History of Mesoamerica (Paleo-Indian)

In the History of Mesoamerica, the stage known as the Paleo-Indian period (or alternatively, the Lithic stage) is the era in the scheme of Mesoamerican chronology which begins with the very first indications of human habitation within the Mesoamerican region, and continues until the general onset of the development of agriculture and other proto-civilization traits. The conclusion of this stage may be assigned to approximately 9000 BP (there are differences in opinion between sources which recognize the classification), and the transition to the succeeding Archaic period is not a well-defined one.

Its starting-point is a matter for some contention, as is the more general question of when human habitation in the Americas was first achieved. While it is accepted by a significant number of researchers that the peopling of the Americas had occurred by c. 11,200 years ago, a number of claims have been made for evidence of human occupation which precede this, some as far back as c. 40,000 years. General and majority scientific consensus for these (much) earlier dates remains elusive, however, and evidence for these claims is yet to be fully accepted.

Scientific opinion regarding human antiquity in Mesoamerica has reflected larger trends in conceptualizing human antiquity in the western hemisphere in general. Within that foundational topic, the establishment of sites demonstrating human antiquity in Mesoamerica has centered on the association of remains and artifacts with geologic strata (context) and on the reliability of the dating of the remains and strata (methodologies).

At the beginning of the twentieth century, humans were believed to be very recent post-glacial immigrants to the western hemisphere. Although there was believed to have been anywhere from 20,000 to 60,000 years of post-glacial time in which such immigration could have occurred over the Bering land bridge, the antiquity of human presence in the western hemisphere was popularly fixed at about 5,000 BP ("before present", or 3000 BC).

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