Humans are often faced with the choice of investing in the greater good or being selfish and letting others do the work. Animals that live in groups often encounter threats, and informing others could potentially save lives. Researcher of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, show that wild sooty mangabeys, when facing dangerous vipers, do not just call out of fear or to warn their family, but will call when the information about the threat might otherwise not reach all group members.