surely coincidental :) Well, yes, probably. More interesting than false alien visitation theories is the extent to which these images may represent cultural borrowing or even travel over thousands of miles in a non technological age.
While Easter Island is famous for its large heads, these are perhaps more mysterious than those. Explorers found these tablets, but cannot decipher them. It might be the last remnants of the Rongorongo language in history, but no one knows for sure. If you think this is crazy, check out number 5 for another unexplained set of tablets.
Ancient pyramids all over the world. How strange that the same design pops up over & over, so far away from the others.<it might just be the best way to build something up and walk on it, in those time periods.