Final answer:
The evidence that Native Americans built the ancient mounds is supported by archaeological and genetic analyses, demonstrating the sophistication and capability of societies like the Fort Ancient Culture and the Natchez tribe.
Step-by-step explanation:
The notion that Native Americans could not have built the ancient mounds found in the Mississippi Valley was based on the European perception of indigenous peoples as mere hunters and gatherers, not capable of constructing such large monuments. This view was challenged by the presence of mound-building societies, like the Fort Ancient Culture and the Natchez tribe, well documented to have lived in North America into the 18th century. Evidence suggests that these societies were structured, organized, and perfectly capable of such feats. The Fort Ancient Culture, for instance, is linked to the construction of the Great Serpent Mound around 1070 CE. The mound's design and lack of typical burial artifacts hint at sophisticated social and religious practices.
Further archaeological evidence has demonstrated the continuity of mound-building cultures and their capabilities, discounting earlier European theories attributing the mounds to Viking, Chinese, or Egyptian builders. Moreover, recent genetic analyses have supported Native American claims, leading to the reburial of ancient remains according to tribal customs, confirming their direct relationship to contemporary indigenous peoples.