1989: the most popular animated ensemble comedy of all time appeared on the FOX network. Nobody at the time expected that The Simpsons would span two decades, but the saffron superstars achieved the feat. Could it be that one of the reasons why is because the Simpson family is augmented by a city full of recurring, familiar characters? Krusty the Clown. Apu. Sideshow Bob. Ned Flanders. Moe the Bartender. The Comic Book Guy. Mr. Burns and Smithers. Nelson. Chief Wiggums and dozens more. Some of these characters have been strong enough to carry entire episodes, and more than a couple could probably prosper in spinoffs. To know the Simpsons is to know Springfield, and to know Springfield is to belong. And belonging, dear reader, explains quite a bit.

How many characters are on SpongeBob?

Belongingness theory is a relatively new concept: the landmark paper The Need to Belong by R.F. Baumeister and M.R. Leary dates to 1995. The initial groundwork, however, was laid in 1956 by researchers Donald Horton and Richard Wohl, who posited that television viewers form "parasocial relationships" with personalities and actors observed on television. Simply put, we become part of their family and relate to them as if we are on familiar terms with them. We know their mannerisms, catchphrases and in-jokes of their circle, and thus we belong to it by extension.

What Baumeister and Leary did was transpose the concept of parasocial relationships to evolutionary psychology; the need to belong has vital, biological roots that ensure survival of both individual and species due to the simple fact that people survived better in groups than alone. The final step in the evolutionary process is an actual physical desire for social interaction and inclusion.

Some psychologists, such as Dr. Jaak Panksepp, take it even further, claiming that close social relationships actually produce opiate-like neurochemical reactions in the brain itself. In some cases parasocial relationships are so powerful that soap opera actors have received hate mail and threats from viewers for breaking up marriages that in fact exist only in scripts. The larger and more diversified the "family" (read ensemble cast) the more opportunities to join and belong. This may well be what Cheers and The Simpsons have most in common.

I won't rest my argument on one animated series. Has anyone noticed how large the cast of SpongeBob SquarePants is? Besides the great quartet of SpongeBob, Partick, Squidward and Mr. Krabs, there's Sandy Cheeks, Mrs. Puffer, Pearl, Larry the Weightlifting Lobster, and many other oft-seen denizens of Bikini Bottom. The show is also one of the most popular ever to be developed for a cable network and has as many adult fans as child fans. How about South Park? I defy anyone to look at the large, recurring cast and not define this show as an ensemble comedy. Has it been long-running and popular? You bet your cheesy poofs. King of the Hill? Same idea. Futurama was so popular that is was brought back from the dead to entertain a new wave of fans. And let's not forget one of the very best efforts to come out of Adult Swim: The Venture Bros., with its multitudinous cast of screwed-up heroes and villains was more than just a cult hit.