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The mammoth was found on the left bank of Yenisey river, not far from Sopochnaya Karga meterological station. Pictures: Vladimir Pitulko, Alexei Tikhonov

The mammoth was found on the left bank of Yenisey river, not far from Sopochnaya Karga meterological station. Pictures: Vladimir Pitulko, Alexei Tikhonov

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Original article:

siberiantimes.com

By Anna Liesowska

30 May 2016

 

When Science journal earlier this year highlighted an ancient woolly mammoth with suspected spear wounds it provoked media interest around the world. Until now, the pictures of the remarkable prehistoric ‘injuries’ were not widely seen outside academic circles.

Today The Siberian Times is publishing the images which respected Russian scientists believe is clear proof of ancient man’s attacks on a creature preserved in the permafrost.

If true, the implications are enormous. It would mean, firstly, that man was present in the frozen Arctic wastes a full 10,000 years earlier than previously understood.

Yet it would also establish that early Siberians were just 2,895 miles (4,660 kilometres) from what was then a land bridge between modern Russia and Alaska. A long distance, for sure, but far from insurmountable, opening the possibility that Stone Age Siberians colonised the Americas at this early point.

The 15-year-old male mammoth died on the eastern bank of the giant Yenisei River in northern Siberia, and its remains were found by a 11 year old schoolboy in 2012. It is known variously as the Zhenya mammoth, after the boy who found it, and the Sopkarginsky mammoth, deriving from the location where it was found.

Forensic analysis of the remains – which included still-preserved soft tissue – found evidence that the animal, now long extinct, was hunted and killed by early man using primitive weapons and tools made of bone and stone.

Dr Vladimir Pitulko, lead author of the study published in Science, told The Siberian Times: ‘Most likely the hunters threw relatively light spears. It is a usual hunting tactic, in particular in elephant hunts, which is still practiced in Africa.

‘An elephant is bombarded with a large number of light spears. Then, pierced with such ‘needles’ like a hedgehog, the animal starts losing blood. Even a light spear can penetrate quite deep and injure the vital organs.

‘The mobility of the animal is seriously limited, and then it is soon possible to finish it with a strait blow. I think that the same happened to the Sopkarginsky mammoth.’

He said: ‘The most remarkable injury is to the fifth left rib, caused by a slicing blow, inflicted from the front and somewhat from above in a downward direction. Although it was a glancing blow, it was strong enough to go through skin and muscles and damage the bone.

‘A similar but less powerful blow also damaged the second right front rib. Such blows were aimed at internal organs and/or blood vessels.

‘The mammoth was also hit in the left scapula at least three times. Two of these injuries were imparted by a weapon, which went downwards through the skin and muscles, moving from the top and side. These markings indicate injuries evidently left by relatively light throwing spears.

‘A much more powerful blow damaged the spine of the left scapula. It may have been imparted by a thrusting spear, practically straight from the front at the level of the coracoid process. The weapon went through the shoulder skin and muscle, almost completely perforating the spine of the scapula.

‘Taking into account the scapula’s location in the skeleton and the estimated height of this mammoth, the point of impact would be approximately 1500 mm high, in other words, the height of an adult human’s shoulder.’

Another injury – possibly evidence of a mis-directed blow – was spotted on the left jugal bone. The blow was evidently very strong and was suffered by the animal from the left back and from top down, which is only possible if the animal was lying down on the ground.

Dr Pitulko, of the Institute for the History of Material Culture in St Petersburg, believes that it was ‘the final blow’, which was aimed to the base of the trunk.

Modern elephant hunters still use this method ‘to cut major arteries and cause mortal bleeding’. Yet in this case the prehistoric hunters obviously missed and struck the jugal bone instead.

Luckily the spear left the clear trace on the bone, making possible to learn what kind of weapon it was.

The bone was studied with X-ray computed tomography – a CT scan – by Dr Konstantin Kuper, from the Budker Institute of Nuclear Physics in Novosibirsk. He also created a 3D model of the injury in the bone. This led to the conclusion that the tip of the weapon was made of stone and had a thinned symmetric outline – and was relatively sharp.

Paleontologist Dr Alexei Tikhonov, from the Zoological Institute of Russian Academy of Sciences in St Petersburg, who lead the excavations, said: ‘It’s hard to say which blow was the mortal one, at least judging by the traces on the bones.

‘There was quite a strong blow to the scapula, yet I think it was rather the totality of wounds that caused the death. It is interesting that the most of the injuries are on the left side of the animal.

‘I would suppose that the hunters could attack the mammoth which was already lying on the ground. When we examined the skull, we noticed the abnormal development of the upper jaw.

‘We believe that this mammoth got a kind of injury at a very young age, which impacted on its left side. There was no left tusk and I presume that the left side was weak, so it could help the hunters kill the animal.’

The injuries found on the bones also gave clues what did the hunters with the mammoth after they killed it. The right tusk had the traces of human interference on the tip of the tusk.

They did not try and pull the entire tusk off the killed mammal but instead tried to remove ‘long slivers of ivory with sharp edges, which were usable as butchering tools’, said Dr Pitulko.

A butchery mark was also found on the fifth left rib, seen as evidence that the hunters cut meat from the carcass to take it with them. Ancient man also extracted the mammoth tongue, seen as a probable delicacy to these hunters.

Yet the theory that the animal was butchered does not convince all experts.

Dr Robert Park, a professor of anthropology at the University of Waterloo in Canada, wrote in an email to Discover, that the skeleton is not consistent with other evidence from early human hunters.

He wrote: ‘The most convincing evidence that it wasn’t butchered is the fact that the archaeologists recovered the mammoth’s fat hump. Hunter-gatherers in high latitudes need fat both for its food value and as fuel. So the one part of the animal that we would not expect hunters to leave behind is fat.’

But Dr Pitulko countered: ‘Yes, ancient man – and not so ancient, in fact – has used and uses animal fat as fuel and food, nothing to argue about here. Why in this very case they did not use their prey in full is impossible to say.

‘There may be dozens of reasons, for example – they could not – the carcass was lying at the water’s edge, and it was late autumn. Or they did not have time: the carcass fell into the water on thin coastal ice. Or it did not correspond to their plans – they killed the poor animal just to have a meal and replenish the supply of food for a small group.’

They might have killed another animal nearer to their camp, and so abandoned this one. He said ‘a thousand and one reasons’ might explain not purloining the fat.

The expert added: ‘I believe that the main reason for hunting mammoths were their tusks. Mammoth as a source of food wasn’t very necessary although I believe they were useful.

‘People needed tusks because they were living in landscapes free of forests, so called mammoth steppe. In the course of time, a technology to produce spears out of tusks was developed.’

On the significance for the New World, he told Discovery the human role in killing the mammoth ‘is especially important’ because ‘now we know that eastern Siberia up to its Arctic limits was populated starting at roughly 50,000 years ago’.

 

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Arachis ipaensis, left, and Arachis duranensis, right, are the two species of wild peanut that crossed to provide the genetic blueprint for today's modern peanut varieties. (Credit: Merritt Melancon/University of Georgia)

Arachis ipaensis, left, and Arachis duranensis, right, are the two species of wild peanut that crossed to provide the genetic blueprint for today’s modern peanut varieties. (Credit: Merritt Melancon/University of Georgia)

Arachis ipaensis, one of the wild peanut varieties that helped to create the modern peanut, was found in the foothills of the Andes in Bolivia and Argentina in the 1970s. (Credit: Merritt Melancon/University of Georgia)

Arachis ipaensis, one of the wild peanut varieties that helped to create the modern peanut, was found in the foothills of the Andes in Bolivia and Argentina in the 1970s. (Credit: Merritt Melancon/University of Georgia)

 

Original Article:

News.uga.edu

Writer: J. Merritt Melanin, Feb 2016

 

Athens, Ga. – Researchers at the University of Georgia, working with the International Peanut Genome Initiative, have discovered that a wild plant from Bolivia is a “living relic” of the prehistoric origins of the cultivated peanut species.

The peanut that is grown by farmers today is the result of hybridization between two wild species. The hybrid was cultivated by ancient inhabitants of South America and, by selection, was transformed into today’s crop plant.

Comparisons of the DNA sequences of one of the wild species and the cultivated peanut showed that they are almost exactly same; in fact, they are 99.96 percent identical. It’s an unprecedented similarity.

“It’s almost as if we had traveled back in time and sampled the same plant that gave rise to cultivated peanuts from the gardens of these ancient people,” said David Bertioli, an International Peanut Genome Initiative, or IPGI, plant geneticist of the Universidade de Brasília, who is working at UGA.

This discovery forms part of a study that appears in this month’s Nature Genetics journal, published by the UGA-led IPGI. Scott Jackson, director of the UGA Center for Applied Genetic Technologies in the College of Agricultural and Environmental Sciences, serves as chair of the IPGI. Bertioli is lead author on the paper.

Because its ancestors were two different species, today’s peanut carries two separate genomes, designated “A” and “B” subgenomes. Their high similarity means they are very difficult to map out separately when sequencing the cultivated peanut genome. So, as a first step, researchers built their models using the two wild, ancestral peanut species collected by botanists in the wooded foothills of the Andes in Bolivia and Argentina decades ago.

The genome of one of them, Arachis duranensis, is about as similar to the A subgenome as could be expected. However, what really caught their attention was that the genome of the other species, A. ipaensis, was found to be virtually identical to the B subgenome.

Soon after its collection in 1971, the botanists who collected A. ipaensis realized that it was peculiar. The population of A. ipaensis was very small and isolated, and its closest relatives grew hundreds of miles to the north. They questioned how it arrived in the location where they found it growing.

Prompted by the extraordinary DNA identity, the scientists used information from decades-old botanical collections, knowledge of the seasonal movements of ancient hunter-gatherer-farmers and molecular DNA clock calculations to work out that the plants’ seeds had almost certainly been transported by humans about 10,000 years ago.

“Everything fit,” Bertioli said. “It’s the only place where A and B genome species have ever been found growing close together. The region is right next to the region where, even today, the most primitive types of cultivated peanut are grown, and the date is right in the time frame that plant domestication was happening in South America.”

The movement of the B genome species into the range of the A genome species meant that the hybridization could happen, probably courtesy of a native bee, and the cultivated peanut species was formed. The rest is history, Bertioli said.

The new peanut genome sequences were released in 2014 to researchers and plant breeders around the globe. Their use is advancing the breeding of more productive and more resilient peanut varieties. The paper in Nature Genetics represents the first official publication of the IPGI.

The effort to sequence the peanut genome took several years. While peanuts have been successfully bred for intensive cultivation, relatively little was known about the legume’s genetic structure because of its complexity, according to Peggy Ozias-Akins, a senior author on the paper and director of the UGA Institute of Plant Breeding, Genetics and Genomics. The sequences provide researchers access to 96 percent of all peanut genes and provide the DNA map needed to more quickly identify and genetically tag genes that confer desirable traits, such as drought- and disease-resistance.

A consortium of peanut growers, peanut shellers, brokers and food manufacturing groups provided $6 million in funding for the genome sequencing effort through The Peanut Foundation.

Victor Nwosu, program manager for Mars Chocolate and chairman of the board of directors of The Peanut Foundation, is enthusiastic about the advances these discoveries will facilitate.

“The peanut genome project will lead to reduction in production costs through development of disease-resistant varieties and improved yield for farmers, speed of selection and release of new varieties for breeders and potential for improvement of nutritional value of peanuts for consumers,” Nwosu said. “We are beginning to see these benefits already.”

The genome sequence assemblies and additional information are available at http://peanutbase.org/.

The International Peanut Genome Initiative brings together scientists from the U.S., China, Brazil, India, Australia, Japan and Israel to delineate peanut genome sequences, characterize the genetic and phenotypic variation in cultivated and wild peanuts and develop genomic tools for peanut breeding. The initial sequencing was carried out in Shenzhen, China, by the BGI, known previously as the Beijing Genomics Institute.

Assembly was done at the BGI, the U.S. Department of Agriculture Agricultural Research Service in Ames, Iowa, and the University of California, Davis. The project was funded by the peanut industry through The Peanut Foundation and by Mars Inc. and three Chinese academies: the Henan Academy of Agricultural Sciences, Chinese Academy of Agricultural Sciences and Shandong Academy of Agricultural Sciences.

A complete list of the institutions involved with the project and the other funding sources is available at http://peanutbioscience.com/.

The study, “The genome sequences of Arachis duranensis and Arachis ipaensis, the diploid ancestors of cultivated peanut,” will be available online at http://dx.doi.org/10.1038/ng.3517.

 

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The fossilized skull of Australopithecus sediba specimen MH1 and a finite element model of its cranium depicting strains experienced during a simulated bite on its premolars. “Warm” colors indicate regions of high strain, “cool” colors indicate regions of low strain. Credit: WUSTL GRAPHIC: Image of MH1 by Brett Eloff provided courtesy of Lee Berger and the University of the Witwatersrand.

Original Article:

popular-archaeology.com

Feb 8, 2016

Research published in 2012 garnered international attention by suggesting that Australopithecus sediba (A. sediba), a possible early human ancestor species discovered in South Africa by anthropologist Lee Berger, had lived on a diverse woodland diet including hard foods mixed in with tree bark, fruit, leaves and other plant products.

But new research by an international team of researchers now shows that A. sediba didn’t have the jaw and tooth structure necessary to exist on a steady diet of hard foods.

“Most australopiths had amazing adaptations in their jaws, teeth and faces that allowed them to process foods that were difficult to chew or crack open. Among other things, they were able to efficiently bite down on foods with very high forces,” said team leader David Strait, PhD, professor of anthropology in Arts & Sciences at Washington University in St. Louis.

“Australopithecus sediba is thought by some researchers to lie near the ancestry of Homo, the group to which our species belongs,” said Justin Ledogar, PhD, Strait’s former graduate student and now a researcher at the University of New England in Australia. “Now we find that A. sediba had an important limitation on its ability to bite powerfully; if it had bitten as hard as possible on its molar teeth using the full force of its chewing muscles, it would have dislocated its jaw.”

The study, published Feb. 8 in the journal Nature Communications, describes biomechanical testing of a computer-based model of an A. sediba skull. The model is based on the fossil skull recovered in 2008 from the Malapa fossil site by Berger and his team. Malapa is a cave near Johannesburg, South Africa. The biomechanical methods used in the study are similar to those used by engineers to test whether or not planes, cars, machine parts or other mechanical devices are strong enough to avoid breaking during use.

A. sediba, a diminutive pre-human species that lived about two million years ago in southern Africa, has been heralded as a possible ancestor or close relative of Homo. Australopiths appear in the fossil record about four million years ago, and although they have some human traits like the ability to walk upright on two legs, most of them lack other characteristically human features like a large brain, flat faces with small jaws and teeth, and advanced tool-use.

Humans in the genus Homo are almost certainly descended from an australopith ancestor, and A. sediba is a candidate to be either that ancestor or something similar to it.

Some of the researchers who described A. sediba are also authors on the biomechanical study, including Lee Berger, PhD, and Kristian Carlson, PhD, of the University of the Witwatersrand, and Darryl de Ruiter, PhD, of Texas A&M University. Amanda Smith, PhD, a postdoctoral fellow in physical anthropology at Washington University, also participated in the research.

The new study does not directly address whether Australopithecus sediba is indeed a close evolutionary relative of early Homo, but it does provide further evidence that dietary changes were shaping the evolutionary paths of early humans.

“Humans also have this limitation on biting forcefully and we suspect that early Homo had it as well, yet the other australopiths that we have examined are not nearly as limited in this regard,” Ledogar said. “This means that whereas some australopith populations were evolving adaptations to maximize their ability to bite powerfully, others (including A. sediba) were evolving in the opposite direction.”

“Some of these ultimately gave rise to Homo,” Strait said. “Thus, a key to understanding the origin of our genus is to realize that ecological factors must have disrupted the feeding behaviors and diets of australopiths. Diet is likely to have played a key role in the origin of Homo.”

Strait, a paleoanthropologist who has written about the ecological adaptations and evolutionary relationships of early humans, as well as the origin and evolution of bipedalism, said this study offers a good example of how the tools of engineering can be used to answer evolutionary questions. In this case, they help us to better understand what the facial skeleton can tell us about the diet and lifestyles of humans and other primates.

“Our study provides a really nice demonstration of the difference between reconstructing the behaviors of extinct animals and understanding their adaptations.” Strait said. “Examination of the microscopic damage on the surfaces of the teeth of A. sediba has led to the conclusion that the two individuals known from this species must have eaten hard foods shortly before they died. This gives us information about their feeding behavior. Yet, an ability to bite powerfully is needed in order to eat hard foods like nuts or seeds. This tells us that even though A. sediba may have been able to eat some hard foods, it is very unlikely to have been adapted to eat hard foods.”

The bottom line, Strait said, is that the consumption of hard foods is very unlikely to have led natural selection to favor the evolution of a feeding system that was limited in its ability to bite powerfully. This means that the foods that were important to the survival of A. sediba probably could have been eaten relatively easily without high forces.

Source: Subject press release of the University of the Witwatersrand, Johannesburg, South Africa and Washington University in St. Louis, Missouri.

 

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CAPTION An illustration of a giant flightless bird known as Genyornis newtoni, surprised on her nest by a 1 ton, predatory lizard named Megalania prisca in Australia roughly 50,000 thousand years ago. CREDIT Illustration by Peter Trusler, Monash University

CAPTION
An illustration of a giant flightless bird known as Genyornis newtoni, surprised on her nest by a 1 ton, predatory lizard named Megalania prisca in Australia roughly 50,000 thousand years ago.
CREDIT
Illustration by Peter Trusler, Monash University

 

Original Article:

eurekalert.org

January, 2016

Ancient extinction of giant Australian bird points to humans

The first direct evidence that humans played a substantial role in the extinction of the huge, wondrous beasts inhabiting Australia some 50,000 years ago — in this case a 500-pound bird — has been discovered by a University of Colorado Boulder-led team.

The flightless bird, known as Genyornis newtoni, was nearly 7 feet tall and appears to have lived in much of Australia prior to the establishment of humans on the continent 50,000 years ago, said CU-Boulder Professor Gifford Miller. The evidence consists of diagnostic burn patterns on Genyornis eggshell fragments that indicate humans were collecting and cooking its eggs, thereby reducing the birds’ reproductive success.

“We consider this the first and only secure evidence that humans were directly preying on now-extinct Australian megafauna,” said Miller, associate director of CU-Boulder’s Institute of Arctic and Alpine Research. “We have documented these characteristically burned Genyornis eggshells at more than 200 sites across the continent.”

A paper on the subject appears online Jan. 29, in Nature Communications.

In analyzing unburned Genyornis eggshells from more than 2,000 localities across Australia, primarily from sand dunes where the ancient birds nested, several dating methods helped researchers determine that none were younger than about 45,000 years old. Burned eggshell fragments from more than 200 of those sites, some only partially blackened, suggest pieces were exposed to a wide range of temperatures, said Miller, a professor in CU-Boulder’s Department of Geological Sciences.

Optically stimulated luminescence dating, a method used to determine when quartz grains enclosing the eggshells were last exposed to sunlight, limits the time range of burned Genyornis eggshell to between 54,000 and 44,000 years ago. Radiocarbon dating indicated the burnt eggshell was no younger than about 47,000 years old.

The blackened fragments were likely burned in transient, human fires — presumably to cook the eggs — rather than in wildfires, he said.

Amino acids — the building blocks of proteins -decompose in a predictable fashion inside eggshells over time. In eggshell fragments burned at one end but not the other, there is a tell-tale “gradient” from total amino acid decomposition to minimal amino acid decomposition, he said. Such a gradient could only be produced by a localized heat source, likely an ember, and not from the sustained high heat produced regularly by wildfires on the continent both in the distant past and today.

Miller also said the researchers found many of the burnt Genyornis eggshell fragments in tight clusters less than 10 feet in diameter, with no other eggshell fragments nearby. Some individual fragments from the same clusters had heat gradient differences of nearly 1,000 degrees Fahrenheit, conditions virtually impossible to reproduce with natural wildfires there, he said.

“We can’t come up with a scenario that a wildfire could produce those tremendous gradients in heat,” Miller said. “We instead argue that the conditions are consistent with early humans harvesting Genyornis eggs, cooking them over fires, and then randomly discarding the eggshell fragments in and around their cooking fires.”

Another line of evidence for early human predation on Genyornis eggs is the presence of ancient, burned eggshells of emus — flightless birds weighing only about 100 pounds and which still exist in Australia today — in the sand dunes. Emu eggshells exhibiting burn patterns similar to Genyornis eggshells first appear on the landscape about 50,000 years ago, signaling they most likely were scorched after humans arrived in Australia, and are found fairly consistently to modern times, Miller said.

The Genyornis eggs are thought to have been roughly the size of a cantaloupe and weighed about 3.5 pounds, Miller said.

Genyornis roamed the Australian outback with an astonishing menagerie of other now-extinct megafauna that included a 1,000-pound kangaroo, a 2-ton wombat, a 25-foot-long-lizard, a 300-pound marsupial lion and a Volkswagen-sized tortoise. More than 85 percent of Australia’s mammals, birds and reptiles weighing over 100 pounds went extinct shortly after the arrival of the first humans.

The demise of the ancient megafauna in Australia (and on other continents, including North America) has been hotly debated for more than a century, swaying between human predation, climate change and a combination of both, said Miller. While some still hold fast to the climate change scenario — specifically the continental drying in Australia from about 60,000 to 40,000 years ago — neither the rate nor magnitude of that change was as severe as earlier climate shifts in Australia during the Pleistocene epoch, which lacked the punch required to knock off the megafauna, said Miller.

Miller and others suspect Australia’s first inhabitants traveled to the northern coast of the continent on rafts launched from Indonesian islands several hundred miles away. “We will never know the exact time window humans arrived on the continent,” he said. “But there is reliable evidence they were widely dispersed across the continent before 47,000 years ago.”

Evidence of Australia megafauna hunting is very difficult to find, in part because the megafauna there are so much older than New World megafauna and in part because fossil bones are easily destroyed by the chemistry of Australian soils. said Miller.

“In the Americas, early human predation on the giant animals in clear — stone spear heads are found embedded in mammoth bones, for example,” said Miller. “The lack of clear evidence regarding human predation on the Australia megafauna had, until now, been used to suggest no human-megafauna interactions occurred, despite evidence that most of the giant animals still roamed Australia when humans colonized the continent.”

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Co-authors on the new study include Research Professor Scott Lehman, doctoral student Christopher Florian and researcher Stephen DeVogel of CU-Boulder; Research Fellow John Magee of the Australian National University; and researchers from seven other Australian institutions. The study was funded in part by the U.S. National Science Foundation and the Australian Research Council.

 

 

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World's oldest domesticated fava seeds found at Ahihud

World’s oldest domesticated fava seeds found at Ahihud

Original Article:

mfa.gov.il

World’s oldest domesticated fava seeds

A study of seeds exposed in archaeological excavations in recent years at Neolithic sites in the Galilee shows that the inhabitants’ diet at the time consisted mainly of fava beans, as well as lentils, various types of peas and chickpeas.

According to researchers of the Weizmann Institute and Israel Antiquities Authority, ancient man living in the Galilee specialized in cultivating legumes in general and fava beans (ful) in particular. “This is an important discovery, enabling a deeper understanding of the agricultural revolution in the southern Near East.”

A joint study by researchers of the Weizmann Institute and the Israel Antiquities Authority, which examined fava seeds exposed in archaeological excavations in recent years at Neolithic sites in the Galilee, sheds light on the nutritional habits of the people that lived in the area 10,000 years ago. Seeds found at the prehistoric sites show that the inhabitants’ diet at the time consisted mainly of fava beans, as well as lentils, various types of peas and chickpeas.

The excavation site at Ahihud Copyright: Yaron Bibas, courtesy Israel Antiquities Authority

The excavation site at Ahihud
Copyright: Yaron Bibas, courtesy Israel Antiquities Authority

The study was conducted by archaeobotanist Valentina Caracuta, of the Weizmann Institute, together with Dr. Elisabetta Boaretto and Dr. Lior Regev, and in cooperation with archaeologists Dr. Kobi Vardi, Dr. Yitzhak Paz, Dr. Hamoudi Khalaily, Dr. Ianir Milevski and Dr. Omri Barzilai of the Israel Antiquities Authority.

The multitude of fava seeds found at the Neolithic sites excavated in the Galilee during the past few years indicates the preference placed on growing fava beans. The dating of the seeds, which was done at the Kimmel Center in the Weizmann Institute, indicated a range of dates between 9,890-10,160 YBP. These well-preserved seeds were found in excavations, inside storage pits (granaries) after they had been husked. The seeds’ dimensions are a uniform size-a datum showing they were methodically cultivated, and were harvested at the same period of time, when the legumes had ripened. According to the researchers, keeping the seeds in storage pits is also reflective of long-term agricultural planning, whereby the stored seeds were intended not only for food, but also to ensure future crops in the coming years.

The researchers added, “The identification of the places where plant species that are today an integral part of our diet were first domesticated is of great significance to research. Despite the importance of cereals in nutrition that continues to this day, it seems that in the region we examined (west of the Jordan River), it was the legumes, full of flavor and protein, which were actually the first species to be domesticated. A phenomenon known as the agricultural revolution took place throughout the region at this time: different species of animals and plants were domesticated across the Levant, and it is now clear that the area that is today the Galilee was the main producer of legumes in prehistoric times. This is a process that lasted thousands of years, during which certain characteristics of wild species changed, and domesticated plant species were created. To this day, most of the chickpeas grown in the country are cultivated in the Galilee region.”

According to the archaeologists, the accurate dating of the fava seeds, utilizing advanced techniques, led to the conclusion that they found the world’s oldest domesticated fava seeds, dating to 10,125-10,200 YBP.

 

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The size of the human brain had a great deal to do with the food choices of our ancestors. Credit: Shutterstock

The size of the human brain had a great deal to do with the food choices of our ancestors. Credit: Shutterstock

Original Article:

Phys.org

August 31, 2015 by Norman Owen-Smith, The Conversation

 

Much attention is being given to what people ate in the distant past as a guide to what we should eat today. Advocates of the claimed palaeodiet recommend that we should avoid carbohydrates and load our plates with red meat and fat. Its critics, on the other hand, argue that these are the same ingredients that would set us up for heart attacks. Moreover, these animal-derived foods require more space to produce on our crowded planet filled with starving humans.

A factual foundation for the debate is provided by a review of the eating patterns of early humans and how we adapted to digest starches softened by cooking. The researchers contend that it was digestible starches that provided extra energy needed to fuel the energy needs of bigger brains, rather than extra protein from meat to grow these brains.

But the most striking thing about human diets is just how variable they have been and the adaptations that have taken place. Furthermore, the American evolutionary biologist Marlene Zuk in her book Paleofantasy contends that these dietary adaptations are not fixed on what our ancestors ate in caves at some time in the past.

So are our energy, or protein, needs much different from other mammals of similar size? Brains demand a lot of energy but so does the liver and the digestive tract. The extra nutrition that we need for brain work may be counterbalanced, at least partially, by a lesser need for:

a long gut to process poor quality foods, or
a large liver to handle nasty chemicals in these plant parts.
Once built, a large brain does not require extra sources of protein to maintain its activities.

My studies on the dietary requirements of savanna-inhabiting herbivores highlight how these animals must cope with the dry season when most herbage is brown and indigestible even with the aid of microbial symbionts in the gut.

But carnivores do not have this problem because the dry season is when weakened herbivores are most readily killed, especially when they concentrate around scarce waterholes.

The role of carbs among early humans
Meat has long been part of human diets, along with carbohydrates provided by fruits, tubers and grains. We can get by without it, obtaining protein from milk or, with some planning, from legumes.

The early humans that consumed most meat were the Neanderthals, who lived in Europe many thousand years ago, but were not our ancestors. Meat formed the crucial lean-season food for the Neanderthal people during successive winters when plants were seasonally buried under deep snow, but later also for the modern humans who spread through Eurasia and displaced them around 40 000 years ago.

Unlike tropical Africa, meat could be stored during the freezing winters of the far north to provide a reliable food source, especially in the form of large carcasses of elephant-like proboscideans.

This led to a wave of large mammal extinctions as humans spread rapidly into Australia and entered the Americas towards the end of the last Ice Age. By that time hunting technology had been honed and meat routinely supplemented plant food, but the latter remained the dietary staple for African hunter-gatherers like the Bushmen or San people into modern times.

The food journey within evolution

Coping with the intensifying dry season in the expanding African savanna was a critical issue for human ancestors during the evolutionary transition from ape-men to the first humans between three and two million years ago. How did our ape-men ancestors gather sufficient to eat during this time of the year when nutritious fruits and leaves were scarce?

This was when meat, or at least the marrow left within bones, could have become a nutritional fallback, probably acquired by scavenging from animal carcasses not completely consumed by big fierce carnivores, along with underground storage organs of plants.

Obtaining this meat required more walking and hence longer limbs, hands freed to carry, security in numbers and stone weapons to throw at threatening carnivore fangs, but not much expansion in cranial capacity. These were features of the early Australopithicines.

At this early time, another branch of ape-men, placed in the genus Paranthropus, took a different adaptive route. They developed huge jaws to chew on tough plant foods extracted from underground storage organs to get them through the dry season.

The last representative of this genus faded out nearly a million years ago when this strategy eventually became unviable. About that time the lineage leading to early humans discovered cooking, or at least how to use it effectively to make starches stored by plants more readily digestible, according to the article in The Quarterly Review of Biology.

Adding this reliably found source of energy to the proteins acquired more opportunistically by hunting animals or gathering shellfish provided the means to survive through seasonal bottlenecks in food availability and build even bigger brains and the adaptations that followed.

A supporting adaptation was to store more body fat to get through the lean periods, especially among women supporting dependent offspring. This works against us now that foods supplying carbohydrates are plentiful.

The modern day dilemma

The problems we currently face are that we retain a craving for sugar, which was scarce the past, while most of the starchy carbohydrates we eat are highly refined. This means losing out on the other nutrients in plant parts like minerals and vitamins, and most basically fibre.

A meat-based diet could have a role to play for people who have a propensity to store fat by filling the gut for longer and alleviating desires to snack on sweets between meals. More important generally is the need to exercise so that we are hungry enough to consume sufficient food to provide the scarce micronutrients that we also require for healthy bodies.

The best advice is to eat lots of things: meat if you can afford it and justify its planetary costs to produce, but also all kinds of good food, as least refined and processed as you can obtain (apart from wines).

Explore further: Hunger for meat pushing food security to the edge

This story is published courtesy of The Conversation (under Creative Commons-Attribution/No derivatives).

 

 

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Wild Emmer

Wild Emmer

 

The importance of dietary carbohydrate in human evolution

Original Article:

PUBLIC RELEASE: 06-AUG-2015
UNIVERSITY OF CHICAGO PRESS JOURNALS

press.uchicago.edu

 

Understanding how and why we evolved such large brains is one of the most puzzling issues in the study of human evolution. It is widely accepted that brain size increase is partly linked to changes in diet over the last 3 million years, and increases in meat consumption and the development of cooking have received particular attention from the scientific community. In a new study published in The Quarterly Review of Biology, Dr. Karen Hardy and her team bring together archaeological, anthropological, genetic, physiological and anatomical data to argue that carbohydrate consumption, particularly in the form of starch, was critical for the accelerated expansion of the human brain over the last million years, and coevolved both with copy number variation of the salivary amylase genes and controlled fire use for cooking.

With global increase in obesity and diet-related metabolic diseases, interest has intensified in ancestral or ‘Palaeolithic’ diets, not least because – to a first order of approximation – human physiology should be optimized for the nutritional profiles we have experienced during our evolution. Up until now, there has been a heavy focus on the role of animal protein and cooking in the development of the human brain over the last 2 million years, and the importance of carbohydrate, particular in form of starch-rich plant foods, has been largely overlooked.

Hardy’s team highlights the following observations to build a case for dietary carbohydrate being essential for the evolution of modern big-brained humans:

(1) The human brain uses up to 25% of the body’s energy budget and up to 60% of blood glucose. While synthesis of glucose from other sources is possible, it is not the most efficient way, and these high glucose demands are unlikely to have been met on a low carbohydrate diet;

(2) Human pregnancy and lactation place additional demands on the body’s glucose budget and low maternal blood glucose levels compromise the health of both the mother and her offspring;

(3) Starches would have been readily available to ancestral human populations in the form of tubers, as well as in seeds and some fruits and nuts;

(4) While raw starches are often only poorly digested in humans, when cooked they lose their crystalline structure and become far more easily digested;

(5) Salivary amylase genes are usually present in many copies (average ~6) in humans, but in only 2 copies in other primates. This increases the amount of salivary amylase produced and so increases the ability to digest starch. The exact date when salivary amylase genes multiplied remains uncertain, but genetic evidence suggests it was at some point in the last 1 million years.

Hardy proposes that after cooking became widespread, the co-evolution of cooking and higher copy number of the salivary amylase (and possibly pancreatic amylase) genes increased the availability of pre-formed dietary glucose to the brain and fetus, which in turn, permitted the acceleration in brain size increase which occurred from around 800,000 years ago onwards.

Eating meat may have kick-started the evolution of bigger brains, but cooked starchy foods together with more salivary amylase genes made us smarter still.

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Karen Hardy, Jennie Brand Miller, Katherine D. Brown, Mark G. Thomas, and Les Copeland. “The Importance of Dietary Carbohydrate in Human Evolution.” The Quarterly Review of Biology: September 2015.

For further information contact:
Karen Hardy for the overall context of the study +44 780 976 6164, khardy@icrea.cat or karhardy2@googlemail.com
Mark Thomas for questions related to genetics, +44 020 7679 2286, m.thomas@ucl.ac.uk
Jennie Brand Miller for questions related to nutrition and pregnancy, +61 2 9351 3759, jennie.brandmiller@sydney.edu.au
Les Copeland for questions related to starchy foods and carbohydrates, +61 2 8627 1017 les.copeland@sydney.edu.au

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