It's not an ad hominem. "You're not an anthropologist, so what you said is wrong" would have been an ad hominem. The GP actually attacks the argument, although somewhat incompletely (to be polite).
EDIT: The authority is actually named, it's "anthropology".
1. No. There was no personal attack, and no fallacious reasoning from any personal attack. 2) An intellectual field is a very abstract form of authority, in this context.
1. Saying someone said something is a personal attack? Let me rephrase: "The textual information that became visible to me once the reply button was pressed on your computer" — or is my use of 'your' still out-of-bounds?
2. I didn't include enough detail in my post to actually conclude whether my appeal to authority is fallacious, since that entirely depends on in what manner I'm citing the authority. On the other hand, the post I responded to contained implicit appeals to supposed authoritative information ("There is a universal correlation...", emphasis mine) and the subsequent conclusions based on that authority.
EDIT: The authority is actually named, it's "anthropology".