The first farmers: Theories and Old World evidence
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Copyright Bruce Owen 2000
Why are archaeologists so obsessed with agriculture?
It is a recent change in the way humans have lived for most of their existence
starting roughly 11,000 years ago (9000 BC)
and even that only in a few places; it took a long time to be adopted in many other places
compare a maximum of 11,000 years of agriculture almost 30,000 years of the Upper Paleolithic (40,000 BP to 13,000 BP), not to mention the Middle Paleolithic
If you count the existence of "humans" since the appearance of Homo erectus, about 99.4% of the time that we have been on this planet, humans were foragers; only during the last 0.6% of our existence have some humans tried a different source of subsistence.
Even if you include only Homo sapiens, starting around 100,000 BP, fully 90% of our evolutionary history was as foragers.
so: farming is a very recent aberration for the human race.
we evolved biologically as foragers
that includes not only our bodies, but also our capacity for thought and planning
our propensities for social relations
and our emotions
More complex forms of society, including larger chiefdoms, states, and empires, only appeared after people started farming
in all the time that people were foragers, they never developed more complex, larger-scale societies
so there must be some connection between agriculture and complex society
Further evidence that agriculture was a necessary condition for the development of complex society:
in every known case in which a complex society arose on its own, without influence from one that already existed, it was based on agriculture
no large-scale, complex societies ever developed among foragers
nor among pastoralists (herders), except when they were part of a larger system that also included farmers who already had a complex society
there may be some exceptional cases in which maritime people (based on fishing and shellfish collecting) developed large, complex societies
but even these are debatable as to their "complexity" and whether or not agriculture also played a role
Some key ideas about agriculture
Agriculture
= activities that artificially increase plant food yields.
from simply burning grassland to encourage the growth of seed-bearing grasses (this is often not even considered agriculture)
or scattering seeds in naturally wet areas
to plowing, sowing, weeding, irrigating, etc.
Domestication
= genetic modification from the wild form to one that is more useful to people
domestication of plants
the wild plant evolves under human selection, intentional or not
later we will look more specifically at how wheat evolved under human selection
to the point that some actually become dependent on humans for planting (corn [maize] is an extreme case)
domestication of animals
may start with hunters who depend on a limited number of animal herds selecting which animals to kill in order to best maintain the herd
initially they would prefer to kill adult males and leave the young and females; later they might start intentionally leaving the "best" animals to reproduce
this "herd management" causes evolution and eventually domestication
Neolithic
: two meanings
1. a stone tool technology that emphasizes grinding, rather than flaking (as in the Paleolithic)
This results in smoother, stronger, longer-lasting edges (although not as sharp)
good for axes needed to cut trees to clear farmland
2. more importantly for us, the period in which agriculture comes into use and is the main source of food
so called because in many places, ground-stone tools come into use at about the same time as agriculture becomes important
so they serve as a convenient short-hand marker and term for early agricultural periods around the globe
Agriculture provides more food per unit area of land, compared to foraging
That is, you get more food per acre by farming it than by collecting the wild foods on it
This allows more people to live in a given area
That is, it allows a higher density of people
Of course, it takes more labor to farm an acre of land than to collect the wild foods that are naturally there
This process of putting in more labor per acre to get more product per acre out is called "intensification"
agriculture is more "intensive" than foraging
in that it produces food more per acre, but requires more labor per acre to do so
agricultural practices themselves can be more or less "intensive"
just scattering seeds or diverting floodwaters to wet some land does not take much labor, and is not a very "intensive" form of agriculture
building and maintaining canals to irrigate the fields is more "intensive" than just depending on rainfall
because they are getting more crops per acre
at the cost of building and maintaining the canals
Is farming a good deal?
that is, if it takes twice as much labor to farm an acre, do you get twice as much food from that acre in return?
this question has been studied in numerous real, specific cases of foragers and farmers
most notably by Esther Boserup
the surprising, empirical answer is, in most cases: no!
In fact, agriculture usually requires more labor per unit of food produced than does foraging
That is, a farming family has to work more hours per year to provide its own food than a foraging family does
That is why modern (or recent) foragers like the !Kung prefer to forage rather than to farm
they were quite aware of the farmers who lived near them and the methods they used
but they could get the food they needed with less work by foraging
When Richard Lee asked the !Kung why they don't farm, one famous reply was "Why should we farm when there are so many mongongo nuts?"
but
this only works as long as there aren't too many people for the wild resources to support
when there is a lot of land per person, that is, a very low density of people
if there isn't enough land (or there are too many people), foraging just can't provide enough food
and farming (or herding animals) becomes the only alternative to hunger
This is counterintuitive to many people
we tend to assume that foragers live a hard life and are constantly on the brink of starvation
while we tend to assume that farmers have a comparatively stable, easy source of food
In fact, farmers generally work harder and have less free time than foragers.
Agriculture is a devil's bargain
You get more food per acre
But you get less food per hour of work
In economic terms, agriculture increases the returns to land, but decreases the returns to labor
In a given area, agriculture can produce more food overall, and so feed more people
But they have to work harder than before to survive
There is an old idea that when people switched from foraging to farming, they escaped the pressures of a precarious existence and suddenly "had the time" to develop "civilized" features like art, literature, science, and technology
but now you know that it was quite the reverse
farmers have less free time than foragers
so we need some more sophisticated explanation for the development of complex society
Agriculture allows people settle in one place (become sedentary), and creates reasons for them to do so
It allows them to settle because
agriculture can provide enough food in a limited area that the food is not exhausted before the next season replenishes it
so people don't have to move in order to get food
It encourages them to settle because
fields must be tilled, weeded, irrigated, harvested, etc., which requires people to be there at many different times during the year
harvests produce a lot of food at one time, which has to be stored for use over a longer period
staying near the stored food is easier than carrying it around
Under some circumstances, foragers can be sedentary or semi-sedentary, too
but this is not common, and usually involves extreme specialization on one or a few very productive wild resources in specially favored places
we will see that these special circumstances may have been keys to the initial development of agriculture in certain favored locations
agriculture, on the other hand, allows and encourages people to become sedentary in many different environments
Agriculture and sedentism tend to lead to population growth
They tend to increase fertility for biological reasons
Increased carbohydrate consumption from agricultural crops may keep body fat levels high enough to increase fertility (or at least not periodically reduce it)
foragers often get very lean during the season of scarcity (it varies in different regions), which reduces female fertility
this is an effect familiar to female runners and dancers
Less mobile mothers have fewer spontaneous abortions
Since the mother does not have to carry her infant around while foraging, sedentism makes it practical for a woman to have more than one infant at a time, allowing larger families
mothers are not forced to take measures to prevent having another infant while a previous one is still small
such as abstinence rules, contraceptive measures, induced abortions, or infanticide, all of which were practiced by at least some foragers
Less mobile mothers may wean children sooner; this shortens the period of reduced fertility due to lactation
They may wean earlier simply because the child is not always right in their arms or on their back, as it is for mobile foragers. This has the unintentional result of increasing fertility
They also may wean earlier with the intention of having more children for farm labor; many foragers are aware of the fertility-inhibiting effect of lactation
Agriculture also provides economic incentives to have more children
Farming creates a greater demand for labor, that is, kids to help with the work
Sedentism reduces the cost of having children, since the mother does not have to carry them around as much
So farmers tend to have large families, and the population tends to grow
Population growth makes the shift to agriculture almost irreversible
People shift to agriculture
Population grows beyond the capacity of the land to support by foraging
the people are locked in to higher yields and higher population density of agriculture
they can't give up farming without causing hardship or starvation
So the shift to farming is to some extent a one-way change
there is no going back without unacceptable disaster
Agriculture and sedentism have surprising effects on nutrition and health
agriculture, especially in its early stages, often focuses on one or a small number of the most productive crops
this results in a less varied diet than foragers eat
and often poorer nutrition overall
more labor leads to more arthritis and other wear-and-tear ailments
living in permanent villages creates new problems of sanitation (waste disposal, insect infestation, etc.) that encourage disease
living in larger groups also aids the spread of epidemic diseases
overall, settled agricultural lifestyles typically increase biological stress on people
and often decrease lifespan
we already saw that agriculture and sedentism may increase fertility
so more children are produced, but they have a shorter life expectancy
in theory, these two trends could cancel each other out
but the observed pattern is that in most cases, the net effect is a population increase
Agriculture and sedentism have cultural effects, too:
Sedentism allows accumulation of material goods: storage of goods and food
foragers are mobile, so they can never accumulate many goods
so no forager can be much more wealthy than another
sedentary people are free to accumulate great piles of stuff
and some will accumulate more than others, for many different reasons
so sedentism allows the differentiation of people into richer and poorer
sedentism makes economic stratification possible
accumulation is not limited to a single generation, either; land and accumulated goods can be inherited, leading to wealthy, even aristocratic families
this does not occur among foragers, where each individual essentially starts fresh in building his or her status in society
Agriculture and sedentism allow the production and storage of surplus: food or other goods beyond the needs of the producer
surplus production is possible for at least some foragers, but transportation and storage problems make it difficult to take advantage of, and uncommon
surplus production makes it possible to support craftspeople and other specialists who do not produce all (or any) of their own food
like specialized potters, toolmakers, blacksmiths, doctors, administrators, soldiers, etc.
people who create apparently non-productive things like pyramids, palaces, temples, armies, costly artwork, etc.
why would anyone go to the trouble of producing a surplus?
why work harder than necessary, to produce more than you need?
to satisfy increasing wants
because you are obligated or forced to
the existence of surplus and people who don't produce all their own food creates a whole new arena for social arrangements that may become very complex. Consider:
does each farming family store and control its own surplus, or does some or all of it get stored in shared, communal, or other arrangements?
if there is pooled surplus, whoever administers it has real power
who puts in to the common pool?
who gets a share of the pooled surplus?
Agriculture allows larger groups to live together (hamlets and towns, vs. mobile bands)
people have to interact with a larger number of others
the kinship system becomes inadequate to structure interactions
since you can't know and keep track of so many relationships
so people start using other criteria to determine how to interact with the people they encounter
such as social status, class, rank
this is the beginning of more complex social organization
greater likelihood of conflicts
because more people are interacting with each other
because people can't defuse problems by simply moving away easily
encourages the development of institutions for conflict resolution (respected authorities, courts, etc.)
Settled people with goods are easier to raid, threaten, conquer, control, tax
unlike foragers, settled agriculturalists have land and goods that people may want to take by force
so raids or warfare become possible
and farmers may need to defend themselves
settled farmers are easier to coerce, because they are committed to stay in one place and have goods that can be taken from them
agricultural surplus makes it possible to support some people to carry out such coercion (a chief's thugs, armies, the IRS, etc.)
this vulnerability, surplus, and accumulation of wealth help make power hierarchies (complex society) possible
Agriculture and sedentism make these changes, many of which are steps towards complex society, possible.
But agriculture and/or sedentism do not cause society to become more complex; they just make that change possible, while among foragers it was not.
Some foragers specializing in unusually rich resources (like salmon on the northwest coast of the US, or acorns in California) were sedentary and lived in relatively large villages, even without agriculture
Yet none of these developed states or "civilizations"
Besides, settled farmers were around for thousands of years before larger towns and complex societies emerged
So sedentism, and even agriculture, are apparently necessary steps, but not sufficient ones, for the development of social complexity
What we want to know about the origins of agriculture
Basic facts
Where and when agriculture began
With what crops
Explanation: How and why did people start farming?
Why did agriculture seem like a good deal at the time?
Why did people start farming at certain places and times, and not others?
Basically, "Why farm when there are so many mongongo nuts?"
Invention vs. adoption
foragers are extremely knowledgeable about their environment
they understand how plants respond to water, regrow in burnt areas, how seeds work, how animal reproduce
the question is not so much "how and when did they figure out that they could manipulate plants", since that is probably an easy insight that many foragers would have had
but rather "why did they actually start manipulating plants on a sufficient scale to provide more than a trivial part of their diet and cause the biological changes of domestication?"
What actually happened?
Places, dates, crops where agriculture may have started relatively independently
Fertile crescent, esp. the Levant, in Southwest Asia 9000 - 8000 BC
wheat, barley, peas, lentils
sheep, goats, cattle, pigs
North-central China by 6000 BC
millet
Southern China and southeast Asia before 5000 BC
rice
probably also root crops, maybe even earlier
Sub-saharan Africa after 2000 BC
rice, sorghum, millet
Mexico before 5000 BC
gourds, squash, avocados, peppers, beans, corn
may not have needed much meat
turkeys and dogs domesticated
Peruvian highlands by 3000 BC at least
gourds, tomatoes, beans, potatoes
llama, alpaca, guinea pig
New Guinea maybe by 6000 BC, or earlier
digging stick in field dated to 6000 BC...
probably for yams
Eastern North America by 1000 BC
marsh elder, sunflower, goosefoot
maize much later, an introduction from the south
Farming started at different times in different places, with different crops, probably through somewhat different processes
The transition was often a very gradual increase in dependence on plants that were encouraged by sowing, simple irrigation, burning off competing grasses, etc.
so it is hard to pick a specific date when farming "started" or became important
Depending on where you draw the lines, most of the world's major agricultural traditions began
in a period as broad as from about 10,000 BC to about 3000 BC
or a period as short as from about 8500 BC to 6500 BC
of course, many groups did not start farming until later, or did not become fully dependent upon farming
Yet still relatively speaking at about the same time in human existence.
that is, humans existed for at least a hundred thousand years, then adopted agriculture around the world in "just" a few thousand years
What was special about this time that many different cultures began farming then?
Homo sapiens
evolved and populated the world during the Pleistocene (ice ages)
The Pleistocene tapered off and the climate warmed, ice retreated, sea level rose, wild plant and animal communities changed...
within a few thousand years, humans were farming in many places around the world
in the broad scheme of things, these independent inventions of agriculture happened in the same post-Pleistocene setting and time frame, reflecting the same general processes
they presumably had something to do with the climate changes
and possibly with the gradually rising populations of humans around the world
at a more detailed level, thousands of years separated the adoption of agriculture in different regions
and each case happened in ways specific to the environment and cultures of the area
A suggested process of domestication of wheat (other grains would have been similar)
wild wheat
seeds have brittle rachis [RAY-kis] (attachment to the stem), so they fall off easily
seeds are narrow and have a rounded point that lets them penetrate cracks in the ground
humans started collecting wheat, probably by pushing a basket up to the heads of wheat and giving them a tap to make the ripe seeds fall into the basket
those seeds that happened to have a more brittle rachis were more easily collected, because they fell off the stems more easily. Plants that happened to have a slightly tougher rachis lost fewer seeds to the harvesters. These seeds that were NOT harvested were the ones that remained to naturally sow the next generation of plants
this process strongly selected for plants with a tough rachis, gradually producing a kind of wheat more like the domesticated form, in which the seeds stay on the head and have to be removed by threshing
since an increasing fraction of the seeds did not fall off easily when ripe, the wheat became less effective at sowing itself naturally
the natural wheat stands became less and less productive
people started "helping" the wheat by sowing part of the harvest
eventually they started intentionally selecting seeds to sow that had the desired qualities: fat, large grains
similar processes are supposed to have happened with other crops, especially cereals
The classic "western" agricultural complex, starting in southwest Asia
crops and animals:
Wheat and barley
plus lentils, peas, and other minor crops
Sheep and goats, cattle and pigs
Agriculture arose in and spread throughout Southwest Asia
the very first agriculture in the world, as far as we know, and the best studied
Southwest Asia = Near East
Mesopotamia, the Levant, Anatolia [Turkey]; Egypt; Europe; sometimes includes the Indus region
huge: the size of the continental US
climate and environment like New Mexico, Arizona, Utah, Colorado
driest to the south, wettest to the north
Mesopotamia too dry to farm without irrigation
"fertile crescent" along base of mountains where rainfall is sufficient for agriculture
Levant (east shore of Mediterranean Sea)
Israel, Lebanon, western Jordan, western Syria
location of wild ancestors of domesticated wheat, barley, legumes; sheep, goats, pigs, cattle
environmental changes that formed the background to domestication
as the Pleistocene ended, warming began around 13,000 BC (continued to about 3000 BC)
more rainfall from about 18,000 BC helped forest expand until about 7000 BC, when rising temperature canceled out rainfall gains by evaporating more of the moisture
so after 7000 BC, the forest started to shrink again
foragers' diets adjusted as forest expanded (18,000 - 7,000 BC)
reduced focus on hunting, reduced of variety of plant foods, increased specialization on certain highly productive plants
especially focussing on wild grains
shown by grinding equipment
sickle blades
storage pits
roasting areas (getting the husk off the seeds)
Natufian Period 10,000 - 8,000 BC
period just before the adoption of agriculture
somewhat wetter and greener environment than today
such rich resources that foragers could have relatively permanent settlements
that is, they could forage in one area without exhausting the resources around them before the next season came to replenish them
no need to farm
these sedentary "intensive" foragers were the people who then developed agriculture
number of sites increased, implying that the population was rising
Agriculture apparently first appeared in the Levant, lapping into the Euphrates valley
When: the Neolithic period, end of Natufian and into the Neolithic
c. 8500 BC at Abu Hureyra, cereals quickly became important (in just a few centuries?), although wild foods remained important too for 2500 years
c. 7000 BC at Abu Hureyra, there was another quick (100 years?) switch from hunted gazelles to domesticated sheep and goats, in addition to the cereals, lentils, peas
two scenarios "explaining" increased sedentism and focus on cereals, leading to incipient agriculture:
drying model
as climate dried, mobile people would tend to stay closer to water sources during at least part of the year
they would encourage plants in the area to produce, so they would have food to gather
seasonality model
as seasonality increased (somewhat speculatively), people might deal with seasonal scarcity by gathering extra quantities of storable foods (like grains) and storing them
this would tie them down, at least in the periods when they had to eat the stored foods
the need to harvest a lot might lead to encouraging increased production
In these models, sedentism and storage come before agriculture and domestication
this agrees with the archaeological evidence
this process could only happen in a place that was so rich in wild cereals that sedentary life with significant storage could develop without agriculture
but once the cereals were domesticated and agricultural practices were developed, agriculture could spread to other areas and have the effects discussed earlier
Domestication of animals, adoption of herding practices
how to tell hunting from herding using archaeological bone remains
by age and sex distributions
if hunted:
closer to a random sample of ages and sexes
more adults, both sexes
if herded:
excess representation of young males
since few adult males are needed to maintain the herd
but all adult females are needed for propagation and milk
difficult to tell "herding" from "wild herd management"
what happened in Southwest Asia
up to 10,000 BP, all animals are found in "hunted" age pattern
then, sheep and/or goats start turning up in "herded" age pattern
An example Natufian site: 'Ain Mallaha: 11,000-9000 BC
on a hillside, by a spring
overlooking swampy bottom of upper Jordan valley
three successive permanent villages
each with several round houses (3-8 m diameter)
close together, around a central open space with storage pits
at 11,000 - 9,000 BC, one of the first settled villages known anywhere
about 2000 square meters (1/5 hectare) (about 45 x 45 m)
3 of these sites would fit in the bacon-and-eggs plaza
population estimated around 200 - 300 people
sounds very high to me for such a small area and just a few houses
large round houses
stone lower walls up to 1 m tall
probably with conical roofs supported by a center post
stone-lined hearths (fire pits) and stone-lined storage bins inside
mortars and querns (grinding stones) used to grind grain found on or set into floors
An example early farming village: 'Ain Ghazal 7000 - 6000 BC
Neolithic - but mostly later than Abu Hureyra and Jericho PPNA
subsistence
farming wheat, barley, peas, beans
sickles
hunting, maybe starting to herd goats and cattle
large (12 ha) domestic site
twice the size of contemporary sites
rectangular houses
rubble-filled two-faced stone wall bases with pole, reed, and mud upper parts
floor and lower walls plastered
some walls painted with designs
benches along the walls
central hearth
on leveled terraces with stone retaining walls
many houses were significantly remodeled over time
implies long period of use as family membership changed
burials in the floor
almost 20% over 50 years old!
some headless
four skulls in a pit
faces reconstructed with plaster
tar in eye sockets
other sites have inset shells for eyes
one skull in another pit
scraped with a knife
coated with red ochre
all this reflects practices at other neolithic sites in southwest Asia
cache of 84 flint blades in a hole under a house floor
what does this mean?
accumulation of wealth?
specialized production for exchange?
also seen in other neolithic sites, like Çatal Hüyük
beads and pendants
turquoise, carnelian, amber, "greenstone", shell
ritual
ceramic figurines, human and animal
two caches of large figurines
plaster on framework of tied sticks and reeds
represent individuals?
indicate ancestor worship?
mostly, but not all, male
one has 6 toes
"accounting" tokens
The spread of agriculture
the development and adoption of the various features of agricultural life in different parts of the world did not happen simultaneously, or even in the same order in every case
sedentism
plant domestication
animal domestication
ceramics
nor in similar environments
so it was probably a highly variable process, with different reasons and mechanisms, each specific to its own area
yet all coming to more or less the same result eventually...
This transition to farming made it possible for people to live in towns, an important innovation with significant social effects