Complexity, pattern, and evolutionary trade-offs in animal aggregation

One of the most striking patterns in biology is the formation of animal agg regations. Classically; aggregation has been viewed as an evolutionarily ad vantageous state, in which members derive the benefits of protection, mate choice, and centralized information, balanced by the costs of Limiting reso urces. Consisting of individual members, aggregations nevertheless function as an integrated whole, displaying a complex set of behaviors not possible at the Level of the individual organism. Complexity theory indicates that Large populations of units can self-organize into aggregations that generat e pattern, store information, and engage in collective decision-making. Thi s begs the question, are all emergent properties of animal aggregations fun ctional or are some simply pattern? Solutions to this dilemma will necessit ate a closer marriage of theoretical and modeling studies Linked to empiric al work addressing the choices, and trajectories, of individuals constraine d by membership in the group.