Collapse: How Societies Choose to Fail or Succeed (31 page)

peoples with their horses, oxen, donkeys, and camels, the Maya had no
animal-powered transport or plows. All overland transport for the Maya
went on the backs of human porters. But if you send out a porter carrying a load of corn to accompany an army into the field, some of that load of corn is required to feed the porter himself on the trip out, and some more to feed
him on the trip back, leaving only a fraction of the load available to feed the
army. The longer the trip, the less of the load is left over from the porter's
own requirements. Beyond a march of a few days to a week, it becomes un
economical to send porters carrying corn to provision armies or markets.
Thus, the modest productivity of Maya agriculture, and their lack of draft animals, severely limited the duration and distance possible for their mili
tary campaigns.

We are accustomed to thinking of military success as determined by
quality of weaponry, rather than by food supply. But a clear example of
how improvements in food supply may decisively increase military success
comes from the history of Maori New Zealand. The Maori are the Polyne
sian people who were the first to settle New Zealand. Traditionally, they fought frequent fierce wars against each other, but only against closely
neighboring tribes. Those wars were limited by the modest productivity of
their agriculture, whose staple crop was sweet potatoes. It was not possible
to grow enough sweet potatoes to feed an army in the field for a long time
or on distant marches. When Europeans arrived in New Zealand, they
brought potatoes, which beginning around 1815 considerably increased
Maori crop yields. Maori could now grow enough food to supply armies in the field for many weeks. The result was a 15-year period in Maori history,
from 1818 until 1833, when Maori tribes that had acquired potatoes and
guns from the English sent armies out on raids to attack tribes hundreds of miles away that had not yet acquired potatoes and guns. Thus, the potato's
productivity relieved previous limitations on Maori warfare, similar to
the limitations that low-productivity corn agriculture imposed on Maya
warfare.

Those food supply considerations may contribute to explaining why
Maya society remained politically divided among small kingdoms that were
perpetually at war with each other, and that never became unified into large
empires like the Aztec Empire of the Valley of Mexico (fed with the help of
their
chinampa
agriculture and other forms of intensification) or the Inca
Empire of the Andes (fed by more diverse crops carried by llamas over well-
built roads). Maya armies and bureaucracies remained small and unable to
mount lengthy campaigns over long distances. (Even much later, in 1848,

when the Maya revolted against their Mexican overlords and a Maya army seemed to be on the verge of victory, the army had to break off fighting and
go home to harvest another crop of corn.) Many Maya kingdoms held
populations of only up to 25,000 to 50,000 people, none over half a million,
within a radius of two or three days' walk from the king's palace. (The actual
numbers are again highly controversial among archaeologists.) From the
tops of the temples of some Maya kingdoms, it was possible to see the tem
ples of the nearest kingdom. Maya cities remained small (mostly less than
one square mile in area), without the large populations and big markets of
Teotihuacan and Tenochtitlan in the Valley of Mexico, or of Chan-Chan and
Cuzco in Peru, and without archaeological evidence of the royally managed
food storage and trade that characterized ancient Greece and Mesopotamia.

Now for a quick crash-course in Maya history. The Maya area is part of the
larger ancient Native American cultural region known as Mesoamerica,
which extended approximately from Central Mexico to Honduras and con
stituted (along with the Andes of South America) one of the two New World centers of innovation before European arrival. The Maya shared
much in common with other Mesoamerican societies not only in what they
possessed, but also in what they lacked. For example, surprisingly to
modern Westerners with expectations based on Old World civilizations, Mesoamerican societies lacked metal tools, pulleys and other machines,
wheels (except locally as toys), boats with sails, and domestic animals large
enough to carry loads or pull a plow. All of those great Maya temples were constructed by stone and wooden tools and by human muscle power alone.

Of the ingredients of Maya civilization, many were acquired by the Maya
from elsewhere in Mesoamerica. For instance, Mesoamerican agriculture,
cities, and writing first arose outside the Maya area itself, in valleys and
coastal lowlands to the west and southwest, where corn and beans and
squash were domesticated and became important dietary components by
3000
b.c.,
pottery arose around 2500
b.c.,
villages by 1500
b.c.,
cities among
the Olmecs by 1200
b.c.,
writing appeared among the Zapotecs in Oaxaca
around or after 600
b.c.,
and the first states arose around 300
b.c.
Two com
plementary calendars, a solar calendar of 365 days and a ritual calendar of
260 days, also arose outside the Maya area. Other elements of Maya civiliza
tion were either invented, perfected, or modified by the Maya themselves.

Within the Maya area, villages and pottery appeared around or after 1000
b.c.,
substantial buildings around 500
b.c.,
and writing around

400
b.c.
All preserved ancient Maya writing, constituting a total of about 15,000 inscriptions, is on stone and pottery and deals only with kings, nobles, and their conquests (Plate 13). There is not a single mention of com
moners. When Spaniards arrived, the Maya were still using bark paper coated with plaster to write books, of which the sole four that escaped
Bishop Landa's fires turned out to be treatises on astronomy and the calen
dar. The ancient Maya also had had such bark-paper books, often depicted
on their pottery, but only decayed remains of them have survived in tombs.

The famous Maya Long Count calendar begins on August 11,3114
b.c.
—
just as our own calendar begins on January 1 of the first year of the Chris
tian era. We know the significance to us of that day-zero of our calendar: it's
the supposed beginning of the year in which Christ was born. Presumably
the Maya also attached some significance to their own day zero, but we
don't know what it was. The first preserved Long Count date is only
a.d.
197
for a monument in the Maya area and 36
b.c.
outside the Maya area, indi
cating that the Long Count calendar's day-zero was backdated to August 11,
3114
b.c.
long after the facts; there was no writing anywhere in the New World then, nor would there be for 2,500 years after that date.

Our calendar is divided into units of days, weeks, months, years, de
cades, centuries, and millennia: for example, the date of February 19, 2003,
on which I wrote the first draft of this paragraph, means the 19th day of the
second month in the third year of the first decade of the first century of
the third millennium beginning with the birth of Christ. Similarly, the Maya
Long Count calendar named dates in units of days
(kin),
20 days
(uinal),
360 days
(tun),
7,200 days or approximately 20 years
(katunn),
and 144,000
days or approximately 400 years
(baktun).
All of Maya history falls into bak-
tuns 8,9, and 10.

The so-called Classic period of Maya civilization begins in baktun 8, around
a.d.
250, when evidence for the first kings and dynasties appears.
Among the glyphs (written signs) on Maya monuments, students of Maya writing recognized a few dozen, each of which was concentrated in its own
geographic area, and which are now considered to have had the approxi
mate meaning of dynasties or kingdoms. In addition to Maya kings having
their own name glyphs and palaces, many nobles also had their own inscriptions and palaces. In Maya society the king also functioned as high
priest carrying the responsibility to attend to astronomical and calendrical rituals, and thereby to bring rain and prosperity, which the king claimed to
have the supernatural power to deliver because of his asserted family rela
tionship to the gods. That is, there was a tacitly understood quid pro quo:

the reason why the peasants supported the luxurious lifestyle of the king
and his court, fed him corn and venison, and built his palaces was because
he had made implicit big promises to the peasants. As we shall see, kings got
into trouble with their peasants if a drought came, because that was tanta
mount to the breaking of a royal promise.

From
a.d.
250 onwards, the Maya population (as judged from the number of archaeologically attested house sites), the number of monuments and
buildings, and the number of Long Count dates on monuments and pot
tery increased almost exponentially, to reach peak numbers in the 8th cen
tury
a.d.
The largest monuments were erected towards the end of that
Classic period. Numbers of all three of those indicators of a complex society
declined throughout the 9th century, until the last known Long Count date
on any monument fell in baktun 10, in the year
a.d.
909. That decline of Maya population, architecture, and the Long Count calendar constitutes
what is known as the Classic Maya collapse.

As an example of the collapse, let's consider in more detail a small but
densely built city whose ruins now lie in western Honduras at a site known as Copan, and described in two recent books by archaeologist David Web
ster. For agricultural purposes the best land in the Copan area consists of
five pockets of flat land with fertile alluvial soil along a river valley, with a
tiny total area of only 10 square miles; the largest of those five pockets,
known as the Copan pocket, has an area of only 5 square miles. Much of the land around Copan consists of steep hills, and nearly half of the hill area has
a slope above 16% (approximately double the slope of the steepest grade
that you are likely to encounter on an American highway). Soil in the hills is
less fertile, more acidic, and poorer in phosphate than valley soil. Today,
corn yields from valley-bottom fields are two or three times those of fields
on hill slopes, which suffer rapid erosion and lose three-quarters of their
productivity within a decade of farming.

As judged by numbers of house sites, population growth in the Copan Valley rose steeply from the 5th century up to a peak estimated at around
27,000 people at
a.d.
750-900. Maya written history at Copan begins in the
year with a Long Count date corresponding to
a.d.
426, when later monu
ments record retrospectively that some person related to nobles at Tikal and
Teotihuacan arrived. Construction of royal monuments glorifying kings
was especially massive between
a.d.
650 and 750. After
a.d.
700, nobles other than kings also got into the act and began erecting their own palaces,

of which there were about twenty by the year
a.d.
800, when one of those
palaces is known to have consisted of 50 buildings with room for about 250
people. All of those nobles and their courts would have increased the bur
den that the king and his own court imposed on the peasants. The last big buildings at Copan were put up around
a.d.
800, and the last Long Count
date on an incomplete altar possibly bearing a king's name has the date of
a.d.
822.

Archaeological surveys of different types of habitats in the Copan Valley
show that they were occupied in a regular sequence. The first area farmed
was the large Copan pocket of valley bottomland, followed by occupation of
the other four bottomland pockets. During that time the human popula
tion was growing, but there was not yet occupation of the hills. Hence that
increased population must have been accommodated by intensifying production in the bottomland pockets by some combination of shorter fallow periods, double-cropping, and possibly some irrigation.

By the year
a.d.
650, people started to occupy the hill slopes, but those
hill sites were cultivated only for about a century. The percentage of Copan's
total population that was in the hills, rather than in the valleys, reached a
maximum of 41%, then declined until the population again became con
centrated in the valley pockets. What caused that pullback of population
from the hills? Excavation of the foundations of buildings in the valley floor
showed that they became covered with sediment during the 8th century,
meaning that the hill slopes were getting eroded and probably also leached
of nutrients. Those acidic infertile hill soils were being carried down into the valley and blanketing the more fertile valley soils, where they would
have reduced agricultural yields. This ancient quick abandonment of hillsides coincides with modern Maya experience that fields in the hills have
low fertility and that their soils become rapidly exhausted.

The reason for that erosion of the hillsides is clear: the forests that formerly covered them and protected their soils were being cut down. Dated pollen samples show that the pine forests originally covering the upper elevations of the hill slopes were eventually all cleared. Calculation suggests
that most of those felled pine trees were being burned for fuel, while the rest
were used for construction or for making plaster. At other Maya sites from the pre-Classic era, where the Maya went overboard in lavish use of thick
plaster on buildings, plaster production may have been a major cause of de
forestation. Besides causing sediment accumulation in the valleys and de
priving valley inhabitants of wood supplies, that deforestation may have
begun to cause a "man-made drought" in the valley bottom, because forests