‘ 
names, some of which are regarded as ‘‘primitive,’’ as- 
sociated with maize, its culture and uses, which have 
affinities with those of Central America, Ecuador, Peru, 
Venezuela, and the South American lowlands. Roberts 
et al (36) have suggested that such a situation might have 
developed if this region had been not a center of origin 
but a crossroads in which the cultures of Central Amer- 
ica, the Andean highlands, and the South American 
lowlands converged. That northern Colombia was defi- 
nitely a crossroads region is now generally accepted by 
anthropologists. Evidence from a study of Colombian 
races of maize tends to support this interpretation. Other 
aspects of the case for a Colombian origin have been re- 
viewed by Mesa Bernal (34). 
THe TIME or ORIGIN 
The fossil maize pollen of Mexico, presumably that of a 
wild corn, is assigned, on the basis of systematic changes 
in the frequency of other types of associated pollen, to 
the last interglacial period. Recent estimates place this 
at 80,000 years or more ago. There is no reason to doubt 
that wild maize is much older than this. 
The origin of cultivated maize is, of course, much more 
recent. The oldest archaeological specimens so far stud- 
ied, those of Bat Cave in New Mexico, are dated by 
Libby’s radiocarbon determinations of associated char- 
coal at 5,600 years. There is a possibility that the pre- 
historic maize and charcoal are not contemporaneous; 
that the charcoal is a residue of fires built by itinerate 
campers long before the cave was occupied by maize- 
growing people. ‘This date, however, is not inconsistent 
with those from other sites. The oldest corn from La 
Perra Cave, dated by radiocarbon determination of asso- 
ciated vegetal remains at 4445 years, is by no means as 
primitive as the earliest Bat Cave specimens. The oldest 
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