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Research confirms theory that all modern humans descended from the same small group of people

Researchers have produced new DNA evidence that almost certainly confirms the theory that all modern humans have a common ancestry.
The genetic survey, produced by a collaborative team led by scholars at Cambridge and Anglia Ruskin Universities, shows that Australia's aboriginal population sprang from the same tiny group of colonists, along with their New Guinean neighbours.

The research confirms the “Out Of Africa” hypothesis that all modern humans stem from a single group of Homo sapiens who emigrated from Africa 2,000 generations ago and spread throughout Eurasia over thousands of years. These settlers replaced other early humans (such as Neanderthals), rather than interbreeding with them.

Academics analysed the mitochondrial DNA (mtDNA) and Y chromosome DNA of Aboriginal Australians and Melanesians from New Guinea. This data was compared with the various DNA patterns associated with early humans. The research was an international effort, with researchers from Tartu in Estonia, Oxford, and Stanford in California all contributing key data and expertise.

The results showed that both the Aborigines and Melanesians share the genetic features that have been linked to the exodus of modern humans from Africa 50,000 years ago.

Until now, one of the main reasons for doubting the “Out Of Africa” theory was the existence of inconsistent evidence in Australia. The skeletal and tool remains that have been found there are strikingly different from those elsewhere on the “coastal expressway” – the route through South Asia taken by the early settlers.

Some scholars argue that these discrepancies exist either because the early colonists interbred with the local Homo erectus population, or because there was a subsequent, secondary migration from Africa. Both explanations would undermine the theory of a single, common origin for modern-day humans.

But in the latest research there was no evidence of a genetic inheritance from Homo erectus, indicating that the settlers did not mix and that these people therefore share the same direct ancestry as the other Eurasian peoples.

Geneticist Dr Peter Forster, who led the research, said: “Although it has been speculated that the populations of Australia and New Guinea came from the same ancestors, the fossil record differs so significantly it has been difficult to prove. For the first time, this evidence gives us a genetic link showing that the Australian Aboriginal and New Guinean populations are descended directly from the same specific group of people who emerged from the African migration.”

At the time of the migration, 50,000 years ago, Australia and New Guinea were joined by a land bridge and the region was also only separated from the main Eurasian land mass by narrow straits such as Wallaces Line in Indonesia. The land bridge was submerged about 8,000 years ago.

The new study also explains why the fossil and archaeological record in Australia is so different to that found elsewhere even though the genetic record shows no evidence of interbreeding with Homo erectus, and indicates a single Palaeolithic colonisation event.

The DNA patterns of the Australian and Melanesian populations show that the population evolved in relative isolation. The two groups also share certain genetic characteristics that are not found beyond Melanesia. This would suggest that there was very little gene flow into Australia after the original migration.

Dr Toomas Kivisild, from the Cambridge University Department of Biological Anthropology, who co-authored the report, said: “The evidence points to relative isolation after the initial arrival, which would mean any significant developments in skeletal form and tool use were not influenced by outside sources.

“There was probably a minor secondary gene flow into Australia while the land bridge from New Guinea was still open, but once it was submerged the population was apparently isolated for thousands of years. The differences in the archaeological record are probably the result of this, rather than any secondary migration or interbreeding.”

The study is reported in the new issue of Proceedings of the National Academy of Sciences.

Homo sapiens originated in Africa 150,000 years ago and began to migrate 55,000 to 60,000 years ago. It is thought he arrived in Australia around 45,000 years before present (BP). Australia was, at the time, already colonised by homo erectus. The eastern migration route towards Australia is referred to as the “coastal express” route, due to the comparatively rapid progress made by those who used it. This dispersal, from Africa to Australia through Arabia, Asia and the Malay peninsula, could have occurred at a rate of 1km per year.

Australia's archaeological record provides several apparent inconsistencies with the “Out Of Africa” theory. In particular, the earliest known Australian skeletons, from Lake Mungo, are relatively slender and gracile in form, whereas younger skeletal finds are much more robust. This robustness, which remains, for example, in the brow ridge structure of modern Aborigines, would suggest either interbreeding between homo sapiens and homo erectus or multiple migrations into Australia, followed by interbreeding. The archaeological data also indicates an intensification of the density and complexity of different stone tools in Australia during the Holocene period (beginning around 10,000 years BP), in particular the emergence of backed-blade stone technology. The first dingos arrived at around the same time, and it is thought both were brought to the continent by new human arrivals – leading to theories of a secondary migration that has resulted in disputes regarding the single point of origin theory.

Source: University of Cambridge

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Hmmmm? Digesting this, might take a few days.

Way cool Mike.
I look forward to many days of thought (much as over the past few hours) on this Topic.

~~Later!

"...the earliest known Australian skeletons, from Lake Mungo, are relatively slender and gracile in form, whereas younger skeletal finds are much more robust. This robustness, which remains, for example, in the brow ridge structure of modern Aborigines, would suggest either interbreeding between homo sapiens and homo erectus or multiple migrations into Australia, followed by interbreeding."

Has anyone considered the idea of this 'robustness' simply being a response to the environment; an adaptation (which happens to be somewhat of a reversion to a previous physiognomy). It's a mechanism that is not uncommon, check out sticklebacks:
http://whyfiles.org/shorties/095fish_evol/index.html


"The first dingos arrived at around the same time, and it is thought both were brought to the continent by new human arrivals - leading to theories of a secondary migration that has resulted in disputes regarding the single point of origin theory."

Dogs seem to have originated in Western China/Siberia area; just north of SE Asia. Has anyone thought about trade and commerce over the land bridge? It doesn't have to be just "immigration."

"If dogs originated about 12-14,000 years ago, they must have spread across several continents in a relatively short period of time."
http://canidae.ca/dog.htm
...and from the same site: "After six generations of breeding only tame foxes, a new class, Class IE, ("domesticated elite") had to be added. These foxes were very dog-like and actively sought out human attention and would lick experimenters and wag their tails like dogs. After twenty generations, 35% of the experimental foxes were domesticated elite and today, 70-80% of the foxes are."
...and they don't really mean "tame" foxes; they mean "least aggressive," captive foxes.


...also interesting....
"The evidence for the development of discrete dog varieties in North America includes an in-depth account of the little-known Salish Wool dog of the central Northwest Coast (NWC), which may be the only true breed (as defined by modern standards) developed prehistorically in the Americas."
http://www.vin.com/proceedings/Proceedings.plx?CID=WSAVA2005&PID=11071&O=Generic


Just the remarkable plasticity of expression in the canine genome should clue us into the idea that there are many evolutionary mechanism that we don't understand yet.

~~SA

Hey Mike,
Don't miss my questions above, but do you have any citation for that PNAS article? I couldn't find anything in PNAS on this (up to the May 8 issue).
Could it be May 15?

I did find a link to Toomas Kivisild, but not Peter Forster.

A prehistory of Indian Y chromosomes: Evaluating demic diffusion scenarios. by et al. (incl. Toomas Kivisild)

Understanding the genetic origins and demographic history of Indian populations is important both for questions concerning the early settlement of Eurasia and more recent events, including the appearance of Indo-Aryan languages and settled agriculture in the subcontinent. .... The sharing of some Y-chromosomal haplogroups between Indian and Central Asian populations is most parsimoniously explained by a deep, common ancestry between the two regions, with diffusion of some Indian-specific lineages northward. The Y-chromosomal data consistently suggest a largely South Asian origin for Indian caste communities and therefore argue against any major influx, from regions north and west of India, of people associated either with the development of agriculture or the spread of the Indo-Aryan language family....
PNAS | January 24, 2006 | vol. 103 | no. 4 | 843-848
...just a curiosity...not related.

Thanks
~SA
p.s. I really liked this link from my questions above.
http://canidae.ca/dog.htm

Mike, no-one has ever doubted that Australia and New Guinea have been isolated for a long time and are closer to each other genetically than either is to other humans. But there are one or two inconsistencies in your original post. For example, "Australia was, at the time, already colonised by homo erectus". Homo erectus has never been found in Australia. The research fails to explain several anomolies. Such as:

"The skeletal and tool remains that have been found there are strikingly different from those elsewhere on the “coastal expressway” – the route through South Asia taken by the early settlers." "The earliest known Australian skeletons, from Lake Mungo, are relatively slender and gracile in form, whereas younger skeletal finds are much more robust". "The evidence points to relative isolation after the initial arrival, which would mean any significant developments in skeletal form and tool use were not influenced by outside sources". But later in the article, "it is thought both were brought to the continent by new human arrivals". But earlier change was not brought in by new arrivals? How can they tell?


The researchers say:

"there was no evidence of a genetic inheritance from Homo erectus".

But they only looked at Y-chromosome and mtDNA. Just two genes out of the 40,000 or so we have.

"...at Y-chromosome and mtDNA. Just two genes out of the 40,000 or so we have." -ttnz
Terry, you're mixing metaphors (chromosomes & genes). I'd think it was more like 1 or 2 out of ~50.

What about my above questions on post #21471, "...considered the idea of this 'robustness' simply being a response to the environment?"

If my memory is correct, a 0.1% adaptive advantage can spread to 95% of the population after about 100 generations; and a 0.5% advantage takes only 20 generations to spread like that.

Also, I think our ideas of "immigration" may be too limited. We spread (well, the fitter ones did) and we traded; but I doubt there was much casual immigration (only forced -for various reasons).

Just speculating at this point, so...later!
I like your ideas (on both threads) and agree with much (except some definite conclusions), but I think there are more external influences, as well as genetic plasticity and options, than we yet realize.

~~SA

Samwik. Sorry about lack of reply on other thread. I've been busy this weekend. In a hurry now too. We have 40,000 genes, Sam, not 40. Possibly more. Technically Y-chromosome and mtDNA are not genes but they act like them in many ways. I agree:

"a 0.1% adaptive advantage can spread to 95% of the population after about 100 generations; and a 0.5% advantage takes only 20 generations to spread like that."

I suspect there was quite a bit of migration as humans in different regions developed new ways to exploit the environment. It's accepted Y-chromosome and mtDNA distribution reflects this. Your other question concerns ecological speciation and I'll deal with it on the other thread. Thanks for your questions. It forces me to think about my own ideas. Hybrid vigour?

I have stuffed up again. It's on this thread. Regarding your sticklebacks. You're talking about ecological speciation here. But the gene for robustness and species separation doesn't spring up over night. If it did the individual with it would have no-one to breed with. I'd assume you're familiar with a bell curve. Characteristics in any species usually have a bell curve distribution. Extremes are picked off by selection so extremes are unusual in a populatiion. But if selection starts near the middle of the curve the population divides into two. The mobile separation between ground finches on Daphne Island in the galapagos is a geood example. More later hopefully.

Hiya Terry,
I'm just constantly amazed at how complex genetics can get. That's a new concept to me (splitting the curve in the middle).
Anyway, I enjoy reading and thinking about genetics and genomics, but I did't like this sentence, "But the gene for robustness and species separation doesn't spring up over night."
It's too limiting. Many of these genes already exist, or are co-opted and modified from elsewhere in the chromosomes, or are regulated differently or at different times, etc. There are even bimodal states for some genes (depending on environment).
Well, that's my understanding of things in general; but I'm no expert in this area.
Here's an example of the kind of things I'm talking about. Maybe I'm reading too much....

"It has been suggested that insertions and deletions (indels) have contributed to the sequence divergence between the human and chimpanzee genomes more than do nucleotide changes (3% vs. 1.2%).... Functional analysis reveals that the genes whose coding exons have been affected by human-specific indels are enriched in transcription and translation regulatory activities but are underrepresented in catalytic and transporter activities, cellular and physiological processes, and extracellular region/matrix. This functional bias suggests that human-specific indels might have contributed to human unique traits by causing changes at the RNA and protein level."
Genome Res. 17:16-22, 2007

and

"Novel retrotransposon analysis reveals multiple mobility pathways dictated by hosts....
Autonomous non-long-terminal-repeat retrotransposons (NLRs) proliferate by retrotransposition....
Our results suggest that several pathways exist for NLR retrotransposition and argue in favor of host protein involvement.
...indicating that the choice of the 5' joining pathway is affected by the host."
Genome Res. 17:33-41, 2007

and

"We mapped and sequenced the centromeric WFDC sublocus in 12 primate species that collectively represent four different mating systems. Our analyses reveal a 130-kb region with a notably complex evolutionary history that has included nested duplications, deletions, and significant interspecies divergence of both coding and noncoding sequences; together, this has led to striking differences of this region among primates and between primates and rodents...."
Genome Res. 17:276-286, 2007

and especially,

"Whereas many of the known regulatory codes reside in nontranslated regions of the genome, the present findings suggest that protein-coding regions can readily carry abundant additional information."
Genome Res. 17:405-412, 2007

and even [There's gotta be a great joke about the Scottish National Party out there somewhere.]

"Although many studies have been conducted to identify single nucleotide polymorphisms (SNPs) in humans, few studies have been conducted to identify alternative forms of natural genetic variation, such as insertion and deletion (INDEL) polymorphisms. In this report, we describe an initial map of human INDEL variation that contains 415,436 unique INDEL polymorphisms. These INDELs were identified with a computational approach using DNA re-sequencing traces that originally were generated for SNP discovery projects. They range from 1 bp to 9989 bp in length and are split almost equally between insertions and deletions, relative to the chimpanzee genome sequence. Five major classes of INDELs were identified, including (1) insertions and deletions of single-base pairs, (2) monomeric base pair expansions, (3) multi-base pair expansions of 2-15 bp repeat units, (4) transposon insertions, and (5) INDELs containing random DNA sequences. Our INDELs are distributed throughout the human genome with an average density of one INDEL per 7.2 kb of DNA. Variation hotspots were identified with up to 48-fold regional increases in INDEL and/or SNP variation compared with the chromosomal averages for the same chromosomes. Over 148,000 INDELs (35.7%) were identified within known genes, and 5542 of these INDELs were located in the promoters and exons of genes, where gene function would be expected to be influenced the greatest...."
Genome Res. 16:1182-1190, 2006

I know I saw something on dual function for single genes, but...maybe later.

~~SA

Samwik. Why didn't you like my comment:

"But the gene for robustness and species separation doesn't spring up over night."

The mutation probably sprang up overnight but the gene almost certainly wouldn't have. I agree mutations occur in many forms and have complicated results but that's not the point. Anyway at last I have a chance to respond to your question as to how the bell curve for a characteristic of a population can move rapidly to the right or left. What I meant by my statement was that this shift doesn't usually result from just a small subset of the population expanding and replacing the rest. As I've said before (and been criticised for it), this last idea is a hangover from victorian economic ideas of "survival of the fittest" and biblical ideas of a "chosen" population.

The closest we get to that situation is if a mutaion gives rise to a dominant gene. The resulting characteristic would then spread through the population as individuals with the mutation, and characteristic, leave more descendants who in turn leave more descendants etc.

But there is a much more likely way new characteristics spread through populations even more rapidly. We know from the study of dairy cattle that most mutations give rise to recessive genes. This is just as well or most of us wouldn't have survived our mother's pregnancy. Half the offspring of an individual with a recessive gene will also carry that gene. But selection cannot act on a single recessive gene. It can only act on double recessives. One quarter of the offspring of two individuals with a single recessive will have the new characteristic. I presume you know why. Double recessives happen through inbreeding. Half the offspring of one double recessive and one single recessive parent will have the characteristic. By that time single recessives could be widely and randomly distributed through the population.

Selection for the characteristic can then get seriously underway. This would lead to a rapid expansion of the characteristic. But it's the gene that spreads through the population, not just the element of the population with the characteristic. Other genes in the local population survive. In fact it has been pointed out each gene has a separate ancestor and has its own evolutionary history. A friend calls this the wave theory of evolution.

The same thing happens with Y-chromosome and mitochondrial DNA lines. They have simply moved through the human species over the generations, but they behave like dominant genes. For example many Y-chromosome lines have been spread by male population movements such as the Mongols. No-one suggests the Mongols sustained their Y-chromosome lines by taking women with them. This is the reason why the human Y-chromosome line is much younger than the mtDNA line. Likewise the mtDNA line distribution probably doesn't indicate an associated, now extinct, ancient male line. Besides, Y-chromosome Adam and mtEve's children would have had only half of their nuclear DNA, their grandchildren quarter of it and so on. The expansion of those lines is unlikely to be because of genetic advantage. Cultural advantage, probably yes.

Hope this all makes sense. The fluid speciation of Galapagos finches was covered on another thread.

I won't say that this is exciting stuff because I got yelled at when I did once before, so I'll just say that I was really pleased to see that this research probably gives some substance to the implications of the discovery of Mungo Man. The dating of these finds caused a lot of discussion, most experts saying that there were no humans in Australia 40.000 years ago! So these arguments must now be dead. The presence of the dingo amongst the aborigines was always stated as a reason for supposing that, since the dingo lived with the aborigines the animal would have migrated here with the people when they came here-- 5-10 thousand years ago!! The dingo had, I thought, been genetically linked to the Indian wild, or pi dog, and consequently it was supposed that the Aborigines came to Australia, with dogs, only comparatively recently. It was also supposed that the Aborigines were themselves descended from the original human inhabitants of India.

I actually taught this stuff as part of Australian History!!! I am rather pleased to see it blown out of the water and the long historical occupation of this country by its original inhabitants recognised.

PS I'm very puzzled by the Homo Erectus mention though. Was H E ever present in Australia?

Ellis wrote:

"Was H E ever present in Australia?"

No. The comment diminishes the authority of the article. By the way, where did you get yelled at?

Samwik wrote:

"That's a new concept to me (splitting the curve in the middle)".

Consider it my contribution to evolutionary biology. Well, it sort of comes from my brother and discussions of dairy cow genetics. Bell curves are commonly used to demonstrate various characteristics. When you combine dairy and beef cattle's characteristics you get a sort of double bell curve.

I got excited by the prospect of the galaxy and the planets making music, a lovely idea and one present in ancient and older literature as "the music of the spheres". I was apparently a bit over-happy about it and samwik (I think it was) accused me of being a gushing woman. So I have been trying to be objective and much more hairy chested ever since.... with noticeable lack of success. I still think scientists have the right to be excited sometimes too!

Ellis: "I still think scientists have the right to be excited sometimes too!"
Of, course. Have you seen a group of scientists witnessing the successful implementation of a space mission? I always recall the scene when Hubble transmitted its first images. Scientists do behave like other human beings for the simple reason that they are like other people - and some can become exceedingly irate when anyone implies that they are different. There was a BBC program called 'Hard Talk'. It was the task of the host to conduct a tough and often rather insensitive interview with his guests. He usually seemed to have the upper hand. One exception was with Richard Dawkins, and another with a the winner of the ?2000 winner of the Nobel Prize for physics. I don't recall his name. The host asked him a question that implied that a scientist is in some way not an 'ordinary' human being. The resulting scene was such that I was surprised it wasn't taken off the air. "Well done, sir", I thought.

I have found all the above contributions, most interesting.

Far be it for me to dispute the facts that 'Man Came out of Africa.'
Or even 'Came out of Africa' and found his way to Australia. But there are relatively big genetic distances between Australian Aboriginese, and Sub-Saharan Africans, since the Indian Ocean is in the way. Nor are Aborigines closely related to Europeans, since Asia stands in the way.

My remarks may sound trite, but Aborigines could have come from New Guinea by land bridge or even rafts. Obviously very few came, and were left in isolation.
Nor would I like to say that there was no contact at all, since it is known that prehistoric Southeast Asians rode rafts 4,000 miles across the Indian Ocean to colonize Madagascar.

But I would like to leave Australia, and rather concentrate upon Eastern Asia, and China, and wonder how it could be possible for the "Out of Africa" theory to become reconciled within the time scale of 50k years Out of Africa?

I just cannot believe that within that short time scale, mankind moved from Africa to colonise China?
China has a very ancient history. With some even ancient fossils of early man, at least as old, and in some cases even older that those hominids found in Kenya, Spain, and elsewhere.

I have tried to come up with a Fossil list, thats not in any particular age order, to show that there has not been enough time allowed for mankind to colonise the far East, from Africa.

Australopithecus afarensis
The most famous member of this species is Lucy, an adult female skeleton discovered in 1974 and nicknamed after a Beatles song. Lucy lived about 3.18 million years ago and was fully capable of walking and running on two legs.

Australopithecus africanus
An early descendent of Lucy and lived in Southern Africa between 2 - 3 million years ago. Its brain was larger than Lucy's and its facial features were more human-like.

Paranthropus aethiopicus
An early ape-like hominid, that walked on two legs and lived between 2.8 - 2.2 million years ago. Based on skull measurements, scientists concluded this species had the smallest adult hominid brain ever discovered.

Paranthropus bosei
They split from the line leading to modern human some 2 million years ago and lived alongside our ancestors for millions of years, but seemed to have died out.

Homo habilis
The missing link between the ape-like hominids like Lucy and the more human-like ones that came after? It had long ape-like arms but walked on two feet and was capable of creating crude tools.

Homo ergaster
Scientists can't decide whether this African hominid is just a failed predecessor of H. erectus or the rightful ancestor of modern humans. It had a thinner skull than H. erectus, but was more proficient at making tools and using fire.

Homo erectus
H. erectus is generally believed to be the direct ancestor of modern humans and also the first hominid to live in caves and tame fire.

Homo floresiensis
I included this species, since they are diminutive, which could be construed that they are new species of hominid, discovered on the Indonesian island, and therefore unlikely to have "Come out of Africa', so dimunitive?

Cro-Magnon man
They looked fairly identical to modern humans, and lived in Europe between 35,000 and 10,000 years ago. Their cave paintings and sculptures are the earliest known examples of art by a prehistoric people.

Neanderthal man
Stocky and squat. Neanderthals looked distinctly different from modern humans. But they buried their dead, cared for their sick and injured, and may have been capable of language and music. Scientists recently put together a complete Neanderthal skeleton and are working on the genome.

Peking Man China. -Asia
Lived 200k-500k years ago in caves at Zhoukoudian. The bones of Peking Man discovered in the cave in the hill's north face include six complete or relatively complete skulls, eight skull
fragments, six pieces of facial bone, 15 mandibles, 153 teeth, seven sections of broken femur, one broken shinbone, three pieces of upper arm bone, one clavicle and one wrist bone belonging to more than 40 individuals of different ages and sexes.

Pithecanthropus VIII, Homo erectus -Asia
Discovered by Sastrohamidjojo Sartono in 1969 at Sangiran on Java. This consists of a fairly complete cranium, with a brain size of about 1000 cc. It is the most complete erectus fossil from Java. This skull is very robust, with a slightly projecting face and huge flaring cheekbones. It has been thought to be about 800,000 years old.

The Maba cranium dated to approximately 120,000 years ago was discovered in 1958 in the southern Chinese province of Guangdong. It was the first substantial specimen of a pre-modern form of H. sapiens found in East Asia. It was iniatially thought to be an Asian Neandertal but does not in fact show any of the derived features of Neandertals as known from Europe and the Near East. The Maba skull is similar to other more complete finds of pre-modern H. sapiens subsequantly found in China,
differing only in minor ways, such as the size and shape of the eye orbits and nasal bones. It is similar to the recently discovered 'Narmada' skull from India.

The Liujiang cranium is similar to recently discovered southern Chinese crania dated to the end of the Pleistocene, approximately 10,000 years ago. Cultural remians from the nearby Bailiandong cave site have been dated to approximately 30,000 years before present. It is therefore likely that the Liujiang remains date to the end of the Late Pleistocene, approximately 10-30,000 years ago.

Sorry about the long list, but I am trying to show in my own way that the origin of modern Asian peoples are still a source of controversy in the human Evolution story. Mankind has lived in Asian a very long time. Some of the oldest known fossils of prehistoric man have been found on the island of Java in Indonesia and near Peking in northern China.

The world's oldest civilizations are Asian. Chinese civilization is nearly 5,000 years old, and the civilization of India is nearly that old.

After looking at my very incomplete list, I am certain that these archaic Asians evolved as a separate and distinct line, alongside the 'Out of African' hominids.

I feel Asians have too many facial, and body-type differences, to have arisen from the same stock?

Furthermore under the Scienceagogo topic entitled "Ancient Cavemans Virus Resurrected" (dated 08-05-2007 below) it seems pretty certain that once a heritable virus attacks ancient humans, -or even modern humans? It can become trapped in the human DNA for all time.
Analogy is - a disease,...that confers resistance to to its host only after attacking it.

Viruses typically infect whole populations, or substantial parts of them, so two members of a breeding pair are very likely to carry the same new instructions. This "ancient cavemans virus" theory, is a possible new way for evolution to advance, very quickly? Pandemic flue, Blackdeath, now dormant, due to large population resistance.

In fact, genes for recessive diseases are are very easy to find -unlike other genes. For instance Tay-Sachs, or Sickle cell, certain form of blindness, different eye colorings, breast cancers, heamophilia, and many more, are easy to trace within families.

Notice, that some of these diseases are non-existant within the Asian population?
Admittedly, I have not researched this line, but I have no reason to believe it is untrue in the main.

The above, does seem to show the possibility that Asians evolved from a separate stock. Since all,...or some some of these recessive genetic diseases, could be carried by a heritable viral genome, which would be noticable within the present Asian population?

I should have included Blood types as a difference as well. Not just the four groups but their 14 sub-divisions as well.

Of course this idea could work back the other way as well. I'm thinking from ancient Asia, back to Aborigine Australia. Since thats the way human movement went.
Do Aborigines have any form of ancient heritable DNA/resistance to Yellow Fever, Chandipura virus, or other ancient Asian virus?
Research will tell.

Ellis,
You are talking about an actor in a movie, whom I described; my opinion was not about "Ellis."
Y'know, in trying to find the post you are referring to, I ran across 3-4 other instances where I complimented your previous post and sometimes wrote about what you had said, building on your comment in a favorable manner. The left side of my chest is hairy, but the right side is completely hairless (just some genetic oddity, I guess); but please cease and desist, the image of me that you are incorporating into your personal story [narrative] is not accurate....

~Sam

p.s. It was about global warming, not music as you say above.

You overstate; I don't think that "review" could be called "yelling."

But about your last post (see #21586):

Darn! Please don't perpetuate such innaccurate attributions to me! I would never use language like that!

You are referring to:
"I certainly agree that the sun is a very big player. I did not appreciate the woman who chirpily told us what “exciting news” it was that even our galaxy influences our climate (ala Mike Kremer's post on the Physics forum).

Well, those where some thought's on the film. Overall the soothing gentle tones of the AGW's and the strident shoutings of the PGW's (anti/proGW) gave it the look of a slick propoganda film, similar in style to Incovenient Truth (IT)." -samwik (post #21044)

to which you responded:
Samwik--Since I was probably the "woman" who expressed excitement at the thought of the celestial influences reaching this insignificant planet...."

Hey, I was reviewing (first attempt) "Al Gore's global warming film." I certainly didn't know that "Ellis" was that person I commented about. Please also note the "audio perspective" in the actual review (post #21044)

Although I made the effort to quote the lady in the film correctly, you, Ellis, did not quote me correctly in your response.
And you have NOW attributed to me that horrible phrase, "samwik (I think it was) accused me of being a gushing woman." -Ellis

I guess there's wisdom in the advice to not read your own reviews.
How does "the woman who chirpily told us..." -samwik
translate into "being a gushing woman?" -Ellis

please see the full response at:
http://www.scienceagogo.com/forum/ubbthreads.php?ubb=showflat&Number=21086#Post21086

So you, Ellis, were really the woman in the film?

Other than that, how was the play Mrs. Lincoln?

*_*

Mike, cool post. Will check out later.

~SA

I'm new to this topic, and have only the sketchiest ideas about it, so it's very much question (and assumption) time for me!

Mike: "I have tried to come up with a Fossil list, that’s not in any particular age order, to show that there has not been enough time allowed for mankind to colonise the far East, from Africa." and "I feel Asians have too many facial, and body-type differences, to have arisen from the same stock?"

Somewhere along the line, according to the genetics, all races of modern humans must have had a common ancestor. Correct?
That common ancestor was the 'same stock', of which you speak, from which we derive the shared genetic relationships. Correct?
The physical differences between extant races suggest a prolonged period of mutually isolated (or nearly isolated) evolutionary development. Correct?

My questions is:

How long ago did the common ancestor live, i.e., is "Out of Africa" correct, or not"?

I found some interesting answers in "Human Evolution at the Smithsonian Institution..."

http://www.mnh.si.edu/anthro/humanorigins/ha/sap.htm

...including these two hypotheses:

(1) Multiregional Hypothesis.
"The origin of modern Homo sapiens is not yet resolved. Two extreme scenarios have been proposed. According to the first, the distribution of anatomical traits in modern human populations in different regions was inherited from local populations of Homo erectus and intermediate "archaic" forms. This "Multiregional Hypothesis" states that all modern humans evolved in parallel from earlier populations in Africa, Europe and Asia, with some genetic intermixing among these regions. Support for this comes from the similarity of certain minor anatomical structures in modern human populations and preceding populations of Homo erectus in the same regions.

(2) Out of Africa Hypothesis.
"A different model proposes that a small, relatively isolated population of early humans evolved into modern Homo sapiens, and that this population succeeded in spreading across Africa, Europe, and Asia -- displacing and eventually replacing all other early human populations as they spread. In this scenario the variation among modern populations is a recent phenomenon. Part of the evidence to support this theory comes from molecular biology, especially studies of the diversity and mutation rate of nuclear DNA and mitochondrial DNA in living human cells.From these studies an approximate time of divergence from the common ancestor of all modern human populations can be calculated. This research has typically yielded dates around 200,000 years ago, too young for the "Multiregional Hypothesis." Molecular methods have also tended to point to an African origin for all modern humans, implying that the ancestral population of all living people migrated from Africa to other parts of the world -- thus the name of this interpretation: the "Out of Africa Hypothesis."

Mike, you suggest that (1) "Multiregional Hypothesis" seems likely but, from the above info, (2) looks more convincing.

Sorry samwik- What a comedy of errors. I apologise for having misjudged you, and I certainly don't expect to always have positive feedback. One good thing though, everyone seems to agree that scientists should be excited by their discoveries and in a time when young people are deserting science (at least in this country) for more instantly rewarding studies perhaps expressing that excitement more freely would inspire them in the future.

Re Homo Erectus.
There seems to be no serious suggestion that this species ever existed in Australia, so this absence would argue for the Out of Africa theory. There really does seem to be a problem with Mungo Man and the date of at least 40,000 years attached to his discovery. So is H.E necessarily the only possible source for the development of modern humans? Could the Aborigine have evolved from a different source and/or then moved here?

Mungo's bones have really mucked up a neat hypothesis.

This is a confusing topic. For example:

http://donsmaps.com/mungo.html

"The comprehensive study of 25 different sediment layers at Mungo - a collaboration between four universities, the CSIRO, and NSW National Parks and Wildlife and led by Bowler - concludes that both graves are 40,000 years old. This is much younger than the 62,000 years Mungo Man was attributed with in 1999 by a team led by Professor Alan Thorne, of the Australian National University."

"Now, however, Thorne says the age of Mungo Man is irrelevant to this origins debate. Recent fossils finds show modern humans were in China 110,000 years ago. "So he has got a long time to turn up in Australia. It doesn't matter if he is 40,000 or 60,000 years old." "

Compare that with:

http://www.eurekalert.org/pub_releases/2007-04/wuis-cem040207.php

"The skeleton [in China] dates to 42,000 to 38,500 years ago, making it the oldest securely dated modern human skeleton in China and one of the oldest modern human fossils in eastern Eurasia."

Also, looking through the websites, I find conflicting affirmations of the time of the migration out of Africa. Some, like the one Mike quoted (which appears in Science Daily), say 55,000 to 65,000 years ago, while others say 70,000 and one (above) says that modern humans were already in China 110,000 years ago!