The paper by Gergely Palla, Albert-László Barabási, and Tamás Vicsek explores the evolution of social groups through the lens of clique percolation. They develop an algorithm to investigate the time-dependent dynamics of overlapping communities in large networks, focusing on collaboration between scientists and mobile phone calls. The study reveals that large groups persist longer if they can dynamically alter their membership, suggesting adaptability as a key factor. In contrast, small groups are more stable when their composition remains unchanged. The authors also show that the time commitment of members to a community can predict its lifetime. Using data from the Los Alamos cond-mat archive and a mobile phone company's call records, they demonstrate that the collaboration network is more dynamic than the phone-call network, with larger communities showing higher rates of membership change. The findings highlight fundamental differences in the dynamics of small groups and large institutions, emphasizing the importance of community structure and membership dynamics in understanding social evolution.The paper by Gergely Palla, Albert-László Barabási, and Tamás Vicsek explores the evolution of social groups through the lens of clique percolation. They develop an algorithm to investigate the time-dependent dynamics of overlapping communities in large networks, focusing on collaboration between scientists and mobile phone calls. The study reveals that large groups persist longer if they can dynamically alter their membership, suggesting adaptability as a key factor. In contrast, small groups are more stable when their composition remains unchanged. The authors also show that the time commitment of members to a community can predict its lifetime. Using data from the Los Alamos cond-mat archive and a mobile phone company's call records, they demonstrate that the collaboration network is more dynamic than the phone-call network, with larger communities showing higher rates of membership change. The findings highlight fundamental differences in the dynamics of small groups and large institutions, emphasizing the importance of community structure and membership dynamics in understanding social evolution.