Final answer:
Large game became extinct during the Paleo-Indian prehistoric period, which ended around 8,000 BCE.
Step-by-step explanation:
Large game became extinct during the Paleo-Indian prehistoric period. During this era, which dates from the time humans entered the Americas until about 8,000 BCE, megafauna such as the mammoth, mastodon, and other large-bodied animals were the primary prey of Paleo-Indians. However, global climate change and human activities contributed to the extinction of these animals. By the time of the Archaic period that followed, humans adapted their subsistence strategies in response to these environmental changes, relying more on plant materials and hunting smaller game such as bison as the previously dominant megafauna had died out.