Paul A. Bartell

Paul A. Bartell

  • Associate Professor of Avian Biology
316 Animal, Veterinary and Biomedical Sciences Building
University Park, PA 16802


  • 2001, Ph.D., University of Virginia, Department of Biology, Charlottesville, VA
  • 1996, M.S., University of New Hampshire, Department of Zoology, Durham, NH
  • 1993, B.S., Hope College, Departments of Biology and Psychology, Holland, MI


Research in my lab focuses on the regulation of biological clocks in birds at the systems level. We use behavioral, molecular, and electrophysiological techniques to understand the neural and endocrine mechanisms by which these daily clocks and yearly calendars control the temporal organization of behaviors and life history stages. Current projects are broadly focused along two categories:

  • We (and others) have determined that biological clocks temporally organize pre-migratory and migratory behaviors. Currently, we seek to identify the changes in protein and gene expression that allows normally diurnal birds to become nocturnally active during migration, yet still function at a high performance level despite having very little sleep.
  • The influence of biological clocks in timing reproduction has been established, yet the proximal mechanisms by which they do so have remained elusive. Our work attempts to identify the signals that the biological clock transmits, amplifies or gates in initiating reproductive development and in maintaining reproductive viability.


  • 2013 to  Present: Associate Professor, Department of Animal Science, The Pennsylvania State University, University Park, PA
  • 2012 to 2013: Assistant Professor, Department of Poultry Science, The Pennsylvania State University, University Park, PA
  • 2007 to 2012: Assistant Professor, Department of Poultry Science, The Pennsylvania State University, University Park, PA
  • 2005 to 2007: Assistant Research Professor, Department of Biology, Texas A&M University (Mentor: Dr. Vincent Cassone)
  • 2004 to 2005: Assistant Research Scientist, Department of Biology, Texas A&M University
  • 2001 to 2003: Post-doctoral Fellow, Max Planck Institute for Ornithology, Andechs, Germany (Mentor: Dr. Eberhard Gwinner)


  • Implemented in situ hybridization and real time quantitative PCR techniques to examine molecular circadian rhythms in central and peripheral oscillators
  • Applied infrared videography for unobtrusively monitoring nocturnal behaviors in birds
  • Using behavioral studies, I determined that the control of nocturnal migratory restlessness in songbirds is under the direct control of the circadian system
  • Discovered that different neuronal structures within the avian brain undertake dramatic seasonal changes in glucose uptake and melatonin receptor density and that these structures are correlated with changes in migratory status

Selected Publications

Cassone, V. M., P. A. Bartell, B. J. Earnest, and V. Kumar. 2008. Duration of melatonin regulates seasonal changes in song control nuclei of the house sparrow, Passer domesticus: independence from gonads and circadian entrainment. J. Biol. Rhythms 23:49-58.

Bartell, P., M. Miranda-Anaya, and M. Menaker. 2007. Circadian rhythms of dopamine and melatonin in the retina of the Green Iguana. J. Biol. Rhythms. 22:515-523.

Miranda-Anaya, M., J. Corona-Lagunas, and P. A. Bartell. 2007. Seasonal effects of pinealectomy on the locomotor activity rhythm in the lizard Sceloporus torquatus . Biol. Rhythm Res. 38:87-93.

Bartell, P. , A. Moore, and V. Cassone. 2006. The photoperiodic and circadian control of nocturnal migratory restlessness in the Brown-headed Cowbird: a new model for the study of Zugunruhe. J. Ornithol. 147(suppl):66.

Bartell, P., and E. Gwinner. 2005. A separate oscillator controls nocturnal migratory restlessness in a songbird, Sylvia borin . J. Biol. Rhythms. 20:538-549.

Cassone, V. M., M. J. Bailey, S. P. Karaganis, V. Kumar and P. A. Bartell. 2005. Pineal function: clock genes and metabolic coupling. In: Avian Endocrinology pgs.11-26. P. Sharp and A. Dawson (eds).

Bartell, P., M. Miranda-Anaya, and M. Menaker. 2004. Period and phase control in a multi-oscillatory circadian system ( Iguana iguana ).

Yasuo, S., T. Yoshimura, P. Bartell, M. Iigo, E. Makino, N. Okabayashi, and S. Ebihara. 2002. Effect of melatonin administration on qPer2, qPer3, qClock gene expression in the suprachiasmatic nucleus of Japanese quail. Eur. J. Neurosci . 16:1541-1546.

Miranda-Anaya, M., P. Bartell, and M. Menaker. 2002. Circadian rhythm of ERG: the role of dopamine and melatonin. J. Biol. Rhythms. 17:526-538.

Miranda-Anaya, M., P. Bartell, S. Yamazaki, and M. Menaker. 2000. Circadian rhythm of ERG in Iguana iguana : role of the pineal. J. Biol. Rhythms 15(2):163-171.

Lepczyk, C. A., K. G. Murray, K. Winnett-Murray, P. Bartell, E. Geyer, and T. Work. 2000. Seasonal fruit preferences and digestive correlates in American Robins. The Auk 117: 709-717.