448 THE INSCRIPTIONS AT COPAN. 
Perhaps the best known hypothesis seeking to explain the extinction of 
the Old Empire civilization is that suggested by Huntington, who believes 
a climatic change in the way of an increased annual rainfall, bringing disease 
and impossible living conditions in its wake, is the principal factor which led 
to the abandomnent of the southern cities. Huntington had previously 
advanced the general hypothesis of climatic change to account for similar 
archeological conditions, 7. ¢., the abandonment of regions formerly inten- 
sively occupied by man, in other parts of the world, notably in Turkestan,’ 
western China,” and Palestine,’ due in these regions to progressive drying-up 
of the water-supply, and later extended its application through the exact 
opposite of climatic conditions, 1. ¢., an excessive rainfall, to the Maya area. 
As applied to the Maya area‘ this hypothesis may be thus summarized: 
Due to a supposed shift of general climatic zones toward the Equator 
during the first millenium before Christ and persisting down to 450 after 
Christ, the present zone of subtropical dryness was pushed southward to the 
edge of the tropical zone of rains (7. ¢., the Maya area), especially in the 
winter. This change, postulated on data derived from the big trees of 
California (Sequoia washingtoniana) and involving there a period of increased 
rainfall, is supposed to have brought to the region of the Old Empire a more 
pronounced and longer dry season than it now enjoys, less precipitation 
during the rainy season, and a more stimulating climate, characterized by 
greater variability of temperature, particularly in the winter time. Under 
these latter climatic conditions Huntington believes much of the dense 
tropical forest which now covers this region and renders it so full of disease, 
particularly malaria, as noted above, would disappear and living conditions 
would be improved. In fine, he assumes that such favorable conditions 
actually did precede the rise of the Maya civilization during the first millen- 
nium before Christ,when they were probably developing their culture and 
graphic system to the point of recording it on stone, and that these condi- 
tions continued throughout the Early Period and the first half of the Middle 
Period, but with gradually increasing unfavorability, that is, increasing 
rainfall; until toward the close of the Middle Period, by 450 a. p., the cli- 
mate had deteriorated to such an extent that the rainfall was as heavy as it 
is to-day in this region, and was causing the Maya both trouble and concern. 
At this point, however, the pendulum swung the other way; the rainfall 
decreased, the climate improved, the forest grew less rapidly, it became 
easier to keep the cornfields from being smothered by a too luxuriant vege- 
tation—in short, living conditions which had been growing steadily worse 
for several centuries suddenly took a turn for the better; as Huntington 
says, the people took heart, and thus the Maya began the Great Period, the 
Golden Age of Maya sculpture, with increasingly favorable climatic condi- 
tions which continued for nearly a century until 540 a. p. 
1 Huntington, 1905. 2 [bid., 1907. 3 Tbid., 191. 
4 Ibid., 1913, pp. 467-487; 1bid., 1914, chapters XV-XVIII; tbid., 1915, pp. 239-243; ibid., 1917, pp. 150-164. 
