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Don Matesz <[log in to unmask]>
Amadeus Schmidt <[log in to unmask]> wrote:
>
>Neanderthals had limited capabilities over 10thousands of years
>although - as long time ice age hunters - they should have had the
>very best access to the one (and only?) stuff that is used
>to build up brains (DHA and other w-3 fats).
No, they did not have "the very best access" to DHA. Only animals in the marine food
chain have the very best access to DHA, but Neanderthals did not eat fish!
>After that wild game is rather low in fat (mammouth too?) it is rather probable that they
*did* eat the fatty brain of the prey. And one brain should countain *all* what's
necessary to build up one brain, isn't it so?.>
No, land herbivores' brains do not have "all" the DHA required. Land herbivores have
rather small
brains which naturally contain only small amounts of DHA. For example a hippo's brain is
only .59 kg, an ox brain is only .45 kg, gorilla .40 kg, chimpanzee only .34 kg.
Compared to man, 1.5 kg and dophin 1.6 kg. One man's brain is 3 times the size of a
gorilla's, and nearly 5 times the size of a chimpanzee's, over twice the size of a hippo's
brain. The remarkable thing is the close absolute and relative size of human and dolphin
brains. The human brain is 2 per cent of body weight, the dophin is 1 percent.
Further, its not like you build a brain in the first two years of life and then you're all
done with it and no longer need any EFAs. The brain is in need of a continuous supply of
DHA throughout life. If you don't replenish the brain with EFAs on an ongoing basis,
throughout life, the nervous system degenerates at an unnecessarily rapid rate. This
may result in various adult onset neurological/behavioral disorders, as is well discussed
in The Omega Plan by Artemis Simopolous M.D.
>
>What you say, would imply that DHA was especially important for forebrain development.
Maybe--to produce a forebrain may require more DHA input--and other input not available on
the savannah. Here I don't think anyone has enough knowledge to say yes or no.
We must remember that in order for the forebrain to develop, the skull must develop in
concert to contain it. A Neanderthal type skull can't accomodate a modern human brain.
Since man does not differ from Neanderthal only in brain development but also in skull
shape, there have to be reasons for development of both differences at the same time
because a forebrain can't develop without a forehead. Further, that forebrain would be
useless unless at the same time there is development of the advanced peripheral nervous
system, and changes in the vascualr system to support the peripheral nerves, and changes
in glandular function and biochemistry to support all of it. Personally I think that this
kind of problem (need for simultaneous development of numerous new biochemical,
physiological and anatomical characteristics in the transition from one species to
another) presents great, if not insurmountable problems for a theory of evolution by
natural selection.
>Access to coastal fish and mussels may indeed be an important
>difference I have heard about iodide (not DHA) lack
>as a main problem for good ol' neanderthals.
>
>Later,in europe two big different cultures emerged (with agrigulture)
>megalith and linearband -- the latter without access to coast products.
>But no difference in brain size or shape is reported.
Was there trading? Most likely so--the inland people trade for fish and sea weeds all
over the world. In fact it was essential for access to iodine (important for preventing
cretinism) and DHA. Although there may be no difference in brain size or shape, there
may be difference in EFA contents of brain tissue and consequent differences in
intelligence or neurological health. It is well known that coastal people with high EFA
intakes have lower
rates of neurological diseases such as depression and MS compared to inland dwellers. In
land foods just aren't rich enough in the required EFAs.
>
>I wouldn't want to reject that aquatic theory although it doesn't
>seem to be much discussed among scientists.
>Coastal fish aren't the ones wtich are particularly rich in DHA
>-- and deep water fish we can't consider.
Why can't we consider deep water fish? Salmon aren't coastal fish, they are "deep water
fish" but they come to the coast regularly. It is the same for other species not only of
fish but of sea mammals carrying blubber rich in EFAs.
>Please mention what rejects savannah origin in your opinion
>(the 8 points).
First of all this is not my opinion alone, you seem to have missed that I was quoting Dr.
Michael Crawford, who is one of the world's leading reserachers in brain biochemistry and
EFAs. Dr. Crawford rejects the idea of a savannah origin. The idea that man originated
at the land-water interface, not on the grasslands, is supported by a set of features of
human anatomy, physiology, and behavior, some I learned from Dr. Crawford, some elsewhere:
1. Humans are not really fit for grassland life because they sweat profusely in high
heat, and require abundant water supplies as a result--but the grasslands are dry in the
summer, the time of the year that manıs need for water would be greatest. Human sweat
glands makes sense only if man evolved in a water-rich environment--such as at the
land-water interface.
2. Humans have lost most body hair--a trait shared with some aquatic mammals, whereas all
grasland animals are covered with hair.
3. At birth, man has an abundance of ³baby fat², and as an adult, man has subcutaneous
fat; this kind of fat is found in sea mammals but not in other primates nor grassland
animals in general.
4. The human nose is shaped in such a fashion that salt water is prevented from entering
during swimming and diving, unlike the noses of the vast majority of other land animals
and priamtes.
5. Humans are the only primates capable of producing tears, a characteristic that is
found in marine birds, crocodiles, and sea snakes.
6. Compared to other grassland animals, humans have an inferior sense of smell--but on
the grassland, a sense of smell is important.
7. Humans are the only land animal that is not an obligatory nose breather, due to the
fact that the larynx is connected to both the mouth and the nose; this adaptation also
makes speech possible.
8. Like other semi-aquatic animals, but unlike obligatory land animals, humans have a
natural diving reflex (the heart rate declines as soon as the head is submerged) and a
remarkable ability to swim, unlike grassland animals. Human infants can swim
spontaneously, with no instruction, at birth (and before six months of age). Adult humans
are capable of diving to a depth of 150 feet, and of swimming long distances, such as
accross the English Channel, without any equipment.
9. Examination of drowned humans finds that the amount of water aspired is small, due to
the fact that humans have a reflex spasm of the larynx--a reflex not foudn in strictly
land-based species.
10. Humans on land have a susceptibilty to degnerative joint diseases that may indicate
maladaptation to land-only life.
11. Humans love to be by water: They like to live and vacation by bodies of water, they
build pools and fountains in their yards and even in their homes, they go to great
expenses to have hot tubs, jacuzzis, and other pools of water at hand.
All of these points indicate that man is not really designed for a life of hunting and
gathering in the arid grasslands, and may have originated at the land-water interface.
Don
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