..how did stories help us our species evolve?
Throughout our evolution, natural selection has found various ways to ensure the production of reproductive adults. For example tree frogs evolved poisonous skin that predators learned to avoid.
The young could now learn from observing the experiences of their parents. Mime stories contained more experiences than any youngster could expect to acquire personally in a lifetime.
Telling whole stories was a single huge jump that potentially allowed youngsters to understand and prepare for experiences that could occur in their own future, the culmination of millions of years of natural selection.