plantings that included raised fi elds, terracing, canals, and
other irrigation systems. Th e raised fi elds and the canals were
constructed together; when the farmers dug out the canals,
they dumped the excess dirt onto the fi elds. Th is provided the
crops with a steady source of water and kept them away from
fl oods. Th e canals were a valuable food source, too; farmers
allowed wild turtles and fi sh to live in them and caught them
for meat. Th e Mayan priests maintained a complex calendar
that helped farmers keep track of the solar year. Th is calendar
told farmers when to plant their crops and when to harvest
them. It helped farmers plan their year so they could produce
the best possible crop.
Despite the fact that about 70 percent of the Mayan peo-
ple worked as farmers, Mayan farming never produced the
vast surpluses of grain that farmers in other areas achieved.
Th e damp climate made it diffi cult to store corn for more than
a year. Th e Maya had no domestic animals to help them plow
and instead had to do all their work by hand. Corn, the largest
crop, contains little protein, and the Mayan diet had few other
protein sources; as a result, most people were malnourished.
THE ANDES: QUINOA, POTATOES, LLAMAS, AND
GUINEA PIGS
People living in the Andes mountains of Peru developed their
own crops and domestic animals suited to their dry climate
and high altitude. Th ey cultivated two crops not grown else-
where, the potato and the grain quinoa. Th ey also domesti-
cated three animals: the llama, the alpaca, and the guinea pig.
Andean Americans ate many types of wild potatoes; there is
fossil evidence that people consumed wild potatoes as early
as 10,000 b.c.e. in Chile. Potatoes were domesticated between
2000 and 1200 b.c.e. Th e people of the Andes cultivated four
types of potatoes, one of which became the common potato
eaten all over the world today. People of the Andes also cul-
tivated the sweet potato. Archaeologists have found evidence
of domestic sweet potatoes dating to about 2000 b.c.e. Th e
sweet potato spread throughout the tropical portions of the
Americas and was a staple of the Caribbean diet by the time
Columbus arrived.
Quinoa is a grain that produces edible seeds. People be-
gan cu ltivating it from 2000 to 3000 b.c.e. It grows well in dr y
soils at high elevations and is quite hardy. Quinoa contains a
complete set of amino acids, which meant that people did not
have to combine it with a legume to get their necessary pro-
tein. It also contains fi ber, iron, magnesium, and phosphorus.
People boiled it like rice and ate it as a cereal.
Llamas and alpacas are four-legged animals related to
camels. Th eir wild ancestors, the guanaco (for the llama) and
the vicuña (for the alpaca), lived in herds with dominance
hierarchies, making them easy for humans to domesticate.
Th e process of domestication occurred gradually between
5000 and 2500 b.c.e. People used llamas and alpacas for both
wool and meat. Th ey also used llamas as pack animals on the
high mountain paths. Historians believe humans may have
domesticated llamas and quinoa simultaneously. Llamas eat
wild quinoa and pass the seeds onto the ground in their ma-
nure. When people began herding wild llamas and shutting
them in enclosures at night, the llamas’ manure would have
contained both seeds to grow quinoa and natural fertilizer
to help them germinate. Aft er a successful crop of quinoa
started growing, the farmers would move the llamas to an-
other corral. Th e quinoa grew inside the enclosure, safe from
grazing llamas.
Th e guinea pig was the third domesticated animal of
the Andes. Hunter-gatherers between 5500 and 10,000
b.c.e. consumed a great deal of wild guinea pig meat. Be-
tween 2500 and 5000 b.c.e. people began keeping guinea
pigs in their settlements to save the trouble of hunting them
and ensure a steady supply of meat. Guinea pigs were ideal
candidates for in-home domestication. Th ey reproduce rap-
idly and prolifi cally, they eat table scraps, and they like to
live in close quarters.SOUTHWESTERN UNITED STATES
Agriculture fi rst appeared in the southwestern region of the
present-day United States about 1000 b.c.e. People living in
caves in the mountains of New Mexico were growing corn
and squash around 800 to 1200 b.c.e. Beans arrived slightly
later, around 400 b.c.e. Th e tools and pots found with the
fossilized remains of corn and squash indicate that the cave
dwellers were not colonists from Mexico but instead local
hunter-gatherers who made occasional trips south of the
Rio Grande and returned home with seeds. Once agricul-
ture arrived in the region, southwestern Americans ad-
opted it quickly. Some historians believe these people had
already domesticated some local seed crops such as little
barley, amaranth, or chenopod, which prepared them for
larger-scale agriculture with corn. Scholars agree it was
certainly possible that foragers had discovered these local
seeds and begun growing them deliberately, but so far no
one has found changes in the forms of these local seeds that
would indicate domestication.
Th e people of the Southwest managed to create farming
practices that succeeded in a variety of environments and at
diff erent elevations, adapting their agriculture to local land-
scapes and wild animals. Early southwestern farmers lived
in circular houses in small settlements. Th ey kept their corn
in underground storage pits and spent much of their time
tending crops and grinding corn, which became an increas-
ingly important portion of their diet as the centuries went
by. Nevertheless, they continued to gather such wild plants
as cactus, mesquite, grasses, pinyon, and agave. Th ey hunted
mountain sheep, mule deer, and pronghorn antelope. Agri-
culture did not become the primary means of sustenance for
southwestern Americans until about the fi rst century c.e.
One rea son t h is t r a nsfor mat ion took so long wa s t he problem
of irrigation. Th e southwestern United States has little rain-
fall, and it was a constant challenge to keep crops alive in theagriculture: The Americas 47