Protostomy? Deuterostomy? Does it really matter? – About a major split in the Animal Tree of Life
Friday seminar by Andreas Hejnol, Sars International Centre for Marine Molecular Biology
Over 100 years von Groppen subdivided all bilateralsymmetric animals into Protostomia and Deuterostomia using embryological characters. Recent molecular phylogenies support this grouping, but a closer examination of the embryology is drawing a different picture. All deuterostomes form the mouth separate from the blastopore, but protostomes show a high variability in the fate of the blastopore. I will provide new developmental data from different protostome taxa that suggest that deuterostomy is ancestral for the protostomes and thus for all Bilateria. I will outline the impact of these finding for our understanding of animal body plan evolution.