Ancient cave paintings have inspired many things in Graphic Design, and I think this is because we are innately drawn to the contours, simplicity, and shading that you find in many of the cave paintings. I think it is interesting that any design that has ever been created now has already been done in the past, to some extent. It gives graphic designers the ability to not only build off of things in the past, but to bring something new and interesting into our designs in the future.
A cave painting of unknown origin. You can see the simplicity of of the design, the bare minimum of the contours still gives the impression of a horse.
Another cave painting, this one has more coloration and shading.
This is an image of a shawl made by Giorgio di Sant Angelo that works off of cave painting like simplicity and design. It has a native American feel to it as well, which shows that the design has become its own since the old cave paintings.
This logo was designed for a London based literary agency. You can see the use of contour and simple design, both reminiscent of cave paintings.