Reciprocal altruism

mechanistic work on the response threshold concept, I think this part of the book reviews important work in social insect biology and in behavioral genetics in general. Page finishes his book by focusing on the reproductive ground plan work he has conducted in recent years with Gro Amdam and others. This is the study of how core genetic modules (primarily relating to reproductive physiology) have been reshaped by selection for eusociality. The idea was originally proposed by West-Eberhard for social insects, and has strong overlap with evo-devo ideas in general. Page also touches on work conducted with Timothy Linksvayer and others on indirect genetic effects on social behavior. This work explores how genes expressed in relatives (parent/offspring/siblings) interact with genes expressed in individuals to shape phenotypes that occur at both the individual and colony levels. Both of these research agendas are ongoing and are at the vanguard of research into social evolution. Page does a good job of reviewing the work done in his lab. In summary, when studying a complex system it is often useful to take careful stock of where we are versus how far we have to go. In studies of vertebrate brains, for example, this is inescapable since our understanding of these systems pales in comparison to their complexity. It is entirely possible to learn massive amounts about the behavior of individual neurons without understanding how the neurons function as a group when linked together into large circuits. In the study of simpler, yet still profoundly complex systems, such as honey bee colonies, similar themes are present. Even though I do not think Page has captured the “spirit of the hive” in his book, I do think he has reviewed careful and important work on honey bee physiology and genetics, and I think that this review will ultimately enrich our understanding of these societies at every level of biological organization.