What Caused the Decline of the Mayan Civilization?

The collapse of the Mayan

civilization at the end of the so-called

classic period, between 200 and 900,

is a persistent archaeological mystery.

The classical Maya were the most

advanced of the pre-Columbian

civilizations, anchored by a collection of

city-states in the lowlands of modern-day

Guatemala, Belize, and the Yucatan

Peninsula. But around 700, these citystates

began an inexorable decline that

ended in their total abandonment. While

the independent Maya survived until the

Spanish conquest in the late 17th century,

the postclassical Maya were a less urban

and populous civilization.

Archaeologists have posited a number

of theories explaining the decline of the

classical Maya, from foreign invasion to

disease epidemic to a collapse in trade with

neighboring cultures, but one of the oldest

and most persistent theories centers on

drought. The Yucatan Peninsula and Petén

Basin were already particularly susceptible

to variability in rainfall—the soil is thin

and sandy, and a regular seasonal drought

complicates agricultural productivity

Though the Maya had solved this problem

through advances in fertilization and

irrigation, studies of soil and stalagmites in

the region indicate a decline in rainfall of

between 25 and 40 percent in the late

classical period. For a culture living off an

already fickle water supply, this

megadrought may have been too much for

even advanced Mayan hydrological

engineering to overcome.

Drought by itself, however, doesn’t

explain the fall in its entirety. It doesn’t

explain why the Maya didn’t return to the

classical cities after the climate righted

itself in the second millennium or why the

northern cities that ascended in the

aftermath never reached the heights of the

lowland city-states. Nor is it clear why the

drought occurred in the first place. It may

have been cyclical, but some researchers

believe that the Maya instigated the

drought by clear-cutting rain forest, cutting

short the water cycle that topped off the

reservoirs that slaked their thirst during the

dry periods.

Almost as mysterious as the decline of

the Maya is the fact that the classic Mayan

civilization took root where it did. Dense,

urban settlements dependent on agriculture

have not historically thrived in jungle

climates rooted in limestone soil. That the

Maya flourished there at all is testament to

the ingenuity of their civilization.

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