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Steak..before and after

 

Original article:

By Laurel Hamers

Sciencenews.org

 

WASHINGTON — Kimberly Foecke has a great relationship with her local butcher.

Though she buys loads of meat, Foecke is not a chef or the owner of a small zoo. She’s a paleobiologist who studies what Neandertals ate. And that involves, in her words, “experimental putrefaction, which is a fancy way of saying, I rot meat, all day, every day.”

Scientists know Neandertals ate a lot of meat. Fossilized bones from the hominids tend to have high levels of a heavier form of nitrogen, nitrogen-15, compared with the lighter form, nitrogen-14. Nitrogen-15 is least abundant in plants, and becomes more concentrated further up the food chain because it’s harder to break down than nitrogen-14.

But exactly how much meat these hominids ate — and what else was in their diet — is somewhat controversial. Evidence such as tooth scrapings suggests that Neandertals also ate a variety of plants. But the nitrogen-15 measurements point to “an unreasonably huge amount of meat” in the diet, says Foecke, a researcher at George Washington University in Washington, D.C. Those levels tend to be even higher than what’s seen in top carnivores like hyenas, which nosh almost entirely on meat.

Foecke thinks those high nitrogen-15 ratios may be explained not just by how much meat Neandertals ate, but also how they got it and prepared it. Perhaps whether meat was eaten fresh or rotten, raw or cooked, could influence the nitrogen-15 signal. That’s why she’s measuring nitrogen in cuts of beef, trying to pin down the biochemical changes that the meat undergoes as it rots.

Grocery store steaks wouldn’t cut it for this experiment. Instead, Foecke calls her butcher in Maryland, who makes sure she receives meat that is fresh and from animals raised as close to Pleistocene-style as is possible in 2018 — after all, no hormones or antibiotics were fed to animals hunted 200,000 years ago. She needs animals raised on organic diets she can sample.

Foecke leaves the steaks to rot for 16 days in a mesh-covered box in her family’s backyard, or sometimes in a greenhouse, and samples nitrogen values daily. She plans future sampling for longer periods.

Her preliminary results suggest that nitrogen-15 ratios do fluctuate as meat rots. In the first week, levels increase. The meat is moist, and there’s lots of microbial activity that breaks down the lighter nitrogen-14 faster than the nitrogen-15, Foecke reported December 14 at the American Geophysical Union meeting. It smells “pretty terrible,” she says — though over time, the stench diminishes as the meat blackens and takes on a more jerkylike consistency.

Foecke’s research so far suggests that eating rotting meat could at least partly explain the high nitrogen-15 signatures in Neandertal fossils. And it makes sense that Neandertals weren’t feasting on fresh grub, particularly when they killed large animals. A carcass from a large animal might last days. Foecke is also measuring what happens biochemically as she cooks or smokes meat — food prep steps that Neandertals might have taken that could also affect nitrogen-15.

 

 

 

 

 

 

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Original article:

Eurekalert.org

Researchers find cacao originated 1,500 years earlier than previously thought

University of British Columbia

As Halloween revelers prepare to feast on chocolate, a new study from an international team of researchers, including the University of British Columbia, is pushing back the origins of the delicious sweet treat.

The study, published online today in Nature Ecology & Evolution, suggests that cacao–the plant from which chocolate is made–was domesticated, or grown by people for food, around 1,500 years earlier than previously thought. In addition, the researchers found cacao was originally domesticated in South America, rather than in Central America.

Archaeological evidence of cacao’s use, dating back to 3,900 years ago, previously planted the idea that the cacao tree was first domesticated in Central America. But genetic evidence showing that the highest diversity of the cacao tree and related species is actually found in equatorial South America-where cacao is important to contemporary Indigenous groups-led the UBC team and their colleagues to search for evidence of the plant at an archaeological site in the region.

“This new study shows us that people in the upper reaches of the Amazon basin, extending up into the foothills of the Andes in southeastern Ecuador, were harvesting and consuming cacao that appears to be a close relative of the type of cacao later used in Mexico–and they were doing this 1,500 years earlier,” said Michael Blake, study co-author and professor in the UBC department of anthropology. “They were also doing so using elaborate pottery that pre-dates the pottery found in Central America and Mexico. This suggests that the use of cacao, probably as a drink, was something that caught on and very likely spread northwards by farmers growing cacao in what is now Colombia and eventually Panama and other parts of Central America and southern Mexico.”

Theobroma cacao, known as the cacao tree, was a culturally important crop in pre-Columbian Mesoamerica–a historical region and cultural area in North America that extends from approximately central Mexico through Belize, Guatemala, El Salvador, Honduras, Nicaragua, and northern Costa Rica. Cacao beans were used both as currency and to make the chocolate drinks consumed during feasts and rituals.

For the study, researchers studied ceramic artifacts from Santa Ana-La Florida, in Ecuador, the earliest known site of Mayo-Chinchipe culture, which was occupied from at least 5,450 years ago.

The researchers used three lines of evidence to show that the Mayo-Chinchipe culture used cacao between 5,300 and 2,100 years ago: the presence of starch grains specific to the cacao tree inside ceramic vessels and broken pieces of pottery; residues of theobromine, a bitter alkaloid found in the cacao tree but not its wild relatives; and fragments of ancient DNA with sequences unique to the cacao tree.

The findings suggest that the Mayo-Chinchipe people domesticated the cacao tree at least 1,500 years before the crop was used in Central America. As some of the artifacts from Santa Ana-La Florida have links to the Pacific coast, the researchers suggest that trade of goods, including culturally important plants, could have started cacao’s voyage north.

Sonia Zarrillo, the study’s lead author and adjunct assistant professor at the University of Calgary who carried out some of the research as a sessional instructor at UBC Okanagan’s department of anthropology, said the findings represent a methodological innovation in anthropological research.

“For the first time, three independent lines of archaeological evidence have documented the presence of ancient cacao in the Americas: starch grains, chemical biomarkers, and ancient DNA sequences,” she said. “These three methods combine to definitively identify a plant that is otherwise notoriously difficult to trace in the archaeological record because seeds and other parts quickly degrade in moist and warm tropical environments.”

Discovering the origins of food that we rely on today is important because it helps us understand the complex histories of who we are today, said Blake.

“Today we all rely, to one extent or another, on foods that were created by the Indigenous peoples of the Americas,” said Blake. “And one of the world’s favourites is chocolate.”

 

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Two of my favorite things…Emmer and Haiku, how could I resist.

Minoan Linear A, Linear B, Knossos & Mycenae

Linear A haiku: the sea emmer wheat raindrops:Believe it or not, I was also able to compose a haiku in Linear A, which reads as follows,Linear A haiku tarasa kunisu raniNote that while the word for sea, tarasa, does not appear on any extant Linear A tablets or fragments, it does appear in the pre-Greek substratum, and may very well have existed in the Minoan vernacular. 

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Original Article:

news.com.au

 

Religious dogma in the Middle Ages helped create the modern domestic chicken, research suggests.

Scientists found traits such as reduced aggression, faster egg-laying and an ability to live in close proximity to other birds emerged in chickens in about AD 1000.

Chicken evolution might have been strongly influenced by the impact of Christian beliefs on what people ate.

During the Middle Ages, religious edicts enforced fasting and the exclusion of four-legged animals from menus.

However, the consumption of chickens and eggs was permitted during fasts.

Increasing urbanisation might have helped drive the evolution of modern domesticated chickens, the study, published in the journal Molecular Biology and Evolution, said.

“Ancient DNA allows us to observe how genes have changed in the past, but the problem has always been to get high enough time resolution to link genetic evolution to potential causes,” Oxford University lead researcher Dr Liisa Loog said.

“But with enough data and a novel statistical framework, we now have timings that are precise enough to correlate them with ecological and cultural shifts.”

Chickens were domesticated from Asian jungle fowl around 6000 years ago.

But the new study, which combined DNA data from archaeological chicken bones with statistical modelling, showed some of the most important features of the present-day chicken arose in the high Middle Ages during a time of soaring demand for poultry.

They traced the evolutionary history of more than 70 chickens, looking for changes in the THSR gene that determines levels of aggression.

Natural selection favoured chickens with THSR variants that helped them cope with living close to one another, the study found.

THSR variants also led to faster egg laying and a reduced fear of humans.

A thousand years ago, just 40 per cent of the chickens studied had this gene, which is present in all modern domesticated chickens.

“We tend to think that there were wild animals and then there were domestic animals rather than thinking about the selection pressures on domestic plants and animals that varied through time,” Dr Loog said.

“This study shows how easy it is to turn a trait into something that becomes fixed in an animal in an evolutionary blink of an eye.”

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Participants at the Slav and Viking Festival in Wolin, Poland tend to be sticklers for authenticity. Many adorn their bodies with tattoos, and some adopt a Viking diet, slaughtering and roasting game.  PHOTOGRAPH BY DAVID GUTTENFELDER, NATIONAL GEOGRAPHIC

Participants at the Slav and Viking Festival in Wolin, Poland tend to be sticklers for authenticity. Many adorn their bodies with tattoos, and some adopt a Viking diet, slaughtering and roasting game.
PHOTOGRAPH BY DAVID GUTTENFELDER, NATIONAL GEOGRAPHIC

Nationalgeographic.com

Historical interpreters bring a reconstructed longhouse to life at the Ribe Viking Center in Denmark. Meals were cooked over an open fire on a hearth, and Viking fare included salted herring, barley porridge, and boiled sheep heads.  PHOTOGRAPH BY DAVID GUTTENFELDER, NATIONAL GEOGRAPHIC

Historical interpreters bring a reconstructed longhouse to life at the Ribe Viking Center in Denmark. Meals were cooked over an open fire on a hearth, and Viking fare included salted herring, barley porridge, and boiled sheep heads.
PHOTOGRAPH BY DAVID GUTTENFELDER, NATIONAL GEOGRAPHIC

By Catherine Zuckerman

All that marauding must have left the Vikings famished. It’s easy to envision a group of them around a table, ravenous after a long day of ransacking, devouring giant hunks of meat and hoisting horns-full of ale.
But that wouldn’t quite be fair, or accurate.
As tempting as it is to assume that Viking meals were crude and carnivorous, the truth is that everyday Viking fare included a range of foods that a health-minded modern person would applaud.
Picture, for example, that burly, bearded warrior throwing down his sword to enjoy a tart treat similar to yogurt, or refuel with a tangle of fresh greens.
“The Vikings had a wide range of food and wild herbs available to make tasty and nutritious dishes,” says Diana Bertelsen, who helped research and develop recipes for Denmark’s Ribe Viking Center—a reconstructed Viking settlement where visitors can immerse themselves in just about every aspect of Viking culture, including what and how they ate.
“There are no original recipes from the Viking age available,” says Bertelsen, but “we know for certain what crops and animals were available a thousand years ago. Excavations reveal what the Vikings ate and what they imported, for instance peaches and cinnamon.”

Of course a specific Viking’s diet was heavily influenced by his or her location, says medieval scholar Eleanor Rosamund Barraclough. In cold, dry, coastal Scandinavia, for example, fish such as herring and salmon provided a key source of protein and were typically dried and preserved in salt.
This “stockfish,” as it’s called, “is a bit like beef jerky, only fishy,” says Barraclough. “It would have been a valuable food source on long sea journeys.”
Wealth also played a part in determining one’s diet, says Barraclough. “In Greenland, Vikings ate more seals, particularly on the poorer farms, while on the richer farms they ate more caribou.”
Seasons, too, dictated a Viking’s daily provisions. Depending on the time of year, meals might include a wide variety of berries, turnips, cabbage and other greens—including seaweed—barley-based porridge, and flat bread made from rye. Dishes were typically simple, but “we have no reason to believe that the food was bland and tasteless,” says Bertelsen.
Indeed, archaeological evidence suggests that Viking cooks were fond of flavor-enhancing ingredients like onions, garlic, coriander, and dill.
Vikings also prepared special food to celebrate seasonal events. “Boars were said to be sacrificed during the winter Yule celebration, and solemn oaths taken on their bristles,” says Barraclough.
Dairy would have made a frequent appearance in many a Viking diet. The seafaring warriors were farmers, after all, and skilled at animal husbandry. Cows and sheep did provide meat, but they also gave the Vikings a reliable supply of buttermilk, cheese, butter, and other products.
In Iceland, especially, Vikings enjoyed their dairy, and often ate it in the form of skyr, a fermented, yogurt-like cheese that today is sometimes marketed as a dairy “superfood.” Viking lore mentions the creamy substance, says Barraclough, who recalls a “saga where a man hides from his enemies in a vat of skyr—which comes very specifically up to his nipples.”
Like much about the Vikings, their eating habits remain a source of fascination—and inspiration—for many people. In fact, given the Vikings’ physical strength and surprisingly healthy diet, it makes sense to wonder: Could the “Viking Diet” be the next “Paleo?”

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Fossil analysis suggests Neanderthals ate a diet of 80 percent meat. Photo by OrdinaryJoe/Shutterstock

Fossil analysis suggests Neanderthals ate a diet of 80 percent meat. Photo by OrdinaryJoe/Shutterstock

 

Original Article:

ups.com

By Brooks Hays, March 19, 2016

 

Researchers have long debated the precise diet of early humans, but the latest study is the first to nail down precise percentages.

 

Neanderthals were apparently too busy hunting and scavenging to pay much attention to Michael Pollan’s dietary advice: eat mostly plants.

New isotopic analysis suggests prehistoric humans ate mostly meat. As detailed in a new study published in the journal Quaternary International, the Neanderthal diet consisted of 80 percent meat, 20 percent vegetables.

Researchers in Germany measured isotope concentrations of collagen in Neanderthal fossils and compared them to the isotopic signatures of animal bones found nearby. In doing so, scientists were able to compare and contrast the diets of early humans and their mammalian neighbors, including mammoths, horses, reindeer, bison, hyenas, bears, lions and others.

“Previously, it was assumed that the Neanderthals utilized the same food sources as their animal neighbors,” lead researcher Herve Bocherens, a professor at the University of Tubingen’s Senckenberg Center for Human Evolution and Palaeoenvironment, said in a news release.

“However, our results show that all predators occupy a very specific niche, preferring smaller prey as a rule, such as reindeer, wild horses or steppe bison, while the Neanderthals primarily specialized on the large plant-eaters such as mammoths and woolly rhinoceroses,” Bocherens explained.

All of the Neanderthal and animal bones, dated between 45,000 and 40,000 years old, were collected from two excavation sites in Belgium.

Researchers have long debated the precise diet of early humans, but the latest study is the first to nail down precise percentages.

Bocherens and his colleagues are hopeful their research will shed light on the Neanderthals’ extinction some 40,000 years ago.

“We are accumulating more and more evidence that diet was not a decisive factor in why the Neanderthals had to make room for modern humans,” he said.

 

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Stone Tools

Stone Tools

 

Original Article:

eurekaert.org

Harved University

Processing food before eating likely played key role in human evolution, study finds

 

How much time and effort do you spend chewing?

Although you probably enjoy a few leisurely meals every day, chances are that you spend very little time and muscular effort chewing your food. That kind of easy eating is very unusual. For perspective, our closest relatives, chimpanzees, spend almost half their day chewing, and with much greater force.

When and how did eating become so easy? And what were its consequences?

According to a new Harvard study, our ancestors between 2 and 3 million years ago started to spend far less time and effort chewing by adding meat to their diet and by using stone tools to process their food. The researchers estimate that such a diet would have saved early humans as many as 2.5 million chews per year, and made possible further changes that helped make us human. The study is described in a March 9 paper published in Nature.

One of the biggest puzzles in human evolution is how species such as Homo erectus evolved smaller teeth, smaller faces, and smaller guts, and yet managed to get more energy from food to pay for their bigger brains and bodies before cooking was invented. “What we showed is that…by processing food, especially meat, before eating it, humans not only decrease the effort needed to chew it, but also chew it much more effectively” said Katie Zink, the first author of the study, and a lecturer working in the lab of Daniel Lieberman, the Edwin M. Lerner II Professor of Biological Sciences.

By changing their diets to include just 33 percent meat, and processing their food – slicing meat and pounding vegetables – before eating, Zink and Lieberman found that the muscular effort required per chew and the number of chews required per day was reduced by almost 20 percent. They also found that by simply slicing meat with the sorts of simple tools available more than 2 million years ago, humans were able to swallow smaller, more easily digestible pieces than would have been possible without using tools.

“Eating meat and using stone tools to process food apparently made possible key reductions in the jaws, teeth and chewing muscles that occurred during human evolution,” Zink said.

But testing a process as basic as chewing isn’t as easy – or as attractive – as it might sound.

“What Katie did was creative but sometimes, frankly, a little stomach-churning,” Lieberman said. “Not only did she have people come into the lab, chew raw meat and other foods, and spit them out, but then she had to analyze the stuff.”

It wasn’t just any food – or any meat – that subjects noshed on.

To approximate the toughness and texture of the game that early humans ate, Zink and Lieberman (after much experimentation) settled on using goat – which subjects chewed raw while Zink used instruments attached to their jaw to measure the effort involved.

In each trial, volunteers were given, in random order, a selection of foods prepared in several ways – raw, sliced, pounded and cooked goat, as well as several vegetables, including carrots, beets and yams. After chewing each morsel until they would normally swallow, subjects spit out the food. Zink then spread the individual food particles out onto a tray, photographed them, and digitally measured their sizes.

“What we found was that humans cannot eat raw meat effectively with their low-crested teeth. When you give people raw goat, they chew and chew and chew, and most of the goat is still one big clump – it’s like chewing gum,” Lieberman said. “But once you start processing it mechanically, even just slicing it, the effects on chewing performance are dramatic.”

But why study chewing at all?

“Chewing is one of the key characteristics of being a mammal,” Lieberman explained. “Most other animals, like reptiles, barely chew their food — they just swallow it whole. The evolution of the ability to chew food into smaller particles gave mammals a big boost of extra energy because smaller particles have a higher surface area to volume ratio, allowing digestive enzymes to then break food down more efficiently.”

Most mammals, however, eat a relatively low-quality diet- think of cows eating grass and hay – that they need to spend most of the day chewing. Even humans’ closest ape relatives, with a diet that consists mainly of fruit, must spend nearly half their day chewing to extract enough energy from their food, Lieberman said.

“But we humans have done something really remarkable,” he said. “We eat even higher-quality foods than chimpanzees, and spend an order of magnitude less time chewing them.”

Making that change, however, presented early humans with a new challenge.

One of the critical components of that higher-quality diet is meat, which – despite being calorically dense – is very difficult for humans to chew effectively.

“Meat has a lot of nutrients, but it is also very elastic. You can think of it as being like a rubber band,” Zink said. “So the problem is that we can’t break it down with our flat, low-cusped teeth. But if you slice it up, then you do not need to use your teeth to break it down as much, and you swallow much smaller particles. Cooking makes chewing even easier.”

That pre-processing, and the reductions in chewing effort that came with it, Zink and Lieberman said, may have opened the door to one of the most important lifestyle changes in human evolution – the emergence of hunting and gathering.

“With the origin of the genus Homo…we went from having snouts and big teeth and large chewing muscles to having smaller teeth, smaller chewing muscles, and snoutless faces” Lieberman said. “Those changes, and others, allowed for selection for speech and other shifts in the head, like bigger brains. Underlying that, to some extent, is the simplest technology of all: slicing meat into smaller pieces, and pounding vegetables before you chew them.”

The impact that higher-quality diets and easier chewing could have on early humans is clear if you imagine what day-to-day life might have been like millions of years ago.

“Suppose you go out hunting for antelopes like impala or kudu, but at the end of the day you come back empty-handed, which happened fairly often for early humans,” Lieberman said. “Chimps couldn’t survive that way – they would then have to spend all night eating.

“Following the invention of hunting and gathering, though, humans can benefit from a division of labor,” he continued. “Someone else may have come back with an impala, or some tubers you could eat. And instead of spending all night eating it, you’d spend a lot less time, energy and effort to chew it by pounding it or cutting it with just a few stone stone tools. What a dramatic shift!”

Though many aspects of our biology changed when the genus Homo evolved, Zink and Lieberman said that processing food before eating almost surely played a significant role.

“One of the innovations that helped make us human is cutting up and pounding our food,” Lieberman said. “Extra-oral processing first by using stone tools and then by cooking played a very important role in human evolution because it released selection for big faces and big teeth, which then enabled selection for shorter faces which were important for speech, and enabled us to grow big brains and have large bodies. We are partly who we are because we chew less.”

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