Conservation Biology

Sunday, August 13, 2006


“What the Ancients did for us” is a documentary series by the Open University and the BBC in Great Britain. This episode focused on the Mesopotamians, the first civilizations that settled in the Fertile Crescent. What did these first civilizations bring us? According to the documentary they brought us agriculture, permanent settlements, the wheel (first used for chariots), warfare, irrigation systems, dams, the first written language, baked clay bricks… the list seems endless. But what impact did these inventions have on the human race and on the environment? I would like to focus on one and that is agriculture, as I believe it is the single one thing that set a whole chain reaction in motion that changed the course of humanity.

What was the Neolithic Revolution? The term was first used by Vere Gordon Childe (1936) in his book “Man makes himself”. According to Mannion (1999) Childe used the term to highlight the importance of the origin of agriculture. The Neolithic Revolution is also referred to as the birth of civilization, where civilization is said to be “an organized society”. Who were these people and what made them civilized? The Sumerian or Mesopotamian civilization was born from the first people that abandoned their hunter-gatherer lifestyles to settle down in one place and take up farming (Holmes, Maxwell and Scoones 2004). Mesopotamia lay in the “Fertile Crescent” with the Tigris and the Euphrates rivers supplying water and the fertile banks between the two rivers providing suitable soil for domesticating crops. The Fertile Crescent ran from the Persian Gulf through what is now Iraq, Syria, Lebanon and Israel to the Mediterranean Sea, also encompassing parts of Iran and Turkey. There has been much speculation as to where agriculture originated, but according to a recent study by Pinhasi et al. (2005) this can now be firmly placed in the Fertile Crescent. (Normile (1997) questioned if they were indeed the first to cultivate crops as evidence in China suggests that rice might have been cultivated there some 11 000 years ago.)

What exactly drove people to this new lifestyle some 10 000 years ago? Was it the environmental instability that followed after the end of the last ice age that necessitated people to become more innovative (Mannion 1999) or maybe a realization by some people that farming could produce an assured food supply in a much smaller area than what was needed to support a family with a nomadic lifestyle (Holmes, Maxwell and Scoones 2004)? Was it the milder climate that eventually followed after the last ice age came to an end that made that area particularly suitable for rearing crops? What could have triggered the change from an egalitarian hunter-gatherer lifestyle to one with distinct social classes, where the elite ruled? Was it population growth that came first or did agricultural practices lead to an explosion in the human population? Or could the dump-heap hypothesis of Anderson (1956) (mutual benefit of plants and humans that developed passively) still hold some merit? Since the early 20th century, two hypotheses have dominated the theories behind the advent of agriculture. They were termed the “need or greed” theories by Mannion (1999), where the “need” refers to Childe and others’ belief that environmental factors led to agricultural practices and the “greed” to Nikolai Vavilov’s work in the 1940’s that implies that cultural or materialistic factors played a leading role (Vavilov 1992).

Nobody seems to be able to come up with a definite answer (Mannion 1999) and it was probably a combination of factors that lead to the rise of agricultural practices. What is important though, is that the idea seemed to have cottoned on rather quickly and within a period of no more than a thousand years some small permanent settlements had grown to large ones (Holmes, Maxwell and Scoones 2004). It was within these communities that new skills and ideas were developed that would have a profound and irrevocable impact on human society and the environment as a whole.

Why focus on agriculture? From what I have read, it just stands out again and again as the one factor that just snowballed and within a little over 1000 years had spread to almost all corners of the earth. How it spread is still debated. Some say through the movement of populations (demic dispersal/diffusion) (Cavalli-Sforza 1996; Pinhasi et al. 2005) and others through imitation (cultural diffusion). Again, to me it is not as important as to how agricultural practices spread, but rather the fact that they did spread. According to Hannah et al. (1994) more than 75% of the earth’s habitable land surface has been disturbed to some extent by humans. It is now more than ten years later since that paper was written and this percentage will have certainly gone up even further. Especially if one takes into account that in 1996 the World Resource Institute’s estimate of annual deforestation in the tropics alone was around 8%. Agriculture is thus by far the biggest cause of land transformation and therefore the biggest cause of environmental decay (Mannion 1999; ) Agriculture gave rise to wealth and social classes (Gowdy 1995) and even today is still one of the main sources of wealth generation (Mannion 1999). I therefore cannot but agree with Mannion (1999) and Childe (1936) that the advent of agriculture was the turning point in environmental and cultural history. It was agriculture in the form of crop cultivation and later also domestication of animals that allowed people to settle more permanently. Permanent settlement and population growth however also brought about a change in human culture. People moved from an egalitarian, socially equal society to a socially divided community, where social classes where soon established and the elite ruled (Gowdy 1995). Surplus food production gave rise to trade in items being used to reinforce social standing, whereas trade between egalitarian communities were probably limited to utilitarian items (Gowdy 1995).

According to Gowdy (1995) trade and environmental sustainability just do not seem to go together very well. It is a pattern that has repeated itself in prehistory and history since the inception of agriculture; wealth generation through agriculture, a rapid growth in the population, the elite in the society taking control of the surplus, wide trade and overexploitation. Eventually environmental decay sets in that just does not allow societies to cope with natural phenomena such as droughts or floods and the outcome is inevitable, societal collapse (Ponting 1991; Weiss et al. 1993; Gowdy 1995). Mannion (1999) agrees that even in prehistoric times, agriculture has been associated with overexploitation where soil erosion, water pollution, desertification and soil degradation eventually led people to abandon their settlements and migrate to greener pastures. (All this does sound awfully familiar… Isn’t that exactly what the world is now experiencing at a global scale? Overexploitation can be seen everywhere, the only difference is we have nowhere to migrate to!)

Apart from wealth creation on the one hand and environmental decay on the other, agriculture has probably also played a major role in the spread of diseases. The fact that many people were living together in relatively small spaces, made them ideal hosts for many pathogens (Mira et al 2006). In this paper the authors postulate that selective pressure could have transformed general pathogens to host specific pathogens during the Neolithic revolution. The regular transfer of pathogens from animals to humans and visa versa probably also occurred for the first time around this period.

So what did agriculture bring us? It paved the way for many new technologies that included pottery and metal technology that improved man’s ability to manipulate the environment according to his needs (Mannion 1999). Are we any better off though? Are we happier people than the hunter-gatherers that lived in prehistoric times? Did greed indeed follow need? Some of us (the developed world) might face less hardship now, but our greed has transformed the world and is continuing to transform the world where the rich are getting richer and the poor poorer…


Anderson E. 1956. Man as a maker of new plants and plant communities. In Thomas, WA Jr (editor). Man’s role in changing the face of the earth. Chicago, IL: University of Chicago Press. p363–77.

Cavalli-Sforza LL. 1996. The spread of agriculture and nomadic pastoralism: insights
from genetics, linguistics and archaeology. In Harris DR (editor). The origins and spread of agriculture and pastoralism in Eurasia. London: UCL Press. p51–69.

Childe VG. 1936. Man makes himself. London: Watts.

Gowdy JM. 1995. Trade and Environmental Sustainability: An Evolutionary Perspective. Review of Social Economy Vol LIII (4):493-510.

Holmes M , Maxwell G and Scoones T. 2004. The birth of civilization. In: Nile. London: BBC Books. p31-34.

Mannion AM. 1999. Domestication and the origins of agriculture: an appraisal. Progress in Physical Geography 23(1):37–56

Mira A, Pushker R and Rodriguez-Valera F. 2006. The Neolithic revolution of bacterial genomes. Trends in Microbiology 14(5):200-206.

Normile D. 1997. Yangtze seen as earliest rice site. Science 275:309.

Pinhasi R, Fort J and Ammerman AJ. 2005. Tracing the origin and spread of agriculture in Europe. PLoS Biology 3(12): 2220-2228.

Ponting C. 1991. A Green History of the World. New York: Penguin Books.

Vavilov NI. 1992. Origin and geography of cultivated plants. Cambridge: Cambridge
University Press.

Weiss H, Courty M-A, Wetterstrom W, Guichard F, Senior L, Meadow
R, and Currow A. 1993 The Genesis and Collapse of Third Millennium
North Mesopotamian Civilization. Science 261: 995-1004.

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Karen Marais
BCB Hons NISL student
University of the Western Cape
Private Bag X17