leguminous grains. None of the New World’s complex
societies—Incas, Mayas, or Aztecs—acquired the first two
traits, but their cropping was often more productive than
harvests in Europe and Asia.
Many cattle breeds provided draft power, both for
field work and for transportation. They also supplied
milk, but they were too valuable to be slaughtered for
meat unless they got very old. Horses were used exten-
sively in war from antiquity—but they became superior
draft animals only with the adoption of an eYcient harness
and iron horseshoes, and their widespread use in tradi-
tional agriculture came only when changes in cropping
patterns provided enough concentrate feed.
Virtually all fuel in preindustrial societies came from
wood, charcoal, and straw. For household cooking and
heating, these fuels were burned ineYciently in a variety
of fireplaces; enclosed stoves with chimneys are a surpris-
ingly late innovation. Because of its high energy density,
charcoal was the preferred fuel for smelting and pro-
cessing metals, mainly copper, iron, and steel, and for fir-
ing bricks.
Our ancestors spent more than nine-tenths of their exis-
tence as hunters and gatherers in activities that required
many physical and mental adaptations and were also indis-
pensable for the emergence of social complexity. But only
in some coastal communities, tapping rich seasonal migra-
tions of ocean fish and mammals, could foraging support
high population densities and lead to a sedentary exis-
tence. On grasslands and in forests population densities of
roaming foragers were hardly higher than those of their
primate ancestors.
As their numbers rose, most foragers had to turn to
an increasingly sedentary way of cropping. These agricul-
tural practices began with shifting cultivation. In this
least energy-intensive mode of crop production the culti-
vation of several crops of tubers, grains, or fruits on a
patch of land cleared of natural vegetation (usually by fire)
alternated with often long periods of fallow.
A further rise in population densities brought a vari-
ety of traditional agricultures. Throughout the Old
World human groups shared domestication of animals, re-
liance on plowing, and the cultivation of staple cereal and
4
PREINDUSTRIAL SOCIETIES
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Most preindustrial labor was done by muscular exer-
tions of people and animals. More powerful sources of
kinetic energy—waterwheels and windmills—were in-
vented only after millennia of settled societies, and in most
such societies they made only marginal contributions. The
capacities of these mechanical prime movers, used for
many food processing and manufacturing tasks and also in
raising water, grew only slowly.
Improvements in the typical performance of sailships
were also very slow. Fundamental breakthrough came only
at the beginning of the early modern era. At that time the
combination of more maneuverable vessels with more ac-
curate guns (made possible by advances in the smelting
of copper and iron and by the invention of gunpowder)
produced an energy converter of unprecedented speed,
range, and destructive power that helped to usher a new
era of world history.
Hunters and Gatherers
Only an uninformed view would not perceive tens of
thousands of years of hominid foraging as a prolonged
prelude to a truly sapient existence in increasingly complex
civilizations. To continue the musical analogy, it was very
much like acquiring a large ensemble of specialized instru-
ments, fine-tuning them, and getting them ready to play
ever more intricate scores. Development of all of the key
characteristics distinguishing humans from other pri-
mates—bipedality, manual dexterity, elaborate tool mak-
ing, intergenerational transfer of technical skills, and
higher encephalization—was fostered by our evolution
from simple foragers to sophisticated hunters and incipi-
ent plant cultivators.
The earliest foragers were almost certainly opportu-
nistic scavengers, taking advantage of partially eaten herbi-
vore carcasses left behind by large predators—or at least
breaking the bones to extract the nutritious marrow. They
were obviously omnivorous, collecting and killing scores
of diVerent edibles, but a small number of foods was usu-
ally dominant. Large roots—easily found by associated
leaves or stalks and dug out quickly with the help of
pointed sticks—provided the highest (up to fortyfold) net
energy returns in gathering. But unlike grains, which
were also easy to collect and had higher energy content,
they were low in protein. High returns in collecting large
seeds and nuts were reduced by often considerable energy
expenditures in their processing.
Typical gathering of a wide variety of plant foods re-
turned at least ten to fifteen times the invested energy, ra-
tios similar to killing large mammals—while hunting
smaller animals yielded much smaller energy returns. For-
aging was especially unrewarding in tropical forests where
edible fruits and seeds are a very small share of total plant
mass and are mostly inaccessible in high canopies. And
because most tropical mammalian herbivores are arbo-
real, their hunting also yielded low energy returns. This
explains why there is no unambiguous ethnographic ac-
counts of tropical foragers who would not engage in some
plant cultivation.
In contrast, grasslands provided excellent foraging
environment. Grass seeds and starchy roots were easy to
collect, and there were many large herbivores. Cooperative
hunting of large ungulates—much more rewarding than
solitary pursuits—clearly made lasting contributions to
106
CHAPTER 4
Comparison of the oldest Oldowan tools with larger
Acheulean hand axes used to butcher animals.
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two thousand-fold net energy return, perhaps the highest
documented foraging gain. Much lower, but still very
comfortable, ratios were obtained by killing seals or catch-
ing migrating salmon. Seasonal abundance of such foods
could be also easily preserved by drying or smoking and
stored for later use. Large-scale food storage helped to sta-
bilize populations at higher densities: maritime foragers
could cease roaming and could live in fairly large, perma-
nent settlements with social stratification, elaborate ritu-
als, and long-distance trade.
Except for some maritime cultures, foraging societies
could not attain population densities needed for func-
tional and social diversification. The least hospitable envi-
ronments (tundras, boreal forests) supported population
densities of just 1 person/km2, while the most suitable
habitats (tropical and temperate grasslands) could carry
from ten to a hundred times more people. Because of
diVerences in phytomass storage, accessibility and edibility
of plant parts, and sizes and habits of hunted animals these
large density variations had no simple correlations with
total photosynthesis or biodiversity of habitats.
human socialization. Many large mammals could be killed
by skilfully driving them into confined runs and capturing
them in pens or natural traps, or by stampeding them
over cliVs.
But simple energy ratios favoring the killing of bison
over the snaring of hares does not capture the desired
quality of hunted food. Foraging diets were often low in
lipids, and inland hunters could satisfy the apparently uni-
versal craving to eat filling fat, rather than just lean meat,
only by killing larger fatty mammals. This is why the Afri-
can hunters, exploiting the unique human capacity for
long-distance running, were willing to chase big ante-
lopes to exhaustion; this is why their counterparts in bo-
real Europe were willing to face huge woolly mammoth
with their simple spears; or why North American Indians
invested so much eVort into driving bisons across preci-
pices: energy return on their labor investment was eating
food uncommonly filling with lipids.
Maritime hunters could get similar rewards with usu-
ally much less exertion. Killing of migrating baleen whales
by the Northwestern Alaskan Inuit provided more than a
107
PREINDUSTRIAL SOCIETIES
G/wi
boreal or subarctic
foraging environments
arid
tropical
Punan
Aranda
Dorobo
Cheyenne
huntingfishing
gathering
Dobe
Cree
70
50
30
10
90
70
50
10
30
90
70
50
30
10
90
Chenchu
Siriono
SemangPaiute
Andaman
Crow
Vedda
Ona
Montagnais
Mbuti
AetaKwakiutl
Klamath
Nootka
Makah
Aleut
Twana Micmac
Nunamiut
Approximate contributions of gathering, hunting,
and fishing to typical diets of some foraging societies
surviving into the twentieth century.
Population density (people/km2)
Nunamiut
Aeta
Netsilik
Dobe
Cree
Punan
Siriono
G/wi
Mbuti
Vedda
Kwakiutl
Nootka
Makah
Di
st
an
ce
t
ra
ve
lle
d
(k
m
/y
ea
r)
10 3
10 2
10 1
10 -3 10 -2 10 -1 10 0
Relationship between population density and annual travel in
foraging societies: Maritime cultures could be least mobile.
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Although some foraging societies had to spend just a
few hours a day to enjoy abundant food supply, other had
to cope with recurrent hardships intensified by seasonal
food shortages leading to high infant mortalities (and to
infanticide) and to often devastating famines. The idea of
foraging existence as the original aZuent society is clearly
an impermissible generalization.
Overall energy returns of crop cultivation were com-
monly lower than those for many kinds of foraging, and
that is why hunters and gatherers coexisted with settled
agricultural societies for hundreds, and sometimes even
for thousands, of years. But even extensive cultivation
could support higher population densities and assure a
more reliable food supply than that enjoyed by most
foraging societies. The fastest transition to permanent
cropping happened on fertile floodplains, but elsewhere
agriculture began, and continued for often very long
periods, as shifting cultivation.
This practice extended from rainy tropics to the sub-
arctic forests, and it encompassed a wide variety of species
108
CHAPTER 4
Burning of forest phytomass, the first
step in creating temporary fields.
modern farming
traditional farming
shifting farming
pastoralism
foraging
Po
pu
la
ti
on
d
en
si
ty
(p
eo
pl
e/
km
2 )
10 3
10 2
10 1
10 0
10-1
10 -2
Shifting cultivation could support population densities two
orders of magnitude higher than foraging—but an order of
magnitude lower than traditional farming.
Shifting Cultivation
Adoption of plant cultivation, and in most cultures also of
associated domestication of animals, was a multifocal and
gradual process stimulated by population growth beyond
the densities supportable by foraging and by environmen-
tal changes (such as a drier climate or elimination of pre-
viously abundant prey) reducing food supply that hunters
and gatherers could get by foraging. Diminishing energy
returns in foraging favored more regular reliance on incip-
ient cultivation begun with the deliberate planting of tu-
bers or scattering of seeds that was practiced by many
gatherers.Domestication of wild grains and cattle oVered
a supply of high-quality nutrients.
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ping. Net energy returns for grains, be they tropical
(dryland Asian rices), subtropical (African millets), or tem-
perate (European rye) ranged mostly between ten and fif-
teen. Less labor was needed for corn (its energy returns
were commonly more than twentyfold) and for tropical
tubers, legumes, and bananas (the best energy returns
ranged between forty and seventy). Ancient Mesoamerica,
with staples of corn, beans, and squash, achieved some of
the highest food production eYciencies, but even less
eYcient shifting cultivation could support population
densities ten times higher than those of prosperous hunt-
ers and gatherers. Minima were about 0.2 people per
hectare in Eastern North America (corn gardening), max-
ima surpassed 0.6 people per hectare in Southeast Asia
(upland rice and roots). High energy returns sustained
shifting cultivation in parts of Asia, Africa, and Latin
America into the twentieth century. Higher population
densities and shorter regeneration cycles have been the
main reasons for its recent decline.
Traditional Agricultures
DiVerences in climate, soils, crops and in specific farming
practices created a great variety of traditional agricul-
tures—but physical imperatives of field cultivation dic-
tated a recurrent pattern of labor. Throughout the Old
World the sequence begun with plowing and harrowing
which prepared loosened, weed-free, well-aerated, and
leveled soil ready for sowing (mostly by hand). Plow de-
signs progressed from the simplest symmetrical scratch
plows, which created merely a shallow furrow for seeds,
to asymmetrical moldboard plows—first just straight
pieces of wood, later with curved metal plowshares—
which turned soil over, buried the cut weeds, and elimi-
nated the need for crossplowing. Harvesting was done,
slowly, by sickles, later by more eYcient scythes (the first
successful mechanical reapers were introduced only after
1830).
and local peculiarities. But everywhere it alternated be-
tween short periods of cropping (commonly just one sea-
son, rarely more than three years) and long spans of fallow
(sometimes up to twenty-five to thirty years, more com-
monly at least a decade). The cropping cycle began with
often only partial removal of natural phytomass. In forests
and shrublands this was done by a combination of felling,
slashing, and burning; in grasslands just by setting fires.
Nearly all nitrogen was lost in combustion, but mineral
nutrients helped to produce at least one or two fairly
good crops.
Cultivated species included cereal and leguminous
grains, tubers (sweet potatoes, cassava, yams), vegetables,
fruits, fibers, and medicinal plants. Few staples provided
most of the food nutrients, but the total number of
planted species was rarely less than a dozen, and in warmer
environments it often surpassed two scores. Cultivation
was done commonly in jumbled, gardenlike arrange-
ments, with high degrees of interplanting and intercrop-
109
PREINDUSTRIAL SOCIETIES
Roots have been dominant staples in tropical shifting cultivation.
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