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Back to the garden... origins of mankind.
Summer 2017Cover StoriesDaily News
When ancient fossil DNA isn't available, ancient glycans may help trace human evolution
Mon, Sep 11, 2017


[Image: when-ancient-fossil-dna-isn-t-available-...=1000&q=70]
UNIVERSITY OF CALIFORNIA - SAN DIEGO—Ancient DNA recovered from fossils is a valuable tool to study evolution and anthropology. Yet ancient fossil DNA from earlier geological ages has not been found yet in any part of Africa, where it's destroyed by extreme heat and humidity. In a potential first step at overcoming this hurdle, researchers at University of California San Diego School of Medicine and Turkana Basin Institute in Kenya have discovered a new kind of glycan—a type of sugar chain—that survives even in a 4 million-year-old animal fossil from Kenya, under conditions where ancient DNA does not.
While ancient fossils from hominins (human ancestors and extinct relatives) are not yet available for glycan analysis, this proof-of-concept study, published September 11 in Proceedings of the National Academy of Sciences, may set the stage for unprecedented explorations of human origins and diet.
"In recent decades, many new hominin fossils were discovered and considered to be the ancestors of humans," said Ajit Varki, MD, Distinguished Professor of Medicine and Cellular and Molecular Medicine at UC San Diego School of Medicine. "But it's not possible that all gave rise to modern humans—it's more likely that there were many human-like species over time, only one from which we descended. This new type of glycan we found may give us a better way to investigate which lineage is ours, as well as answer many other questions about our evolution, and our propensity to consume red meat."
Glycans are complex sugar chains on the surfaces of all cells. They mediate interaction between cells and the environment, and often serve as docking sites for pathogens. For millions of years, the common ancestors of humans and other apes shared a particular glycan known as Neu5Gc. Then, for reasons possibly linked to a malarial parasite that exploited Neu5Gc as a means to establish infection, a mutation that probably occurred between 2 and 3 million years ago inactivated the human gene encoding the enzyme that makes the molecule. The loss of Neu5Gc amounted to a radical molecular makeover of human ancestral cell surfaces and might have created a fertility barrier that expedited the divergence of the lineage leading to humans.
Today, chimpanzees and most other mammals still produce Neu5Gc. In contrast, only trace amounts can be detected in human blood and tissue—not because we make Neu5Gc, but, according to a previous study by Varki's team, because we accumulate the glycan when eating Neu5Gc rich red meat. Humans mount an immune response to this non-native Neu5Gc, possibly aggravating diseases such as cancer.
In their latest study, Varki and team found that, as part of its natural breakdown, a signature part of Neu5Gc is also incorporated into chondroitin sulfate (CS), an abundant component in bone. They detected this newly discovered molecule, called Gc-CS, in a variety of mammalian samples, including easily detectable amounts in chimpanzee bones and mouse tissues.
Like Neu5Gc, they found that human cells and serum have only trace amounts of Gc-CS—again, likely from red meat consumption. The researchers backed up that assumption with the finding that mice engineered to lack Neu5Gc and Gc-Cs (similar to humans) had detectable Gc-CS only when fed Neu5Gc-containing chow.
Curious to see how stable and long-lasting Gc-CS might be, Varki bought a relatively inexpensive 50,000-year-old cave bear fossil at a public fossil show and took it back to the lab. Despite its age, the fossil indeed contained Gc-CS.
That's when Varki turned to a long-time collaborator—paleoanthropologist and famed fossil hunter Meave Leakey, PhD, of Turkana Basin Institute of Kenya and Stony Brook University. Knowing that researchers need to make a very strong case before they are given precious ancient hominin fossil samples, even for DNA analysis, Leakey recommended that the researchers first prove their method by detecting Gc-CS in even older animal fossils. To that end, with the permission of the National Museums of Kenya, she gave them a fragment of a 4-million-year-old fossil from a buffalo-like animal recovered in the excavation of a bone bed at Allia Bay, in the Turkana Basin of northern Kenya. Hominin fossils were also recovered from the same horizon in this bone bed.
Varki and team were still able to recover Gc-CS in these much older fossils. If they eventually find Gc-Cs in ancient hominin fossils as well, the researchers say it could open up all kinds of interesting possibilities.
"Once we've refined our technique to the point that we need smaller sample amounts and are able to obtain ancient hominin fossils from Africa, we may eventually be able to classify them into two groups—those that have Gc-CS and those that do not. Those that lack the molecule would mostly likely belong to the lineage that led to modern humans," said Varki, who is also adjunct professor at the Salk Institute for Biological Studies and co-director of the UC San Diego/Salk Center for Academic Research and Training in Anthropogeny (CARTA).
In a parallel line of inquiry, Varki hopes Gc-CS detection will also reveal the point in evolution when humans began consuming large amounts of red meat.
"It's possible we'll one day find three groups of hominin fossils—those with Gc-CS before the human lineage branched off, those without Gc-CS in our direct lineage, and then more recent fossils in which trace amounts of Gc-CS began to reappear when our ancestors began eating red meat," Varki said. "Or maybe our ancestors lost Gc-CS more gradually, or only after we began eating red meat. It will be interesting to see, and we can begin asking these questions now that we know we can reliably find Gc-CS in ancient fossils in Africa."
Leakey is also hopeful about the role Gc-CS could play in the future, as an alternative to current approaches.
"Because DNA rapidly degrades in the tropics, genetic studies are not possible in fossils of human ancestors older than only a few thousand years," she said. "Therefore such ancient glycan studies have the potential to provide a new and important method for the investigation of human origins."
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[Image: 36964759806_c5bdb49606.jpg]
Partial upper jaw of Australopithecus anamensis, a primitive hominin, recovered from the bone bed excavated at the Allia Bay site. Photo courtesy of Meave Leakey, PhD
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[Image: 36964766076_4a381efe71.jpg]
Excavation of the bone bed at the Allia Bay site, East Turkana, in 1996. A cross section of the bone bed can be seen passing diagonally from the center of the image to the right hand corner. This is the site where researchers collected a 4-million-year-old bovid fossil that contained Gc-CS. Photo courtesy of Meave Leakey, PhD.
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Co-authors of this study also include: Anne K. Bergfeld, Roger Lawrence, Sandra L. Diaz, Oliver M.T. Pearce, Darius Ghaderi, and Pascal Gagneux, all at UC San Diego.
Article Source: University of California, San Diego news release


http://popular-archaeology.com/issue/summer-2017/article/when-ancient-fossil-dna-isn-t-available-ancient-glycans-may-help-trace-human-evolution
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People may have lived in Brazil more than 20,000 years ago
BY 
BRUCE BOWER 

7:00AM, SEPTEMBER 5, 2017


[Image: 090117_BB_south-america_main.jpg][img=788x0]https://www.sciencenews.org/sites/default/files/2017/09/main/blogposts/090117_BB_south-america_main.jpg[/img]
EARLY ARRIVALS  Excavations at a Brazilian rock shelter near the center of South America (left) suggest that humans hunted giant sloths there more than 20,000 years ago. Ancient people used some sloth bones unearthed at the site (right, top and bottom) as personal ornaments, based on notches and holes in those finds.

D. VIALOU ET AL/ANTIQUITY 2017
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People hunted giant sloths in the center of South America around 23,120 years ago, researchers say — a find that adds to evidence that humans reached South America well before Clovis hunters roamed North America roughly 13,000 years ago.
Evidence of people’s presence at Santa Elina rock shelter, located in a forested part of central-west Brazil, so long ago raises questions about how people first entered South America. Early settlers may have floated down the Pacific Coast in canoes before heading 2,000 kilometers east to the remote rock shelter, or they might have taken an inland route from North America, archaeologist Denis Vialou of the National Museum of Natural History in Paris and his colleagues report in the August Antiquity. Other South American sites reportedly occupied by Stone Age humans lie much closer to the coast than Santa Elina does.
Excavations at Santa Elina from 1984 to 2004 revealed three sediment layers containing numerous stone artifacts and bones of giant sloths called Glossotherium. Sloth remains included small, bony plates from the skin that humans made into ornaments of some kind by adding notches and holes. Sediment layers also contained remains of hearths.
Three dating methods, applied to charcoal particles, sediment and sloth bones, indicate that people first reached Santa Elina more than 20,000 years ago. Humans again visited the rock shelter from around 10,120 to 2,000 years ago, the researchers say.[/size]


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Editor's note: This story was updated September 12, 2017, to correct the location of Santa Elina. It's in central-west, not eastern, Brazil.

Citations
D. Vialou et al. Peopling South America’s center: the late Pleistocene site of Santa ElinaAntiquity. Vol. 91, August 2017, p. 865. doi:10.15184/aqy.2017.101.
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Further Reading
B. Bower. People roamed tip of South America 18,500 years ago. Science News. Vol. 188, December 26, 2015, p. 10.
B. Bower. Disputed finds put humans in South America 22,000 years ago. Science News. Vol. 183, April 20, 2013, p. 9.


https://www.sciencenews.org/blog/science-ticker/stone-age-people-brazil-20000-years-ago
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Ancient human DNA in sub-Saharan Africa lifts veil on prehistory
September 21, 2017

[Image: ancienthuman.png]
Mount Hora in Malawi, where the oldest DNA in the study, from a woman who lived more than 8,000 years ago, was obtained. Credit: Jessica C. Thompson/Emory University
The first large-scale study of ancient human DNA from sub-Saharan Africa opens a long-awaited window into the identity of prehistoric populations in the region and how they moved around and replaced one another over the past 8,000 years.


The findings, published Sept. 21 in Cell by an international research team led by Harvard Medical School, answer several longstanding mysteries and uncover surprising details about sub-Saharan African ancestry—including genetic adaptations for a hunter-gatherer lifestyle and the first glimpses of population distribution before farmers and animal herders swept across the continent about 3,000 years ago.
"The last few thousand years were an incredibly rich and formative period that is key to understanding how populations in Africa got to where they are today," said David Reich, professor of genetics at HMS and a senior associate member of the Broad Institute of MIT and Harvard. "Ancestry during this time period is such an unexplored landscape that everything we learned was new."
Reich shares senior authorship of the study with Ron Pinhasi of the University of Vienna and Johannes Krause of the Max Planck Institute for the Science of Human History and the University of Tübingen in Germany.
"Ancient DNA is the only tool we have for characterizing past genomic diversity. It teaches us things we don't know about history from archaeology and linguistics and can help us better understand present-day populations," said Pontus Skoglund, a postdoctoral researcher in the Reich lab and the study's first author. "We need to ensure we use it for the benefit of all populations around the world, perhaps especially Africa, which contains the greatest human genetic diversity in the world but has been underserved by the genomics community."
Long time coming
Although ancient-DNA research has revealed insights into the population histories of many areas of the world, delving into the deep ancestry of African groups wasn't possible until recently because genetic material degrades too rapidly in warm, humid climates.
Technological advances—including the discovery by Pinhasi and colleagues that DNA persists longer in small, dense ear bones—are now beginning to break the climate barrier. Last year, Reich and colleagues used the new techniques to generate the first genome-wide data from the earliest farmers in the Near East, who lived between 8,000 and 12,000 years ago.

In the new study, Skoglund and team, including colleagues from South Africa, Malawi, Tanzania and Kenya, coaxed DNA from the remains of 15 ancient sub-Saharan Africans. The individuals came from a variety of geographic regions and ranged in age from about 500 to 8,500 years old.
The researchers compared these ancient genomes—along with the only other known ancient genome from the region, previously published in 2015—against those of nearly 600 present-day people from 59 African populations and 300 people from 142 non-African groups.
With each analysis, revelations rolled in.
"We are peeling back the first layers of the agricultural transition south of the Sahara," said Skoglund. "Already we can see that there was a whole different landscape of populations just 2,000 or 3,000 years ago."
[Image: ancientdnada.png]
This visual abstract depicts the findings of Skoglund et al. In their paper, the prehistory of African populations is explored by genome-wide analysis of 16 human remains providing insight into lineages, admixture, and genomicadaptions. Credit: Skoglund et al./Cell 2017
Genomic time-lapse
Almost half of the team's samples came from Malawi, providing a series of genomic snapshots from the same location across thousands of years.
The time-series divulged the existence of an ancient hunter-gatherer population the researchers hadn't expected.
When agriculture spread in Europe and East Asia, farmers and animal herders expanded into new areas and mixed with the hunter-gatherers who lived there. Present-day populations thus inherited DNA from both groups.
The new study found evidence for similar movement and mixing in other parts of Africa, but after farmers reached Malawi, hunter-gatherers seem to have disappeared without contributing any detectable ancestry to the people who live there today.
"It looks like there was a complete population replacement," said Reich. "We haven't seen clear evidence for an event like this anywhere else."
The Malawi snapshots also helped identify a population that spanned from the southern tip of Africa all the way to the equator about 1,400 years ago before fading away. That mysterious group shared ancestry with today's Khoe-San people in southern Africa and left a few DNA traces in people from a group of islands thousands of miles away, off the coast of Tanzania.
"It's amazing to see these populations in the DNA that don't exist anymore," said Reich. "It's clear that gathering additional DNA samples will teach us much more."
"The Khoe-San are such a genetically distinctive people, it was a surprise to find a closely related ancestor so far north just a couple of thousand years ago," Reich added.
The new study also found that West Africans can trace their lineage back to a human ancestor that may have split off from other African populations even earlier than the Khoe-San.
Missing links
The research similarly shed light on the origins of another unique group, the Hadza people of East Africa.
"They have a distinct appearance, language and genetics, and some people speculated that, like the Khoe-San, they might represent a very early diverging group from other African populations," said Reich. "Our study shows that instead, they're somehow in the middle of everything."
The Hadza, according to genomic comparisons, are today more closely related to non-Africans than to other Africans. The researchers hypothesize that the Hadza are direct descendants of the group that migrated out of Africa, and possibly spread within Africa as well, after about 50,000 years ago.
Another discovery lay in wait in East Africa.
Scientists had predicted the existence of an ancient population based on the observation that present-day people in southern Africa share ancestry with people in the Near East. The 3,000-year-old remains of a young girl in Tanzania provided the missing evidence.
Reich and colleagues suspect that the girl belonged to a herding population that contributed significant ancestry to present-day people from Ethiopia and Somalia down to South Africa. The ancient population was about one-third Eurasian, and the researchers were able to further pinpoint that ancestry to the Levant region.
"With this sample in hand, we can now say more about who these people were," said Skoglund.
The finding put one mystery to rest while raising another: Present-day people in the Horn of Africa have additional Near Eastern ancestry that can't be explained by the group to which the young girl belonged.
Natural selection
Finally, the study took a first step in using ancient DNA to understand genetic adaptation in African populations.
It required "squeezing water out of a stone" because the researchers were working with so few ancient samples, said Reich, but Skoglund was able to identify two regions of the genome that appear to have undergone natural selection in southern Africans.
One adaptation increased protection from ultraviolet radiation, which the researchers propose could be related to life in the Kalahari Desert. The other variant was located on genes related to taste buds, which the researchers point out can help people detect poisons in plants.
The researchers hope that their study encourages more investigation into the diverse genetic landscape of human populations in Africa, both past and present. Reich also said he hopes the work reminds people that African history didn't end 50,000 years ago when groups of humans began migrating into the Near East and beyond.
"The late Stone Age in Africa is like a black hole, research-wise," said Reich. "Ancient DNA can address that gap."
[Image: 1x1.gif] Explore further: DNA analyses reveal genetic identities of world's first farmers
More information: "Reconstructing Prehistoric African Population Structure" Cell (2017). DOI: 10.1016/j.cell.2017.08.049http://www.cell.com/cell/fulltext/S0092-8674(17)31008-5 
Journal reference: Cell [Image: img-dot.gif] [Image: img-dot.gif]
Provided by: Harvard Medical School



Read more at: https://phys.org/news/2017-09-ancient-human-dna-sub-saharan-africa.html#jCp[/url][url=https://phys.org/news/2017-09-ancient-human-dna-sub-saharan-africa.html#jCp]
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This thread rewrites olde school ANU.

This thread is to discuss and update our knowledge on the origins of mankind.

The fascinating subject of our origins has recently been populated with anomalous new hominid species.

Living literally alongside us yet now they all seem gone.

So much new information has arisen that itz time for a total update for 2016. 2017

What we learned in school can for the most part either be used as a general frame-work and set of loose guidelines or just go ahead and toss all that bull-shit in the trash and just start fresh here.
Quote:[Image: fossil-footprints-stolen-660x330.jpg]

Local high school teacher arrested for fossil footprints theft in Crete
September 15, 2017 ArcheologyCulture Leave a comment

What we learned in school can for the most part either be used as a general frame-work and set of loose guidelines or just go ahead and toss all that bull-shit in the trash and just start fresh here.


[/url]Share2

A local high school teacher has been arrested for the theft of fossil footprints in Kasteli, Chania, on the island of Crete. A part of the stolen human-like footprints were found in the home of the 55-year-old who is a resident of Kissamos. Security cameras had recorded the thief when he was removing the 5.-7-million-year-old fossils last week.





Quote:"This means that modern humans emerged earlier than previously thought,"  Doh   says Mattias Jakobsson, population geneticist at Uppsala University who headed the project together with Stone Age archaeologist Marlize Lombard at the University of Johannesburg.

Read more at: https://phys.org/news/2017-09-modern-humans-emerged-years.html#jCp



Modern humans emerged more than 300,000 years ago, new study suggests
September 28, 2017

[Image: modernhumans.jpg]
Dr. Helena Malmström conducting on-site sampling of bone matrial in a mobil sampling lab. Credit: Uppsala University
A genomic analysis of ancient human remains from KwaZulu-Natal revealed that southern Africa has an important role to play in writing the history of humankind. A research team from Uppsala University, Sweden, the Universities of Johannesburg and the Witwatersrand, South Africa, presents their results in the September 28th early online issue of Science.



The team sequenced the genomes of seven individuals who lived in southern Africa 2300-300 years ago. The three oldest individuals dating to 2300-1800 years ago were genetically related to the descendants of the southern Khoe-San groups, and the four younger individuals who lived 500-300 years ago were genetically related to current-day South African Bantu-speaking groups. "This illustrates the population replacement that occurred in southern Africa," says co-first author Carina Schlebusch, population geneticist at Uppsala University.
The authors estimate the divergence among modern humans to have occurred between 350,000 and 260,000 years ago, based on the ancient Stone Age hunter-gatherer genomes. The deepest split time of 350,000 years ago represents a comparison between an ancient Stone Age hunter-gatherer boy from Ballito Bay on the east coast of South Africa and the West African Mandinka. "This means that modern humans emerged earlier than previously thought," says Mattias Jakobsson, population geneticist at Uppsala University who headed the project together with Stone Age archaeologist Marlize Lombard at the University of Johannesburg.
The fossil record of east Africa, and in particular the Omo and Herto fossils, have often been used to set the emergence of anatomically modern humans to about 180,000 years ago. The deeper estimate for modern human divergence at 350,000-260,000 years ago coincides with the Florisbad and Hoedjiespunt fossils, contemporaries of the small-brained Homo naledi in southern Africa. "It now seems that at least two or three Homo species occupied the southern African landscape during this time period, which also represents the early phases of the Middle Stone Age," says Marlize Lombard. It will be interesting to see in future if we find any evidence of interaction between these groups.
"We did not find any evidence of deep structure or archaic admixture among southern African Stone Age hunter-gatherers. Instead, we see some evidence for deep structure in the West African population, but that affects only a small fraction of their genome and is about the same age as the deepest divergence among all humans," says Mattias Jakobsson.
[Image: 59ccce67ee96a.jpg]
Demographic model of African history and estimated divergences. Vertical colored lines represent migration, with down-pointing triangles representing admixture into another group. Southern African hunter-gatherers are shown by red symbols, and Iron Age farmers as green symbols. Extracted from figure 3. Credit: Uppsala University
The authors also found that all current-day Khoe-San populations admixed with migrant East African pastoralists a little over a thousand years ago. "We could not detect this widespread East African admixture previously since we did not have an un-admixed San group to use as reference. Now that we have access to ancient DNA of people who lived on the landscape before the East African migration, we are able to detect the admixture percentages in all San groups. The admixture percentages in the Khoekhoe, historically identified as pastoralists, are higher than previously estimated," says Carina Schlebusch.


Of the Iron Age individuals, three carry at least one Duffy null allele, protecting against malaria, and two have at least one sleeping-sickness-resistance variant in the APOL1 gene. The Stone Age individuals do not carry these protective alleles. "This tells us that Iron Age farmers carried these disease-resistance variants when they migrated to southern Africa," says co-first author Helena Malmström, archaeo-geneticist at Uppsala University.
Marlize Lombard said that "archaeological deposits dating to the time of the split by 350,000-260,000 years ago, attest to South Africa being populated by tool-making hunter-gatherers at the time. Although human fossils are sparse, those of Florisbad and Hoedjiespunt are seen as transitional to modern humans." These fossils may therefore be ancestral to the Ballito Bay boy and other San hunter-gatherers who lived in southern Africa 2000 years ago. 3E3E3E...3E3E3E...
[Image: stoneagechil.jpg]
Marlize Lombard (University of Johannesburg) excavating at Sibudu Cave (under the direction of Prof Lyn Wadley, University of the Witwatersrand), about 40 km southeast of Ballito Bay where the boy was found. The cave was intermittently occupied by humans from at least 77 000 years ago who might have been ancestral to the Ballito boy. Credit: Lyn Wadley, University of the Witwatersrand.
The transition from archaic to modern humans might not have occurred in one place in Africa but in several, including southern Africa and northern Africa as recently reported. "Thus, both palaeo-anthropological and genetic evidence increasingly points to multiregional origins of anatomically modern humans in Africa, i.e. Homo sapiens did not originate in one place in Africa, but might have evolved from older forms in several places on the continent with gene flow between groups from different places," says Carina Schlebusch.
"It is remarkable that we can now sequence entire genomes of ancient human remains from tropical areas, such as the southeast coast of South Africa," says Helena Malmström. This is promising for our several ongoing investigations in Africa.
Cumulatively these findings shed new light on our species' deep African history and show that there is still much more to learn about our process of becoming modern humans and that the interplay between genetics and archaeology has an increasingly important role to play.
[Image: 1x1.gif] Explore further: Lactase persistence alleles reveal ancestry of southern African Khoe pastoralists
More information: C. Schlebusch el al., "Southern African ancient genomes estimate modern human divergence to 350,000 to 260,000 years ago," Science (2017). science.sciencemag.org/lookup/ … 1126/science.aao6266 
Journal reference: Science [Image: img-dot.gif] [Image: img-dot.gif]
Provided by: Uppsala University



Read more at: https://phys.org/news/2017-09-modern-hum...s.html#jCp[url=https://phys.org/news/2017-09-modern-humans-emerged-years.html#jCp]
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Discovery of 10,000-year-old petroglyph in Norway described as 'sensational'
[Image: 94f529faea2c906b06af3682161e306666f0897f...3d79fd.jpg]

Photo: Jan Magne Gjerde / Universitetet i Tromsø / NTB scanpix
A petroglyph of a boat discovered in northern Norway has been estimated to date back 10,000 to 11,000 years.
[/url]The petroglyph was discovered by retired geologist Ingvar Lindahl at Efjorden in the Nordland county, reports broadcaster [url=https://www.nrk.no/nordland/sensasjonelt-funn_-_-dette-er-trolig-verdens-eldste-avbildning-av-bat-1.13706728]NRK.
Analysis has now estimated the petroglyph, which depicts a boat, to be between 10,000 and 11,000 years old, according to the report.
“This is an extremely important development, a global sensation in fact, and will enter the history of research in a very, very big way,” archaeologist Jan Magne Gjerde of Tromsø University told NRK.
The petroglyph was dated using estimates of the height of the water level against the rock on which it is carved, Gjerde said. Water levels in the region were higher during the Stone Age than they are today.
“The boat is a little over four metres long. You can see the keel line and the railing line, and as you move forward you can see a really beautiful finish, forming the boat’s bows,” Gjerde told NRK, adding that the find was “incredibly exciting”.

The petroglyph is possibly the oldest in the world depicting a boat, the archaeologist told NRK.

https://www.thelocal.no/20170927/discovery-of-10000-year-old-petroglyph-in-norway-described-as-sensational

garden...
Earliest Evidence of Domesticated Sorghum Discovered

Sep 28, 2017 by News Staff / Source

Sorghum was domesticated from its wild ancestor more than 5,000 years ago, according to archaeological evidence uncovered by University College London archaeologist Dorian Fuller and colleagues in Sudan.
[Image: image_5271_1-Sorghum.jpg][img=580x0]http://cdn.sci-news.com/images/2017/09/image_5271_1-Sorghum.jpg[/img]
Sorghum (Sorghum bicolor). Image credit: Pethan, Botanical Gardens, Utrecht University / CC BY-SA 3.0.

Sorghum (Sorghum bicolor) is a native African grass that was utilized for thousands of years by prehistoric peoples, and emerged as one of the world’s five most important cereal crops, along with rice, wheat, barley, and maize.
For a half century scientists have hypothesized that native African groups were domesticating sorghum outside the winter rainfall zone of the ancient Egyptian Nile Valley — where wheat and barley cereals were predominant — in the semi-arid tropics of Africa, but no archaeological evidence existed.
The newest evidence comes from an archaeological site near Kassala in eastern Sudan, dating from 3500 to 3000 BC, and is associated with the Butana Group culture.
“This new discovery in eastern Sudan reveals that during the 4th millennium BC, peoples of the Butana Group were intensively cultivating wild stands of sorghum until they began to change the plant genetically into domesticated morphotypes,” Dr. Fuller and co-authors said.
[Image: image_5271_2-Sorghum.jpg][img=580x0]http://cdn.sci-news.com/images/2017/09/image_5271_2-Sorghum.jpg[/img]
Diagrammatic comparison of wild and domesticated sorghum. Image credit: D.Q. Fuller.

The researchers examined plant impressions within broken pottery from the largest Butana Group site, KG23.
“Ceramic sherds recovered from excavations undertaken by the Southern Methodist University Butana Project during the 1980s from the KG23 site were analyzed,” they explained.
“Examination of the plant impressions in the pottery revealed diagnostic chaff in which both domesticated and wild sorghum types were identified, thus providing archaeobotanical evidence for the beginnings of cultivation and emergence of domesticated characteristics within sorghum during the 4th millennium BC in eastern Sudan.”
“Along with the recent discovery of domesticated pearl millet in eastern Mali around 2500 BC, this discovery pushes back the process for domesticating summer rainfall cereals another thousand years in the Sahel, with sorghum, providing new evidence for the earliest known native African cultigen,” they said.
The research is published in the journal Current Anthropology.
_____
Frank Winchell et al. Evidence for Sorghum Domestication in Fourth Millennium BC Eastern Sudan: Spikelet Morphology from Ceramic Impressions of the Butana Group. Current Anthropology, published online September 20, 2017; doi: 10.1086/693898

http://www.sci-news.com/archaeology/earliest-evidence-domesticated-sorghum-05271.html

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...
fantastic new science and information!
Thanks!
I could barely see the boat in the image supplied, 
and only after several tries.
10,000 years old.
And the western science tries to tell us,
that humans didn't travel across the oceans to the Americas before Columbus.

Columbus was the last human explorer .... to be the first to do it.

The sorghum science discovery was excellent as well.
and "pearl millet" in eastern Mali.

Most of the ancient grains like millet and amaranth etc., 
had high levels of proanthocyandins,
found in grape seed extract.
Modern grains have none of that excellent antioxidant,
which aids in rounding up free radicals roaming the bloodstream and body systems.
Anti-cancer activity as well.

...
Reply
New study suggests that last common ancestor of humans and apes was smaller than thought
October 12, 2017

New research suggests that the last common ancestor of apes—including great apes and humans—was much smaller than previously thought, about the size of a gibbon. The findings, published today in the journal Nature Communications, are fundamental to understanding the evolution of the human family tree.

"Body size directly affects how an animal relates to its environment, and no trait has a wider range of biological implications," said lead author Mark Grabowski, a visiting assistant professor at the Eberhard Karls University of Tübingen in Germany who conducted the work while he was a postdoctoral fellow in the American Museum of Natural History's Division of Anthropology. "However, little is known about the size of the last common ancestor of humans and all living apes. This omission is startling because numerous paleobiological hypotheses depend on body size estimates at and prior to the root of our lineage."
Among living primates, humans are most closely related to apes, which include the lesser apes (gibbons) and the great apes (chimpanzees, gorillas, and orangutans). These "hominoids" emerged and diversified during the Miocene, between about 23 million to 5 million years ago. Because fossils are so scarce, researchers do not know what the last common ancestors of living apes and humans looked like or where they originated.
To get a better idea of body mass evolution within this part of the primate family tree, Grabowski and coauthor William Jungers from Stony Brook University compared body size data from modern primates, including humans, to recently published estimates for fossil hominins and a wide sample of fossil primates including Miocene apes from Africa, Europe, and Asia. They found that the common ancestor of apes was likely small, probably weighing about 12 pounds, which goes against previous suggestions of a chimpanzee-sized, chimpanzee-like ancestor.
Among other things, the finding has implications for a behavior that's essential for large, tree-dwelling primates: it implies that "suspensory locomotion," overhand hanging and swinging, arose for other reasons than the animal simply getting too big to walk on top of branches. The researchers suggest that the ancestor was already somewhat suspensory, and larger body size evolved later, with both adaptations occurring at separate points. The development of suspensory locomotion could have been part of an "arms race" with a growing number of monkey species, the researchers said. Branch swinging allows an animal to get to a prized and otherwise inaccessible food—fruit on the edges of foliage—and larger body would let them engage in direct confrontation with monkeys when required.
The new research also reveals that australopiths, a group of early human relatives, were actually on average smaller than their ancestors, and that this smaller size continued until the arrival of Homo erectus.
"There appears to be a decrease in overall body size within our lineage, rather than size simply staying the same or getting bigger with time, which goes against how we generally think about evolution," Grabowski said.
[Image: 1x1.gif] Explore further: Human ancestor was less-chimp-like than thought: study
More information: Mark Grabowski et al, Evidence of a chimpanzee-sized ancestor of humans but a gibbon-sized ancestor of apes, Nature Communications (2017). DOI: 10.1038/s41467-017-00997-4 
Journal reference: Nature Communications [Image: img-dot.gif] [Image: img-dot.gif]
Provided by: American Museum of Natural History



Read more at: https://phys.org/news/2017-10-common-ancestor-humans-apes-smaller.html#jCp[/url]



Study identifies genes responsible for diversity of human skin colors
October 12, 2017

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Mursi woman of Nilo-Saharan ancestry. Nilo-Saharan pastoralist populations possess some of the darkest skin in Africa. Researchers from the University of Pennsylvania found mutations associated with both light and dark pigmentation in a genome-wide association study of diverse African populations. Credit: Alessia Ranciaro
Human populations feature a broad palette of skin tones. But until now, few genes have been shown to contribute to normal variation in skin color, and these had primarily been discovered through studies of European populations.

Now, a study of diverse African groups led by University of Pennsylvania geneticists has identified new genetic variants associated with skin pigmentation. The findings help explain the vast range of skin color on the African continent, shed light on human evolution and inform an understanding of the genetic risk factors for conditions such as skin cancer.
"We have identified new genetic variants that contribute to the genetic basis of one of the most strikingly variable traits in modern humans," said Sarah Tishkoff, a Penn Integrates Knowledge Professor and the David and Lyn Silfen University Professor in Genetics and Biology with appointments in the Perelman School of Medicine and School of Arts and Sciences. "When people think of skin color in Africa most would think of darker skin, but we show that within Africa there is a huge amount of variation, ranging from skin as light as some Asians to the darkest skin on a global level and everything in between. We identify genetic variants affecting these traits and show that mutations influencing light and dark skin have been around for a long time, since before the origin of modern humans."
The findings are published in the journal Science. Tishkoff, senior author, collaborated with first author and lab member Nicholas Crawford, a postdoctoral fellow, and a multi-institutional, international team.
Tishkoff has long studied the genetics of African populations, looking at traits such as height, lactose tolerance, bitter-taste sensitivity and high-altitude adaptation. Skin color emerged as a trait of interest from her experience working on the continent and seeing the diversity present across groups.
"Skin color is a classic variable trait in humans, and it's thought to be adaptive," Tishkoff said. "Analysis of the genetic basis of variation in skin color sheds light on how adaptive traits evolve, including those that play a role in disease risk."

Both light and dark skin pigmentations confer benefits: Darker skin, for example, is believed to help prevent some of the negative impacts of ultraviolet light exposure, while lighter skin is better able to promote synthesis of vitamin D in regions with low ultraviolet light exposure.

To objectively capture the range of skin pigmentation in Africa, Tishkoff and colleagues used a color meter to measure the light reflectance of the skin of more than 2,000 Africans from ethnically and genetically diverse populations. They took the measurement from the inner arm, when sun exposure is minimal. The measurements can be used to infer levels of the skin pigment melanin. They obtained a range of measurements; the darkest skin was observed in Nilo-Saharan pastoralist populations in eastern Africa, and the lightest skin was observed in San hunter-gatherer populations in southern Africa.

The researchers obtained genetic information from nearly 1,600 people, examining more than 4 million single nucleotide polymorphisms across the genome, places where the DNA code may differ by one "letter." From this dataset the researchers were able to do a genome-wide association study and found four key areas of the genome where variation closely correlated with skin color differences.

[Image: pennledstudy.jpg]

In a first-of-its-kind study, University of Pennsylvania researchers studied the genetics behind skin pigmentation of diverse African populations, finding new genetic variants associated with skin color. Here, senior research scientist …more

The region with the strongest associations was in and around the SLC24A5 gene, one variant of which is known to play a role in light skin color in European and some southern Asian populations and is believed to have arisen more than 30,000 years ago. This variant was common in populations in Ethiopia and Tanzania that were known to have ancestry from southeast Asia and the Middle East, suggesting it was carried into Africa from those regions and, based on its frequency, may have been positively selected.

Another region, which contains the MFSD12 gene, had the second strongest association to skin pigmentation. This gene is expressed at low levels in depigmented skin in individuals with vitiligo, a condition where the skin loses pigment in some areas.

"I still rememeber the 'ah ha!' moment when we saw this gene was associated with vitiligo," said Crawford. "That's when we knew we'd found something new and exciting."

The team found that mutations in and around this gene that were associated with dark pigmentation were present at high frequencies in populations of Nilo-Saharan ancestry, who tend to have very dark skin, as well as across sub-Saharan populations, except the San, who tend to have lighter skin. They also identified these variants, as well as others associated with dark skin pigmentation, in South Asian Indian and Australo-Melanesian populations, who tend to have the darkest skin coloration outside of Africa.

"The origin of traits such as hair texture, skin color and stature, which are shared between some indigenous populations in Melanesia and Australia and some sub-Saharan Africans, has long been a mystery." Tishkoff said. "Some have argued it's because of convergent evolution, that they independently evolved these mutations, but our study finds that, at genes associated with skin color, they have the identical variants associated with dark skin as Africans.

"Our data are consistent with a proposed early migration event of modern humans out of Africa along the southern coast of Asia and into Australo-Melanesia and a secondary migration event into other regions. However, it is also possible that there was a single African source population that contained genetic variants associated with both light and dark skin and that the variants associated with dark pigmentation were maintained only in South Asians and Australo-Melanesians and lost in other Eurasians due to natural selection."

Also of interest was that genetic variants at MFSD12OCA2, and HERC2 associated with light skin pigmentation were at highest frequency in the African San population, which has the oldest genetic lineages in the world, as well as in Europeans.

MFSD12 is highly expressed in melanocytes, the cells that produce melanin. To verify the gene's role in contributing to skin pigmentation, the researchers blocked expression of the gene in cells in culture and found an increase in production of eumelanin, the pigment type responsible for black and brown skin, hair and eye color. Knocking out the gene in zebrafish caused a loss of cells that produce yellow pigment. And in mice, knocking out the gene changed the color of their coat from agouti, caused by hairs with a red and yellow pigment, to a uniform gray by eliminating production of pheomelanin, a type of pigment also found in humans.

"Apart from one study showing that MFSD12 was associated with vitiligo lesions, we didn't know much else about it," said Crawford, "so these functional assays were really crucial."








 








Alessia Ranciaro and Simon Thompson. Credit: Alessia Ranciaro and Simon Thompson/University of Pennsylvania

"We went beyond most genome-wide association studies to do functional assays," Tishkoff said, "and found that knocking out MFSD12 dramatically impacted the pigmentation of fish and mice. It's pointing to this being a very conserved trait across species.

"We don't know exactly why, but blocking this gene causes a loss of pheomelanin production and an increase in eumelanin production," Tishkoff added. "We also showed that Africans have a lower level of MFSD12 expression, which makes sense, as low levels of the gene means more eumelanin production."

A collaborator on the work, Michael Marks, a professor in the departments of Pathology & Laboratory Medicine and of Physiology at Children's Hospital of Philadelphia and at Penn Medicine, demonstrated that the MFSD12 gene influences eumelanin pigmentation in a novel manner. Unlike other pigmentation genes, which are expressed mainly in melanosomes, the organelle where melanin is produced, MFSD12 is expressed in lysosomes, a distinct organelle from the melanosomes that produce eumelanin.

"Our results suggest there must be some kind of as-yet-uncharacterized form of cross-talk between lysosomes and the melanosomes that make eumelanins," Marks said. "Figuring out how this works might provide new ideas for ways to manipulate skin pigmentation for therapeutic means.

"In addition," Marks said, "the fact that loss of MFSD12 expression had opposite effects on the two types of melanins, increasing eumelanin production while suppressing pheomelanin, suggests that melanosomes that make pheomelanins might be more related to lysosomes than those that make eumelanin."

Additional associations with skin color were found in the OCA2 and HERC2 genes, which have been linked with skin, eye and hair color variation in Europeans, though the mutations identified are novel. Mutations in OCA2 also cause a form of albinism that is more common in Africans than in other populations. The researchers observed genetic variants in a neighboring gene, HERC2, which regulates the expression of OCA2. Within OCA2, they identified a variant common in Europeans and San that is associated with a shorter version of the protein, with an altered function. They observed a signal of balancing selection of OCA2, meaning that two different versions of the gene have been maintained, in this case for more than 600,000 years.

"What this tells us," Tishkoff said, "is there is likely some selective force maintaining these two alleles. It is likely that this gene is playing a role in other aspects of human physiology which are important."

A final genetic region the researchers found to be associated with skin pigmentation included genes that play a role in ultraviolet light response and melanoma risk. The top candidate gene in the region is DDB1, involved in repairing DNA after exposure to UV light.

"Africans don't get melanoma very often," Tishkoff said. "The variants near these genes are highest in populations who live in areas of the highest ultraviolet light intensity, so it makes sense that they may be playing a role in UV protection."

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A Ju/‘hoansi individual of the San who was not part of the study. Credit: Alessia Ranciaro

The mutations identified by the team play a role in regulating expression of DDB1 and other nearby genes.

"Though we don't yet know the mechanism by which DDB1 is impacting pigmentation, it is of interest to note that this gene, which is highly conserved across species, also plays a role in pigmentation in plants such as tomatoes," said Tishkoff.

The team saw evidence that this region of the genome has been a strong target of natural selection outside of Africa; mutations associated with light skin color swept to nearly 100 percent frequency in non-Africans, one of few examples of a "selective sweep" in all Eurasians; the age of the selective sweep was estimated to be around 60,000 to 80,000 years old, around the time of migration of modern humans out of Africa.

One additional takeaway from this work is a broader picture of the evolution of skin color in humans. Most of the genetic variants associated with light and dark pigmentation from the study appear to have originated more than 300,000 years ago, and some emerged roughly 1 million years ago, well before the emergence of modern humans. The older version of these variants in many cases was the one associated with lighter skin, suggesting that perhaps the ancestral state of humans was moderately pigmented rather than darkly pigmented skin.

"If you were to shave a chimp, it has light pigmentation," Tishkoff said, "so it makes sense that skin color in the ancestors of modern humans could have been relatively light. It is likely that when we lost the hair covering our bodies and moved from forests to the open savannah, we needed dark skin.

Tishkoff noted that the work underscores the diversity of African populations and the lack of support for biological notions of race.

"Many of the genes and new genetic variants we identified to be associated with skin color may never have been found outside of Africa, because they are not as highly variable," Tishkoff said. "There is so much diversity in Africa that's not often appreciated. There's no such thing as an African race. We show that skin color is extremely variable on the African continent and that it is still evolving. Further, in most cases the genetic variants associated with light skin arose in Africa."

[Image: 1x1.gif] Explore further: More traits associated with your Neandertal DNA

More information: N.G. Crawford el al., "Loci associated with skin pigmentation identified in African populations," Science (2017). science.sciencemag.org/lookup/ … 1126/science.aan8433 
Journal reference: Science [Image: img-dot.gif] [Image: img-dot.gif]
Provided by: University of Pennsylvania
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