Much has been written about how social media confirms our biases. While platforms like Twitter, Facebook, and Instagram are ubiquitous, we limit our networks to individuals and companies that are of interest to us, both professionally and personally.  A liberal-leaning individual may follow MSNBC commentator Rachel Maddow, but isn’t likely to follow Bill O’Reilly for information (but may for snark-related purposes).

So far, the selection of “networks” has been done by a user following profiles of interest on a large platform. One interesting trend we’ve seen is the emergence of silo-based social platforms in which the network is limited to a certain population of users.

For example, instead of a LinkedIn group for public safety officials, there is a dedicated and encrypted network dubbed BlueLine. Mashable reports public safety officials must be screened, and can use the network to collaborate on best practices without wider scrutiny.

It’s not limited to the public safety community. There is Figure 1, an Instagram-style photo sharing site on which doctors can share (anonymous) pictures of scans and patients to solicit feedback and ideas for treatment. RallyPoint, a network for members of the military, features an extensive chart of all U.S. military locations around the world, and allows users to network with those stationed at the bases. For retired military members, there is Together We Served.

These networks may evolve. LinkedIn may snap up the technology that makes these networks more useful to professionals in given fields in order to maintain its dominance as the professional networking tool of choice. After all, Facebook started out as a network for college students before evolving into a platform even your grandparents use. Savvy businesses will keep an eye on developing niche social media opportunities—you never know which startups will be the next to take off.