There's a certain primate behavior (usually among male primates) that I see time and again in Internet communities (e.g., chat boards) that I find disturbing: a new monkey drops by and makes a comment, and the "accepted monkeys" of the group immediately start giving him a hard time, at least until they're used to him and he becomes an accepted member of the community.

That said, I see that sort of thing far less in Mudcat than in other Internet communities. This is generally one of the most welcoming communities around.