Achilles: Familiar to me? What do you mean? I have never looked at an ant colony on anything but the ant level.
Anteater: Maybe not, but ant colonies are no different from brains in many respects . . .
-- Douglas Hofstadter, Gödel,Escher,Bach
Social insects display some of the best examples of what we call emergent behavior. It is difficult not to become fascinated by the abundance of patterns shown by the work of ants, termites, bees, and social wasps. The huge nests of termites and raid patterns of army ants traveling through the rain forest are just two examples. We are fascinated by their collective behavior, but also by their ecological success: the dry weight of ants and termites in some rainforests is about four times that of all the other land animals (Figure 6.1). In some ecosystems ants compete successfully with rodents and other vertebrates. We find them all around the world, from deserts to the jungle, and they are strong competitors. Some authors even propose that this strong competitive ability leads to a well-defined partition of habitats, with ants and termites playing a central role and solitary insects having much less ecological relevance. 1
But while colonies of social insects behave in complex ways, the capacities of individuals are relatively limited. The brain size of a single ant varies from species to species. In numbers of neurons it ranges over several orders of magnitude. Generally speaking, single ants behave in a simple way. As Holldobler and Wilson have written, "In the course