ABSTRACT
Models of the evolution of the life history of most metazoans presume that from each fertilized egg a single juvenile may be produced. Theoretical evaluations of the survivorship of free-living larvae of invertebrates as related to the trade-offs between female fecundity and developmental time also assume that 1 egg results in 1 juvenile (McEdward 1997, Levitan 2000). However, several species of echinoderms, distributed among the Asteroidea, Ophiuroidea, Echinoidea, and Holothuroidea, have larvae that are capable of asexual reproduction (Bosch et al. 1989, Jaeckle 1994, Balser 1998, Eaves & Palmer 2003). These species of echinoderms have fully differentiated planktotrophic larvae that produce and release one or more embryos or larvae. This de novo cloning of “new” larvae is exhibited by uninjured cultured and field-collected larvae and is not a form of regeneration (see Vickery & McClintock 1998). Larval cloning as a component of a life history can increase female fecundity via the production of 1 juvenile per egg thus potentially altering recruitment intensity (Hadfield & Strathmann 1996, McEdward 1997).
