Tag Archives: Out of Africa theory

Detecting ancient admixture and estimating demographic parameters in multiple human populations

Detecting ancient admixture and estimating demographic parameters in multiple human populations (pdf)

A rather odd looking pdf- runs a lot like a mini PowerPoint presentation, by the man who published the recent paper that concluded there probably was archaic admixture in humans. And yet again.. I see the 40k-60k OOA date in print. Grr.

Detecting ancient admixture and estimating demographic parameters in multiple human populations

We analyze patterns of genetic variation in extant human polymorphism data from the NIEHS SNPs project to estimate human demographic parameters. We update our previous work by considering a larger data set (more genes and more populations), and by explicitly estimating the amount of putative admixture between modern humans and archaic human groups (e.g., Neandertals, Homo erectus, H. floresiensis). We find evidence for this ancient admixture in European, East Asian and West African samples, suggesting that admixture between diverged hominin groups may be a general feature of recent human evolution.

Yet another DNA study that finds evidence of archaic contributions in modern human groups. Odd how these don’t make the news but anything that finds in favour of the OOA gets splattered all over the media.

We estimate admixture proportions of 14 % (95% CI: 8 – 20 %) in the European-American sample and 1.5% (95% CI: 0.5 – 2.5 %) in the East Asian sample. In both cases, the relative log-likelihood for a = 0 (i.e., no ancient admixture) is significantly lower than the maximum likelihood (likelihood-ratio test, p < 10-3) , which provides additional evidence (along with the S* results in the previous paragraph) that ancient admixture occurred. The estimates of admixture rates in Europeans are consistent with estimates of Neandertal admixture obtained from analyses of Neandertal DNA (Serre et al. 2004; Noonan et al. 2006), [. . .] Unlike previous studies, we incorporated admixture between archaic and modern humans as an additional demographic parameter to be co-estimated. Interestingly, we could exclude no admixture (i.e., exclude a = 0) in both of the non-African populations studied

 The observation that all (three) populations studied seem to have evidence for ancient admixture suggests that ancient population structure may be a common feature of all contemporary human populations, and this ancient structure may predate the initial expansion of modern humans out of Africa.

Although some of the archaic DNA isn’t found in Africa, which would make the archaic admixture prior to the OOA hard to explain. This paper also finds evidence for archaic admixture in the Yoruba. I remember reading previously that the X chromosome showed signs of archaic ancestry in one pygmy group, so archaic ancestry in West Africa is supported by another paper. More detail… Testing for Archaic Hominin Admixture on the X Chromosome, which concluded the TMRCA was about 2 million years for one locus on the X chromosome and concludes..

For now, this locus represents a genealogical history that is most consistent with recent admixture from an archaic hominin population in Asia

Which is a far cry from Svante Paabo’s ‘no admixture but they were within the range of modern humans’ claim, which I found a bit odd. So you found they had essentially human DNA with us but decided they didn’t mingle …how?

I’d just like to comment that the OOA/RAR theory leaves absolutely NO room for any ancient DNA cropping in non Africans that doesn’t have a root in Africa- but it does, with remarkable frequency. In other words, the OOA doesn’t ‘fit’. That OOA is true of mostof our ancestry means sod all, it has to be true for all of it and it’s rather blatantly NOT the case, as there are a plethora of non-African but ancient in Eurasia mutations that invalidate it. Particularly the non African MC1R mutation ages that have ages of 100k-250k and a TMRCA of a million years.

Both African and non-African data suggest that the time to the most recent common ancestor is ª1 million years and that the age of the global 314 variant is 650,000 years. On this time scale, ages for the Eurasian distributed Val60Leu, Val92Met, and Arg163Gln variants are 250,000–100,000 years;

I’m going to have to make up a proper list of the DNA studies that find against the OOA theory.

As well as ‘Out of Africa’ there was a ‘Deeper into Africa ‘

Bayesian coalescent inference of major human mitochondrial DNA haplogroup expansions in Africa.

Atkinson QD, Gray RD, Drummond AJ.

Past population size can be estimated from modern genetic diversity using coalescent theory. Estimates of ancestral human population dynamics in sub-Saharan Africa can tell us about the timing and nature of our first steps towards colonizing the globe. Here, we combine Bayesian coalescent inference with a dataset of 224 complete human mitochondrial DNA (mtDNA) sequences to estimate effective population size through time for each of the four major African mtDNA haplogroups (L0-L3). We find evidence of three distinct demographic histories underlying the four haplogroups. Haplogroups L0 and L1 both show slow, steady exponential growth from 156 to 213kyr ago. By contrast, haplogroups L2 and L3 show evidence of substantial growth beginning 12-20 and 61-86kyr ago, respectively. These later expansions may be associated with contemporaneous environmental and/or cultural changes. The timing of the L3 expansion-8-12kyr prior to the emergence of the first non-African mtDNA lineages-together with high L3 diversity in eastern Africa, strongly supports the proposal that the human exodus from Africa and subsequent colonization of the globe was prefaced by a major expansion within Africa, perhaps driven by some form of cultural innovation.

That the East African population expanded into Africa as well as Eurasia explains how the ancient Eurasian-like Hofmeyr skull got into South Africa. Finally, something helping to clear that mystery up.

A Libyan ‘Out of Africa’ route for ancient humans.

Is suggested in this recent article, kindly pointed out by Mr Mathilda a couple of days ago. Finally, I manage to pry my kids off the damn computer to post it.

The widely held belief that the Nile valley was the most likely route out of sub-Saharan Africa for early modern humans 120,000 year ago is challenged in a paper published this week in the Proceedings of the National Academy of Sciences. A team led by the University of Bristol shows that wetter conditions reached a lot further north than previously thought, providing a wet ‘corridor’ through Libya for early human migrations. The results also help explain inconsistencies between archaeological finds.

While it is widely accepted that modern humans originated in sub-Saharan Africa 150-200 thousand years ago, their route of dispersal across the hyper-arid Sahara remains controversial. The Sahara covers most of North Africa and to cross it on foot would be a serious undertaking, even today with the most advanced equipment.

Well-documented evidence shows there was increased rainfall across the southern part of the Sahara during the last interglacial period (130-170 thousand years ago). The Bristol University team, with collaborators from the universities of Southampton, Oxford, Hull and Tripoli (Libya), investigated whether these wetter conditions had reached a lot further north than previously thought.

Anne Osborne, lead author on the paper said: “Space-born radar images showed fossil river channels crossing the Sahara in Libya, flowing north from the central Saharan watershed all the way to the Mediterranean. Using geochemical analyses, we demonstrate that these channels were active during the last interglacial period. This provides an important water course across this otherwise arid region.” The critical ‘central Saharan watershed’ is a range of volcanic mountains formerly considered to be the limit of this wetter region.

The researchers measured the isotopic composition of snail shells taken from two sites in the fossil river channels and from the shells of planktonic microfossils in the Mediterranean. Despite being hundreds of kilometres from the volcanic rocks in the mountains of the Saharan watershed, these shells had a distinctly volcanic ‘signature’, very different from the other rocks surrounding the sites. Water flowing from these volcanic mountains is the only possible source of this signature.

Dr Derek Vance, senior author on the paper, added: “The study shows, for the first time, that monsoon rains fed rivers that extended from the Saharan watershed, across the northern Sahara, to the Mediterranean Sea. These corridors rivalled the Nile Valley as potential routes for early modern human migrations to the Mediterranean shores.”

The similarities between Middle Stone Age artefacts in places like Chad and the Sudan, with those of Libya, strongly support this theory. “We now need to focus archaeological fieldwork around the large drainage channels and palaeo-lakes to test these ideas” said Nick Barton, a contributor to the project from the University of Oxford.

Link

The widely held belief that it was the Nile? Generally I see the Gate of Tears pushed as the exit point, whenever I bang on about the Nile being the most likely exit route everyone ignores me. What really interested me is the 120,000 date. Very interesting. I think the 120k date is quite possible. I think the dates from the mt DNA and Y DNA don’t show any signs of accuracy. When I compared a couple they didn’t match the population expansions I knew of at all (in North Africa).

I’d like to point out that the Nile flows through the Sudan, then up into North Africa. Personally I think this theory is a bit weak, I’m still going with the Nile. I support 120k as a reasonable exit date, there was never any good evidence modern humans became extinct in the Levant when it’s climate changed.

A serial founder effect model for human settlement out of Africa

A serial founder effect model for human settlement out of Africa

Omkar Deshpande, Serafim Batzoglou, Marcus W. Feldman, L. Luca Cavalli-Sforza

Abstract

The increasing abundance of human genetic data has shown that the geographical patterns of worldwide genetic diversity are best explained by human expansion out of Africa. This expansion is modelled well by prolonged migration from a single origin in Africa with multiple subsequent serial founding events. We discuss a new simulation model for the serial founder effect out of Africa and compare it with results from previous studies. Unlike previous models, we distinguish colonization events from the continued exchange of people between occupied territories as a result of mating. We conduct a search through parameter space to estimate the range of parameter values that best explain key statistics from published data on worldwide variation in microsatellites. The range of parameters we use is chosen to be compatible with an out-of-Africa migration at 50–60Kyr ago and archaeo–ethno–demographic information. In addition to a colonization rate of 0.09–0.18, for an acceptable fit to the published microsatellite data, incorporation into existing models of exchange between neighbouring populations is essential, but at a very low rate. A linear decay of genetic diversity with geographical distance from the origin of expansion could apply to any species, especially if it moved recently into new geographical niches.

I noticed this when nosing through Dienekes blog (once a week on average). This pretty much supports my ‘weak eden’ stance, although I’d certainly say huh? over the OOA date as being way to recent (Australoids were entering Oz and South America about 50k ago, and the Liujiang skull is at least 68k old). I’m not sure what kind of difference an older exit date would make to their study though. If I ever find the entirety of this paper I’ll post it.

The Liujiang skull.

So this is the skull that’s causing all the fuss, the Liujiang skull. it was found in Tongtianyan in the Guangxi Zhuang Autonomous Region (South Easternmost China) in 1958 by people collecting fertilizer.

There’s a bit of uncertainty over its age; a uranium series gave a date of 67,000 years +/-5,000; but the flora and fauna in the cave seem to indicate an older date. There are also some modern human teeth found in the same area with a very old date of 94,000 BP. So really the only date you could give it is ‘inconveniently old for the recently out of Africa theory’.

The skulls don’t really bear more than a passing resemblance to modern mongoloid Asians, there being some significant differences in the teeth at least. The eye orbits are more rectangular as well. This also agrees with other data showing that modern mongoloids area a rather recent arrival in Asia, who have become massively successful in a very short space of time- the oldest Mongoloid shaped skull in Asia being about 7,000 years old.

  

 

U-Series dating of Liujiang hominid site in Guangxi, Southern China

21 July 2002;  accepted 9 September 2002.

It has been established that modern humans were living in the Levant and Africa ca. 100 ka ago. Hitherto, this has contrasted with the situation in China where no unequivocal specimens of this species have been securely dated to more than 30 ka. Here we present the results of stratigraphic studies and U-series dating of the Tongtianyan Cave, the discovery site of the Liujiang hominid, which represents one of the few well-preserved fossils of modern Homo sapiens in China. The human fossils are inferred to come from either a refilling breccia or a primarily deposited gravel-bearing sandy clay layer. In the former case, which is better supported, the fossils would date to at least 68 ka, but more likely to 111–139 ka. Alternatively, they would be older than 153 ka. Both scenarios would make the Liujiang hominid one of the earliest modern humans in East Asia, possibly contemporaneous with the earliest known representatives from the Levant and Africa. Parallel studies on other Chinese localities have provided supporting evidence for the redating of Liujiang, which may have important implications for the origin of modern humans.

Ancient DNA in Asians casts doubt on the ‘Out of Africa’ theory.

Evidence for Archaic Asian Ancestry on the Human X Chromosome
Daniel Garrigan1, Zahra Mobasher1, Tesa Severson1, Jason A. Wilder1
and Michael F. Hammer1,2 October 13, 2004

Abstract
The human RRM2P4 pseudogene has a pattern of nucleotide polymorphism that is unlike any locus published to date. A gene tree constructed from a 2.4 kb fragment of the RRM2P4 locus sequenced in a sample of 41 worldwide humans clearly roots in East Asia and has a most recent common ancestor ~2 million years before the present. The presence of this basal lineage exclusively in Asia results in higher nucleotide diversity among non-Africans than Africans. A global survey of a single nucleotide polymorphism that is diagnostic for the basal, Asian lineage in 570 individuals shows that it occurs at frequencies up to 53% in south China, while only one of 177 surveyed Africans carries this archaic lineage. We suggest that this ancient lineage is a remnant of introgressive hybridization between expanding anatomically modern humans emerging from Africa and archaic populations in Eurasia.

Recently Hammer et al. (2004) analyzed global human nucleotide variation at 15 X linked loci, one of which stands out as unique in its pattern of polymorphism. In a global sample of 41 individuals, sequence variation at the ribonucleotide reductase M2 subunit pseudogene 4 (RRM2P4) is partitioned into two divergent, basal lineages. Both of these lineages are found in Asia, while only one is found in sub-Saharan Africa (figure 1B). The two lineages differ by five fixed mutations, leading to an estimate for the time to a most recent common ancestor (TMRCA) that is ~2 million years before the present.

There are quite a few estimated dates for genes that really cast a shadow over the OOA theory, one red hair mutation in Europeans had a date of 80,000 years, which would stick it into a Neanderthal time frame. Any one curious, look up the ‘out of Africa deception’ for a list of them.

The 60,000 year old exit from Africa…that makes no sense at all.

It’s claimed to be about 60,000 years ago from the Horn of Africa..

Let me just say I’m with Stephen Oppenheimer on this one. That ‘60,000 years ago’ exit date is pretty impossible, for several reasons…

  • The age of the haplotype M mutation, occuring in the Pakistan? area is dated to 64,000 years ago at least.
  • There’s a modern human skull in Luijiang China 68,000 years old (at least) and quite likely older.
  • There’s evidence of modern humans under the mount Toba explosion 74,000 years old in the Malay peninsula
  • There’s evidence of modern humans on top of the Toba Ash, suggesting the population didn’t die out in East Asia
  • The age of Y chromosome Adam in Africa is estimated to be 60,000 BP 4,000 years after the date of the M mtDNA mutation in South Asia. There were also people in Far East Asia by then. They must have some men not descended from Y chromsome Adam to keep going, but they are not present now.  If that isn’t proof of selection in Y chromosmes I don’t know what is.

A good look at the Mt DNA of Pakistan and India shows some L haplotypes present in Asia, so it seems a good amount of lead time can be added to the 64,000 years date, as haplotype L ‘s seems to have got there a while before. Also, In an age that great for the estimated date of a MtDNA haplotype, even a minor percentage error can add up to ten thousand years and more.

After reading some of his articles, it seems Oppenheimer is behind the colonisation of Australia at the low tide date of 65,000 years. He then worked out that you’d need at least 10,000 years to reach there from Africa.

Add this 10,000 years to the 74,000 date (Toba date) and this gives you at least 85,000 years BP from the Gate of Tears (Red sea).

So essentially, you are looking at an exit date of at least 85,000 years and probably a lot older.

There’s also the issue of ‘was there really one exit ?’ To my knowledge the Nile has always flowed into the Mediterranean, making a permanent route to the Mahgreb. There does seem to be an early seperation of Mt DNA haplotype N and M, one swinging North into central Asia (from a Nile exit?) and the other following the coastal route into Australia.

This brings me to the issue of modern humans in North Africa, in Jebel Irhoud, dated to 160,000 years years ago. If modern humans were in North africa then, how did they first exit sub Saharan Africa 100,000 years later? Another seeming impossiblity. There still seems to have been a human population there 82,000 years ago, they left bones and beads.

This all leads me to question the validity of ‘one recent exit by the Gate of Tears’ quite deeply. Thismistrust of it is made stronger by a couple of studies that have concluded mt DNA is subject to natural selection, and is not a neutral marker, so it’s entirely possible for less successful lineages to die out (there’s evidence climate affects what lineages thrive).

One DNA study I’ve seen based on other DNA markers dated the split from the East African population at 120,000 BP, and the European split from Asians at about 40,000 BP. This would roughly fit the presence of modern humans in Israel at Skhul, at 125,000 BP. It also matches roughly the date at which Europeans started moving into Neanderthal territory, so I’m inclined to support this, and assume that the MtDNA dates are very wrong, for the older clades at least.

Then there’s the issue of Mungo man, mt DNA from him showed he wasn’t descended from mitochondrial Eve.

It has to be remembered that the world wasn’t empty of people at this time. Asia was full of Homo Erectus, and from Europe into Siberia there were Neanderthals. This wasn’t just a case of expanding into an empty territory, they had two subspecies (or races, the jury is out on that one) to wipe out. This would add to the time it took to get from A to B.

This also raises the point ‘were we ever really genetically isolated from Neanderthals and Homo Erectus?’, as AMH’s seem to have been mooching around in North Africa nearly the whole time before we officially exited Africa. The fact that the Jebel Irhoud remains were initially misidentified as Neanderthal should be a clue to the answer

The out of Africa theory makes no sense at all. Beats me how it remains the accepted paradigm.

The 70,000 year ago ‘Out of Africa’ date, and why it’s not possible.

Is the reason the recently out of Africa theory is so popular, is that it’s compatible with the Bible?

If you think about it. As long as you don’t think that the times in Genesis are literal, as the word ‘yom’ can be read as ‘age’ not just ‘day’ in Hebrew. It has an Adam, and an Eve, moving out of an area that is commonly regarded as being Eden (Yemen/North East Africa). The latest possible date for the exodus (60K) is the one you usually see in the media, although it’s fast becoming obvious that this is laughably wrong, due to the find in Morocco and Luijang. I think the American press are pandering to the Christian masses.

The information that wildly differing X chromosomes are to be found in Asians and Europeans, but not in Africans is being quietly ignored. Why? Genetically, this is big news.

MILWAUKEE, WISCONSIN–About 1200 researchers gathered near the shores of Lake Michigan here from 5 to 9 April to discuss early Englishmen, the birth of modern humans, and Stone Age weapons.

In the past 15 years, a flood of genetic data has helped propel the Out of Africa theory into the leading explanation of modern human origins. DNA from mitochondria (mt DNA), the Y chromosome, and ancient humans each suggest that the ancestors of all living people arose in Africa some time after 200,000 years ago, swept out of their homeland, and replaced archaic humans around the globe without mixing with them. But at a genetics symposium, two independent groups presented data from the X chromosome hinting that modern humans interbred with other human species: The teams found possible traces of archaic hominids in our genes. “Just as the Y and mt DNA data seemed to have settled it, the new data revive the question [of interbreeding],” says Stanford University’s Joanna Mountain, co-organiser of the symposium. “The controversy is not settled.”

Geneticists Makoto Shimada and Jody Hey of Rutgers University in Piscataway, New Jersey, presented an intriguing haplotype–a set of genetic mutations inherited together–that appears to have ancient roots in Asia rather than Africa. Shimada sequenced a 10.1-kilobase non coding region in 659 individuals from around the world. Overall, the genetic variations were most frequent in Africa, just as expected if our ancestors were a subset of ancient Africans who migrated out of that continent. But one rare variant, appropriately named haplotype X, appeared in nine individuals from Europe to Oceania but was entirely absent in Africa. Shimada estimated that the haplotype arose 1 million years ago, long before the modern human exodus from Africa. “Haplotype X is difficult to explain by the recent African origins model,” says Shimada. “It’s very old, it’s rare, and it is widespread outside of Africa.”

In independent work, geneticist Michael Hammer of the University of Arizona in Tucson offered a similar example. Hammer and postdoc Dan Garrigan identified a 2-million-year-old haplotype in the RRM2P4 region of the X chromosome that is common in East Asia but vanishingly rare in Africa. Their work, published 2 months ago in Molecular Biology and Evolution, raises the possibility that the haplotype arose in very ancient Asian populations, presumably of Homo erectus, an ancient human once found across Asia. “This is what you’d expect if you had introgression” between modern humans and H. erectus, Hammer said.

I had to look for this research. I’m not saying it’s been suppressed, I’m just saying that no-one is making it easy to find. I think that a lot of people have built reputations on the ‘recent African origin’ theory, and it would be embarrassing to wave this kind of discovery around, especially if it’s unpalatable to religious people.

People at Pinnacle Point.

Again, ancient humans were more widespread.

ASUNews

October 17, 2007

ASU team detects earliest modern humans

Evidence of early humans living on the coast in South Africa 164,000 years ago, far earlier than previously documented, is being reported in the Oct. 18 issue of the journal Nature.

The international team of researchers reporting the findings include Curtis Marean, a paleoanthropologist with the Institute of Human Origins at Arizona State University and three graduate students in the School of Human Evolution and Social Change.

“Our findings show that at 164,000 years ago in coastal South Africa humans expanded their diet to include shellfish and other marine resources, perhaps as a response to harsh environmental conditions,” notes Marean, a professor in ASU’s School of Human Evolution and Social Change. “This is the earliest dated observation of this behavior.”

Further, the researchers report that co-occurring with this diet expansion is a very early use of pigment, likely for symbolic behavior, as well as the use of bladelet stone tool technology, previously dating to 70,000 years ago.

These new findings not only move back the timeline for the evolution of modern humans, they show that lifestyles focused on coastal habitats and resources may have been crucial to the evolution and survival of these early humans.

Searching for beginnings

After decades of debate, paleoanthropologists now agree the genetic and fossil evidence suggests that the modern human species – Homo sapiens – evolved in Africa between 100,000 and 200,000 years ago.

Yet, archaeological sites during that time period are rare in Africa. And, given the enormous expanse of the continent, where in Africa did this crucial step to modern humans occur?

“Archaeologists have had a hard time finding material residues of these earliest modern humans,” Marean says. “The world was in a glacial stage 125,000 to 195,000 years ago, and much of Africa was dry to mostly desert; in many areas food would have been difficult to acquire. The paleoenvironmental data indicate there are only five or six places in all of Africa where humans could have survived these harsh conditions.”

In seeking the “perfect site” to explore, Marean analysed ocean currents, climate data, geological formations and other data to pin down a location where he felt sure to find one of these progenitor populations: the Cape of South Africa at Pinnacle Point.

“It was important that we knew exactly where to look and what we were looking for,” says Marean. This type of research is expensive and funding is competitive. Marean and the team of scientists who set out to Pinnacle Point to search for this elusive population, did so with the help of a $2.5 million grant from the National Science Foundation’s Human Origins: Moving in New Directions (HOMINID) program.

Their findings are reported in the Nature paper “Early human use of marine resources and pigment in South Africa during the Middle Pleistocene.” In addition to Marean, authors on the paper include three graduate students in ASU’s School of Human Evolution and Social Change: Erin Thompson, Hope Williams and Jocelyn Bernatchez. Other authors are Miryam Bar-Matthews of the Geological Survey of Israel, Erich Fisher of the University of Florida, Paul Goldberg of Boston University, Andy I.R. Herries of the University of New South Wales (Australia), Zenobia Jacobs of the University of Wollongong (Australia), Antonieta Jerardino of the University of Cape Town (South Africa), Panagiotis Karkanas of Greece’s Ministry of Culture, Tom Minichillo of the University of Washington, Ian Watts from London and excavation co-director Peter J. Nilssen of the Iziko South African Museum.

The Middle Stone Age, dated between 35,000 and 300,000 years ago, is the technological stage when anatomically modern humans emerged in Africa, along with modern cognitive behavior, says Marean. When, however, within that stage modern human behavior arose is currently debated, he adds.

“This time is beyond the range of radiocarbon dating, yet the dates on the finds published here are more secure than is typical due to the use of two advanced and independent techniques,” Marean says.

Uranium series dates were attained by Bar-Matthews on speleothem (the material of stalagmites), and optically stimulated luminescence dates were developed by Jacobs. According to Marean, the latter technique dates the last time that individual grains of sand were exposed to light, and thousands of grains were measured.

Migrating along the coast

“Generally speaking, coastal areas were of no use to early humans – unless they knew how to use the sea as a food source” says Marean. “For millions of years, our earliest hunter-gatherer relatives only ate terrestrial plants and animals. Shellfish was one of the last additions to the human diet before domesticated plants and animals were introduced.”

Before, the earliest evidence for human use of marine resources and coastal habitats was dated about 125,000 years ago. “Our research shows that humans started doing this at least 40,000 years earlier. This could have very well been a response to the extreme environmental conditions they were experiencing,” he says.

“We also found what archaeologists call bladelets – little blades less than 10 millimetres in width, about the size of your little finger,” Marean says. “These could be attached to the end of a stick to form a point for a spear, or lined up like barbs on a dart – which shows they were already using complex compound tools. And, we found evidence that they were using pigments, especially red ochre, in ways that we believe were symbolic,” he describes.

Archaeologists view symbolic behavior as one of the clues that modern language may have been present. The earliest bladelet technology was previously dated to 70,000 years ago, near the end of the Middle Stone Age, and the modified pigments are the earliest securely dated and published evidence for pigment use.

“Coastlines generally make great migration routes,” Marean says. “Knowing how to exploit the sea for food meant these early humans could now use coastlines as productive home ranges and move long distances.”

Results reporting early use of coastlines are especially significant to scientists interested in the migration of humans out of Africa. Physical evidence that this coastal population was practising modern human behavior is particularly important to geneticists and physical anthropologists seeking to identify the progenitor population for modern humans.

“This evidence shows that Africa, and particularly southern Africa, was precocious in the development of modern human biology and behavior. We believe that on the far southern shore of Africa there was a small population of modern humans who struggled through this glacial period using shellfish and advanced technologies, and symbolism was important to their social relations. It is possible that this population could be the progenitor population for all modern humans,” Marean says.

ASU’s Institute for Social Science Research partners with archaeologists to create 3-D video

Along with the paper, also posted on Nature’s Web site is a video “The Cave 13B 3-D Experience.” A first for archaeology, the three-dimensional video representation of the stone age site and its remains, was produced with technical assistance from ASU’s Institute for Social Science Research in the College of Liberal Arts and Sciences. Erich Fisher of the University of Florida led the development group. The video is a fully georeferenced representation of the paleoscape and cave at Pinnacle Point. It allows the scientists to add field data and have it appear in the exact position it was found.

“The video is a recording of mouse movements within the computer model. Essentially, the computer model allows the user to fly into the landscape and enter the caves, walk around and add data. Our plan is to eventually make it available to the public over the World Wide Web with avatars who conduct tours of the cave. School children could hear about the story in the news and then log on and fly into the cave to see the result,” says Marean.

Due to global sea levels rising, it’s pretty obvious that many crucial coastal sites are going to be deep underwater, and either destroyed or inaccessible. These people were modern humans, with symbolic thought and sophisticated tools. And they were widespread by 164,000 years ago. To think they weren’t all over the Eurasian land mass by then is just ridiculous, as Red Sea wasn’t much more than a big, very salty puddle at times,  manageable by swimming or the simplest of rafts.

Call me crazy, but I’m thinking 100k is a much more likely date for an expansion. And probably earlier. It does call into question the validity of dates gained through mitochondrial DNA.

Jebel Irhoud,

Tiny shells may be world’s oldest beads.

Treasure hunt turns up ornaments that may be 100,000 years old

Shell beads
These are four views from different angles of a perforated Nassarius gibbosulus shell found at an archaeological site in Oued Djebbana, Algeria. The shell may be as much as 100,000 years old. The scale bar represents 1 centimeter, or half an inch.

82,000 year old beads from Morocco (above).

.So, we are all meant to be descended only from one small group of Africans that left via the Gate of Tears 60,000 years ago are we?

Studies on fossil specimens from a 160,000-year-old child reveal more clues to the evolution of modern humans. Tests on remains from a child show it was growing as slowly as an eight-year-old child would today. This is the earliest evidence of a prolonged childhood in our modern human ancestors, Homo sapiens .‘This paper certainly provides evidence of a pattern of growth like our own, and this is perhaps not surprising, as there is a very modern-looking child’s skull from Herto in Ethiopia,’ says Chris Stringer, human origins expert at the Natural History Museum.

Frontal view of cast of adult male Homo sapiens from Jebel Irhoud in Morocco.

Frontal view of cast of adult male Homo sapiens from Jebel Irhoud in Morocco.

Three modern human skulls from Herto in Ethiopia were dated and described in 2003 and at 160,000 years they are some of the oldest examples of modern humans, Homo sapiens .

‘What is also interesting is that in this paper is the first direct date on the material from Irhoud (Morocco), placing it at about the same age as the Herto finds – about 160,000 years old. This allows us to directly compare these samples from people living across North Africa, Morocco and Ethiopia.’

Testing bones and teeth

The team of scientists carried out various tests on the fossilised bones and teeth. They looked for molar teeth in the jaw that may not have erupted, an important clue to the development of a child. And a powerful X-ray technique on a fossilised tooth revealed microscopic growth lines hidden inside. This shows the tooth was immature and had grown slowly, the same as an eight-year-old child’s would today.

Long childhoods

Humans have the longest childhood of all primates, and this feature in nature is associated with complex social structures, as the brain has longer to develop during childhood.

More ancient human ancestors grew up much faster. For example Australopithecines , living about 3 million years ago, may have reached adulthood by the age of 12.

Jebel Irhoud site

The fossil remains of this child, who was about eight years old, were discovered in the Jebel Irhoud site in Morocco in 1968. ‘This is a very important site and has often been neglected in the discussions of modern human origins,’ says Chris. ‘In my own case, studies of an adult skull from this site over 30 years ago was one of the factors that led me to the view that our species had evolved in Africa.’

‘While I think that the Irhoud material is probably less ‘modern’ overall than do the authors of this paper, nevertheless these fossils could certainly represent populations ancestral to modern humans, and they show that North Africa may well have played a significant part in our origins,’ concludes Chris.
A team from the Max Planck Institute of Evolutionary Anthropology in Germany and the European Synchrotron Radiation Facility in France carried out the research.

The research is published in the Proceedings of the National Academy of Sciences .