CHEMOECOLOGY

, Volume 8, Issue 2, pp 51–60

Chemical defense and evolution in the Sacoglossa (Mollusca: Gastropoda: Opisthobranchia)

  • Guido Cimino
  • Michael T. Ghiselin

DOI: 10.1007/PL00001804

Cite this article as:
Cimino, G. & Ghiselin, M. Chemoecology (1998) 8: 51. doi:10.1007/PL00001804

Summary.

Recent advances in both the systematics and the natural products chemistry of the order Sacoglossa (=Ascoglossa) in the gastropod subclass Opisthobranchia suggest a revised and improved historical account of the evolution of the group. Although the algal genus Caulerpa makes a suitable model for the ancestral food of the order, other siphonaceous algae are consistent with both morphological and chemical data. At an early evolutionary stage terpenoids are sequestered from the food, and used defensively, often with modification. With an evolutionary switch to different kinds of algal food, there is often a shift to other, related defensive chemicals. A switch to new food source sometimes leads to the abandonment of chemical defense, but in other cases there is de-novo synthesis of defensive metabolites. The synthesis of polypropionates, which are used defensively, occurs in some other gastropods, but otherwise is known only in fungi. The systematic distribution of the defensive polypropionates suggests that their defensive use has evolved several times among gastropods. Failure to detect them may mean that synthetic capacity has evolved more than once, or it may mean that they exist at low levels, perhaps having a non-defensive function.

Key words. propionates - adaptive radiation - chemical defense - Gastropoda - Opisthobranchia - Sacoglossa - Ascoglossa - Chlorophyta

Copyright information

© Birkhäuser Verlag Basel, 1998

Authors and Affiliations

  • Guido Cimino
    • 1
  • Michael T. Ghiselin
    • 2
  1. 1.Istituto per la Chimica di Molecole di Interesse Biologico, CNR, Via Toiano 6, I-80072 Arco Felice, Napoli, Italy. E-mail: cim@cim.icmibna.cnr.itIT
  2. 2.Department of Invertebrate Zoology, California Academy of Sciences, Golden Gate Park, San Francisco, CA 94118, USA. Fax: +415-750-7090, e-mail: mghiselin@casmail.calacademy.orgUS