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The largest analysis of the genomic diversity of African hunter-gatherer populations reveals that modern humans likely originated in southern Africa, rather than eastern Africa as is generally assumed. This study provides the clearest idea yet of where modern humans originated.
About 60,000 years ago, modern humans left Africa and began the spread to other regions of the world. But the great genetic diversity of African populations made it hard to accurately predict where in Africa humans might have originated. Now, a team led by postdoctoral scholar in genetics Brenna Henn, PhD, and biology professor Marcus Feldman, PhD, has found that modern humans likely originated in southern Africa. To reach this conclusion, the researchers analyzed the largest dataset to date for hunter-gatherer populations. The study was published online March 7 in the Proceedings of the National Academy of Sciences.
“Our belief used to be that the center of humans leaving Africa was in east Africa. This paper focuses attention on southern Africa, and in particular a group of hunter-gatherers, the Bushmen, who speak one of the Khoisan languages,” said Feldman. These languages are characterized by the presence of “click” sounds.
Africa has been inferred to be the continent of origin for all modern human populations, with the earliest modern-human skulls having been discovered in east Africa. In addition, populations outside Africa contain a subset of the genetic diversity found there. As modern humans moved eastward, the level of variation decreased, reaching its minimum in the Americas. But the details of genetic evolution within Africa have remained hazy.
This is mainly because African populations are some of the most genetically diverse in the world. A lack of sufficient genetic samples, especially from the hunter-gatherer populations, made it hard to infer much about early human evolutionary history. “We’ve just never had enough people represented in our studies before,” Feldman said. “Without the participation of these people, patterns of evolution within Africa can’t be determined,” he said.
The current study provides “a much more satisfying answer,” said Feldman. “We just didn’t have as much DNA data earlier,” he said. Before this study, only a handful of Namibian Khoisan-speakers had been compared with other Africans. To get an accurate picture, the researchers needed to compare the genetics of different hunter-gatherer populations, as well as individuals within each population, at hundreds of thousands of sites in the DNA. According to Feldman, the researchers needed the participation of more Bushmen, and Henn, the paper’s first author, accomplished this.
The scientists analyzed variations in the individual nucleotide bases that make up DNA. They genotyped 650,000 such individual changes or “single-nucleotide polymorphisms” in people from 25 African populations. Apart from the click-speaking hunter-gatherer populations from South Africa and Tanzania, they also studied Pygmies and 21 agriculturalist populations. Statistical analysis showed that the Bushmen had the greatest genetic variation and are most likely to be the source population from which all other African populations diverged.
Different genetic variants contain different combinations of genes, which can be thought of as a single string. Genetic recombination breaks these strings into smaller segments. The older the population, the shorter the segments and the greater the genetic variation. It was already known that the most variation and hence shortest segments occurred in Africa. The new study found that within Africa, the Bushmen have the shortest segments, and segment length increases as one moves from south to north.
More than 5,000 years ago, sub-Saharan Africa was populated mainly by linguistically and culturally diverse hunter-gatherer populations. Since then, most of these populations have either gone extinct or turned to agriculture and pastoral living, leaving only the Pygmies in central Africa, a click-speaking tribe of Tanzania, the Hadza, and southern African Bushmen, as the last hunter-gatherers.
“The paper is also fascinating in that some hunter-gatherer groups have never mixed with their neighbors,” said Feldman. “The mystery is whether there ever was a connection between the different click-speaking peoples in the past. Brenna and the team have shown that if such a connection ever existed, it was long before the invention of agriculture.”
As evidence of the uniqueness of some of these populations, the researchers found that certain immune system proteins that appear almost nowhere else on Earth occurred at a higher frequency in one hunter-gatherer group. The scientists also found signs of natural selection related to genes involved in immune response and protection against pathogens.
Henn and Julie Granka, a graduate student in biology, recently revisited the South African Bushmen who participated in the study and took height and skin color measurements from the people whose DNA they had analyzed. “We will be collaborating with several South African scholars to look at such phenotypes in more detail,” Feldman said.
According to Feldman, despite large ongoing projects researchers still don’t know enough about human variation. “Not enough populations around the world have been studied,” he said. For example, “We don’t know much about Australian Aboriginals, indigenous Americans or South Asian people, who comprise nearly a sixth of the world’s population,” he said.
Feldman and other researchers working with the Human Genome Diversity Project, based at Centre d’Étude du Polymorphisme Humain in Paris, hope to engage other populations in the search for their evolutionary ancestry. “There are lots of evolutionary problems to be solved,” he said. “Analysis of DNA is our best chance to solve them.”
Genetics professor Carlos Bustamante, PhD, and postdoctoral scholar Jeffrey Kidd, PhD, are co-authors on the study, funded by the Center for Human Origins and Evolution, the Morrison Institute for Population and Resource Studies at Stanford, a UCSF Chancellor’s Graduate Research Fellowship and the National Institutes of Health.
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posted
^I think this is a theory worth considering because the San demonstrate phenotypes that could easily evolve into the modern variations of Mongols and European Albinos that we see today.
Accepting the San as the first Humans also allows for easy explanation of African skin colors.
The UV index of South Africa reaches the maximum of eleven in only 4 to 6 months of the year. Therefore "Brown Skin" provides ample protection.
But to the north at the Equator, the UV index is a CONSTANT max. of 11 all year long.
There, the Blackest skin possible would be necessary to protect humans from the Sun.
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^That leaves just one more thing to be explained:
Straight Hair.
Previously we have seen that Albinism (defective "P" gene) actually straightens the hair.
And we have also seen that the effects of a defective "P" gene are not always universal. Thus a person with a defective "P" gene might only have it effect the EYES.
Or only the HAIR:
And of course, when the effects of a defective "P" gene ARE universal, we get the Central Asian Albino.
Accepting the San as the first Humans also allows for easy explanation of African skin colors.
The UV index of South Africa reaches the maximum of eleven in only 4 to 6 months of the year. Therefore "Brown Skin" provides ample protection.
But to the north at the Equator, the UV index is a CONSTANT max. of 11 all year long.
There, the Blackest skin possible would be necessary to protect humans from the Sun.
^^^ yes good analysis
_____________________________________________ .
^^^ I question this.
I was not able to find a reputable non-tabloid article in published media that confirms the couple was genetically tested. Not to brush all Nigerians, but some are famous for scams.
Do you have any more reputable sources for this story? It seems to have magically disappeared. You would think by now scientists would have published a detailed study. I don't buy it, the Sun's not reputable. Look at the girl's expression on the left, she like, "why are my parents putting me up to this?"
^^ features very un-European looking somewhat Asian however
Posts: 42919 | From: , | Registered: Jan 2010
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posted
Mike cut the Albino Central Asian crap stupid White people hating, history stealing, lying, White people genocidist, Black racist, Black supremacist son of satan. Whites are NOT Albinos NOR are we Asians.
Posts: 3257 | From: Madisonville, KY USA | Registered: Nov 2011
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quote:Originally posted by Mike111: [QB] ^That leaves just one more thing to be explained:
Straight Hair.
Previously we have seen that Albinism (defective "P" gene) actually straightens the hair.
This couple has distant 'white' ancestry. Its just a rare recombination of genes from a distant white ancestor, which has produced those features. The original report in the newspaper, explicity notes of the distant white ancestry, and how one side of the family had a legend of a "fair-skinned" ancestor. Yet the Afronut liars, never take note of it.
Furthermore, also note that this can happen vice-versa, for example Sandra Liang.
When you say someone has "white heritage" or "distant White ancestry", what you are really stating is, they are OCA (albinism) carriers.
Since Albinism and the mutation resulting in the OCA gene began with African Negroes (probably In The San), what are you really stating, that the chicken comes before the egg?
Mike, good analysis. I've come to the same conclusion about the San and their being ancestors and gateways to morphing into the various "sub-races".
Good picture showing "normal" White person, who is actually an clinical Albino. Her cock-eyed-ness (as well as Skin, Hair, and eye color) is actually a MAJOR clinical symptom of Albinism; strabismus.
Vision Signs and symptoms of albinism related to eye function include:
Rapid, involuntary back-and-forth movement of the eyes (nystagmus)
Inability of both eyes to stay directed at the same point or to move in unison (strabismus)
Extreme nearsightedness or farsightedness Sensitivity to light (photophobia)
Astigmatism
If MELANIN could be packaged and sold to Albinos, it would be worth an once of platinum per gram, and they'd PAY!
Posts: 4693 | From: Saturn | Registered: Apr 2012
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The Nigerian baby has been test genetically, and he is completely Nigerian, without foreign ancestry.
quote:Originally posted by Anglo_Pisspot:
quote:Originally posted by Mike111: [QB] ^That leaves just one more thing to be explained:
Straight Hair.
Previously we have seen that Albinism (defective "P" gene) actually straightens the hair.
This couple has distant 'white' ancestry. Its just a rare recombination of genes from a distant white ancestor, which has produced those features. The original report in the newspaper, explicity notes of the distant white ancestry, and how one side of the family had a legend of a "fair-skinned" ancestor. Yet the Afronut liars, never take note of it.
Furthermore, also note that this can happen vice-versa, for example Sandra Liang.
"Sandra Laing was born black, but to white parents"
lol at this fake university student with extremely low comprehension skills. See, attending a student forum doesn't make you a university student.
quote: By a biological quirk, the pigment of an unknown black ancestor had lain dormant for generations and manifested in Sandra. Genetic throwbacks were not unheard of but if there was ever a wrong place and wrong time for this phenomenon, it was apartheid South Africa.
Atavism!!
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
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quote:Originally posted by Troll Patrol: lol at this fact university student with extrmely low comprehension skills. See attending a student forum doesn't make you a university student.
One of the Major defects of the Albino "learning" model is the ignorant belief that anyone can be trained to perform any task. This is systematic of overall defective group thinking. Not every person is gifted to be a painter, researcher or engineer, no matter how many class room hours they accumulate.
A_P, DHDoxie and Cass serve as perfect examples of this flawed indoctrination model. Each exhibit more of the intelligence meant for being minimally qualified guided technicians versus free thinking engineer/scientists.
One or both of these children are OCA carriers. Either has the potential of birthing Albinos, ESPECIALLY true if either mates with a "white" (Albino) person. and the beat goes on..... Posts: 4693 | From: Saturn | Registered: Apr 2012
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What is the latest to that "white" Nigerian baby. Has the phenotype changed? Liarness? Can you dig that up and post?
Reason. My son was born as light as that baby. Couldn't tell apart from the pure white babies. Now he is darker than my daughter. Granted my wife is light skin. Point is, many babies are born depigmented with "softer " hair.
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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^I'm having a hard time deciding who is the funniest (read pathetic), Albinos or Negroes.
Around the world, Black women drop Albino babies every Minute of the day.
.
Yet those Albinos in Britain treat this "Normal" occurrence as something that is somehow unique. Do you really need to be a genius to understand that they are trying to draw attention away from the obvious comparison between that Albino baby and themselves?
Black people chuckle at it, Negroes take it seriously.
The other day, I heard an Albino allude to racism being a bad thing.
No it's not!
Being in a mental condition where you have convinced yourself, and Negroes, that having a defect "P" gene is a good thing, even an indicator of superiority, is not bad, It's delusional and stupid.
Black people chuckle at it, Negroes take it seriously.
Posts: 22721 | Registered: Oct 2005
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quote:Originally posted by xyyman: [QB] What is the latest to that "white" Nigerian baby. Has the phenotype changed? Can you dig that up and post?
there's nothing to dig up this was a hoax published in a tabloid
quote:Originally posted by xyyman:. My son was born as light as that baby. Couldn't tell apart from the pure white babies. Now he is darker than my daughter. Granted my wife is light skin. Point is, many babies are born depigmented with "softer " hair.
"granted my wife is light skinned"
Granted neither of these Nigerians have light skin. There is no record of genetic testing. The story has been dead for quite some time now. Reason: it's a scam and I will put money on it. When people make these claims tabloids are not intersted in verifying the claim. They are interested in selling newspapers. This story is baloney made out of rat meat
quote:Originally posted by Mike111: ^I'm having a hard time deciding who is the funniest (read pathetic), Albinos or Negroes.
Around the world, Black women drop Albino babies every Minute of the day.
.
Yet those Albinos in Britain treat this "Normal" occurrence as something that is somehow unique. Do you really need to be a genius to understand that they are trying to draw attention away from the obvious comparison between that Albino baby and themselves?
Black people chuckle at it, Negroes take it seriously.
The other day, I heard an Albino allude to racism being a bad thing.
No it's not!
Being in a mental condition where you have convinced yourself, and Negroes, that having a defect "P" gene is a good thing, even an indicator of superiority, is not bad, It's delusional and stupid.
Black people chuckle at it, Negroes take it seriously.
What happens when the Albinos delusions are exposed?
They go CRAZY!
Whatever your opinion of Obama, he is clearly in a class by himself when compared to those Albinos in power.
Recognizing this, the "Low" type Albinos react with anger and hatred, because they understand that he is clearly superior to them.
Controversial country star Hank Williams Jr., who caused a stir last year when he compared Barack Obama to Hitler, is at it again.
At the Iowa State Fair, Williams bashed Obama to a crowd saying, "We've got a Muslim president who hates farming, hates the military, hates the U.S. and we hate him!"
To make his anti-Obama message known, Williams recently released a 10-disc album titled "Old School, New Rules." There is no subtlety in the country star's politically charged song lyrics that blatantly boast "Hey Barack, pack your bags, head to Chicago, take your teleprompter with you so you'll know where to go."
posted
Great post Mike. But archaeologists have long recognized a Southern African origin for anatomically modern humans since they discovered Grimaldi man.
.
-------------------- C. A. Winters Posts: 13012 | From: Chicago | Registered: Jan 2006
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-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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posted
I beleive the San people are the ancester of the mongoloid yellow Asian subspecies. The straight hair of the Asian maybe due to selective breeding . Black parents have Albino children all the time .In the case of pale skin European parents having a black children my opinion is those pale skin parents are not realy white they are bleach black peoples.Those people are the original black Europeans who mixed with the pale central Asian invaders .There are country in Europe who use to be inhabited by black people now they are inhabited by pale people .The black people in those countries just bleached out if you check their DNA it is black people DNA. Hank William Jr is a psychopatic racist ignorant redneck who doesnt like a black person in a powerful place even thought President Barack Obama is doing a great job for the white elite system .I blame albino academia who dont want to teach the real history of the world even at the university level.They do not teach that black people originated civilization,science and religion.They do not teach that all the world first civilization were black and all the ancient God of the world were black .Albino academia want to maintain the ignorant racist ideology to discriminate against black people .
That couple are clearly not Negroid, but mixed race. Even as the article itself opens:
"The girls, whose parents are mixed-race, just celebrated their 7th birthday together"
Their parents are not "Black", but mixed. They look mostly Mestizo admixed, with a weak Negroid component. The guy pictured claims his dad is Spanish (white).
But you Afrocentric trolls think anyone "with a tan" = black so i'm wasting my time...
Posts: 1575 | From: - | Registered: May 2011
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QUOTE: "I beleive the San people are the ancester of the mongoloid yellow Asian subspecies" ****sighhhhh****
BTW – to Mike’s point. Africans living south of the Sahara have the greatest variety and shades of skin color see Relethord et al.
Also- the head line is old news. S. Tishkoff pointed that out, and so did Heather Norton. I am going offend the Albino Theorist….again. Read enough and you will realize that it is not as simplistic. Light(not white) skin is ancestral….and may be the first AMH were the same shade as the San( Norton et al) That would explain the phenomenon of Jamaican Red Igbos, or Trinidadian sugar heads and some AA yellow bone…..and Nigerains with red hair(and blue eyes).
All studies available at ESR.
At the same explanation exist for straight hair….. That is why Andaman Islanders, Papua new Guineans have kinky hair while populations further north have straight hair.
Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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That couple are clearly not Negroid, but mixed race. Even as the article itself opens:
"The girls, whose parents are mixed-race, just celebrated their 7th birthday together"
Their parents are not "Black", but mixed. They look mostly Mestizo admixed, with a weak Negroid component. The guy pictured claims his dad is Spanish (white).
But you Afrocentric trolls think anyone "with a tan" = black so i'm wasting my time... [/QB]
LOL AT THIS PISSPOT, CALLING POEPLE DUMB !!!!!LOL
I KNOW THEY ARE MIXED, THIS IS WHY I POSTED THIS PICTURE IN THE FIRST PLACE, YOU RETARD!!!!!!
You have low comprehension skills, and it shows on many levels. LOOOOOOOOL
Both parents of are mixed-black, these two girls, are of black-British mixed ancestry. Which would make them technically MULAT, NOT MESTIZO, YOU DUMBO!
quote:A mixed-race British mom gave birth to twins recently - one of each. Not a boy and a girl. Two girls - one black, the other white. The odds of such a birth are about a million to one, experts said. It was a shock when I realized that my twins were two different colors," Kylie Hodgson, 19, told London's Daily Mail. "But it doesn't matter to us - they are just our two gorgeous little girls."
Commentary: In early March 2006 an email complete with photographs of adorable twin girls - one black skinned and one white - began circulating. The message states that the twins are the children of a mixed race British couple and claims the chances of such a birth are "about a million to one".
The information in the email is true and the photographs are genuine. The photographs depict fair-skinned Remee and dark-skinned Kian who were born in April 2005. The fraternal twins were born to parents Kylie Hodgson and Remi Horder from Nottingham, England. Both Kylie and Remi are of mixed race, with black fathers and white mothers.
Although exceedingly rare, such births are not unprecedented. An article about the twins in the Daily Mail explains that:
If a woman is of mixed race, her eggs will usually contain a mixture of genes coding for both black and white skin.
Similarly, a man of mixed race will have a variety of different genes in his sperm. When these eggs and sperm come together, they will create a baby of mixed race. But, very occasionally, the egg or sperm might contain genes coding for one skin colour. If both the egg and sperm contain all white genes, the baby will be white. And if both contain just the versions necessary for black skin, the baby will be black.
For a mixed-race couple, the odds of either of these scenarios is around 100 to one. But both scenarios can occur at the same time if the woman conceives non-identical twins, another 100 to one chance.
This involves two eggs being fertilised by two sperm at the same time, which also has odds of around 100 to one.
If a sperm containing all-white genes fuses with a similar egg and a sperm coding for purely black skin fuses with a similar egg, two babies of dramatically different colours will be born.
The odds of this happening are 100 x 100 x 100 - a million to one.
posted
^ Very sad desperate attempt at recovery, despite the fact you post a link/title entitled "blacknwhitetwins" despite NEITHER of their parents are "Black", but mixed.
Posts: 1575 | From: - | Registered: May 2011
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quote:Originally posted by Anglo_Pyramidologist: ^ Very sad desperate attempt at recovery, despite the fact you post a link/title entitled "blacknwhitetwins" despite NEITHER of their parents are "Black", but mixed.
Atavism!!!!!!!!!!!!!!!!! Dude you are DUMB. ATAVISM !!!!
If you are so convinced about your rant, you always can go to South London. And give them your little soapbox speech. I will read in the newspaper how it ended.
Posts: 22234 | From: האם אינכם כילדי הכרית אלי בני ישראל | Registered: Nov 2010
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^Anyway, back to the subject of the matter.
quote:Originally posted by Clyde Winters: Great post Mike. But archaeologists have long recognized a Southern African origin for anatomically modern humans since they discovered Grimaldi man.
.
quote:A handful of the world's great cities trace their heritage to early human settlements thousands of years back. Johannesburg's earliest residents were in the neighbourhood 3million years ago.
Forty kilometres west of the city, among nondescript koppies, scattered shrubs and trees, is a 47 000hectare valley known as the Cradle of Humankind.
Three million years of human activity have taken place in and around these caves, including people's earliestknown mastery of fire, and 40% of all the world's human ancestor fossils have been found here. The biggest and bestknown of the caves is Sterkfontein, where over 500 hominid fossils and over 9 000 stone tools have been found. It was at Sterkfontein that two major finds were made, that have changed modern paleontology:
The Australopithecus africanus Mrs Ples (now believed to be a Mister Ples), dating back 2.5million years, and found by Robert Bloom in 1947. Little Foot, an almost complete apeman skeleton that could be just over 4 million years old, the first pieces footbones of which were found by Ronald Clarke and Phillip Tobias in 1995 (the bones had lain in a box since the late 1970s, when they were excavated).
In 1997, Clarke, digging through more boxes of bones from Sterkfontein, found more footbones from the same individual one with a clean break suggesting that more of Little Foot's bones might still be inside the cave. Clarke went after the rest of Little Foot's skeleton and in 1998, amazingly, found it, or at least a significant part of it.
A complete skull and fragments of arm, foot and leg bones have been uncovered so far; the rest of the bones are still being painstakingly excavated from the rock.
Some believe that Little Foot is the most significant hominid find since Raymond Dart's discovery of the skull of the Taung child, a juvenile Australopithecus africanus, discovered in 1924 near a town called Taung in the far north of North West.
According to Clarke, the Little Foot fossil has yielded the most complete australopithecine skull yet found, found together with the most complete set of foot and leg bones known so far with more extracted from the rock since then. In addition, the preservation of the skeleton is extraordinary, with most of the bones intact and joined in their natural position.
The Little Foot skeleton was originally thought to be between 3 and 3.5 million years old, but a more recent study argues that it could be over 4 million years old, which would make it one of the oldest known australopithecine fossils, and easily the oldest from South Africa.
According to Talk.origins: "If Clarke's expectations of further finds are borne out, Little Foot could become the most spectacular and important hominid fossil ever discovered, rivalled only by the Turkana Boy Homo erectus skeleton [discovered in 1984 near Lake Turkana in Kenya]." The Sterkfontein valley consists of around 40 different fossil sites, 13 of which have been excavated.
It includes Bolt's Farm, where the remains of three sabretooth cats have been found in a pit that trapped animals; Swartkrans, site of the earliestknown deliberate use of fire, around 1.3million years ago; Haasgat, where the fossils of early forestdwelling monkeys, around 1.3million years old, were found; and Gondolin, where 90 000 fossil specimens have been found since 1979.
The area was declared a World Heritage Site in 1999. Although it is on privately owned land, any finds belong to the world, and the it is on privately owned land, any finds belong to the world, and the area is strictly controlled and protected.
Beginnings
In the late 1890s, miners dynamited the Sterkfontein caves, searching for limestone which they converted into quick lime, an element needed for the processing of gold and the manufacture of cement. They displaced the sediment and revealed entrances to the caves.
The rocks contain cyclindrical shapes - evidence of early life called stromatolite, dating back 3.8-billion years. These organisms breathed in carbon dioxide and breathed out oxygen, thus increasing the earth's oxygen levels and leading to the evolution of other forms of life.
Some 2.5-billion years ago, the area was an inland shallow sea. Over time the water evaporated and the mud formed dolomite rock, in which the stromatolite are visible.
Around 2-billion years ago a large meteorite, 10 kilometres in diameter, fell in Vredefort (100 kilometres south of Sterkfontein), leaving a massive crater now known as the Vredefort Dome. The entire area for hundreds of kilometres around was covered in debris, which helped preserve the gold reefs of the Witwatersrand, preventing them from being eroded - and also helped preserve the stromatolite rocks.
Some 3.5-million years ago, openings to the caves started appearing. They may have been occupied by sabre-toothed cats and other predators which would explain why the remains of large herbivores like wildebeest, extinct zebra and buffalo have been found in the caves.
One of the caves is called Plover's Lake Cave. It has been explored some 50 metres down, but beyond that point are a labyrinth of unexplored passages, and several entrances. A hyena and a porcupine are known to live there - no-one has spotted them, but their footprints are often seen. Excavations of Plover Cave and others in the area is ongoing.
The nearby Wonder Cave has an enormous chamber with beautiful 15 metre-high stalactite formations. The Cave is believed to be 2.2-million years old, and bones of rodents, frogs, lizards and birds have been found in the cave.
It's hard while walking around the area to fully comprehend the age of the sites and the importance of the finds. Charles Darwin predicted in the 19th Century that the origins of humankind would be traced back to Africa because that's where the great apes live.
South Africans, and Jo'burgers in particular, don't have far to go to take a stroll into life millions of years ago ... so long as they are mindful of hyenas and porcupines.
posted
^ In the above illustration, the melanosome may be viewed initially (nearest to nucleus) as a newly produced empty container. The container is then filled with first Phaoemelanin using naturally recurring Cysteine levels as the switching trigger controlling either Phaoemelanin or Eumelanin production.
As long as Cysteine, a sulfur-containing amino acid is present in the system, only phaoemelanin is produced. Cysteine is available from foods (eggs, chicken, broccoli, etc.), but is also naturally produced in the body. Normally, the supply is adequate to produce an approximate 20-30% ratio of Phaeomelanin to Eumelanin production. In Albinos, there exists an exceedingly high supply of Cysteine thus avoiding phaoemelanin to Eumelanin crossover producing very little Eumelanin content. In summary, Eumelanin production is inhibited until all Cysteine in the system is exhausted. Once all Cysteine supply is used up, conversion of Eumelanin begins.
-------------------- Selenium gives real life and true reality Posts: 4693 | From: Saturn | Registered: Apr 2012
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so i'm wasting my time...
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