Ciaran A. S. Shaughnessy

Ph.D. Candidate

Defended, December 2019

Ph.D. Organismic and Evolutionary Biology, Univeristy of Massachusetts, 2019

M.Sc. Biological Sciences, Depaul University, 2015

B.Sc. Chemistry, The Illinois Institute of Technology, 2012

Advisor: Stephen D. McCormick

Research Interests

Much of my work can be summarized as environmental physiology. I study how animals are adapted to survive changes to their environment, such as from temperature, dissolved gasses (O2, CO2), or salinity, that can occur as a result of tidal, diurnal, and seasonal variation, or as a result of migration between two different environments. In my research, I have worked in the field and in a laboratory setting with aquatic vertebrates (fishes) and invertebrates (crustaceans) to study the organismal, cellular, and molecular mechanisms for thermal tolerance, CO2 tolerance, osmoregulation (ion and water balance), and chemoreception. One topic of environmental physiology where I have focused much of my research is on how fishes survive in vastly different salinities. Most fishes are iono- and osmo-regulators in they maintain a constant internal ion and water balance regardless whether they live in freshwater or seawater. The thin layers of cells in the gill and gut of fishes that form a barrier separating the fishes inside (blood) from its environment (water) are important epithelia across which fish can transport ions and water. Epithelia are critical junctions in the body which facilitate important physiological processes: gas exchange (human lung, fish gill), nutrient absorption (intestine), ion transport (human kidney, fish gill), as well as protection, lubrication, or secretion of hormones and fluids. In fishes, the gill epithelium is an important barrier the width of only a single cell which separates blood from the aquatic environment and is the primary site of many epithelial processes including gas exchange (O2 and CO2), ion transport (Na+ and Cl-), ammonia excretion, and acid-base balance. My dissertation research focused primarily on describing the molecular pathway for Cl- secretion across gills of the most basal extant osmoregulating vertebrate, the sea lamprey (Petromyzon marinus), as well as the endocrine program which controls osmoregulation in this ancestral vertebrate group.


Barany, A., C. A. Shaughnessy, J. Fuentes , J. M. Mancera, S. D. McCormick. (2020) Osmoregulatory role of the intestine in the sea lamprey (Petromyzon marinus). Am. J. Physiol. Regul. Integr. Comp. Physiol.

Shaughnessy, C.A., S. D. McCormick. (2020) Functional characterization and osmoregulatory role of gill Na+/K+/2Cl- cotransporter (NKCC1) in sea lamprey (Petromyzon marinus), a basal vertebrate. Am. J. Physiol. Regul. Integr. Comp. Physiol. 318: R17–R29

 *Bayse S., *C.A. Shaughnessy, A. Regish, S. D. McCormick. (2020) Upper thermal tolerance and heat shock protein response of juvenile American shad (Alosa sapidissima). Estuar. Coast. 43:182–188

Shaughnessy, C. A., McCormick, S. D. (2018) Reduced thermal tolerance during salinity acclimation in brook trout (Salvelinus fontinalis) can be rescued by prior treatment with cortisol. J. Exp. Biol. 2018:jeb.169557

Shaughnessy, C. A., Anderson, E. C., Kasparian, M., Lamontagne, J. M., Bystriansky, J. S. (2017). Survival and osmoregulation of the purple marsh crab (Sesarma reticulatum) at varying salinity and pH. Can. J. Zool. 95: 985–989

Shaughnessy, C. A., Baker, D. W., Brauner, C. J., Morgan, J. D., Bystriansky, J. S. (2015). Interaction of osmoregulatory and acid-base compensation in white sturgeon (Acipenser transmontanus) during exposure to aquatic hypercarbia and elevated salinity. J. Exp. Biol. 218: 2712-2719

* denotes equal contribution