Final answer:
The native population declined by 90% following Columbus's arrival due to disease and European conquest.
Step-by-step explanation:
Since Columbus's arrival, 90% of the native population was decimated, mainly due to diseases like smallpox, influenza, and measles.
Initially, the Western Hemisphere was home to an Indigenous population of roughly seventy-five million. Colonization brought deadly diseases to which natives had no immunity, leading to significant demographic changes. Entire tribes were wiped out, and in some areas, such as Hispaniola, the population dropped from millions to mere hundreds. The catastrophic decline was exacerbated by forced labor, war, and other factors related to European conquest and colonization.