Miguel Pais points to an interesting behavior of Mathematica, where he plots the function which is the square of the square root of x. Now, if the domain of x is taken to be complex numbers, Mathematica’s behavior seems to me to be fine. But can anyone explain this behavior

as anything other than a bug?

**Update:** Oops. That wasn’t the one I was trying to paste. See what happens when I disconnect from the intertubes for a few days. How about this one: