Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic inflammation of the joints. Autoimmune diseases are illnesses that occur when the body's tissues are mistakenly attacked by their own immune system.
What role did the bison or buffalo play in the culture of the Plains Indians? The bison were an important source of fur, food, and shelter for the Plains Indians. They used every part of the animals they killed. Bison were also an important part of their culture.
While the popular image of Plains Indians is that of the horse-mounted warrior and buffalo hunter, the horse as we know it today only came to this continent with the Europeans. It reached the Plains Indians and dramatically changed their ways of life several generations before the Americans invaded the area.