The sources that seems most useful in understanding human history before writing are:
However out of these, the one seems most useful in understanding human history before writing is Discoveries of human fossils.
Fossils is one of the best way to provide us with the useful insight into the history of life on Earth.
It help the researcher to be able to know how life started life and where humans came from.
It gives the relationship between Earth and our environment and how these has changed with geological time.
Learn more about human history at:
https://brainly.com/question/25670011
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