Monterey Bay Aquarium Research Institute

Polychaetes, species concepts, and least inclusive taxonomic units (LITUs)

Fredrik Pleijel, Ph.D.
 Muséum National d'Histoire Naturelle

Monday, September 20, 2004
Pacific Forum – 2:00 p.m.

A discussion is provided on current problems relating to species concepts and their application, mainly the “biological species concept” and the “phylogenetic species concepts.” Case studies, mainly on polychaetous annelids, will be used as examples. It is argued that most statements about species are unwarranted, and that species as “a central unit” in biology should be abolished. An alternative, “least inclusive taxonomic unit” (LITU), is presented, which does not identify species as taxonomic entities, but instead refers to the least inclusive clades that currently are recognized.