Meeting Abstract
Our understanding of the genetics of arthropod body plan development originally stems from work on Drosophila melanogaster from the late 1970s and onwards. In Drosophila there is a relatively detailed model for the network of gene interactions that proceeds in a sequential-hierarchical fashion to define the main features of the body plan. Over the years, we have a growing understanding of the networks involved in defining the body plan in an increasing number of arthropod species. It is now becoming possible to tease out the conserved aspects of these networks and to try to reconstruct their evolution. I will focus on two key nodes of these networks. The first is the blastoderm phase in which the main axes are determined and the broad morphological domains of the embryo are defined. The second is the growth zone network, through which posterior segments are added sequentially. The blastoderm network pre-dates the radiation of holometabolous insects and contains a core of conserved interactions. The growth zone network is much more ancient and is probably plesiomorphic to all arthropods. It has undergone a significant amount of systems drift, wherein many of the genes have changed. However it maintains a conserved underlying logic and function.
