Colonies as byproducts of commodity selection

When ecologists examine a colony, they tend to ask, what are the benefits of breeding in aggregations? In contrast, when students of leks examine an arena of displaying males, they usually ask, what are the mechanisms that produce aggregations? Here we discuss the differences in these two approaches. The value of this distinction stems from the frustrating inability of decades of research to provide a general explanation of the widespread occurrence of colonial breeding. The traditional approach to studying coloniality is the measurement of costs and benefits of breeding in high density. Our aim is to illustrate how individuals can pursue adaptive strategies that result in their joining breeding aggregations without necessarily obtaining net benefits from the aggregation.