system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Since the Native Americans were here before us, how... did they end up here?

Also didn’t the Vikings discover America or am I ignorant?
gpt
The native peoples of North America predate the Vikings and subsequent European settlers but also came via land migration. All human “tribes” originated in and around Africa and dispersed in all directions, globally. The native North Americans traveled across the Bering straight land mass that was temporarily exposed during a little ice age, allowing human to travel from what’s now north east Russia to Alaska, and migrated downward to favorable weather.