This is a single-panel cartoon by War and Peas. The image depicts two cavemen sitting across from each other with a pile of rocks between them. They are both seated on rocks, facing one another. One caveman has long hair and a beard, while the other has a slightly more rugged appearance. The caption below the image reads, “Let’s settle this with a game of Rock Rock Rock.”
This was stolen from an old farside comic. Search farside rock paper scissors
Damn… War and peas did a bit of a joke steal