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Genetics Program |
My research focusses primarily on the ecology and evolution of chemical
defense in birds and the evolution of suites of characters that are often related
with chemical defense, such as bright coloration and morphological variation.
In my Ph.D. work, I have used both field and laboratory techniques to study
the avian genus Pitohui, which includes five toxic New Guinean bird species.
Pitohuis carry a potent neurotoxic alkaloid in their skins and feathers, presumably
for defense. Pitohuis provide an interesting model system for the study of chemical
defense and geographical variation, both because they are a rare avian model
of chemical defense, and because they exhibit striking intraspecific phenotypic
variation that contradicts some aspects of our understanding of the evolution
of aposematism and mimicry. My Ph.D. research on pitohuis has involved the chemical
isolation, characterization, and quantification of defensive chemicals, and
studies of species targetted by defense (parasites and predators).
At the National Zoological Park, I am currently working on a molecular phylogeny for the genus Pitohui and other genera in the avian family Pachycephalidae. This work hopes to understand Pitohui chemical defense in a phylogenetic and biogeographical context. Because of my interest in avian systematics and New Guinean phylogeography, I have also recently been working on a collaborative project to unravel relationships within the Owlet-nightjars (genus Aegotheles) and among Aegotheles and other Caprimulgid families.
I am currently working
on two new projects. The first project is being done in collaboration with Scott
Derrickson (SI Conservation and Research Center at Front Royal, VA), John Daly
and Thomas Spande (Laboratory of Bioorganic Chemistry, NIDDK, National Institutes
of Health), and Frank Bonaccorso (Papua New Guinea National Museum and Art Gallery.)
Together, we are organizing a field and laboratory study of the physiology and
ecology of Hooded Pitohuis in New Guinea. We hope to radiotrack wild pitohuis,
study their diet, mating habits, and home range needs. We hope to bring ten
Hooded Pitohuis into captivity at the National Zoo, and here we will study whether
the pitohuis can produce toxins de novo or if they primarily sequester toxins
from their diet.
In collaboration with Andy Mack (Conservation International), Frank Bonaccorso (Papua New Guinea National Museum and Art Gallery) and Rob Fleischer (Genetics Program, National Museum of Natural History), we hope to study the avian phylogeography of Papua New Guinea using molecular techniques. We hope to use molecular data to gather evidence for and to roughly date the geological events that were most important in shaping the current distribution of birds species throughout the Papua New Guinea lowlands. The information that we gain will be important to understanding species diversity and distributions, and we hope it will be useful for conservation decisions makers.
Education: Ph.D. Ecology and Evolution, University of Chicago
M.S. Ecology and Evolution, University of Chicago
B.S. General Biology, Vanderbilt University
Original Papers:
1. J. P. Dumbacher and R. C. Fleischer. 2001. Phylogenetic evidence for colour-pattern convergence in toxic pitohuis: Müllerian mimicry in birds? Proceedings of the Royal Society of London: Biology, 268: 1971-1976.
2. L. Shapiro and J. P. Dumbacher. 2001. Adenylate kinase intron 5: A new nuclear locus for avian systematics. The Auk, 118(1): 248-255.
3. J. P. Dumbacher, T. Spande, and J. W. Daly. 2000. Batrachotoxin alkaloids from passerine birds: A second toxic bird genus (Ifrita kowaldi). Proc. Natl. Acad. Sci. USA, 97(24): 12970–12975.
4. J. P. Dumbacher. 1999. The evolution of toxicity in Pitohuis: I. Effects of homobatrachotoxin on chewing lice (Order Phthiraptera). The Auk 116(4): 957-963.
5. R. Visnak and J. P. Dumbacher. 1999. Comparison of four fumigants for removing avian lice. Journal of Field Ornithology, 70(1): 42-48.
6. J. P. Dumbacher. 1997. The ecology and evolution of chemical defense in the avian genus Pitohui. Ph.D. Thesis. University of Chicago.
7. J. P. Dumbacher and S. Pruett-Jones. 1996. Avian chemical defense. Current Ornithology, 13: 137-174.
8. B. M. Beehler and J. P. Dumbacher. 1996. More examples of fruiting trees visited predominantly by birds of paradise. Emu, 96: 81-88.
9. J. P. Dumbacher, B. M. Beehler, T. F. Spande, H. M. Garraffo, and J. W. Daly. 1993. Pitohui: How toxic and to whom? Science, 259: 582-583.
10. J. P. Dumbacher, B. M. Beehler, T. F. Spande, H. M. Garraffo, and J. W. Daly. 1992. Homobatrachotoxin in the genus Pitohui: Chemical defense in birds? Science, 258: 799-801.
11. J. P. Dumbacher. 1991. Bird life of Kagi, Central Province. Muruk (Journal of the Papua New Guinea Bird Society), 5(1): 19-21.
12. B. M. Beehler and J. P. Dumbacher. 1990. Interesting observations of birds at Varirata National Park, June - July 1990. Muruk, 4(3): 111.
Abstracts:
13. J. P. Dumbacher. 1994. Chemical defense in New Guinean birds. Journal für Ornithologie 135(3): 407.
14. J. W. Daly and J. P. Dumbacher. 1994. Alkaloids as a chemical defense in birds. Journal für Ornithologie 135(3): 408.
Book Reviews:
15. J. P. Dumbacher. 1991. [review of] The Ruff, by Johan G. Van Rhijn. The Auk 108(4): 1007.
16. J. P. Dumbacher. 1991. [review of] Social, Sexual, and Pseudosexual Behavior of the Blue-bellied Roller, Coracias cyanogaster: The Consequences of Crowding or Concentration, by Martin Moynihan. Auk 108(2): 457.
Revision: October 2001