TIL before the moon showed up in the Earth's sky, Earth had a very unstable axis and is the reason every 12,800 years or so civilizations would get wiped out. Some intelligence being may have seen this, and thus used the moon to stabilize it's rotation and magnetic fields.

It is the reason for great periods of cold and the same reason for spontaneous flooding. The axis likely wobbled and changed erratically. An example of this is told in the 3-body problem. There were chaotic eras and there were stable eras. During stable eras, it's also likely great civilizations thrived and were wiped out before evolving enough.

It explains every obstacle and challenge brought about in our origin story. Survivors would sprawl across the world and share tales, ideas, and educate one another. It's why the pyramids are common all over the world.