The origin of dorsoventral patterning of the vertebrate nervous system

Abstract

The fields of evolution and development have a close affinity in that they both concem themselves with the problem of the generation of form. Studies in either discipline complement each other, and have led to a dearer perspective of how the structure and order of the body plan arise. More recently, now that we have a molecular understanding of developmental processes, cross-fertilization between these two fields los greatly increased. This has allowed evolutionary relationships to be probed to a greater extent than before and h~s also revealed a surprising depth of conservation. Moreover, we are now beginning to get information regarding the evolution of developmental pathways themselves. One area in which this is particularly tt-de is in our understanding of the patteming of the nerve cord.