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Humans started rice farming 9,000 years ago in China

Humans started rice farming 9,000 years ago in China | Amazing Science | Scoop.it
Chew on this: rice farming is a far older practice than we knew. In fact, the oldest evidence of domesticated rice has just been found in China, and it's about 9,000 years old.

 

The discovery, made by a team of archaeologists that includes University of Toronto Mississauga professor Gary Crawford, sheds new light on the origins of rice domestication and on the history of human agricultural practices.

 

Today, rice is one of most important grains in the world's economy, yet at one time, it was a wild plant...how did people bring rice into their world? This gives us another clue about how humans became farmers," says Crawford, an anthropological archaeologist who studies the relationships between people and plants in prehistory.

 

Working with three researchers from the Provincial Institute of Cultural Relics and Archaeology in Zhejiang Province, China, Crawford found the ancient domesticated rice fragments in a probable ditch in the lower Yangtze valley. They observed that about 30 per cent of the rice plant material - primarily bases, husks and leaf epidermis - were not wild, but showed signs of being purposely cultivated to produce rice plants that were durable and suitable for human consumption. Crawford says this finding indicates that the domestication of rice has been going on for much longer than originally thought. The rice plant remains also had characteristics of japonica rice, the short grain rice used in sushi that today is cultivated in Japan and Korea. Crawford says this finding clarifies the lineage of this specific rice crop, and confirms for the first time that it grew in this region of China.

 

Crawford and his colleagues spent about three years exploring the five-hectare archaeological dig site, called Huxi, which is situated in a flat basin about 100 meters above sea level. Their investigations were supported by other U of T Mississauga participants - anthropology professor David Smith and graduate students Danial Kwan and Nattha Cheunwattana. They worked primarily in early spring, fall and winter in order to avoid the late-spring wet season and excruciatingly hot summer months. Digging 1.5 meters below the ground, the team also unearthed artifacts such as sophisticated pottery and stone tools, as well as animal bones, charcoal and other plant seeds.

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5000-year-old beer-brewing kit found in China

5000-year-old beer-brewing kit found in China | Amazing Science | Scoop.it

Pottery from China has revealed the secrets of some of the oldest known beer makers, who may be linked to the rise of hierarchical societies in East Asia. We now have some idea of how the beer would have been made 5000 years ago, thanks to the residue left on an apparent beer-making toolkit uncovered in Shaanxi, northern China.

 

Jiajing Wang at the University of Stanford and colleagues found remnants of wide-mouthed pots, funnels and amphorae that would have been used for beer brewing, filtration and storage.

They analysed traces of the pottery’s former contents – microscopic starch fragments and phytoliths, silica structures found in cereal husks.

 

They identified these deposits as having come from broomcorn millet, Job’s tears, barley and tubers such as snake gourd root.

“Many of the starch grains were damaged, and the damage patterns precisely match the morphological changes developed during malting and mashing,” says Wang.

 

What’s more, the team found oxalates, organic compounds associated with the mashing and fermentation of cereals. The oldest chemically confirmed alcoholic beverage in the world, dating to 7000-6600 BC at nearby Jiahu in the Yellow River valley, was found by Pat McGovern at the University of Pennsylvania Museum of Archaeology and Anthropology.


Via Catherine Russell
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Animated map showing the dramatic spread of agriculture over the last 300 years

Animated map showing the dramatic spread of agriculture over the last 300 years | Amazing Science | Scoop.it

The map, produced by Radicalcartography.net shows the amount of land given over to agriculture around the world over the three centuries leading up to the year 2000.

 

The map shows that in 1700, outside of Europe and Asia there was a very small proportion of land being farmed. The 18th century saw an increase in arable land for use and the beginnings of a vast improvement in agricultural yields. New farming methods, such as four-field crop rotation, the increased use of fertilizer and increasing mechanization, opened up additional swaths of land for agriculture.

 

Technology developed in the First and Second Industrial Revolutions saw farming rapidly expand into previously untapped areas, such as the American Great Plains in the late 19th century and Argentina in the early 20th century.

 

Expansion and intensification of existing farming continued into recent decades, with Brazil and central India becoming more intensely farmed since the late 20th century.

 

Historian and cartographer Bill Rankin argues that existing arable land has become "more and more agricultural". It is estimated that the productivity of wheat in England went up from about 19 bushels per acre in 1720 to around 30 bushels by 1840.

 

In recent years intensification has increased and land expansion has slowed in the developed world. This is largely down to the increased use of fertilizer, which has improved production yields.


Via Neelima Sinha
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Lorraine Chaffer's curator insight, July 6, 2016 4:18 AM

NSW Syllabus
Sustainable Biomes

Content focus
Students

- examine the correlation between the world’s climatic zones and spatial distributions of biomes and their capacity to support food and non-food agricultural production

-  analyse the impact humans have on biomes in an effort to produce food and increase agricultural yields

 

GeoWorld 9 NSW
Chapter 2 Biomes produce food and non food products

Chapter 3 factors affecting agricultural yields

Chapter 4 Challenges to food production and management 

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Ancient DNA shows European wipe-out of early Americans

Ancient DNA shows European wipe-out of early Americans | Amazing Science | Scoop.it

The first large-scale study of ancient DNA from early American people has confirmed the devastating impact of European colonisation on the Indigenous American populations of the time.

Led by the University of Adelaide's Australian Centre for Ancient DNA (ACAD), the researchers have reconstructed a genetic history of Indigenous American populations by looking directly into the DNA of 92 pre-Columbian mummies and skeletons, between 500 and 8600 years old.

 

Published today in Science Advances, the study reveals a striking absence of the pre-Columbian genetic lineages in modern Indigenous Americans; showing extinction of these lineages with the arrival of the Spaniards.

 

"Surprisingly, none of the genetic lineages we found in almost 100 ancient humans were present, or showed evidence of descendants, in today's Indigenous populations," says joint lead author Dr Bastien Llamas, Senior Research Associate with ACAD. "This separation appears to have been established as early as 9000 years ago and was completely unexpected, so we examined many demographic scenarios to try and explain the pattern."

 

"The only scenario that fit our observations was that shortly after the initial colonisation, populations were established that subsequently stayed geographically isolated from one another, and that a major portion of these populations later became extinct following European contact. This closely matches the historical reports of a major demographic collapse immediately after the Spaniards arrived in the late 1400s."

 

The research team, which also includes members from the University of California at Santa Cruz (UCSC) and Harvard Medical School, studied maternal genetic lineages by sequencing whole mitochondrial genomes extracted from bone and teeth samples from 92 pre-Columbian--mainly South American--human mummies and skeletons.

 

The ancient genetic signals also provide a more precise timing of the first people entering the Americas--via the Beringian land bridge that connected Asia and the north-western tip of North America during the last Ice Age.

 

"Our genetic reconstruction confirms that the first Americans entered around 16,000 years ago via the Pacific coast, skirting around the massive ice sheets that blocked an inland corridor route which only opened much later," says Professor Alan Cooper, Director of ACAD. "They spread southward remarkably swiftly, reaching southern Chile by 14,600 years ago."

 

"Genetic diversity in these early people from Asia was limited by the small founding populations which were isolated on the Beringian land bridge for around 2400 to 9000 years," says joint lead author Dr Lars Fehren-Schmitz, from UCSC. "It was at the peak of the last Ice Age, when cold deserts and ice sheets blocked human movement, and limited resources would have constrained population size. This long isolation of a small group of people brewed the unique genetic diversity observed in the early Americans."

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Genetic mutation blocks spread of prion disease in Papua New Guinea

Genetic mutation blocks spread of prion disease in Papua New Guinea | Amazing Science | Scoop.it
Unknown mechanism helped some people in Papua New Guinea escape historic, deadly outbreak.


Scientists who study a rare brain disease that once devastated entire communities in Papua New Guinea have described a genetic variant that appears to stop misfolded proteins known as prions from propagating in the brain1.


Kuru was first observed in the mid-twentieth century among the Fore people of Papua New Guinea. At its peak in the late 1950s, the disease killed up to 2% of the group's population each year. Scientists later traced the illness to ritual cannibalism2, in which tribe members ate the brains and nervous systems of their dead. The outbreak probably began when a Fore person consumed body parts from someone who had sporadic Creutzfeldt-Jakob disease (CJD), a prion disease that spontaneously strikes about one person in a million each year.


Scientists have noted previously that some people seem less susceptible to prion diseases if they have an amino-acid substitution in a particular region of the prion protein — codon 1293. And in 2009, a team led by John Collinge — a prion researcher at University College London who is also the lead author of the most recent analysis — found another protective mutation among the Fore, in codon 1274.


The group's latest work, reported on 10 June in Nature1, shows that the amino-acid change that occurs at this codon, replacing a glycine with a valine, has a different and more powerful effect than the substitution at codon 129. The codon 129 variant confers some protection against prion disease only when it is present on one of the two copies of the gene that encodes the protein. But transgenic mice with the codon-127 mutation were completely resistant to kuru and CJD regardless of whether they bore one or two copies of it.


The researchers say that the mutation in codon 127 appears to confer protection by preventing prion proteins from becoming misshapen. “It is a surprise,” says Eric Minikel, a prion researcher at the Broad Institute in Cambridge, Massachusetts. “This was a story I didn’t expect to have another chapter.”


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Human migration out of Africa left its mark in mutations

Human migration out of Africa left its mark in mutations | Amazing Science | Scoop.it

When it comes to evolution, people tend to focus on the big driving force of natural selection, which latches on to helpful mutations while purging the harmful ones. But there are other processes that change the frequencies of mutations—everything from random drift to the founding of small isolated populations.


Looking at our own species' history, we would expect to see some of this in action. After modern humans established themselves in Africa, smaller populations branched out to establish footholds in Asia before spreading east, eventually reaching the Americas. At each step, a small group of migrants took a fraction of humanity's genetic diversity with it, creating a series of population bottlenecks.


This should be easy to see in our DNA, but so far it has turned out to be complicated. Different attempts using distinct populations and methods have come to mixed conclusions about whether a clear signal is there.


Now, a large international team of researchers has gone and sequenced genomes from multiple populations along humanity's route out of Africa, and they found a signature of these bottlenecks both in terms of genetic variation and in terms of potentially harmful mutations.


Humans have been present in Africa for much longer than anywhere else, and that shows up in our genetics. African populations tend to have the most genetic variability based on a number of measures. When some of that population left Africa about 50,000 years ago, they took only a part of that diversity with them into Asia. Some of that diversity went left into Europe, and a different subset took a right and spread through Asia, eventually reaching the Pacific, Australia, and the Americas.


The resulting populations haven't been around long enough for many new genetic changes to spread widely within them. And until recently, there hasn't been widespread mixing among the populations (with the exception of some regions like North Africa and the Mideast). So theoretically the genetic signature of the bottlenecks should be there.


Most attempts at trying to spot it, however, have focused on comparing European and African populations. Depending on the precise population used and the methods employed, they come up with different answers—typically, these studies have simply compared African-Americans to European-Americans, since these were the easiest populations to obtain DNA from.


The new study involves obtaining draft genomes from multiple populations along the migratory route out of Africa. These include some of the oldest human populations in Africa (the San and Mbuti), along with a North-African population, the Parthians of Central Asia, and natives of Cambodia, eastern Siberia, and Central America (Cambodians, Yakut, and Maya, respectively). Comparisons between these genomes were then analyzed according to their migratory distance from Africa.


Many of the variations in the human genome have no effect on fitness; they're not in or anywhere near genes, and changes there don't seem to affect anything. In some human populations, these locations can hold any of the four DNA bases. But as you move farther from Africa, more of these are likely to hold just one of them—apparently, the remaining diversity was lost in a bottleneck.


Things were even more dramatic when considering changes that occur within genes. These could be analyzed in light of a change's severity. Some mutations are likely to truncate the protein they encode, causing a severe effect; others will change its sequence of amino acids, causing a less severe problem.


Severe mutations were significantly more common in populations that were farther from our African origin, with the Mayan population having the most. In some cases, the populations had nothing but the harmful variant. Either natural selection simply hasn't had time to get rid of them, or those populations ended up starting out with nothing but the mutation.

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Present-day Amazonians share an unexpected genetic link with Asian islanders, hinting at unknown migration track

Present-day Amazonians share an unexpected genetic link with Asian islanders, hinting at unknown migration track | Amazing Science | Scoop.it

A mysterious group of humans crossed the Bering land bridge from Siberia into the Americas thousands of years ago, genetic analysis reveals. Modern-day signatures of this ‘unknown population’ survive in people who live deep in the Brazilian Amazon, but the two research teams who have made the discovery have different ideas about when and how these migrants reached the Americas12.


"This is an unexpected finding," says Jennifer Raff, an anthropological geneticist at the University of Texas at Austin who was not involved in either study. "It’s honestly one of the most exciting results we’ve seen in a while."


North and South America were the last continents that humans settled. Previous studies of DNA from modern and ancient Native Americans suggest that the trek was made at least 15,000 years ago (although the timing is not clear-cut) by a single group dubbed the ‘First Americans’, who crossed the Bering land bridge linking Asia and North America.


“The simplest hypothesis would be that a single population penetrated the ice sheets and gave rise to most of the Americans,” says David Reich, a population geneticist at Harvard Medical School in Boston, Massachusetts. In 2012, his team found evidence for a single founding migration in the genomes from members of 52 Native American groups3.


So Reich was flabbergasted when a colleague called Pontus Skoglund mentioned during a conference last year that he had found signs of a second ancient migration to the Americas lurking in the DNA of contemporary Native Amazonians. Reich wasted no time in verifying the discovery. “During the session afterward, he passed his laptop over the crowd, and he had corroborated the results,” says Skoglund, who is now a researcher in Reich’s lab.


Skoglund’s discovery — which is published online on 21 July in Nature2 — was that members of two Amazonian groups, the Suruí and the Karitiana, are more closely related to Papua New Guineans and Aboriginal Australians than other Native Americans are to these Australasian  groups. The team confirmed the finding with several statistical methods used to untangle genetic ancestry, as well as additional genomes from Amazonians and Papuans. “We spent a lot of time being sceptical and incredulous about the finding and trying to make it go away, but it just got stronger,” says Reich.


Their explanation is that distant ancestors of Australasians also crossed the Bering land bridge, only to be replaced by the First Americans in most of North and South America. Other genetic evidence suggests that modern-day Australasians descend from humans who once lived more widely across Asia. “We think this is an ancestry that no longer exists in Asia, which crossed Beringia at some point, but has been overwritten by later events,” Reich says. The team calls this ghost population “Population Y”, after the word for ancestor, Ypykuéra, in the languages spoken by the Suruí and Karitiana. They contend that Population Y reached the Americas either before or around the same time as the First Americans, more than 15,000 years ago.

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Oldest-known stone tools pre-date Homo

Oldest-known stone tools pre-date Homo | Amazing Science | Scoop.it

Scientists working in the desert badlands of northwestern Kenya have found stone tools dating back 3.3 million years, long before the advent of modern humans, and by far the oldest such artifacts yet discovered. The tools, whose makers may or may not have been some sort of human ancestor, push the known date of such tools back by 700,000 years; they also may challenge the notion that our own most direct ancestors were the first to bang two rocks together to create a new technology.


Hominins are a group of species that includes modern humansHomo sapiens, and our closest evolutionary ancestors. Anthropologists long thought that our relatives in the genus Homo - the line leading directly to Homo sapiens - were the first to craft such stone tools. But researchers have been uncovering tantalizing clues that some other, earlier species of hominin, distant cousins, if you will, might have figured it out.


The researchers do not know who made these oldest of tools. But earlier finds suggest a possible answer: The skull of a 3.3-million-year-old hominin, Kenyanthropus platytops, was found in 1999 about a kilometer from the tool site. A K. platyops tooth and a bone from a skull were discovered a few hundred meters away, and an as-yet unidentified tooth has been found about 100 meters away.


The precise family tree of modern humans is contentious, and so far, no one knows exactly how K. platyops relates to other hominin species. Kenyanthropus predates the earliest known Homo species by a half a million years. This species could have made the tools; or, the toolmaker could have been some other species from the same era, such as Australopithecus afarensis, or an as-yet undiscovered early type of Homo.

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Mummified bodies from 18th century Europe found to have multiple tuberculosis infections

Mummified bodies from 18th century Europe found to have multiple tuberculosis infections | Amazing Science | Scoop.it

Bodies found in a 200 year-old Hungarian crypt have revealed the secrets of how tuberculosis (TB) took hold in 18th century Europe, according to a research team involving UCL scientists.


A new study published in Nature Communications details how samples taken from naturally mummified bodies found in an 18th century crypt in the Dominican church of Vác in Hungary have yielded 14 TB genomes, suggesting that mixed infections were common when TB was at peak prevalence in Europe.


The research team included collaborators from the Universities of Warwick and Birmingham, UCL, the Hebrew University in Jerusalem and the Hungarian Natural History Museum in Budapest. Lead author Professor Mark Pallen, from Warwick Medical School, said the discovery was significant for current and future infection control and diagnosis.


Professor Pallen said: “Microbiological analyses of samples from contemporary TB patients usually report a single strain of TB per patient. By contrast, five of the eight bodies in our study yielded more than one type of TB – remarkably from one individual we obtained evidence of three distinct strains.”


The team used a technique called “metagenomics” to identify TB DNA in the historical specimens—that is direct sequencing of DNA from samples without growing bacteria or deliberately fishing out TB DNA. This approach draws on the remarkable throughput and ease of use of modern DNA sequencing technologies.

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8,000 Years Ago, 17 Women Reproduced for Every One Man

8,000 Years Ago, 17 Women Reproduced for Every One Man | Amazing Science | Scoop.it

Once upon a time, 4,000 to 8,000 years after humanity invented agriculture, something very strange happened to human reproduction. Across the globe, for every 17 women who were reproducing, passing on genes that are still around today—only one man did the same.


"It wasn't like there was a mass death of males. They were there, so what were they doing?" asks Melissa Wilson Sayres, a computational biologist at Arizona State University, and a member of a group of scientists who uncovered this moment in prehistory by analyzing modern genes.


Another member of the research team, a biological anthropologist, hypothesizes that somehow, only a few men accumulated lots of wealth and power, leaving nothing for others. These men could then pass their wealth on to their sons, perpetuating this pattern of elitist reproductive success. Then, as more thousands of years passed, the numbers of men reproducing, compared to women, rose again. "Maybe more and more people started being successful," Wilson Sayres says. In more recent history, as a global average, about four or five women reproduced for every one man.


Physically driven natural selection shaped many human traits. Ethnic Africans and Europeans had to evolve to digest milk, for example, while most ethnic Tibetans have adaptations to deal with the lower oxygen levels at high altitudes. But if Wilson Sayres' team's hypothesis is correct, it would be one of the first instances that scientists have found of culture affecting human evolution.


The team uncovered this dip-and-rise in the male-to-female reproductive ratio by looking at DNA from more than 450 volunteers from seven world regions. Geneticists analyzed two parts of the DNA, Y-chromosome DNA and mitochondrial DNA. These don't make up a large portion of a person's genetics, but they're special because people inherit Y-chromosome DNA exclusively from their male ancestors and mitochondrial DNA exclusively from their female ancestors. By analyzing diversity in these parts, scientists are able to deduce the numbers of female and male ancestors a population has. It's always more female.


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Alexa Earl's curator insight, May 26, 2015 6:45 PM

This story really amazed me because it shows how women play such a huge impact on the world and it also ties well with human geo in general. Women play a huge part in the world and this diagram shows how they are continuing to play such a huge part.

Flo Cuadra Scrofft's curator insight, May 27, 2015 9:52 AM

Insight- Again, it is unbelievable that although women have historically outnumbered men, women don't enjoy the same benefits men do, in agriculture, payment, etc. We should be wiser and take into consideration these trends in order to increase the productivity of the entire world.

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2.8 million-year-old jawbone found in Ethiopia

2.8 million-year-old jawbone found in Ethiopia | Amazing Science | Scoop.it

2.8 million-year-old jawbone may be the oldest human fossil in existence,according to two papers published simultaneously in Science. Researchers now suspect that Homo (the genus that includes modern humans) dates back at least 400,000 years earlier than previously thought.


For decades scientists have been scouring Africa for ancient human remains. Archaeologists think Homo habilis, the first truly “human-like” primate, lived about 2.5 million years ago, and Lucy, the human-ape mashup who is perhaps our most famous ancestor, lived about 3.2 million years ago.


But this particular fossil, found in the Afar region of Ethiopia and temporarily named LD 350-1, appears to be a new type of Homo that falls right between Lucy and Homo habilis. The fossil’s slim molars and proportionate jaw are hallmarks of habilis, for instance, but its primitive chin looks a lot more like Lucy’s. For now, the researchers are calling their discovery “Homo species indeterminate,” as they still aren’t exactly sure what it is.


Most 2.8 million-year-old fossils are too ancient to date by conventional means, so the researchers sampled volcanic ash above and below the jawbone and then used argon40 dating to determine the age of the eruption that formed each sample. The results give us the youngest and oldest dates that the hominin who owned LD 350-1 could have lived—2.5 and 2.8 million years ago, respectively.

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JebaQpt's comment, November 24, 2015 6:33 AM
Today Google Doodle for the Discovery of Lucy https://www.youtube.com/watch?v=vinHUMRF0Pw&list=PLK2ccNIJVPpAlYHL7UaTP5uUs6eux28ZG
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DNA recovered from underwater British site may rewrite history of farming in Europe

DNA recovered from underwater British site may rewrite history of farming in Europe | Amazing Science | Scoop.it

Hunter-gatherers may have brought agricultural products to the British Isles by trading wheat and other grains with early farmers from the European mainland. That’s the intriguing conclusion of a new study of ancient DNA from a now submerged hunter-gatherer camp off the British coast. If true, the find suggests that wheat made its way to the far edge of Western Europe 2000 years before farming was thought to have taken hold in Britain.


The work confronts archaeologists “with the challenge of fitting this into our worldview,” says Dorian Fuller, an archaeobotanist at University College London who was not involved in the work.


For decades, archaeologists had thought that incoming farmers from the Middle East moved into Europe beginning about 10,500 years ago and replaced or transformed hunter-gatherer populations as they moved west, not reaching Britain until about 6000 years ago. But that worldview had already undergone some modifications. Recent discoveries, for example, have shown some incoming farmers coexisted with the hunter-gatherers already living in Europe rather than quickly replacing them. In 2013, researchers reported that, beginning about 6000 years ago, farmers and hunter-gatherers had both buried their dead in the same cave in Germany and continued to do so for 800 years, suggesting that the two groups were in close contact.  More controversially, researchers claimed that about 6500 years ago hunter-gatherers in Germany and Scandinavia may have acquired domesticated pigs from nearby farmers.

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Indo-European languages emerged roughly 6,500 years ago on Russian steppes, new research suggests

Indo-European languages emerged roughly 6,500 years ago on Russian steppes, new research suggests | Amazing Science | Scoop.it

Linguists have long agreed that languages from English to Greek to Hindi, known as 'Indo-European languages', are part of a language family which first emerged from a common ancestor spoken thousands of years ago. Now, a new study gives us more information on when and where it was most likely used. Using data from over 150 languages, linguists at the University of California, Berkeley provide evidence that this ancestor language originated 5,500 - 6,500 years ago, on the Pontic-Caspian steppe stretching from Moldova and Ukraine to Russia and western Kazakhstan.


"Ancestry-constrained phylogenetic analysis supports the Indo-European steppe hypothesis", by Will Chang, Chundra Cathcart, David Hall and Andrew Garrett, will appear in the March issue of the academic journal LanguageThis article is available on the LSA website.


The article provides new support for the "steppe hypothesis" or "Kurgan hypothesis", which proposes that Indo-European languages first spread with cultural developments in animal husbandry around 4500 - 3500 BCE. An alternate theory proposes that they spread much earlier, around 7500 - 6000 BCE, in Anatolia in modern-day Turkey.


Chang et al. examined over 200 sets of words from living and historical Indo-European languages; after determining how quickly these words changed over time through statistical modeling, they concluded that the rate of change indicated that the languages which first used these words began to diverge approximately 6,500 years ago, in accordance with the steppe hypothesis.


This is one of the first quantitatively-based academic papers in support of the steppe hypothesis, and the first to use a model with "ancestry constraints" which more directly incorporate previously discovered relationships between languages. Discussion of prior studies in favor of and against the steppe hypothesis can be found in the paper.

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How Neanderthal DNA Helps Humanity: A Map of Ancient Genes

How Neanderthal DNA Helps Humanity: A Map of Ancient Genes | Amazing Science | Scoop.it

Neanderthals and Denisovans would have been a good source of helpful DNA for our ancestors. They had lived in Europe and Asia for hundreds of thousands of years — enough time to adjust to the cold climate, weak sun and local microbes. “What better way to quickly adapt than to pick up a gene variant from a population that had probably already been there for 300,000 years?” Akey said. Indeed, the Neanderthal and Denisovan genes with the greatest signs of selection in the modern human genome “largely have to do with how humans interact with the environment,” he said.

 

To find these adaptive segments, scientists search the genomes of contemporary humans for regions of archaic DNA that are either more common or longer than expected. Over time, useless pieces of Neanderthal DNA — those that don’t help the carrier — are likely to be lost. And long sections of archaic DNA are likely to be split into smaller segments unless there is selective pressure to keep them intact.

 

In 2014, two groups, one led by Akey and the other by David Reich, a geneticist at Harvard Medical School, independently published genetic maps that charted where in our genomes Neanderthal DNA is most likely to be found. To Akey’s surprise, both maps found that the most common adaptive Neanderthal-derived genes are those linked to skin and hair growth. One of the most striking examples is a gene called BNC2, which is linked to skin pigmentation and freckling in Europeans. Nearly 70 percent of Europeans carry the Neanderthal version.

 

Scientists surmise that BNC2 and other skin genes helped modern humans adapt to northern climates, but it’s not clear exactly how. Skin can have many functions, any one of which might have been helpful. “Maybe skin pigmentation, or wound healing, or pathogen defense, or how much water loss you have in an environment, making you more or less susceptible to dehydration,” Akey said. “So many potential things could be driving this — we don’t know what differences were most important.”

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King Tutankhamun buried with dagger made of space iron from meteorite

King Tutankhamun buried with dagger made of space iron from meteorite | Amazing Science | Scoop.it

King Tutankhamun, the boy king of Egypt, was buried with a dagger made of space from a meteorite, a new study has found.

The weapon, placed on the right thigh of the mummified body, came from iron of meteoric origins, a team of Italian and Egyptians researchers has confirmed. The team used a non-invasive X-ray technique to confirm the composition of the iron without damaging it, according to the study published in the journal of Meteoritics and Planetary Science.

 

"Meteoritic iron is clearly indicated by the presence of a high percentage of nickel," the study's main author Daniela Comelli told Discovery News.

 

Iron meteorites are mostly made of iron and nickel, with small quantities of cobalt, phosphorus, sulfur and carbon.

 

Artefacts produced with iron ore quarrying will show 4 per cent nickel at most, however the dagger found in the tomb was composed of nearly 11 per cent nickel.

 

The cobalt traces found in the iron dagger further confirmed the meteoric origin, Associate Professor Comelli said. "The nickel and cobalt ratio in the dagger blade is consistent with that of iron meteorites that have preserved the primitive chondritic ratio during planetary differentiation in the early solar system," she said.

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Novel collagen fingerprinting identifies a Neanderthal bone among 2,000 fragments

Novel collagen fingerprinting identifies a Neanderthal bone among 2,000 fragments | Amazing Science | Scoop.it

Scientists from the universities of Oxford and Manchester have used a new molecular fingerprinting technique to identify one Neanderthal bone from around 2,000 tiny bone fragments. 

 

All the tiny pieces of bone were recovered from a key archaeological site, Denisova Cave in Russia, with the remaining fragments found to be from animal species like mammoths, woolly rhino, wolf and reindeer. It is the first time that researchers have identified traces of an extinct human from an archaeological site using a technique called 'Zooarchaeology by Mass Spectrometry' or ZooMS.

 

From just a microscopic sample of bone, their analysis revealed the collagen peptide sequences in the bone that mark out one species from another. Their paper, which appears in the journal Scientific Reports, suggests that ZooMS has huge potential to increase our understanding of human evolution, including the amount of interbreeding that went on between our closely related cousins and modern humans.

 

The international research team was led by Professor Thomas Higham and his student Sam Brown of the University of Oxford, with the developer of the ZooMS method, Dr Michael Buckley from the University of Manchester; the Max Planck Institute in Leipzig; Cranfield University; and the Institute of Archaeology and Ethnography, Russia. The sequences of collagen peptides in bone differ in tiny ways between different animal species. The team profiled the sequences using microscopic samples from 2,300 unidentified bone fragments from the site. They then compared the sequences obtained against a reference library of peptides from known animal species.

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What people and their domesticated animals ate 30,000 years ago

What people and their domesticated animals ate 30,000 years ago | Amazing Science | Scoop.it

Biogeologists have shown how Gravettian people shared their food 30,000 years ago. Around 30,000 years ago Predmosti was inhabited by people of the pan-European Gravettian culture, who used the bones of more than 1000 mammoths to build their settlement and to ivory sculptures. Did prehistoric people collect this precious raw material from carcasses -- easy to spot on the big cold steppe -- or were they the direct result of hunting for food?

Předmostí I is an exceptional prehistoric site located near Brno in the Czech Republic. Around 30,000 years ago it was inhabited by people of the pan-European Gravettian culture, who used the bones of more than 1,000 mammoths to build their settlement and to ivory sculptures. Did prehistoric people collect this precious raw material from carcasses -- easy to spot on the big cold steppe -- or were they the direct result of hunting for food? This year-round settlement also yielded a large number of canids remains, some of them with characteristics of Palaeolithic dogs. Were these animals used to help hunt mammoths?

To answer these two questions, Tübingen researcher Hervé Bocherens and his international team carried out an analysis of carbon and nitrogen stable isotopes in human and animal fossil bones from the site. Working with researchers from Brno and Brussels, the researchers were able to test whether the Gravettian people of Předmostí ate mammoth meat and how the "palaeolithic dogs" fit into this subsistence picture.

They found that humans did consume mammoth -- and in large quantities. Other carnivores, such as brown bears, wolves and wolverines, also had access to mammoth meat, indicating the high availability of fresh mammoth carcasses, most likely left behind by human hunters. Surprisingly, the dogs did not show a high level of mammoth consumption, but rather consumed essentially reindeer meat that was not the staple food of their owners. A similar situation is observed in traditional populations from northern regions, who often feed their dogs with the food that they do not like. These results also suggest that these early dogs were restrained, and were probably used as transportation helpers.

These new results provide clear evidence that mammoth was a key component of prehistoric life in Europe 30,000 years ago, and that dogs were already there to help.

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Here's how genetics helped crack the history of human migration

Here's how genetics helped crack the history of human migration | Amazing Science | Scoop.it

Humans evolved in Africa, spread across the world, and then it gets messy. Luckily advances in genetic sequencing have helped us track the complex history of human migration.


Our ability to sequence DNA has increased dramatically since the human genome was first sequenced 15 years ago. In its most basic form, genetic analysis involves comparing DNA from different sets of people, whether between people with or without a particular type of cancer, or individuals from different regions of the world.


The human genome is 3 billion letters long, but as people differ at just one letter in every thousand, on average, we don’t have to look at them all. Instead, we can compare people where we know there are these differences, known as genetic markers. Millions of these markers have been discovered and, together with a genetic sequencing technology that allows us to cheaply look at these markers in lots of people, there has been an explosion in the data available to geneticists.


But while these analyses have shed light on different genetic associations, they have been unable to fully explain the genetic architecture of disease. It is becoming increasingly clear that rare genetic variants with small effects are likely to play a key role in genetic susceptibility to disease. And, because they are rare, finding these variants requires a whole-genome’s worth of sequence.


For that reason, the last ten years has also seen huge innovation in the technology available to read every letter of a genome. Today’s genome sequencing technologies typically work by breaking up DNA into billions of little pieces and then sequencing each of them separately but simultaneously in order to combine them into a full genome.


Via Integrated DNA Technologies, CineversityTV
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Hobbits Were a Separate Species, Ancient Chompers Show

Hobbits Were a Separate Species, Ancient Chompers Show | Amazing Science | Scoop.it

An ancient, 3-foot-tall (0.9 meters) human whose diminutive stature has earned it the nickname "hobbit" has puzzled evolutionary scientists since its little bones were discovered on the Indonesian island of Flores. Some have suggested the individual was a Homo sapiens with some miniaturizing disorder.


Now, teeth from the hobbit suggest it belonged to a unique species rather than a modern human with a growth disorder. The new research also suggests hobbits may share a direct ancestor with modern humans.


Via Kathy Bosiak
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The ability to digest milk may have become common only relatively recently in Europe

The ability to digest milk may have become common only relatively recently in Europe | Amazing Science | Scoop.it

The Bronze Age of Eurasia (around 3000–1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. A group of researchers now investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. They show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. These findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. They could also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought. 

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Complex genetic ancestry of Americans uncovered

Complex genetic ancestry of Americans uncovered | Amazing Science | Scoop.it

By comparing the genes of current-day North and South Americans with African and European populations, an Oxford University study has found the genetic fingerprints of the slave trade and colonization that shaped migrations to the Americas hundreds of years ago.


The study published in Nature Communications found that:

  • While Spaniards provide the majority of European ancestry in continental American Hispanic/Latino populations, the most common European genetic source in African-Americans and Barbadians comes from Great Britain.
  • The Basques, a distinct ethnic group spread across current-day Spain and France, provided a small but distinct genetic contribution to current-day Continental South American populations, including the Maya in Mexico.
  • The Caribbean Islands of Puerto Rico and the Dominican Republic are genetically similar to each other and distinct from the other populations, probably reflecting a different migration pattern between the Caribbean and mainland America.
  • Compared to South Americans, people from Caribbean countries (such as the Barbados) had a larger genetic contribution from Africa.
  • The ancestors of current-day Yoruba people from West Africa (one of the largest African ethnic groups) provided the largest contribution of genes from Africa to all current-day American populations.
  • The proportion of African ancestry varied across the continent, from virtually zero (in the Maya people from Mexico) to 87% in current-day Barbados.
  • South Italy and Sicily also provided a significant European genetic contribution to Colombia and Puerto Rico, in line with the known history of Italian emigrants to the Americas in the late 19th and early 20th century.
  • One of the African-American groups from the USA had French ancestry, in agreement with historical French immigration into the colonial Southern United States.
  • The proportion of genes from European versus African sources varied greatly from individual to individual within recipient populations.


The team, which also included researchers from UCL (University College London) and the Universita' del Sacro Cuore of Rome, analysed more than 4,000 previously collected DNA samples from 64 different populations, covering multiple locations in Europe, Africa and the Americas. Since migration has generally flowed from Africa and Europe to the Americas over the last few hundred years, the team compared the 'donor' African and European populations with 'recipient' American populations to track where the ancestors of current-day North and South Americans came from.


'We found that the genetic profile of Americans is much more complex than previously thought,' said study leader Professor Cristian Capelli from the Department of Zoology. The research team analyzed DNA samples collected from people in Barbados, Columbia, the Dominican Republic, Ecuador, Mexico, Puerto Rico and African-Americans in the USA. They used a technique called haplotype-based analysis to compare the pattern of genes in these 'recipient populations' to 'donor populations' in areas where migrants to America came from.

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World's Oldest Stone Tools Found That Predate Modern Humans By 500,000 Years

World's Oldest Stone Tools Found That Predate Modern Humans By 500,000 Years | Amazing Science | Scoop.it

Scientists working in East Africa say they've unearthed the oldest stone tools ever found. They were apparently made 500,000 years before the human lineage evolved. A team led by Sonia Harmand from Stony Brook University in New York found the tools in Kenya, near Lake Turkana. It's an area that's yielded numerous fossils and tools from early humans. These newly discovered tools have been reliably dated to 3.3 million years ago, according to scientists who've reviewed the research. That's 700,000 years older than the previous record for the oldest stone tools ever found.


That's remarkable because it's well before the human genus, Homo, emerged 2.8 million years ago. So clearly these early humans didn't make these tools. The team presumes they were made by an early ancestor of humans, probably a member of a genus called Australopithecus. The famous ape-like creature known as Lucy was from that genus and first appeared in Africa about four million years ago.


Leading stone tool experts who've seen the tools say they have the markings of a process called "knapping." Knapping a piece of stone produces flakes that can have sharp edges and are useful for working with plants, nuts or meat. These flakes can be distinguished from naturally occurring pieces of rock. Knapping also leaves characteristic marks on the rock from which the flakes are chipped.


Richard Potts, head of the Human Origins Program at the Smithsonian Institution, has examined the tools. He tells NPR they're a "mixed bag," with some quite crude and others a little more sophisticated. Potts says they're not as advanced as most early human-made tools, but "there's no doubt it's purposeful" tool-making. And it's more sophisticated than the kind of tool-making that chimpanzees do, he adds, such as shaping sticks to probe for termites in their underground mounds.

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Neanderthals made jewellery from eagle talons in Europe 80,000 years before Homo sapiens arrived

Neanderthals made jewellery from eagle talons in Europe 80,000 years before Homo sapiens arrived | Amazing Science | Scoop.it
Neanderthals were making jewellery from the talons of the white-tailed eagle – one of the largest birds of prey in Europe – 80,000 years before the first members of our own species Homo sapiens arrived on the continent, scientists have discovered.


A study has revealed that eight claws from at least three different eagles had been made into a necklace or bracelet worn by Neanderthal people when they were the only humans in Europe 150,000 years ago. The scientists said that the discovery shows that Neanderthal man was not the brutish species he is frequently depicted, but someone who was capable of careful planning and an ability to recognise the symbolic beauty of body ornaments.


“Homo sapiens was not so unique in expressions of symbolism. A lot of evidence emerging in the last few years provides new information about the sophistication of Neanderthals, despite all the decades of prehistoric bias and discrimination against them,” said David Frayer, emeritus professor anthropology at the University of Kansas.


“Neanderthals are often thought of to be simple-minded mumbling, bumbling, stumbling fools. But the more we know about them, the more sophisticated they’ve become,” Professor Frayer said.


The eight talons and a foot bone were once attached to one another by a string or thread, the scientists believe. In addition to 21 individual cut marks, the talons have polished surfaces caused by one talon rubbing against another, said Professor Frayer, who was part of the team that identified the jewellery.


“These are the oldest [eagle talons] found and there are eight, all showing signs of wear, polish and/or manipulation, suggesting they were part of a jewellery composition, maybe a necklace, maybe a bracelet,” Professor Frayer said.

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Genome analysis reveals that herders moved en masse from Russia to Central Europe around 4,500 years ago

Genome analysis reveals that herders moved en masse from Russia to Central Europe around 4,500 years ago | Amazing Science | Scoop.it

Analysis of the genomes of 69 ancient Europeans has revealed that herders moved en masse from Russia into Central Europe around 4,500 years ago. These migrants may be responsible for the expansion of Indo-European languages, which make up the majority of spoken tongues in Europe today.


Data from the genomes of 69 ancient individuals suggest that herders moved en masse from the continent's eastern periphery into Central Europe. These migrants may be responsible for the expansion of Indo-European languages, which make up the majority of spoken tongues in Europe today.


An international team has published the research in the journal NatureProf David Reich and colleagues extracted DNA from remains found at archaeological sites around the continent. They used a new DNA-enrichment technique that greatly reduces the amount of sequencing needed to obtain genome-wide data.


Their analyses show that 7,000-8,000 years ago, a closely related group of early farmers moved into Europe from the Near East, confirming the findings of previous studies. The farmers were distinct from the indigenous hunter-gatherers they encountered as they spread around the continent. Eventually, the two groups mixed, so that by 5,000-6,000 years ago, the farmers' genetic signature had become melded with that of the indigenous Europeans.


But previous studies show that a two-way amalgam of farmers and hunters is not sufficient to capture the genetic complexity of modern Europeans. A third ancestral group must have been added to the melting pot more recently.


Prof Reich and colleagues have now identified a likely source area for this later diaspora. The Bronze Age Yamnaya pastoralists of southern Russia are a good fit for the missing third genetic component in Europeans. The team analysed nine genomes from individuals belonging to this nomadic group, which buried their dead in mounds known as kurgans.


The scientists contend that a group similar to the Yamnaya moved into the European heartland after the invention of wheeled vehicles, contributing up to 50% of ancestry in some modern north Europeans. Southern Europeans on the whole appear to have been less affected by the expansion.

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Trail of Tools Reveals Modern Humans' Path Out of Africa

Trail of Tools Reveals Modern Humans' Path Out of Africa | Amazing Science | Scoop.it

Where did our species come from, and how did we get from there to everywhere? A 55,000-year-old partial skull found in Manot Cave in western Galilee in January 2015 suggests that modern humans were in the Levant around the same time as Neanderthals.


Now, a pair of American archaeologists claim to have uncovered the route those early Homo sapiens took on their way to populating the planet. By following the broken trail of stone tools that modern humans left behind like bread crumbs marking their path, researchers propose that our ancestors took a circuitous path through Arabia, pausing there for some 50,000 years when it was a green oasis. Then they journeyed on to the Middle East, where they first encountered Neanderthals.


Stylistic and manufacturing similarities, the archaeologists say, connect the dots between tools made first in the Nile Valley of Egypt, then in the Arabian Peninsula, and, finally, in Israel. Those tools became progressively smaller and more sophisticated, similar to the evolution of mobile phones today.


"Archaeologists have always focused so much on 'out of Africa and into the Middle East' that we've missed an entire chapter of the human expansion in Arabia," says archaeologist Jeffrey Rose of the Ronin Institute, based in New Jersey, co-author of a new report published this month in Quartär.

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