Multicellular Animals

Those who wish for permanence in classifi­ cation must pay the price of stasis - as if for­ ever condemned to confound whales with fish. M. T. Ghiselin 1981, p. 283 Scientific argument is a debate concerned with the solution of unresolved problems. Before continuing with the phylogenetic system of the Metazoa this foreword gives me the opportunity to discuss some controversial ques­ tions, to stat...