Changes in a short protein domain can alter a whole signaling network involved in organ development – this is the key result of a comparative study of the development of the egg laying organ in two species of nematodes. However, the outward appearance of the organ remains the same in both species. The study provides support for the theory of developmental systems drift – a theory maintaining that, over the course of evolution, analogous organs of different species can retain the same shape and function while the regulative mechanisms underlying their development can change considerably.
for Evolutionary Biology The nematode Caenorhabditis elegans (C. elegans) is a model