Werner A. Mueller (Müller) was head of the Zoological Institute of the University of Heidelberg, Germany, for 30 years. He is also author of a textbook on Animal and Human Physiology. He and his group did research on stem cells, pattern formation, signalling molecules including neuropeptides and on settlement and metamorphosis of marine organisms. Monika Hassel is leader of the department on Morphology and Evolution of Invertebrates at the University of Marburg, Germany. She and her group use invertebrate model systems (Hydra, Platynereis) to elucidate the role of fibroblast growth factor receptors in the emergence of body plans and the development of boundaries. Maura Grealy is lecturer at the department of Pharmacology and Therapeutics at the National University in Galway, Ireland. She and her group use the zebrafish as model organism to study the onset of transcription in embryogenesis, heart development and the role of signalling cell adhesion molecules.