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View Full Version : Cro Magnon skull supports theory that human brains have begun to shrink



Sol Invictus
03-14-2010, 02:10 PM
Times Online | March 13 2010
http://www.timesonline.co.uk/tol/news/science/article7060327.ece

Humans like to portray themselves as a sophisticated life form driven by brain rather than brawn. So they may be surprised by a project to reconstitute a 28,000-year-old skull from remains found in France.

This has provided evidence to support a theory that our brains have begun to shrink.

The French team that claims to have produced one of the best replicas yet of an early modern human skull say that it is 15 to 20 per cent bigger than ours. No one suggests that we are 15 to 20 per cent more stupid than Cro Magnon 1, the best preserved of five skeletons discovered in 1868 in the Cro Magnon cave in the Dordogne, because there is only a minor link between brain size and intelligence.

It may be that, rather like computers, our brains are becoming more efficient even as they grow smaller. But the project could shed light on a human evolutionary question that has divided and bemused the specialists: if indeed our heads have started to shrivel, why is this happening?

Cro Magnon 1 has been kept in the French National Museum of Natural History in Paris. He is believed to have been a well-built, elderly man about 6ft tall. Already known to scientists worldwide, Cro Magnon 1 will become even more famous next week when a mold of his skull will be shown at the American National Museum of Natural History in Washington.

The endocast was made by scanning the interior of the skull at the Quinze-Vingts Hospital in Paris to obtain a picture of the impression left by the brain on the neurocranium.

Antoine Balzeau, of the French Museum of Natural History, transformed this into a 3D image that was in turn made into a mold by a specialist software prototyping firm.

“It’s one of the most beautiful endocasts ever,” Mr Balzeau told The Times. He said that an initial assessment of Cro Magnon 1’s skull confirmed the belief that brains had grown "slightly smaller over tens of thousands of years”, reversing an earlier trend towards bigger brains.

However, he said that the cerebellum — a brain structure linked to language and concentration — appears to take up a larger proportion of the head now than in the time of Cro Magnon 1. This suggests that some parts of the brain are more “compressible” than others, he said.

Several theories have been advanced to explain the mystery of the shrinking brain. One is that big heads were necessary to survive Upper Paleolithic life, which involved cold, outdoor activities.

A second theory is that skulls developed to cope with a chewy diet of rabbits, reindeer, foxes and horses. As our food has become easier to eat, so our heads have stopped growing, according to supporters of this theory.

Other experts say that with high infant mortality, only the toughest survived — and the toughest tended to have big heads.

Lenny
03-14-2010, 02:43 PM
This is nothing new -- It's been known for decades that CroMagnon man was the intellectual superior of his modern descendants, if we can judge by brain size (which does correlate with IQ among modern human groups).

Many say that the main culprit for our intellectual decline is actually Agriculture, for allowing far more people to survive than otherwise would have, depressing human quality. In the past, the lowest elements died off; With agriculture, those same lower elements survived because food was plentiful and life was relatively easy. In fact, the lower-elements of a society are usually the most prolific [having more children].

Agrippa
03-18-2010, 10:15 AM
Its all nutrition related. Today there are enough people around with bigger brains than those of Cro Magnon, yet they are a small minority and yes, brainsize is not everything.

But if considering that progressive-mature forms have both large brains and a highly effective body, the reason for their decline in numbers can never be effectiveness, but only additional factors, like those I usually describe with Alpinisation and Baltisation - partly probably sexual selection.

Reduction and Infantilisation is a response to a lack of energy and bad living conditions. Cro Magnon was also taller than farmers in medieval times were and the herders/mixed economy farmers with a better health, nutrition and higher level individual and group selection - they had larger brains and bodies, were more rangy and progressive-mature than the tillers with just a low part of animal husbandry and weak individual-group selection.

Every investment must pay off and fact is, in a contraselective environment in which quantity and efficience is MUCH more important than quality and effectiveness reduced variants will flourish, at least in the masses, less so in the upper class and more valuable bloodlines of course.

Lulletje Rozewater
03-19-2010, 07:21 AM
Its all nutrition related. Today there are enough people around with bigger brains than those of Cro Magnon, yet they are a small minority and yes, brainsize is not everything.

But if considering that progressive-mature forms have both large brains and a highly effective body, the reason for their decline in numbers can never be effectiveness, but only additional factors, like those I usually describe with Alpinisation and Baltisation - partly probably sexual selection.

Reduction and Infantilisation is a response to a lack of energy and bad living conditions. Cro Magnon was also taller than farmers in medieval times were and the herders/mixed economy farmers with a better health, nutrition and higher level individual and group selection - they had larger brains and bodies, were more rangy and progressive-mature than the tillers with just a low part of animal husbandry and weak individual-group selection.

Every investment must pay off and fact is, in a contraselective environment in which quantity and efficience is MUCH more important than quality and effectiveness reduced variants will flourish, at least in the masses, less so in the upper class and more valuable bloodlines of course.


Nice.
Anatole France had a cc of about 950 and Einstein about 1700 cc

Agrippa
03-19-2010, 10:33 AM
Nice.
Anatole France had a cc of about 950 and Einstein about 1700 cc

I know myself that brainsize isnt as important as some people suggest, yet one could argue, somewhat ironic, just think Anatole France, if he really had that brainsize, would have had the same brain structure, but together with the size of Einstein :D

Its just one factor, like body height and bone robustness, of some importance and surely not the most important one, yet if those important factors show a significant decline, we might deal with a change and a deterioration which has to be explained and oh well, my explanation goes along the lines I have written above.

Additionally the decline is not as strong and what we might call the social higher strata usually, those which are high standing families and bloodlines which kept their standard over many generations.

And if you go through most countries, its clear that the most extreme decline can be observed among poor farmers, tillers quite often, which lived under the conditions described without balancing effects.

Lulletje Rozewater
03-20-2010, 01:53 PM
I know myself that brainsize isnt as important as some people suggest, yet one could argue, somewhat ironic, just think Anatole France, if he really had that brainsize, would have had the same brain structure, but together with the size of Einstein :D

Its just one factor, like body height and bone robustness, of some importance and surely not the most important one, yet if those important factors show a significant decline, we might deal with a change and a deterioration which has to be explained and oh well, my explanation goes along the lines I have written above.

Additionally the decline is not as strong and what we might call the social higher strata usually, those which are high standing families and bloodlines which kept their standard over many generations.

And if you go through most countries, its clear that the most extreme decline can be observed among poor farmers, tillers quite often, which lived under the conditions described without balancing effects.

Anatole had indeed that brain size.
Lucky he was not an Einstein.
We would all have been a French province by now.:eek:
I see the decline in all my travels and the deterioration is growing faster than expected.
Even from generation to generation.
It could be liberalism,it could be the mañana mañana attitude.
It certainly is TV education and as you mentioned-nutrition(poor farmers).
I believe that the random search for a mate(based on sex) is detrimental to a better offspring.
Could disease be an indication( In-breeding,Autism,Down-syndrome,Schizophrenia)
I looked once at a Liger(Lion and Tiger offspring).The Liger is bigger than both parents,but it suffers from a basket full of 'illnesses',including 'unlimited' body growth.

Agrippa
03-20-2010, 09:34 PM
I believe that the random search for a mate(based on sex) is detrimental to a better offspring.

The problem is rather that those couples which are a good match, both for themselves and the group, are more likely to use contraceptives and look for small, planned families than the negative and foreign ones. Thats part of the intraethnic and interethnic contraselection, Dysgenic trends, which only a Eugenic policy and/or changed organisation of and mentality in society could solve, best in combination.


Could disease be an indication( In-breeding,Autism,Down-syndrome,Schizophrenia)

Rather not. Down-syndrome is totally unrelated and Schizophrenia and Autism might be in some cases of that nature, but come usually from a combination of traits and environmental factors, of which some might be actually advantageous in some relatives, but detrimental in specific families and individuals.

Lulletje Rozewater
03-22-2010, 12:41 PM
I picked this up.

The complete classification description reads ; ANIMALIA- CHORDATA- VERTEBRATA- MAMMALIA- THERIA- PRIMATE- HOMINIDAE- HOMO-SAPIENS The most prominent difference between homo-sapiens and lower animals * WAS - our large highly developed brainHuman beings are scientifically identified from all other lifeforms by nine classifications. Those are Kingdom * Phylum- Subphylum -Class-Subclass- Order * Family - Genus- and Species

http://www.rense.com/general90/ignor.htm

Franz
03-26-2010, 04:31 AM
Nice.
Anatole France had a cc of about 950 and Einstein about 1700 cc

Your source? Einstein's brain weighed 1230g which is below the norm.

Several sources indicate he had a brain smaller than average. His parietal lobes were larger than average, and some have said his head was big compared to his body.

Lulletje Rozewater
03-26-2010, 07:56 AM
Your source? Einstein's brain weighed 1230g which is below the norm.

Several sources indicate he had a brain smaller than average. His parietal lobes were larger than average, and some have said his head was big compared to his body.

Franz, I remembered this from high school long time ago.
I must have been wrong on Einstein