Wedged in between dump trucks and excavators, archeologist Birgit Srock is drawing the outline of a 7,200-year-old posthole. A concrete mixing plant is visible on the horizon. She is here because, during the construction of a high-speed rail line between the German cities of Nuremberg and Berlin, workers happened upon a large Neolithic settlement in the Upper Franconia region of northern Bavaria.
The remains of more than 40 houses were unearthed, as well as skeletons, a spinning wheel, bulbous clay vessels, cows' teeth and broken sieves for cheese production -- a typical settlement of the so-called Linear Pottery culture (named after the patterns on their pottery).
This ancient culture provided us with the blessing of bread baking. At around 5300 BC, everyone in Central Europe was suddenly farming and raising livestock. The members of the Linear Pottery culture kept cows in wooden pens, used rubbing stones and harvested grain. Within less than 300 years, the sedentary lifestyle had spread to the Paris basin.
The reasons behind the rapid shift have long been a mystery. Was it an idea that spread through Central Europe at the time, or an entire people?
Peaceful Cooperation or Invasion?
Many academics felt that the latter was inconceivable. Agriculture was invented in the Middle East, but many researchers found it hard to believe that people from that part of the world would have embarked on an endless march across the Bosporus and into the north.
Jens Lüning, a German archaeologist who specializes in the prehistoric period, was influential in establishing the conventional wisdom on the developments, namely that a small group of immigrants inducted the established inhabitants of Central Europe into sowing and milking with "missionary zeal." The new knowledge was then quickly passed on to others. This process continued at a swift pace, in a spirit of "peaceful cooperation," according to Lüning.
But now doubts are being raised on that explanation. New excavations in Turkey, as well as genetic analyses of domestic animals and Stone Age skeletons, paint a completely different picture:
Mutated for Milk
The new settlers also had something of a miracle food at their disposal. They produced fresh milk, which, as a result of a genetic mutation, they were soon able to drink in large quantities. The result was that the population of farmers grew and grew.
These striking insights come from biologists and chemists. In a barrage of articles in professional journals like Nature and BMC Evolutionary Biology, they have turned many of the prevailing views upside down over the course of the last three years.
The most important group is working on the "Leche" project (the name is inspired by the Spanish word for milk), an association of 13 research institutes in seven European Union countries. The goal of the project is to genetically probe the beginnings of butter, milk and cheese.
An unusual circumstance has made this research possible in the first place. Homo sapiens was originally unable to digest raw milk. Generally, the human body only produces an enzyme that can break down lactose in the small intestine during the first few years of life. Indeed, most adults in Asia and Africa react to cow's milk with nausea, flatulence and diarrhea.
But the situation is different in Europe, where many people carry a minute modification of chromosome 2 that enables them to digest lactose throughout their life without experiencing intestinal problems. The percentage of people with this modification is the highest among Britons and Scandinavians (see graphic).
It has long been known that these differences are based on Europeans' primeval origins. But where did the first milk drinker live? Which early man was the first to feast on cow's milk without suffering the consequences?
Groups Did not Intermingle
In a bid to solve the mystery, molecular biologists have sawed into and analyzed countless Neolithic bones. The breakthrough came last year, when scientists discovered that the first milk drinkers lived in the territory of present-day Austria, Hungary and Slovakia.
But that was also where the nucleus of the Linear Pottery culture was located. "The trait of lactose tolerance quickly became established in the population," explains Joachim Burger, an anthropologist from the University of Mainz in southwestern Germany who is a member of the Leche team.
Deep-frozen thighs are stacked in Burger's laboratory, where assistants wearing masks saw open skulls. Others examine bits of genetic material from the Stone Age under a blue light.
The group will hold a working meeting in Uppsala, Sweden in November. But even at this stage it is already clear that large numbers of people from the Middle East once descended upon Central Europe.
There are also signs of conflict. The intruders differed from the continent's Ice Age inhabitants "through completely different genetic lines," Burger explains. In other words, the two groups did not intermingle.
Tension Between Locals and IncomersThis isn't exactly surprising. The old hunter-gatherers on the continent had long been accustomed to hunting and fishing. Their ancestors had entered Europe 46,000 years ago -- early enough to have encountered the Neanderthals.
The early farmers moving into Central Europe were sophisticated compared with these children of nature. The farmers wore different clothing, prayed to other idols and spoke a different language.
It was these differences that probably led to tensions. Researchers have discovered that arsonists set the villages of the Linear Pottery culture on fire. Soon the farmers built tall palisades to protect their villages. Their advance was blocked for a long time by the Rhine River, however.
There are signs that bartering and trade existed, but the two groups did not intermingle sexually. Burger suspects that there was probably a "strict ban on intermarriage."
The farmers even protected their livestock from outside influences, determined to prevent the wild oxen known as aurochs from breeding with their Middle Eastern cows. They feared that such hybrids would only introduce a new wild element into the domesticated breeds.
Their breeding precautions were completely understandable. The revolutionary idea that man could subjugate plants and animals went hand in hand with enormous efforts, patience and ingenuity. The process took thousands of years.
Getting Animals Under Control
The beginnings can now be delineated relatively well. About 12,000 years ago, the zone between the Zagros Mountains in present-day Iran, Palestine and Turkey was transformed into a giant field experiment.
The first farmers learned to cultivate wild emmer and einkorn wheat. Then they went on to domesticate animals. Goats had been successfully domesticated in Iran by about 9,000 BC. Sheep and pigs were domesticated in southern Anatolia.
Enormous settlements soon sprang up in the region known as the Fertile Crescent. Çatalhöyük, known as "man's first metropolis," had about 5,000 inhabitants, who lived in mud huts packed tightly together. They worshipped an obese mother goddess, depicted in statues as a figure sitting on a throne decorated with the heads of carnivores.
One of the most difficult challenges was the breeding and domestication of Middle Eastern wild cattle. The male specimens of the species weighed up to 1,000 kilograms (2,200 pounds) and had curved horns. People eventually drummed up the courage to approach the beasts somewhere in the central Euphrates Valley.
They found different ways of getting the cattle under control. One Neolithic sculpture depicts a steer with a hole punched through its nasal septum. Removing the testicles was also quickly recognized as a way of improving the animals' temperament. Once the wild cattle had been castrated, they could finally be yoked.
The clever farmers realized that if they gave calves from other mothers to the cows, their udders would always be full of milk.
No Taste for Milk
Oddly enough, the Mesopotamian farmers didn't touch fresh milk. A few weeks ago, Joachim Burger returned from Turkey with a sack full of Neolithic bones from newly discovered cemeteries where the ancient farmers were buried.
When the bones were analyzed, there were no signs of lactose tolerance. "If these people had drunk milk, they would have felt sick," says Burger. This means that at first the farmers only consumed fermented milk products like kefir, yogurt and cheese, which contain very little lactose.
Even more astonishing, as recent excavations in Anatolia show, is the fact that the ancient farmers did not leave their core region for almost 2,000 years. They had put together the complete "Neolithic cultural package," from the rubbing stone to seeds, "without advancing into other areas," says archeologist Mehmet Özdogan.
The coastal zones were long avoided. The people who lived there were probably fishermen who defended themselves against the new way of life with harpoons.
The crossing of the Bosporus did not occur until sometime between 7000 and 6500 BC. The farmers met with little resistance from the hunter-gatherer cultures, whose coastal settlements were being inundated by devastating floods at the time. Melting glaciers had triggered a rise in the sea level of over 100 meters (330 feet).
Nevertheless, the advance across the Balkans was not a triumph. The colonists' dwellings there seem small and shabby. At the 47th parallel north, near Lake Balaton in modern-day Hungary, the advance came to a standstill for 500 years.
The Linear Pottery culture, which was the first to shift to the northern shore of Lake Balaton, gave the movement new life. Lüning talks about "renegade" settlers who had created a "new way of life" and a "reform project" on the other side of the lake.
With military determination, the advancing pioneers constantly established new settlements. The villages often consisted of three to six windowless longhouses, strictly aligned to the northwest, next to livestock pens and masterfully constructed wells. Their tools, picks and bowls (which were basically hemispheric vessels) were almost identical throughout Central Europe, from Ukraine to the Rhine.
Migration and Mass MurderThe settlers, wielding their sickles, kept moving farther and farther north, right into the territory of backward peoples. The newcomers were industrious and used to working hard in the fields. Clay statues show that the men were already wearing trousers and shaving. The women dyed their hair red and decorated it with snail shells. Both sexes wore caps, and the men also wore triangular hats.
By comparison, the more primitive existing inhabitants of the continent wore animal hides and lived in spartan huts. They looked on in bewilderment as the newcomers deforested their hunting grounds, tilled the soil and planted seeds. This apparently upset them and motivated them to resist the intruders.
In the Bible, Cain, the crop farmer, slays Abel the shepherd. In the Europe of the Neolithic Age, conditions may have been just as violent. One of the most gruesome discoveries is a mass grave that has been dubbed the "Talheim Death Pit" in the German town of that name. The pit is filled with the remains of 34 bodies. The members of an entire clan were apparently surprised in their sleep and beaten to death with clubs and hatchets. So far, archeologists haven't been able to figure out whether the incomers killed the existing inhabitants, or vice versa.
Drinking Milk by the Bucketful
It is clear, however, that the dairy farmers won out in the end. During their migration, they encountered increasingly lush pastures, a paradise for their cows. An added benefit of migrating farther to the north was that raw milk lasted longer in the cooler climate.
This probably explains why people soon began drinking the abundant new beverage by the bucketful. Some had genetic mutations that enabled them to drink milk without getting sick. They were the true progenitors of the movement.
As a result of "accelerated evolution," says Burger, lactose tolerance was selected for on a large scale within the population in the space of about 100 generations. Europe became the land of the eternal infant as people began drinking milk their whole lives.
The new food was especially beneficial for children. In the Neolithic Age, many small children died after being weaned in their fourth year of life. "As a result of consuming healthy milk, this could be greatly reduced," Hamburg biologist Fritz Höffeler speculates. All of this led to population growth and, as a result, further geographical expansion.
Does this explain why the inventors of the sickle and the plow conquered Europe so quickly, leading to the demise of the old hunter-gatherers?
Imagine, if you will, a village of the Linear Pottery culture in the middle of winter. As smoke emerges from the top of a wooden hut, the table inside is surrounded by rosy-cheeked children drinking hot milk with honey, which their mother has just prepared for them. It's an image that could help explain why people adopted a sedentary way of life.
Burger, at any rate, is convinced that milk played a major part in shaping history, just as gunpowder did much later. "There was once a white revolution," he says.
Translated from the German by Christopher Sultan
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