History
a dot
A decade.
pagkalat
You have answered the question yourself. It was the period of time we call 4000 BC to the period known as 3000BC.
Tens of thousands of years ago the land we call south caroina didn't keep records and we call that prehistory
prehistoric
In historical terms a time before written records is called prehistoric. Prehistory can a vast period of time from the beginning of the universe until writing systems were created. Prehistory generally focuses on the relatively recent appearance of humans and human-like creatures.
If you assume that the Ancient Era ended with the sacking of Rome and the Modern Era began with the Rennaissance, then the period in between was the Medieval or "Dark" Ages. Dark because of the lack of written records from that period due to the low levels of literacy.
Alphabetic.
There was no written information or data taken during that time period.
There was no written information or data taken during that time period.
western civilization
There is no set period of time mandated by law. Obviously large schools must "retire" their older records eventually. If you need to know, call the school you are interested in and ask.
A group of scholars
A form of writing we call today Cunieform was invented about 3,500 BCE to keep written records.
Diaspora.
Skype makes call records available. One can also contact their local phone company to retrieve personal phone records. Cell phone records are available on monthly bills.