I observed a college aged female. She was not dressed in any particularly defining way (eg. No greek letters, or thick framed glasses). She was reading and talking to her friends, all of which were female. She seemed to be discussing some paper which her entire group was reading. She appeared to be happy in the company of her group. She smiled frequently. She did not interact with anyone outside her group for the entirety of my observations.
My vantage point was fairly good so it was easy to see the entire room. There were mostly groups of college age people interacting amongst themselves. The groups seemed to keep to themselves though, and it did not appear that any of the individuals in any of the groups were interacting with anyone outside of their group. The groups were almost all same-sex. The girls stuck with the girls, and the guys stuck with the guys.