Evol Ecol Res 11: 1069-1083 (2009)     Full PDF if your library subscribes.

Long-term storage lipids and developmental evolution in echinoderms

Thomas A.A. Prowse1, Inke Falkner1, Mary A. Sewell2 and Maria Byrne1

1Anatomy and Histology, Bosch Institute, Sydney, Australia and  2School of Biological Sciences, University of Auckland, Auckland, New Zealand

Correspondence: T.A.A. Prowse, Anatomy and Histology, Bosch Institute, F13, University of Sydney, Sydney, NSW 2006, Australia.
e-mail: tprowse@anatomy.usyd.edu.au

ABSTRACT

Question: How is maternal investment of energy storage lipids linked to the evolution of development for echinoderms with larval phases?

Hypotheses: Egg nutrients sustain development to the exotrophic larval stage in echinoderms with feeding (planktotrophic) larvae and to the exotrophic juvenile stage in species with non-feeding (lecithotrophic) larvae. Whereas planktotrophic echinoderm development requires egg lipid reserves that are readily metabolized, lipids suitable for long-term energy storage might be more appropriate fuels for lecithotrophic development.

Organisms: We considered closely related asteroid and ophiuroid species that possess a range of egg sizes and represent three modes of larval development (planktotrophy, planktonic lecithotrophy, benthic lecithotrophy).

Methods: We used Iatroscan TLC-FID to quantify maternal investment of lipids on a per egg basis for each species and focused on egg content of the two dominant classes of energy storage lipid, triacylglycerol (TAG) and diacylglycerol ether (DAGE).

Results: Energetic lipids in the small eggs of echinoderms with feeding larvae are primarily TAG, a class of short-term storage lipids. DAGE, which is metabolized more slowly than TAG, dominates the large eggs of echinoderms with non-feeding larvae. Increased deposition of DAGE lipids in the eggs of planktotrophic species may facilitate the transition to lecithotrophy.

Keywords: developmental mode, diacylglycerol ether, echinoderm, evolution, Iatroscan, lipid, triacylglycerol.

DOWNLOAD A FREE, FULL PDF COPY
IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.

 

        © 2009 Thomas A.A. Prowse. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.