The Great Dispersal, Part 1: The Push and Pull of Environmental Degradation

 

Previously in Cheese, Culture and Beyond we reconstructed the dawn of the Neolithic Age. By around 8000 BC, a subsistence strategy founded upon crop cultivation and domestication, livestock herding and domestication, and dairying and cheesemaking, arose for the first time in the Fertile Crescent region of Southwest Asia. The resulting sedentary mixed farming model proved exceptionally successful; indeed, too successful because it resulted in a population surge that soon strained the local environment.

By the start of the seventh millennium BC, the remarkable success of these Neolithic first farmers reached a tipping point, especially in the southern Levant where environmental collapse set in due to overpopulation, loss of soil fertility, and widespread erosion resulting from deforestation and overreliance on goat herding. Particularly troublesome was the browsing behavior of goats, which destabilized plant communities that anchored the fragile landscape and prevented reforestation, which led to severe erosion.

Threatened by crop failures, some Neolithic communities increasingly shifted away from sedentary mixed farming to mobile pastoralism that relied heavily on nomadic and semi-nomadic livestock grazing and milk production. Mobile pastoralism enabled struggling farmers to take advantage of vast expanses of surrounding unused marginal lands that were poorly suited for crop cultivation but could support nomadic sheep and goat grazing. Thus, dairying and cheesemaking became uncoupled with sedentary crop cultivation for the first time.

Around the same time during the seventh millennium, the discovery of pottery technology enabled early cheesemakers, who up to this point produced only acid coagulated cheese, to stumble upon coagulation caused by the combined action of acid and heat, which is the principle behind Ricotta-type cheeses. The advent of pottery made it possible to heat liquids over an open fire, which inspired new techniques in cooking and led to much experimentation with the heating of various foodstuffs, as evidenced by the presence of soot and pyrolytically formed organic residues in Neolithic pottery fragments. Early experiments with heating milk to near boiling and allowing the milk to cool and ferment in the warm environment of southwest Asia, likely led to the discovery of yogurt around this time. Yogurt probably attracted Neolithic interest because it is far more digestible for adults with lactose intolerance than is unheated liquid milk due to the selective action on heat tolerant lactic acid bacteria that survive in heated milk and which subsequently proliferate during yogurt fermentation. Yogurt opened the door for adults and older children to benefit from the remarkable nutritional value of milk with few side effects caused by lactose intolerance.

With the discovery of yogurt-making, it was also only a matter of time before Neolithic communities discovered that yogurt separates more easily into butter and buttermilk during churning than unheated milk. This is especially true for goat and sheep milk which are notoriously difficult to churn because of the small size of their milkfat globules and their inability to clump together and rise as a concentrated cream layer. Therefore, sheep and goat milk require great physical exertion for long spans of time to obtain butter. In contrast, yogurt making renders the churning of butter from goat and sheep milk much more practical. Butter, in turn, became a precious foodstuff because it was easily purified into butteroil (ghee) that resisted spoilage and could also be used as a cooking oil. Indeed, butteroil was, and is, revered in regions of the Near East and beyond where olive oil and other plant-based oils were rare or completely unavailable. Butteroil thus became an essential component of nomadic food culture and the overall pastoral subsistence strategy that emerged in the seventh millennium as farmers abandoned their failing Fertile Crescent farms and moved into ever more distant dry rangelands where olive oil was no longer available.

The buttermilk that separated during butter making was another product that undoubtedly intrigued the inventive Neolithic farmers. Since they already had learned to boil fresh milk in the making of yogurt, it probably didn’t take them long to boil the partially fermented buttermilk, thereby producing the right combination of acidity and temperature to cause the coagulation of milk proteins and enabling the production of acid/heat-coagulated cheese as a coproduct of butteroil production. To this day, butteroil and acid-heat coagulated cheese are widely produced by nomadic and semi-nomadic pastoral communities as co-products through the ancient processing sequence of churning yogurt from sheep and goat milk into butter and buttermilk, and further processing into butteroil and acid-coagulated cheese, respectively.

Acid-coagulated and acid/heat-coagulated cheeses are very high in moisture content and therefore spoil rapidly due to uncontrolled microbial growth, especially in the warm climate of Southwest Asia. Therefore, these early cheeses were consumed fresh. However, if salted and dried in the sun, they can also be preserved indefinitely, as is still widely practiced today in the Near East. The dried cheeses are very hard, almost indestructible, but well suited for grating into soups and stews. Alternatively, acid coagulated and acid-heat coagulated fresh cheeses can be preserved by salting and packing tightly in airtight packaging and then storing in a way that limits exposure to high ambient temperatures. In Turkey, for example, traditional acid-coagulated and acid/heat- coagulated cheeses are still salted and sealed in airtight ceramic pots that are buried in the ground to preserve and ripen the cheese and shield the contents from the heat. Bags made from animal skins may also have been used to store and ripen soft cheeses, as is still practiced traditionally in Turkey today.

Bottom line is that the technology to produce acid coagulated and acid-heat coagulated cheeses and butteroil enabled the extraordinary nutritional value of milk to be preserved and stockpiled, thus serving as a vital insurance policy against crop failures and, as a last resort, enabling sedentary mixed agricultural communities to abandon their failing farms and pivot to a nomadic or semi-nomadic subsistence strategy out on surrounding and otherwise inhospitable dry rangelands and desert.

Consequently, when farming communities experienced environmental collapse during the seventh millennium BC, waves of migration out of the Fertile Crescent to surrounding marginal lands gave birth to a new mobile pastoral subsistence strategy that remains deeply entrenched there to this day. The domesticated livestock that these Neolithic wanderers brought with them, especially their dairy animals, enabled displaced communities to adapt, survive and even thrive in rather inhospitable environments as they ultimately relocated eastwards over thousands of miles.

Eastward Migration
Eastward migration out of the Fertile Crescent through the dry rangelands of south-central Asia began early in the seventh millennium BC, moving rapidly through Iran, Afghanistan, and eventually reaching the fertile Indus River Valley of eastern Pakistan by around 6500 BC. There, the Neolithic newcomers resumed their former mixed agricultural way of life based on crop cultivation and dairying and cheesemaking. The archaeological record of great Harappan civilization that eventually arose in the Indus River Valley during the third millennium BC confirms that cheesemaking was still taking place in the Valley. In the vast stretches of dry rangelands that extend from the borders of the Fertile Crescent to the Indus River Valley, nomadic and semi-nomadic pastoralism became a permanent feature of the rugged landscape. There, the traditional pastoral processing sequence of yogurt production followed by churning to produce butter and buttermilk, with the butter then used to produce butteroil and buttermilk used to produce acid-heat coagulated cheese, became a centerpiece of the mobile pastoralist subsistence strategy that continues in these regions to this day.

Northward Migration
Migration northward out of the environmentally challenged Levant into eastern Anatolia (modern Turkey) also occurred by the middle of the seventh millennium BC. From there they expanded westwards throughout Anatolia, including the northwest region along the fertile shores of the Sea of Marmara, where they settled and resumed their sedentary mixed agricultural way of life based on crop cultivation, small scale livestock herding, dairying and cheesemaking. The comparatively lush environment of northwest Anatolia enabled the new arrivals to shift their livestock emphasis from small ruminants to cattle. Dairying and cheesemaking continued but now focused on the production of cow’s milk, acid coagulated cheese, and butteroil plus acid-heat coagulated cheese via the processing sequence described previously. These communities flourished, populations grew, milk flowed freely, and life was good. I like to think of this period in Anatolia during the seventh millennium BC as the golden age of Neolithic cheesemaking. However, it did not last long, as we shall see in The Great Dispersal, Part 2.