PLATE 19 
cM. | 2 3 4 5 6 7 8 9 10 
Plate 19. Evolution in ear length in 6500 years in the Tehuacan Valley, Mexico. The 
approximate ages of the cobs from left to right are 7000, 5300, 2200, 450 and 450 years 
respectively (23). This evolution, rapid as compared to that of other cultivated plants, 
is partly the product of wild corn’s preadaptation to domestication by virtue of its large 
pollen as revealed by the fossil remains from the Bellas Artes site, Mexico. 
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