CDIB and SEE Divisions
My research program is firmly rooted in comparative anatomy as an experimental science that creates natural experiments to answer specific questions. Our lab is working on a variety of vertebrate model species from lampreys to sharks, salamanders, alligators, birds, and mammals to human beings.
My research program focuses on the exploration and analysis of complex systems and the discovery of structures, constructional principles, and theoretical concepts. Examples are the discovery of the special construction of the avian hyoid suspension and its implication for the evolution of feeding adaptations in birds and mammals; the discovery of a kinetic larynx in certain birds and its fundamental role in vocalization; the discovery of the role of dermal and subcutaneous fat for the movement of feathers; the discovery of the function of the depressor feather muscles and its significance for the evolution of birds and avian flight; the development of a method of theoretical biomechanical analysis of complex skeleto-muscular systems; and the postulate that systematics and comparative anatomy are based on fundamentally distinct research programs.
I am particularly interested in the integration of individual structures and organs into mechanically coherent complex systems of interactive parts. This aspect of my research is particularly relevant to the problem of how a complex system is able to evolve without disrupting its integrity. An example is the discovery that laryngeal morphology is related to the type of hyoid suspension in birds and that, therefore, the evolutionary changes in the vocal apparatus are tied to those of the feeding apparatus in birds. A goal of my research is the reconstruction of macroevolutionary changes as a result of individual variation and natural selection based on an integration of functional-morphological and ecological data of extant organisms with paleoclimatological and geological data. An example is my long-term study of the feeding and drinking behaviors, morphology, and ecology of cockatoos and parrots, which has also implications for the evolution of the Gondwanan avifauna in general.
Homberger, D.G. Ham, K., Ogunbakin, T., Bonin, J.A., Hopkins, B.A., Osborn, M.L., Hossain, I., Barnett, H.A., Matthews II, K.L., Butler, L.G., & Bragulla, H.H. 2009. The structure of the claw sheath in the domestic cat (Felis catus): Implications for the claw shedding mechanism. Journal of Anatomy, 214: 620-643. doi: 10.1111/j.1469-7580.2009.01068.x
Bragulla, H.H. & Homberger, D.G. 2009. Structure and functions of keratin proteins in simple, stratified, keratinized and cornified epithelia - a review. Journal of Anatomy, 214: 516-559. doi: 10.1111/j.14697580.2009.01066.x
Homberger, D.G. 2003. The role of mechanical forces on the patterning of the avian feather-bearing skin: Evidence from the integumentary musculature. J. exp. Zool. (Mol. Dev. Evol.), 298B: 123-139.
Homberger, D.G. 2003. The comparative biomechanics of a prey-predator relationship: The adaptive morphologies of the feeding apparatus of Australian Black-Cockatoos and their foods as a basis for the reconstruction of the evolutionary history of the Psittaciformes. Pp. 203-228 in Vertebrate Biomechanics and Evolution (V.L. Bels, J.-P. Gasc, & A. Casinos, eds.). BIOS Scientific Publishers, Oxford.
Gudo, M. & Homberger, D.G. 2002. The functional morphology of the pectoral fin girdle of the Spiny Dogfish (Squalus acanthias): Implications for the evolutionary history of the pectoral girdle of vertebrates. Senckenbergiana lethaea, 82 (1): 241-252.
Homberger, D.G. & de Silva, K.N. 2000. Functional microanatomy of the feather-bearing avian integument: Implications for the evolution of birds and avian flight. Amer. Zool. 40 (4): 553-574.
Homberger, D.G. 1999. The avian tongue and larynx: Multiple functions in nutrition and vocalization. Pp. 94-113 in Proceedings of the 22nd International Ornithological Congress (N. Adams & R. Slotow, eds). University of Natal, Durban, South Africa. BirdLife, Johannesburg, South Africa.
Interdisciplinary Research Team
Leslie G. Butler
Daniel J. Hillmann
Kenneth (Kip) Matthews, II
Roderick H. Suthers
Thomas N. Tully