The selective advantage of colony growth in the western harvester ant, Pogonomyrmex occidentalis

There is little information about the operation of selection on natural populations of social insects. Without this information it is difficult to know how to interpret studies on a wide variety of other processes that are important to social insects, such as the evolution of caste systems or sexual investment ratios. In this paper we will present information on the relation of colony growth to survival and reproductive output in the western harvester ant. We will draw upon our long-term data set that contains information about growth and survival in some 3000 colonies. We will present information on year-to-year variation on the selective consequences of colony from 19 years of study on this population.