2002-2003 Science Planning Summary

Biology & Medicine

Dr. Polly Penhale
Program Manager

BO-022-L/P

NSF/OPP 01-25181
Station: RV Laurence M. Gould and Palmer Station
RPSC POC: Rob Edwards
Research Site(s): RV LMG, Palmer Station

The chemical ecology of shallow-water marine macroalgae and invertebrates on the Antarctic peninsula
Dr. Charles D. Amsler
University of Alabama Birmingham
Department of Biology
amsler@uab.edu
http://www.uab.edu/uabbio/s022.htm
Dr. Bill Baker
University of South Florida
Dr. James McClintock
University of Alabama, Birmingham

Deploying Team Members: Margaret O Amsler . Charles D Amsler, Jr. . Billy J Baker . V. Anne Fairhead . Lynn Hollyfield-Jerri . Yusheng Huang . Kevin J Peters . Stephanie T Weiss
Research Objectives: Many organisms are not mobile and so cannot escape from predators. One way they can keep from being eaten is to make themselves unappetizing by producing defensive chemicals known as secondary metabolites. However, the energy and other resources that go into making these compounds could instead have gone into growth or reproduction. This group studies the evolution of these tradeoffs in an effort to understand ways that organisms maximize the usefulness of their investments in defensive chemistry.

For marine plants, the environment of Antarctica is very different from most other places in the world's oceans because nutrients are plentiful but light is often limited. So the "currency" that "pays" for defense, growth, and reproduction is different than for plants in most other marine communities. This allows researchers to test theories about the costs and benefits of defense in ways not possible elsewhere in the world.

For marine animals, Antarctica is unique in that predation by sea stars is much more important than in other marine communities. Sea stars feed by extending their stomachs and digesting prey outside their bodies. These researchers predict that this should lead to a much higher investment in defensive metabolites in the outer layers of the prey. One of the main goals for the 20022003 season will be to test the hypothesis that sponges (a very important component of these communities) will maximize their investment in chemical defense by having the highest levels of defensive secondary metabolites in their outermost layers.

This research should also advance our general understanding of the evolution of chemical defenses. This group hopes to elucidate the nature and role of bioactive agents in the ecology of the antarctic marine benthos (that is, organisms living at the bottom of marine environments).


Field Season Overview:
Project team members will travel to Palmer Station on board the R/V Laurence M. Gould. Divers and their tenders will travel in Zodiac inflatable boats to local sites, collecting marine invertebrates and macroalgae. The samples will be taken to the Palmer Station laboratory for analysis and bioassays will be conducted in the aquarium. Some samples will be returned to the home institutions for further analysis.