Explain the concepts 沙雕 and 沙雕图
In addition to meanings explained by other answers, 傻屌 are much more offensive and vulgar than沙雕.

沙雕 is generally used humourously to describe weird or stupid but funny behaviours or lame jokes, as with a lot of memes. It is still vulgar but I would not call it offensive (unless it is directed to a person as an insult and used to avoid censorship of 傻屌). You will see mainstream websites use 沙雕 (e.g. 沙雕网友) liberally (not in serious news, though).