244 CHAPTER 10 | The Neolithic Revolution: The Domestication of Plants and Animals
new locations brought other things as well, including lan-
guages, beliefs, and new alleles for human gene pools.
A similar spread occurred from West Africa to the
southeast, creating the modern far-reaching distribu-
tion of speakers of Bantu languages. Crops including
sorghum (so valuable today it is grown in hot, dry areas
on all continents), pearl millet, watermelon, black-eyed
peas, African yams, oil palms, and kola nuts (source of
modern cola drinks) were first domesticated in West
Africa but began spreading eastward by 5,000 years ago.
Between 2,000 and 3,000 years ago, Bantu speakers with
their crops reached the continent’s east coast and a few
centuries later reached deep into what is now the coun-
try of South Africa. Being well adapted to summer rains,
African crops spread no further, for the Cape of South
Africa has a Mediterranean climate with winter rains.The Culture of Neolithic
Settlements
A number of Neolithic settlements have been excavated,
particularly in Southwest Asia. The structures, artifacts,
and food debris found at these sites have revealed much
about the daily activities of their former inhabitants as
they pursued the business of making a living. Perhaps the
best known of these sites is Jericho, an early farming com-
munity in the Jordan River Valley.Jericho: An Early Farming Community
Excavations at the Neolithic settlement that later grew to
become the biblical city of Jericho revealed the remains of
a sizable farming community inhabited as early as 10,350
years ago. Here, in the Jordan River Valley, crops could be
grown almost continuously, due to the presence of a boun-
teous spring and the rich soils of an Ice Age lake that had
dried up some 3,000 years earlier. In addition, flood-borne
deposits originating in the Judean highlands to the west
regularly renewed the fertility of the soil.
To protect against these floods and associated mud-
flows, as well as invaders, the people of Jericho built mas-
sive walls of stone surrounding their settlement.^23 Within
these walls, which were 2 meters (6½ feet) wide and
almost 4 meters (12 feet) high, and behind a large rock-
cut ditch, which was 8 meters (27 feet) wide and 2¾ me-
ters (9 feet) deep, an estimated 400 to 900 people lived in
houses of mud brick with plastered floors arranged aroundThe Spread of Food
Production
Paradoxically, although domestication increases pro-
ductivity, it also increases instability. This is so because
those varieties with the highest yields become the focus of
human attention, while other varieties are less valued and
ultimately ignored. As a result, farmers become depen-
dent on a rather narrow range of resources, compared to
the wide range utilized by food foragers. Today, this range
is even narrower. Modern agriculturists rely on a mere
dozen species for about 80 percent of the world’s annual
tonnage of all crops.^22
This dependence upon fewer varieties means that
when a crop fails, for whatever reason, farmers have less
to fall back on than do food foragers. Furthermore, the
likelihood of failure is increased by the common prac-
tice of planting crops together in one locality, so that a
disease contracted by one plant can easily spread to oth-
ers. Moreover, by relying on seeds from the most pro-
ductive plants of a species to establish next year’s crop,
farmers favor genetic uniformity over diversity. The re-
sult is that if some virus, bacterium, or fungus is able
to destroy one plant, it will likely destroy them all. This
is what happened in the Irish potato famine of 1845 to
1850, which caused the deaths of about a million people
due to hunger and disease and forced another 2 million
to abandon their homes and emigrate. The population
of Ireland dropped from 8 million before the famine to
5 million afterward.
This concentration of domesticates and the conse-
quent vulnerability to disease intensify with contem-
porary agribusiness and factory farming. This chapter’s
Globalscape examines the role of pig farming in the cur-
rent swine flu pandemic that began to sweep the world
early in 2009.
The Irish potato famine illustrates how the combina-
tion of increased productivity and vulnerability may con-
tribute to the geographic spread of farming. Time and time
again in the past, population growth, followed by crop
failure, has triggered movements of people from one place
to another, where they have reestablished their familiar
subsistence practices. Once farming came into existence,
its spread to neighboring regions through such migra-
tions was more or less guaranteed. From Southwest Asia,
for instance, farming spread northwestward eventually to
all of Europe, westward to North Africa, and eastward to
India. Domesticated variants also spread from China and
Southeast Asia westward. Those who brought crops to
(^22) Diamond, Guns, germs, and steel, p. 132.
(^23) Bar-Yosef, O. (1986). The walls of Jericho: An alternative interpretation.
Current Anthropology 27, 160.