Answer:
33,000 years ago.
Step-by-step explanation:
The "Clovis first theory" refers to the 1950s hypothesis that the Clovis culture represents the earliest human presence in the Americas, beginning about 13,000 years ago; evidence of pre-Clovis cultures has accumulated since 2000, pushing back the possible date of the first peopling of the Americas to 33,000 years ago.