Answer:
While it is difficult to determine exactly how many Natives lived in North America before Columbus, estimates range from a low of 2.1 million to 7 million people to a high of 18 million.
Explanation:
They live in groups for protection from predators could be one
Conversion disorder.
This is a psychiatric condition on which a person has physical symptoms resulting in paralysis, nervous system that cannot be explained by medical conditions. This can occur because of psychological conflict. People at risk are those with medical illness, dissociative disorder, personality disorder. Symptoms of these disease includes blindness, inability to speak, numbness, paralysis. There are various test that can be done to rule out organic cause of the disease.
