Life on Earth is in constant motion. Humans and other species move from their place of birth to new physical and social environments, often at great risk. What is the significance of this movement?

In addition to a talent for migration, humans have evolved an amazing ability to be in contact with many generations. In society after society there is apparent effort to maintain knowledge about ancestors and a connection to their lives through oral history, pictographs, letters, journals, and volumes of recorded history. Every human life is connected to generations who went before. In families there are many ways of maintaining connections to the stream of life that is one’s personal or collective past. What happens to humans when that current of contact and knowledge is cut off?