Bear with me.
Early man burned a lot of calories chewing raw meat:
Once we discovered fire and cooking, we didn’t have to work as hard to eat — so evolution put the excess calories to work growing our brains:
Bigger brains meant bigger heads — at the same time that standing upright was shrinking our hips.
Maybe you can see where this is going — bigger heads plus narrower hips meant painful childbirth.
So, evolution started favoring premature births.
Which explains why some animals are walking and hunting within hours of birth and human babies just kind of lie there for months.
So, we needed a relatively fast tool for teaching, socialization, and survival skills.
That’s when our big brains started paying for themselves. Bigger brains gave us the ability to abstract — to imagine. Which lead to storytelling.
And we’ve been teaching through stories ever since!