The Dogon

Two hundred miles south of Timbuctu lies a vast plateau of sandstone. After rising gently for 150 miles it suddenly drops sheer for over 900 feet, the result of a gigantic disturbance in the earth's crust. At the foot of this vast cliff live the Dogon - one of the most mysterious tribes in the continent of Africa.
One of the complex ideas which the Dogon hold on life is that each human being is mirrored by a twin in the animal kingdom. As a result, a man is forbidden to kill the animal with whom he shares a part of his soul, but if by accident or design he does so, then he kills part of himself.