The paper introduces the concepts of individual survival strategies (ISS) and social survival strategies (SSS) and presents three sets of simulations of a particular type of SSS: the Central Store (CS) strategy, according to which the individuals in a group contribute part of their resources to a central mechanism that can redistribute these resources or make other uses of them. CS and ISS both allow a group of individuals to survive in a favourable environment although group size is slower to reach a steady state in the CS group because of the lower selective pressure on individuals' resource production. However, only CS groups survive in a less favourable environment apparently because the CS functions as a safety net for the individuals in the group. Although CS strategies can have this and other advantages over ISS, if individuals are left free to decide whether or not to give their resources to the CS, they tend not to do so. In other words, they abandon the CS strategy and revert to ISS. Because CS strategies characterize an increasing number of human societies since Neolithic times an important research problem is to identify and reproduce in the simulations, how groups of individuals that tend to act egoistically and not to give their resources to the CS, can be induced to do so.
