The International Research Fellowship Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.
This award will support a twenty-four month research fellowship by Dr. Jennifer S. Sorensen to work with Dr. William J. Foley at the Australian National University and Dr. Stuart McLean at the University of Tasmania.
The paucity of mammalian herbivores (<10 species) that consume a single plant species has been attributed to the high concentrations of plant toxins present in such a diet. Little empirical work has been conducted examining the mechanisms mammalian herbivores employ to cope with plant toxins. This project will involve the examination of the role toxin absorption plays in intake of toxic plants by mammalian herbivores. The hypothesis that dietary specialists will absorb fewer toxins per unit ingested than generalists will be tested by measuring toxin intake, blood concentration of toxins, and fecal excretion of toxins by specialists (koalas) and generalists (brushtail and mountain brushtail possums) fed the toxic plant, Eucalyptus. It is predicted that lower absorption of toxins by specialists will result in greater toxin intake yet lower concentrations of toxin in the blood. The PI has found evidence within the genus Neotoma that specialists absorb fewer plant toxins than generalists and proposed research will further expand these results by comparing toxin absorption and the mechanisms that mediate toxin absorption between specialist and generalist mammalian herbivores from different families.