Anthropology

Unlike later cultures, like the Egyptians, Indians, Chinese, Early Greeks, Africans, etc. whose art became stylized, so much so that we tend to think of "primitive" and "ancient" artists as lacking skill, but that's only because earlier cultures imposed societal norms and symbolism on their art, especially if they developed formal art instruction. Naturalism was sort of "rediscovered" by the Greeks and Romans, and again in the Renaissance, and once again with photography. But there has always been this tendency to distort the natural world in art. I suspect prehistoric artists were less encumbered by such cultural baggage so the beasts are still recognizable to us today.