Yeh, but back then "genius" was a bow and arrow instead of a hand thrown, or stabbing, spear.
Did mankind know about seasons, phases of the moon, etc?
Sure they did, it was all around them. They marked the spring summer, fall, and winter equinoxes. It is pretty much a given that when the sun stops drifting in one direction and starts going in reverse that someone is going to notice.
Eventually someone will make the discovery that so many days after one of these events the plants start budding and growing, or so many days after another of these events it gets colder.
That's not genius, that's attention to detail.
Mostly genius is good pattern detection.
......that’s attention to detail.....
It is science..... the study of the heavens