Mafia-like Behavior Birds (IMAGE) Max-Planck-Gesellschaft Caption Theoretical frequency of mafia behavior in a population (simple model with one egg per season). Mafia-like parasites (above) appear cyclically more and less frequently. Similarly, the frequency of host birds (below) which accept a foreign egg immediately or only after their eggs have been destroyed varies (conditional accepters). Credit <i>Scientific Reports</i>, 2014 Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.