Different animals have evolved to communicate their impulses to each other in different ways. Peacocks attract females by dancing and displaying their feathers. Certain insects ooze chemicals from their bodies so that others of their species might detect their presence. Non-human apes make sounds and gestures to attract attention as well as to communicate fear, general information, and warnings. Sometimes, apes even lie!
Human beings underwent a cognitive revolution and developed language. In the beginning, they too used language to communicate the same things that other apes did, but eventually, it became that language could be used to do much more. Humans found that not only could they use language to tell their tribesmen that they had discovered a tree, they could also explain where the tree was exactly, what fruit grew on it, and whether there were wild animals around it they should be careful to avoid.
On occasion, when there was the need to communicate why one group of humans was different from another, language began to be used to create imaginary brackets such as clans (we are the tiger people), religions (we are god’s chosen ones), and nations (we stand by this flag). To reinforce these brackets, stories began to be told.
For example, religions are held together by stories like myths, accounts of miracles and prophecies. Holy books are full of them. They become rallying points around which people of a certain faith gather and cooperate.
Similarly, nations are held together with stories which are sanitised versions of historical accounts. These include heroes, leaders, and value systems (which may or may not be drawn from religions).
At the end of the day, the human ape has evolved to tell stories. Stories form the framework that holds human societies together. Stories are the currency that we deal in on a daily basis. And it is not as if the ones I mentioned are the only such stories. Many new stories are being told right now. Some of them will grow to envelope us in the future and might even decide the course of human evolution in times to come.