Conversation so far:
What can you tell me about the early history of Blackfoot Confederacy?
The Niitsitapi, also known as the Blackfoot or Blackfeet Indians, reside in the Great Plains of Montana and the Canadian provinces of Alberta and Saskatchewan.
When did the Niitsitapi reside in the Great Plains?
Where did the Niitsitapi migrate from?
Due to language and cultural patterns, anthropologists believe the Niitsitapi did not originate in the Great Plains of the Midwest, but migrated from the upper Northeastern part of the country.

Question: How did they adapt to being in the plains?
Self-contained rewrite: How did the Niitsitapi adapt to being in the plains?