Four stages of group formation
A community is not the same thing as a team. A community is group of people who interact socially. A team is a group of people who work together on the same task. These are orthogonal: A group of people could be both, or either, and if it's neither then it's probably not a group at all.
Teams are ancient human nature, but are mostly found these days not as groups of related men with pointed sticks seeking an antelope to kill and eat, but as groups of unrelated people sitting down and banging away at rows of little plastic squares in return for a slip of paper with numbers printed on it. Human nature is still the same.
One does socialise with one's work colleagues to some extent unless one makes a determined and mean-spirited effort to avoid it. One talks about TV shows,
sporting events, politics, holidays and family. You fetch coffee, you go for drinks. And so on. The social dynamics of a team determine a lot about how well it works.
According to the management wonks1, team formation and social dynamics go though four stages, called forming, storming, norming, and performing.
The Four stages:
Forming: What you get when you put a bunch of strangers in a room together: polite, superficial, neutral, non-invasive conversation about inoffensive topics such as weather and sport. People get to know each other at a safe distance. Some personal information is cautiously volunteered.
Roles and responsibilities are unclear. The team members don't really know what the team's aims are, other than what they have been told.
A leader must give direction and answer lots of question during this stage.
Storming: People get to know each other, and get close enough to occasionally get too close. People's comfort zones are challenged as a safe distance is established. Cliques and factions may form, and the appointed leader may be challenged.
A pecking order is hammered out and people jostle for status and to find niches for themselves, and define their specialities. If there are powers struggles, this is when they will be.
Decisions do not come easily. The team's aims become clearer to individual team members, but there may be disagreements or differences of approach. A leader may need to set expectations of suitable behaviour.
Norming: If the storming issues are resolved, consensus is reached, and the social structure becomes stable. Trust deepens, norms coalesce, expectations are named and negotiated, bonding occurs, in-jokes are established and people feel comfortable with each other and their roles and responsibilities in the team. Team members learn each other's strengths and weaknesses.
Mostly there is now there is agreement. Where there isn't, facilitation generally works.
Socialisation, having fun together, blossoms at this stage.
Performing: The team works together without friction. The level of efficiency may be less than it could be, depending on what happened in the last two stages, but it is consistent, and higher than it was while storming conflicts were consuming energy. Members know each other's strengths and weaknesses. Loyalty is a benefit of this stage.
Disagreements can generally be resolved within the team. At this stage, teams can work mostly autonomously, with members understanding not only what they should be doing, but also why. Hopefully they can also use the why as a guideline, to vary what they do in response to changing circumstances.
Beyond the four stages
Later on, a fifth stage, Adjourning was added. I don't know much about it, but turiya adds: "Adjourning was added because every team/group eventually ends. A good leader/facilitator will make sure there's some kind of proper closing, as people do mourn the ending of groups, even those focused on inane tasks."
The dogma is that any change to the team, even adding a new guy or removing someone, sends it all back to stage one. Perhaps showing the FNG the ropes is faster than forming the platoon in the first place, but the four stages and issues are still reviewed in the same order, and the group dynamics will not end up the same. This might involve an improvement, or it might not.
Some software development gurus say "don't break up gelled teams", i.e. teams that are performing and are doing it well. However given the inevitability of staff turnover and the fluctuation of workload it is not often that you even have the choice to keep the team exactly the same.
Does this model apply to online communities such as Everything2? Not exactly. Online communities are much more fluid and open, also larger and more diverse. The broad community is perpetually forming and storming at the edges, and generating enormous amounts of "norming" style in-joke material, probably in implicit effort to create bonds. However you may well see more fixed subgroups and circles of interest that have the focus and stability to reach or even get through the norming stage.
How long does it take to get there? That isn't discussed much, so I shall guess that forming might take a week or more before the storms start. Storming will go on as long as it has to. In pathological cases, it goes on indefinitely, until the team membership changes. Norming, merging into performing, can happily tail off over a long period. Months, at a minimum.
1) "Bruce Tuckman's 1965 Forming Storming Norming Performing team development model"