Modified: 2010-01-30
Today humans could not live without farming. The amount of food produced by farming worldwide is sufficient to sustain the entire human population, although many people are still malnourished and many still starve. But, it is not the lack of food that causes malnutrition or starvation; it is the problem of distributing the available food to where it is needed. Wars and natural disasters can disrupt existing food distribution networks causing local pockets of malnutrition or starvation. Economic downturns, too, can cause food shortages. For now, at least, there is enough food to feed all people on the planet; the trick is to get it to those who need it (World Hunger Education Service, 2009).
We already know that our earliest ancestors were hunter-gatherers. At some point in the past, our species nearly completely abandoned that lifestyle and adopted farming. That change in lifestyle was gradual and began around 10,000 years ago. The underlying logic behind the adoption of farming is not clear. For one thing, evidence from modern hunter-gatherers shows that they spend less time and effort “working” to sustain themselves than do non-mechanized modern farmers (Stuart, 1997) Also, modern-hunter gatherers also cultivate wild plants (meaning they water them or weed them) and plant seasonal gardens. Presuming that the same difference in workload between hunter-gathering and farming held in the distant past, why would hunter-gatherers wish to become farmers? Let’s look at climate first. The Last Glacial Maximum (LGM), or the point of maximum extent of the last Ice Age, was 18,000 years ago. Note that after the LGM, global average temperatures slowly rose and peaked until about 11,000 years ago. Average temperatures then dropped again for over 1,000 years (a period known as the Younger Dryas). For the last 6,000 years, the global average temperature has remained relatively warm and constant. Today, scientists and world leaders worry that the average global temperature may be rising to new, record, high levels due to human production of carbon dioxide and other industrial gases, the phenomenon of global warming. Dramatic worldwide temperature swings are nothing new, however. They have occurred about every 100,000 years over the last 1 million years, however those temperature swings were regulated by natural cycles not by effects caused by human technology (Petit, et al., 1999). Those naturally occurring climate oscillations may have been partly responsible for moving hunter-gatherers into a new lifestyle, sedentism, after the LGM.
Figure 2.4 shows global temperatures from 400,000 years ago to the present.
Holmes (2004) suggests additional reasons for the long and gradual switch to farming: competitive feasting, the new cultivated crops were a kind of luxury good; brewing beer, the grains grown were converted into beer, not eaten; and the new foods sprung a population trap, once people farmed, they had more children and could not easily return to a hunter-gatherer lifestyle. The earliest archeological evidence of sedentism, or when human groups began to live in one place, dates from about 11,000 years ago. Alongside the Euphrates River at a village called Abu Huyreyra (in northern Syria), people formed one of the first communities based on farming. They built mud houses, hunted migrating gazelles, planted wheat and barley, and domesticated sheep and goats (Moore, Hillman, & Legge, 2000). The village lasted for thousands of years, although at one point it was abandoned and later re-established.
Figure 2.5 shows some of the excavated ruins of this village.
Marginal definition: Sedentism—a human lifestyle associated with largely remaining in one place or locality with food production based on farming plants and livestock.
Also important to sedentism was the domestication of plants and animals. Domestication is the process of regulating breeding of plants and animals. Domestication has been successful to only with a limited number of species. Diamond (1997, p. 132) writes, “A mere dozen species account for over 80 percent of the world’s annual tonnage of all crops. Those dozen blockbusters are the cereals wheat, corn, rice, barley, and sorghum; the pulse soybean; the roots or tubers potato, manioc, and sweet potato; the sugar sources sugarcane and sugar beet; and the fruit banana.” Similarly, only a few species of terrestrial herbivores have been domesticated as well. He states, “Only 5 species became widespread and important around the world. Those Major Five of mammal domestication are the cow, sheep, goat, pig, and horse (p. 159).” Notice that domestic plants and animals provided more than just food. Some plants (e.g., flax and cotton) provided the raw materials for fabrics. Animals also provided muscle power, raw materials for fabric (e.g., wool and hides), milk, and organic fertilizer.
The domestication of plants need not have been accomplished with forethought. In the case of the wild wheats, whose seeds shatter (drop from the plant) easily, early harvesters may have unintentionally altered the reproductive success of genetic variants whose seeds did not shatter by only cutting late maturing plants, and perhaps later planting seeds left over from those plants (Mithen, 2004). Eventually, domestication did become intentional. For plants, that meant saving some seeds for their desired genetic properties and planting them at the optimal time. Similarly, animals were domesticated by selective breeding—allowing animals with desirable genetic characteristics to mate while denying that opportunity to those animals with less desirable genetic traits. Realize, of course, that no scientific knowledge of genetics is necessary to accomplish domestication.
The first continuously inhabited towns date from around 9,000 years ago. Jericho, in what is now Israel, holds the distinction of being the oldest continuously occupied town in the world. Slowly but surely, most humans abandoned the hunter-gatherer lifestyle as towns and cities grew. As will be noted below, it has only been very recently that more people lived in cities than outside of them. However, even those who lived outside of towns and cities were caught up in the process of urbanization. Farmers, for example, sold or traded their surplus crops in urban markets. In other words, once urbanization began human lifestyles changed radically, a process that continues to the present day.
