I would ignore them, maybe you being new and shaking up their clique has probably earned you a few glares. I would doubt its because of your looks (dont get me wrong you are probably v attractive) but there are lots of attractive women who get on fine with everyone, I know several who have the men virtually drooling on the floor when they walk in a room!! lol
but they are very nice people and everyone likes them men and women alike, maybe they are trying to work you out, if you are shy and quiet that can be taken as aloofness or moodiness in some people.