Decoupling of fission and regenerative capabilities in an asexual oligochaete

摘要: Agametic reproduction by fission has evolved numerous times in the Annelida. In this group, as well others, developmental processes of appear to be based on those regeneration. Thus far, all fissiparous annelids whose regenerative abilities have been investigated fully are capable regenerating both anteriorly and posteriorly. However, paper, I describe a unique exception association between abilities. Regeneration experiments demonstrate that annelid Paranais litoralis (Oligochaeta: Naididae) lost capacity for full anterior The four segments P. produced routinely during each round fission, yet species is incapable producing these same propose reproduction, possibly coupled with low susceptibility amputation nature, may relaxed selection regeneration litoralis. decoupling suggests some steps trajectories lead diverged species.