amer ican ▁p ant he on ▁seem ▁to ▁have ▁begun ▁with ▁the ▁Ol m ec . ▁ ▁Some ▁elements ▁of ▁agricult ure ▁seem ▁to ▁have ▁been ▁pract iced ▁in ▁Mes o amer ica ▁quite ▁early . ▁The ▁domestic ation ▁of ▁ma ize ▁is ▁thought ▁to ▁have ▁begun ▁around ▁ 7 , 5 0 0 ▁to ▁ 1 2 , 0 0 0 ▁years ▁ago . ▁The ▁earliest ▁record ▁of ▁low land ▁ma ize ▁cultiv ation ▁dates ▁to ▁around ▁ 5 1 0 0 ▁BC . ▁Agricult ure ▁continued ▁to ▁be ▁mixed ▁with ▁a ▁hunting - g ather ing - f ishing ▁l ifest yle ▁until ▁quite ▁late ▁compared ▁to ▁other ▁regions , ▁but ▁by ▁ 2 7 0 0 ▁BC , ▁Mes o amer icans ▁were ▁re lying ▁on ▁ma ize , ▁and ▁living ▁mostly ▁in ▁villages . ▁Temple ▁m ounds ▁and ▁classes ▁started ▁to ▁appear . ▁By ▁ 1 3 0 0 / ▁ 1 2 0 0 ▁BC , ▁small ▁cent res ▁co ales ced ▁into ▁the ▁Ol m ec ▁civil ization , ▁which ▁seems ▁to ▁have ▁been ▁a ▁set ▁of ▁city - states , ▁un ited ▁in ▁religious ▁and ▁commercial ▁concerns . ▁The ▁Ol m ec ▁cities ▁had ▁cer emon ial ▁complex es ▁with ▁earth / cl ay ▁py ram ids , ▁pal aces , ▁stone ▁monuments , ▁aqu ed uct s ▁and ▁w alled ▁pla zas . ▁The ▁first ▁of ▁these ▁cent ers ▁was ▁at ▁San ▁Lorenzo ▁( until ▁ 9 0 0 ▁b c ). ▁La ▁V enta