John P. Dumbacher (Jack)

  • Curator and Department Chair
  • Ornithology & Mammalogy
  • PhD

Molecular Ecology

I use DNA sequence variation to reconstruct phylogenies, character evolution, and to understand phylogeographic patterns. I have used phylogenetic techniques to study the evolution of toxicity and mimicry in toxic New Guinean birds, to understand the history and relationships of rare Pacific Owlet-nightjars, and I am working on an NSF-funded project to study the lowland phylogeography of New Guinean tropical forests. We are also just starting some work on Namibian elephant-shrews with Galen Rathbun.

Ecology and Evolution of Chemical Defense in Birds

Most of my research has focused on two avian genera, Pitohui and Ifrita, which comprise seven endemic New Guinean passerine species that carry potent steroidal alkaloid neurotoxins known as batrachotoxins.  I have used a variety of field and laboratory techniques, and my ongoing research involves 1) chemical isolation, characterization, and quantification of defensive chemicals from avian genera Pitohui and Ifrita, 2) ecological studies of Pitohui parasites and predators, 3) radio-telemetry studies of Pitohui diet and home range use, and as mentioned above, 4) studies of the evolution of toxicity and Müllerian mimicry in toxic New Guinean birds.

Original Papers

Dumbacher, J.P. and B. West. 2010. Collecting Galapagos and the Pacific: How Rollo Howard Beck shaped our understanding of evolution. Proceedings of the California Academy of Sciences: Series 4, Vol. 61, Supplement II, No. 13: 211-243. (PDF)
K.P. Johnson, D.H. Clayton, J. P. Dumbacher, and R.C. Fleischer. 2010. The flight of the Passenger Pigeon: Phylogenetics and biogeographic history of an extinct species.  Molecular Phylogenetics and Evolution 51(1): 455-458. (PDF)

Dumbacher, J.P., G.K. Menon, and J.W. Daly. 2009. Skin as toxin storage organ in the endemic New Guinea genus Pitohui. Auk 126(3):520-530. (PDF)
Dumbacher, J.P., K. Deiner, L. Thompson, and R.C. Fleischer. 2008. Phylogeny of the avian genus Pitohui and the evolution of toxicity in birds. Molecular Phylogenetics and Evolution 49:774-781. (PDF)
Renner, S.C., J.H. Rappole, P.C. Rasmussen, T. Aung, M. Aung, N.M. Shwe, J.P. Dumbacher, and R.C. Fleischer. 2008. A new subspecies of Tesia olivea (Sylviidae) from Chiang Mai province, northern Thailand. Journal of Ornithology 149:439-450. (PDF)
Ishak, H.D., J.P. Dumbacher, N.L. Anderson, J.J. Keane, G. Valkiu-Nas, S.M. Haig, L.A. Tell, and R.N.M. Sehgal. 2008. Blood Parasites in Owls with Conservation Implications for the Spotted Owl (Strix occidentalis). PLoS One 3(e2304):1-9. (PDF)
Mack, A., and J.P. Dumbacher. 2007. Birds of Papua, Pages 654-688 in  A.J. Marshall and B.M. Beehler (eds.), The Ecology of Papua. Conservation International, Washington. (PDF)
Arbogast, B.S., J.P. Dumbacher, S.J. Steppan, S.P. Courtney, and L.A. Sztukowski. 2006. Evaluation of scientific information regarding Preble's Meadow Jumping Mouse. Sustainable Ecosystems Institute, Portland, Oregon. (PDF Report submitted to USFWS)
Fleischer, R.C., J.J. Kirchman, J.P. Dumbacher, L. Bevier, C. Dove, N.C. Rotzel, S.V. Edwards, M. Lammertink, K.J. Miglia, and W.S. Moore. 2006. Mid-Pleistocene divergence of Cuban and North American Ivory-billed Woodpeckers. Biology Letters 2(3):466-469. (PDF)
Topf, A.L., M.T.P. Gilbert, J.P. Dumbacher, and A.R. Hoelzel. 2005. Tracing the phylogeography of human populations in Britain based on 4th-11th century mtDNA genotypes. Molecular Biology and Evolution 23(1):152-161. (PDF)
Dumbacher, J.P. 2005. Batrachotoxin, Pages 215-217 in P. Wexler (ed.), Encyclopedia of Toxicology. Elsevier, Oxford.
Beadell, J.S., E. Gering, J. Austin, J.P. Dumbacher, M.A. Peirce, T.K. Pratt, C.A. Atkinson, and R.C. Fleischer. 2004. Prevalence and differential host-specificity of two avian blood parasite genera in the Australo-Papuan region. Molecular Ecology 13:3829-3844. (PDF)
Dumbacher, J.P., A. Wako, S.R. Derrickson, A. Samuelson, T.F. Spande, and J.W. Daly. 2004. Melyrid beetles (Choresine): A putative source for the batrachotoxin alkaloids found in poison-dart frogs and toxic passerine birds. Proceedings of the National Academy of Sciences 101(45):15857-15860. (PDF)
Courtney, S.P., J.A. Blakesley, R.E. Bigley, M.L. Cody, J.P. Dumbacher, R.C. Fleischer, A.B. Franklin, J.F. Franklin, R.J. Gutiérrez, J.M. Marzluff, and L. Sztukowski. 2004. Scientific evaluation of the status of the Northern Spotted Owl. Sustainable Ecosystems Institute, Portland, Oregon. (PDFs available here)

Dumbacher, J.P., T.K. Pratt, and R.C. Fleischer. 2003. Phylogeny of the owlet-nightjars (Aves: Aegothelidae) based on mitochondrial DNA sequence. Molecular Phylogenetics and Evolution 29:540-549. (PDF) (Nexus data matrix)

Dumbacher, J.P., 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. (PDF) (Nexus data matrix)

Shapiro, L., and J.P. Dumbacher. 2001. Adenylate kinase intron 5: A new nuclear locus for avian systematics. Auk 118(1):248-255. (Full text from BioOne)

Dumbacher, J.P., T. Spande, and J.W. Daly. 2000. Batrachotoxin alkaloids from passerine birds: A second toxic bird genus (Ifrita kowaldi). Proceedings of the National Academy of Sciences of the United States of America 97(24):12970-12975. (PDF)

Dumbacher, J.P. 1999. The evolution of toxicity in Pitohuis : I. Effects of homobatrachotoxin on chewing lice (Order Phthiraptera). Auk 116(4):957-963. (PDF – high resolution [4 Mb])  (PDF – low resolution [512 kb])
Visnak, R., and J.P. Dumbacher. 1999. Comparison of four fumigants for removing avian lice. Journal of Field Ornithology 70(1):42-48.

Dumbacher, J.P. 1997. The ecology and evolution of chemical defense in the avian genus Pitohui. Ph.D. Thesis, University of Chicago.

Dumbacher, J.P., and S. Pruett-Jones. 1996. Avian chemical defense. Current Ornithology 13:137-174. (PDF – high resolution [14 Mb]) (PDF – low resolution [1.5 Mb])
Beehler, B.M., and J.P. Dumbacher. 1996. More examples of fruiting trees visited predominantly by birds of paradise. Emu 96:81-88.

Dumbacher, J.P., B.M. Beehler, T.F. Spande, H.M. Garraffo, and J.W. Daly. 1993. Pitohui: How toxic and to whom? Science 259:582-583. (PDF)

Dumbacher, J.P., 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. (PDF)

Dumbacher, J.P. 1991. Bird life of Kagi, Central Province Muruk 5(1):19-21.

Beehler, B.M., and J.P. Dumbacher. 1990. Interesting observations of birds at Varirata National Park, June - July 1990. Muruk 4(3):111.


Front Cover Hearst Publication

CAS Special Publication: The Coral Triangle - The 2011 Hearst Philippine Biodiversity Expedition


The California Academy of Sciences is pleased to announce that 12 new members have joined the ranks of the Academy Fellows, a governing group of around 300 distinguished scientists who have made...

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The Academy, U.S. Fish and Wildlife Service and PRBO Conservation Science have teamed up to launch a live streaming web cam.