Hunter-gatherer groups tend to be small and disparate. They don’t really have much impact on each other.
But they deal with animals, on a daily.
It’s not just primitive societies, either. Modern tribal groups tend to concentrate on animals and crops.
When your very survival depends on knowing as much as possible about prey and draft animals, weather, etc., these topics occupy your attention.
When they depicted other humans, it was often about conflict.
We may think of these as “quaint” beliefs, but these folks took this stuff seriously. Their survival depended on it.
Yeah, we should remember also that permanent or periodic nomadism was the norm on large swaths of the planet. Animals were obviously key to move significant numbers of people (women, children...), as well as to produce food on the go. If the camel-god says no, you're stuck in the middle of the desert, so you better keep him happy.
If you haven’t read Sir Terry, you don’t know what you’re missing.
Moreover, beware of possible biases which could explain what we see today: there is a difference between what we observe and what was. Remember for instance the destruction of the Buddhas of Bamiyan [4], which happened less than 1,500 years after they were built. It is extremely unlikely that a work of art survives for 40,000 years, and some may be more likely to be destroyed than others, depending on location, weather, traditions, history, etc.
[1] https://en.wikipedia.org/wiki/Venus_of_Galgenberg
[2] https://en.wikipedia.org/wiki/Venus_of_Hohle_Fels
[3] https://en.wikipedia.org/wiki/Adorant_from_the_Gei%C3%9Fenkl...