Final answer:
Stratigraphically, pre-Clovis sites such as Monte Verde in Chile predate the Clovis culture, with evidence of Clovis artifacts found in layers above those of pre-Clovis cultures like at the Debra L. Friedkin site in Texas. This indicates a sequence of occupations with pre-Clovis peoples inhabiting the Americas before the Clovis culture emerged.
Step-by-step explanation:
In terms of stratigraphic relation, Clovis and pre-Clovis cultures represent sequential occupancy with pre-Clovis as the earlier cultural manifestation. Sites like the Debra L. Friedkin site in Texas, with a stratigraphy that includes a sequence from 13,500 to 15,500 BP, provide examples of pre-Clovis tool assemblages underneath those associated with the Clovis culture. Subsequently, stratigraphically above the pre-Clovis levels, we often find Clovis artifacts, which have been typically dated between 13,000 to 12,600 years ago. This layered stacking indicates that pre-Clovis peoples were present in the Americas before the Clovis culture emerged.
The Monte Verde site in Chile further supports the pre-Clovis presence with its array of well-documented cultural remains, dated to 14,800-13,800 BP, which predates the Clovis period. Stratigraphically, the Clovis culture's characteristic tools and artifacts would be found above those of the older pre-Clovis sites, such as Monte Verde, in sedimentary sequences. This evidence indicates that first inhabitants did not necessarily follow the Clovis-first migration theory, as previously thought but suggests earlier human presence in the Americas.