tool set presence nor complexity is necessarily equated with intelligence, as my prior link had suggested. I believe sociality is the best explanation for our cultural, artistic and symbolic abilities. Problem solving is more or a less a side effect, and Isn't actually our mental strong suit.

This correlation is for brain sizes of today. Since soft tissue does not survive in fossils, we cannot know if the soft tissue today is the same of different from soft tissue in fossils. Perhaps the larger brain cavity held less capable neurons or poorly organized neural networks, and the larger brains found in fossils held less less capable brains.

 

Neanderthals lived a rough life, fossils often show that bones were broken. This lifestyle suggests they may have also gotten concussions, which often damages brain tissue. A larger brain may have been an adaptation to accommodate frequent brain damage.

Well humans have been anatomically and behaviorally modern since about 70,000- 140,000 years ago but that doesn't tell us much about the other 4 million years. Brain size isn't everything, but I do believe it is the best indicator we have in our fossil record for hominid intelligence. Are you suggested it was sort of like circuit redundancy or something? I heard a while back about a hypothesis that claimed our brains became bigger(initially) for circuit redundancy.

 

https://arxiv.org/ftp/arxiv/papers/1312/1312.5403.pdf

 

http://www.sciforums.com/threads/encephalization-of-early-hominids.145308/

Edited October 9, 2016 by HelloI'mmeLo

[DrmDoc]

I agree with you for the most part. It takes intelligence to innovate but it only requires sociality for it to spread and our archaeological record shows that it progresses in the pattern expected if it was mostly influenced by cultural learning. While I agree the invention of tool sets is more than likely caused by adapting for specific climates I have already stated I do not think tool set presence nor complexity is necessarily equated with intelligence, as my prior link had suggested. I believe sociality is the best explanation for our cultural, artistic and symbolic abilities. Problem solving is more or a less a side effect, and Isn't actually our mental strong suit.

 

As I now understand, you equate intelligence with evidence of culture, artistry, and symbolism rather than tool invention or their complexity. It is your belief, if I'm correct, that tool use and invention is an outcome of the abstract mental processes associated symbolism capabilities. Although I agree that qualities such as culture, artistry, and symbolism do indeed emerge from social influences, I do not agree that tool invention and, thereby, intelligence emerged from those influences. This seems to involve a question of whether the symbolism emerging from social pressures effected creativity and intelligence or whether the demands of survival is the impetus for that creativity leading to intelligence. I think we can answer that question clearly through the behavior of our primate cousins.

 

At the very least, we know that tool use is indicative of the emergence of intelligence and that chimpanzees fashion and use several tools for foraging and aggression. Although they are not human, they do have social groups and share information but do not appear to have culture or symbolism as we understand. In answering whether intelligence emerges from social or environmental factors, we merely have to ask ourselves which of those factors likely led to the initial emergence of tool use by contemporary species that approximate early hominids. Did the advent of tool fashioning and use among chimpanzees emerge from some internal, symbolic life inspired by social element or pressures...or did their tool use emerge from a need driven by survival related pressures and influences? Primate tool use appear to have emerged through the problem solving associated with their survival efforts. This suggest that intelligence, creativity, and symbolism among early humans likely emerge in a similar way and under similar influences. Intelligence emerge through problem solving and the problems our early ancestors likely encountered were those associated with their survival. Even our social needs are subordinate to and a subset of our overall survival imperatives.

Edited October 10, 2016 by DrmDoc

[arc]

 

From your link and comments, it's my understanding that you perceive intelligence as a derivative of social interaction and that innovations evolve from those social experiences where information is passed from generation to generation or people to people. Therefore, as I understand, you favor the social hypothesis as likely the impetus for hominid encephalization. Indeed, innovations can and do arise from a sharing of information through social networks; however, innovations do not arise and become widespread without some need and someone with the intelligences to recognize and devise a tool or strategy to address that need. Innovations, in my opinion, are inventions of need that become more refined through social networking. Arising from need, the innovations of early hominids were likely first compelled by the evolving demands of their survival needs and conditions and were then further refined through their social interactions. Without the needs and demands of their survival, early hominids did not require the intelligence to create and innovate--which certainly favors a climate or environment related hypothesis. When assessing the comparative intelligence of early hominids, the comparative sophistication of their inventions and innovations is in my view is a reliable reflection of their intelligence distinction and the survival needs they addressed.

 

Bold mine.

 

I believe the social hypothesis is the strongest of the two, in the early education of our own children we concentrate heavily on communication development which leads their demonstration of creativity by a appreciable degree of time.

 

I agree with you for the most part. It takes intelligence to innovate but it only requires sociality for it to spread and our archaeological record shows that it progresses in the pattern expected if it was mostly influenced by cultural learning. While I agree the invention of tool sets is more than likely caused by adapting for specific climates I have already stated I do not think tool set presence nor complexity is necessarily equated with intelligence, as my prior link had suggested. I believe sociality is the best explanation for our cultural, artistic and symbolic abilities. Problem solving is more or a less a side effect, and Isn't actually our mental strong suit.

 

I believe the mental development of our early ancestors was the result of a informational feedback cycle of learning. This all began within a singular cultural group that quickly advanced through language and story telling. I described it several times before in other similar discussions on this forum. The creativity seen by the development of tools is a byproduct of the development and expansion of our early ancestor's brain capacity for abstract thought, an ability developed through imagining stories told within the group.

I think the first human language, more than just those single proto words sounded when gesturing while hunting for example, but the first constructs of language began when our very early ancestors became aware of time, the first understanding of the concept of yesterday, today and tomorrow.

I have debated whether a past/present/future awareness would have been in place prior or would it have developed in tandem with language as simply a tool they constructed to communicate more clearly. It would seem to be a natural development in language, to refer to for example, what happened on a hunt, and then extend those "stories" out over time. And with these early humans, that knowledge of past/present/future makes way for experiences of regret and hope that could develop into primitive religion and then into philosophy.

This to me is possibly the driver of our brain evolution. Those who could communicate and imagine the images in stories and use that information could understand the world around them better and improve their chances to survive. This could be the engine that would progress brain development quickly.

I could see it being almost inevitable that once the concept of the past is understandable, a hunter injured for example, would contemplate that traumatic moment and feel the regret of the mistake. He would possibly reexamine the events leading up to the accident searching for a answer to his regret. These experiences would lead to either fear or hope for tomorrow depending on the severity of his wounds and his knowledge of the fate of others with similar injuries.

If the injured had been considered one of importance this could be quite traumatic for all those involved. This would likely create fertile grounds for superstition and the need to anticipate the possible dangers lying in wait for them tomorrow. This is an inevitable byproduct of increasing brain size. The increase of imagination that visualizes the stories with increasing complexity would also drive the superstition that would increasingly be included in those stories.

Those that could process this flow of information and apply it to survival would likely pass their more advantageous brain and possibly even their cultural "education system" of language and stories on to their offspring. This model of evolution is one that has an internal mechanism of an information feedback creating an accelerated development of brain size in human ancestors. I think language, the concept of past/present/future and the stories that advanced human understanding, developed together through mutual reinforcement, accelerating our ancestors development.

Edited October 10, 2016 by arc

[EdEarl]

I agree with you for the most part. It takes intelligence to innovate but it only requires sociality for it to spread and our archaeological record shows that it progresses in the pattern expected if it was mostly influenced by cultural learning. While I agree the invention of tool sets is more than likely caused by adapting for specific climates I have already stated I do not think tool set presence nor complexity is necessarily equated with intelligence, as my prior link had suggested. I believe sociality is the best explanation for our cultural, artistic and symbolic abilities. Problem solving is more or a less a side effect, and Isn't actually our mental strong suit.

Well humans have been anatomically and behaviorally modern since about 70,000- 140,000 years ago but that doesn't tell us much about the other 4 million years. Brain size isn't everything, but I do believe it is the best indicator we have in our fossil record for hominid intelligence. Are you suggested it was sort of like circuit redundancy or something? I heard a while back about a hypothesis that claimed our brains became bigger(initially) for circuit redundancy.

 

Homo sapiens sapiens are less prone to injury than homo neanderthalensis; thus, I suggested neanderthals may have developed circuit redundancy as an alternative to their large brain indicating superior intelligence. They may have been more intelligent, but artifacts found during digs don't suggest it.

 

I understand brain volume is one of the few indicators of intelligence we have that can be tracked into prehistory. Cave paintings and other art are also indicators of intelligence; they have been found as far back as 40K years. A Cro Magnon skull about 28K years old is supposed to be 15-20% larger than ours. That may be the skull of a giant, or it may represent an average Cro Magnon, IDK; the fossil record is Spartan, and my knowledge is pitifully incomplete. Scientists want to draw reasonable conclusions from the evidence, but I believe the evidence is so sketchy that new finds may overturn current reasonable conclusions. I'm skeptical.

[meLothedestroyerofworlds]

 

As I now understand, you equate intelligence with evidence of culture, artistry, and symbolism rather than tool invention or their complexity.

No I believe both are indicative of intelligence I just think it's presence is of necessity.

 

 

I think we can answer that question clearly through the behavior of our primate cousins. At the very least, we know that tool use is indicative of the emergence of intelligence and that chimpanzees fashion and use several tools for foraging and aggression. Although they are not human, they do have social groups and share information but do not appear to have culture or symbolism as we understand. In answering whether intelligence emerges from social or environmental factors, we merely have to ask ourselves which of those factors likely led to the initial emergence of tool use by contemporary species that approximate early hominids. Did the advent of tool fashioning and use among chimpanzees emerge from some internal, symbolic life inspired by social element or pressures...or did their tool use emerge from a need driven by survival related pressures and influences? Primate tool use appear to have emerged through the problem solving associated with their survival efforts.

I wouldn't underestimate our hairy cousins, friend. Chimps do have culture albeit a very simple one, they are also capable of imagination however they're not very innovative. I think the issue here is that you keep equating intelligence and innovation. Innovation arises out of necessity and sociability is simply what gives the necessary brain power to innovate. Arc is absolutely right, the ability to manipulate abstract concepts arises from social interactions through primitive forms of language. Problem solving is the side effect and we only really use it's full extent with it when it is necessary.

 

http://www.evoanth.net/2015/05/30/chimp-culture-includes-useless-things/

 

http://www.evoanth.net/2013/11/09/wild-chimps-seen-hunting-with-spears/

 

http://www.evoanth.net/2014/03/02/how-old-is-chimp-culture-finding-the-chimp-y-chromosomal-adam/

 

http://www.evoanth.net/2016/02/24/do-chimps-have-imagination/

 

https://en.wikipedia.org/wiki/Origin_of_language#Primate_communication

I believe the social hypothesis is the strongest of the two, in the early education of our own children we concentrate heavily on communication development which leads their demonstration of creativity by a appreciable degree of time.

I agree, that is a point I hadn't realized. A lot of immature animal offspring will "play" or mimic adult like activities to help them learn. Human children do this too however their play is almost always involved in creativity with their imagination. Both social ability and climate/ resource allocation had major impacts on hominid brain size but i still think sociability is the dominant factor.

 

https://en.wikipedia.org/wiki/Imitation#Imitation_in_animals

Homo sapiens sapiens are less prone to injury than homo neanderthalensis; thus, I suggested neanderthals may have developed circuit redundancy as an alternative to their large brain indicating superior intelligence. They may have been more intelligent, but artifacts found during digs don't suggest it.

 

I understand brain volume is one of the few indicators of intelligence we have that can be tracked into prehistory. Cave paintings and other art are also indicators of intelligence; they have been found as far back as 40K years. A Cro Magnon skull about 28K years old is supposed to be 15-20% larger than ours. That may be the skull of a giant, or it may represent an average Cro Magnon, IDK; the fossil record is Spartan, and my knowledge is pitifully incomplete. Scientists want to draw reasonable conclusions from the evidence, but I believe the evidence is so sketchy that new finds may overturn current reasonable conclusions. I'm skeptical.

I think cave art is a good indicator of intelligence and so is tool use, but the more complex tools by cro magnon could have been because of larger population density or numbers and not necessarily higher intelligence. I don't think neanderthals were more intelligent though I do believe neanderthals and cro magnon were still more intelligent than the average modern day humans. You have every right to be skeptical, interpreting fossil evidence can be incredibly subjective sometimes.

but the more complex tools by cro magnon could have been because of larger population density or numbers and not necessarily higher intelligence.

Nevermind, Population size has a negligible effect on creative output.

 

http://www.evoanth.net/2016/04/26/technology-evolve-not-population-size/

Edited October 10, 2016 by HelloI'mmeLo

[EdEarl]

Autism Exclusive To Humans, Neanderthals Lack DNA Sequence Responsible For Disorder

According to this article, homo sapiens sapiens developed these genes about 280,000 years ago, but other homo sapiens do not share it.

 

Temple Grandin said,

There tends to be a lot of autism around the tech centers... when you concentrate the geeks, you're concentrating the autism genetics.

 

I think that autistic brains tend to be specialized brains. Autistic people tend to be less social. It takes a ton of processor space in the brain to have all the social circuits.

Temple Grandin's website says,

All minds of the autism spectrum are detail-oriented, but how they specialize varies. By questioning many people both on and off the spectrum, I have learned that there are three different types of specialized thinking:

 

1. Visual thinking - Thinking in Pictures, like mine

2. Music and Math thinking

3. Verbal logic thinking

 

Since autism is so variable, there may be mixtures of the different types. The importance of understanding these three ways of thinking comes into play when trying to teach children with ASDs.

 

If Temple Grandin is right, then neanderthal smart may not have done much visual thinking, music and math thinking, or verbal logic thinking. This hypothesis may explain why we are artists and scientists and neanderthals were not.

[DrmDoc]

 

Bold mine.

 

I believe the social hypothesis is the strongest of the two, in the early education of our own children we concentrate heavily on communication development which leads their demonstration of creativity by a appreciable degree of time.

 

Encephalization, without consideration of intelligence, is primarily experience dependent and driven. In my view, some early hominids had larger overall brain volumes than modern humans because their lives were more dependent on their experiences than their technologies. Our larger frontal cortex by comparison, I believe, is an effect of our dependency on our invention and use of technology. As I previously commented, I agree that aspects such as culture, artistry, and symbolism are indeed indicative of intelligence; however, I also believe that tool invention and use is indicative of intelligence as well. The OP, in prior comments, believes these aspects emerged from social influences and pressures (SBH); whereas, I believe they emerged from survival related influences and pressures (CVH) such as the need for food, shelter, and defense. So, which hypothesis is valid? I think that questioned is best answered by what may have been the primary impetus for forming social groups.

 

I think we can agree that mating is instinct driven; however, we have evolved to have families and form social bonds because there was greater safety in numbers. The families, social bonds and connections our early ancestors formed were an effective strategy to support their survival. The culture, artistry, and symbolism we've inherited emerged from the survival needs of our early ancestors. But what about invention, innovation, and tool use? Did they emerge from socialization or some other influence? I think invention, innovation, and tool use would not have emerged among our ancestors without a need. So our question now becomes, did they emerge from a social need (needs of many) or some other more basic and compelling need?

 

Those most compelling need our ancestors likely faced was that of survival. Whether tool invention and use addressed the needs of the group or an individual, survival was the impetus for that invention and use. It's difficult for me to say whether tool invention and use emerged before or after the emergence of social groups but I think the idea of tool use likely emerge from a solitary effort. A single individual in need devised a tool to satisfy that need. Being a group member, that tool was refined and put to greater use among other group members. In my view, invention, innovation, and tool use emerged from solitary efforts influenced by survival need, which were then refined and expound by social groups. Therefore, if invention and tool use are indicative of intelligence, then that aspect of our intelligence likely emerged from survival strategizing (CVH) and was subsequently refined and expound by social collaboration (SBH).

Edited October 10, 2016 by DrmDoc

[meLothedestroyerofworlds]

If Temple Grandin is right, then neanderthal smart may not have done much visual thinking, music and math thinking, or verbal logic thinking. This hypothesis may explain why we are artists and scientists and neanderthals were not.

 

 

 

Yes but autists are a small minority of the human population.

 

 

Encephalization, without consideration of intelligence, is primarily experience dependent and driven. In my view, some early hominids had larger overall brain volumes than modern humans because their lives were more dependent on their experiences than their technologies.

What do you mean? Elaborate more.

 

 

 

The families, social bonds and connections our early ancestors formed were an effective strategy to support their survival. The culture, artistry, and symbolism we've inherited emerged from the survival needs of our early ancestors. But what about invention, innovation, and tool use? Did they emerge from socialization or some other influence? I think invention, innovation, and tool use would not have emerged among our ancestors without a need. So our question now becomes, did they emerge from a social need (needs of many) or some other more basic and compelling need?

But in that sense almost all evolution is driven by survival needs. It just seems oversimplified. I agree, though innovation arises from necessity and carried by social bonds.

 

Those most compelling need our ancestors likely faced was that of survival. Whether tool invention and use addressed the needs of the group or an individual, survival was the impetus for that invention and use. It's difficult for me to say whether tool invention and use emerged before or after the emergence of social groups but I think the idea of tool use likely emerge from a solitary effort. A single individual in need devised a tool to satisfy that need. Being a group member, that tool was refined and put to greater use among other group members. In my view, invention, innovation, and tool use emerged from solitary efforts influenced by survival need, which were then refined and expound by social groups. Therefore, if invention and tool use are indicative of intelligence, then that aspect of our intelligence likely emerged from survival strategizing (CVH) and was subsequently refined and expound by social collaboration (SBH).

 

I basically agree with everything being said here.

Edited October 10, 2016 by HelloI'mmeLo

[EdEarl]

@Lo

 

Yes but autists are a small minority of the human population.

So are scientists, but they tend to have a disproportionately large affect on culture.

[DrmDoc]

What do you mean? Elaborate more.

 

I was thinking about the idea that intelligence can be measured by brain volume or size. Given what we know about the larger volume of Neanderthal brains relative to early modern humans and if that larger brain idea is valid, our assumption should be that Neanderthals were likely smarter than their early modern competitors. However, the comparative evidence among Neanderthal artifacts and remnants of their settlements suggest that they likely were not as intelligent. Early humans had greater evidence of artistry and devised tools in varieties and sophistication exceeding those of the Neanderthals. Perhaps the best evidence for the superior intelligence of our ancestry is measured by how advanced our society has become relative to Neanderthals during a equal period of emergence and existence. The age of Neanderthals was twice as long as our ancestry, yet we have advanced much further in society and technology than they did. This forces us to consider what other factors might have contributed to Neanderthals having such a larger brain but not have greater intelligence.

 

We know from earlier links in our discussion that experience can and does influence brain size. Domesticated animals have smaller brains because their experiences are not as rich and varied as their wild cousins. We also know that Neanderthals brains were larger by volume but not as frontally large as ours relatively. These differences in brain growth suggest a distinction between the experiences of Neanderthals and modern humans producing that growth. We can assess the distinct and different experiences between the two species from the behaviors suggested by their differing areas of brain development--assuming, of course, that their brains were functionally configured similarly.

 

If Neanderthals brains were functionally configures as ours, there areas of superior parietal, temporal, and occipital growth suggest more sensory oriented behaviors and thought processes. Neanderthals had brains that favor their physical, sensory oriented lifestyle, which was a life of varied physical and sensory experiences. The superior frontal size of our ancestors brains suggests their greater dependency on thought processes such as problem solving, planning, and reasoning. This frontal cortical function favors a technology oriented and driven lifestyle. Evidence of this distinction between the two is suggested by their weaponry where Neanderthal favored close quarter weapons while early modern humans produced weapons that were lethal as a distance. Clearly, this suggests that early humans were more dependent on technology for their survival while the Neanderthals were more dependent on their physicality and sensory experiences.

 

But in that sense almost all evolution is driven by survival needs. It just seems oversimplified. I agree, though innovation arises from necessity and carried by social bonds.

 

Indeed it may be oversimplification, but that is the nature of evolution where a species proliferation is survival dependent. The species that evolve better survival attributes and strategies will likely thrives beyond its competitors as we have beyond the Neanderthal.

Edited October 10, 2016 by DrmDoc