Since when is beauty a Supreme Court requirement?

I've noticed a lot of people on the right -- usually in the comments sections of blogs and political news sites -- viciously criticizing U.S. Supreme Court nominee Elena Kagan, not on her professional qualifications, but rather on her appearance.

Some examples:

• From "joe r" at a CNN blog:

"what on god's green earth is that ugly blob? Is that a man or a woman?"

• From "gringott" at the Daily Caller site:

"At least she only ties Ginsburg for ugly."

• From "Oldexpat" at the Free Republic:

"So now we will have two fat ugly female supreme court justices. What kind of example will they set for our young women?"

And these few examples are just the tip of the iceberg.

Since when is physical beauty a requirement for a Supreme Court justice?

And why then is Scalia (who is no Brad Pitt) allowed on the bench?

Rhetorical questions, of course. But apparently not for some.

Of course, ad hominem attacks are the last (and sometimes only) refuge of those who are unable to argue the real issues. And the character of anyone who resorts to such attacks is surely far uglier than anyone a president could nominate.