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View Full Version : A Quantitative Study of Australian Aboriginal and Caucasian Brains.



Pool Closer
Monday, September 5th, 2016, 06:32 AM
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1261675/


The brain volumes of 8 male Australian Aborigines and 11 male Caucasians were determined. Total brain volume was significantly smaller for Aborigines (1199 +/- 84 ml) compared to Caucasians (1386 +/- 98 ml). Significantly smaller volumes were also found for cerebellum, prosencephalon-mesencephalon unit, cerebral cortex, frontal cortex, parieto-occipitotemporal cortex, and hippocampus. Volumes of ponsmedulla oblongata unit (21 +/- 3 ml for Aborigines and 22 +/- 3 ml for Caucasians) and visual cortex (14.9 ml +/- 2.6 ml and 14.6 +/- 2.2 ml, respectively) did not differ significantly. The striate cortex extended further onto the lateral surface of the occipital lobe in Aboriginal brains. The frontal portion of cerebral cortex was larger in Aboriginal than in Caucasian brains. According to the specific growth periods for the areas studied, these differences could be explained by the higher incidence of malnutrition and infectious diseases for Aboriginals during the development of the brain in early childhood, especially after the 6th postnatal month. However, genetic influences cannot be excluded. The results for the visual cortex of Aborigines might represent an adaptation to living conditions in the bush and desert regions of Australia.

Interesting takeaways from this study:

Aboriginals who live in the bush are in better health than those who live in civilization

Aboriginals score higher than Australian Whites on tests related to visual intelligence. It seems that everyone east of West Eurasia scores higher on tests related to vision and lower on verbal reasoning, while in most of West Eurasia, the exact opposite is the case.

Shadow
Monday, September 19th, 2016, 12:06 AM
OK, so this is anatomy, really a division of medicine or at least something medical people envelope themselves with. My point is that it is not anthropology. Let's look at a couple differences.

Always when using medical literature for anthropological work the very first thing to look at is sample size. Here it is 8 for Aborigines and 11 for Caucasians. This is tiny in terms of sample size.

The second thing with stands out is the actual brain size figures and the +/- figures. For Aborigines +/- 84 ml. For Caucasians +/- 98 ml. Hell, the variation for Caucasians is almost one liter. Both these figures are huge.

Taken together, small sample size and large deviations from the mean probably indicates the samples have no statistical significance. This is a big deal in anthropology and means "you are just eyeballing".

This does not mean they are wrong, however, it is just not scientific to draw population/racial conclusions about this sample.

Here is what interests me:

The frontal portion of cerebral cortex was larger in Aboriginal than in Caucasian brains.

_______________________

The frontal region of the hobbits contained a sulcus, a valley, between the two hemispheres and a small growth area extending to the front on both opposing lobes. This may indicate intelligence, more intelligence than would be expected from such a small brain as the hobbits had. Sometimes this is also seen in East Asians. Did East Asians get this from the hobbits? Here again we see a large frontal cortex in Aborigines. This study was done in 1987 before the hobbits came to light but it would be interesting to see how these Aborigines matched up with the hobbits.

Catterick
Monday, September 19th, 2016, 08:04 AM
European brains are structurally odd in a way leaning to neanderthals. One effect of this is we are less inclined to suffer travelsickness.

Shadow
Tuesday, September 20th, 2016, 03:40 AM
European brains are structurally odd in a way leaning to neanderthals. One effect of this is we are less inclined to suffer travelsickness.

You know I'm going to want to know more about this. Any references?

Catterick
Tuesday, September 20th, 2016, 08:11 AM
You know I'm going to want to know more about this. Any references?

Bruner's blog?

Shadow
Tuesday, September 20th, 2016, 09:11 PM
Bruner's blog?

I found this little bit:

http://digg.com/2015/its-not-your-fault-you-get-motion-sickness