Humanity for centuries has perfected skills of interpersonal interactions and
evolved patterns that enable people to detect lies and deceiving behavior of
others in face-to-face settings. Unprecedented growth of people's access to
mobile phones and social media raises an important question: How does this new
technology influence people's interactions and support the use of traditional
patterns? In this paper, we answer this question for homophily driven patterns
in social media. In our previous studies, we found that, on a university
campus, changes in student opinions were driven by the desire to hold popular
opinions. Here, we demonstrate that the evolution of online platform-wide
opinion groups is driven by the same desire. We focus on two social media:
Twitter and Parler, on which we tracked the political biases of their users. On
Parler, an initially stable group of right-biased users evolved into a
permanent right-leaning echo chamber dominating weaker, transient groups of
members with opposing political biases. In contrast, on Twitter, the initial
presence of two large opposing bias groups led to the evolution of a bimodal
bias distribution, with a high degree of polarization. We capture the movement
of users from the initial to final bias groups during the tracking period. We
also show that user choices are influenced by side-effects of homophily. The
users entering the platform attempt to find a sufficiently large group whose
members hold political bias within the range sufficiently close to the new
user's bias. If successful, they stabilize their bias and become a permanent
member of the group. Otherwise, they leave the platform. We believe that the
dynamics of users uncovered in this paper create a foundation for technical
solutions supporting social groups on social media and socially aware networks.Comment: 7 pages, 4 figures, submitted to IEEE Communications Magazin