Biology Department: David Scholnick
Education
- B. A., Biology, University of San Diego
- M. A. Biology, College of William and Mary, Virginia
- Ph.D., Animal Physiology, University of Colorado at Boulder
- Postdoctoral Research, University of Colorado at Boulder
Contact Information
Office/Lab
210/211 Strain
503-352-2727 (voice)
503-352-2933 (fax)
david.scholnick@pacificu.edu
Courses
- Biology 202: General Biology I
- Biology 470: Animal Physiology
- Biology 145: Marine biology for Non science Majors
- Biology 345: Marine Biology
The shrimp video was made by David Scholnick at Hollings Marine Laboratory while working in the Burnett laboratory. David Scholnick and Lou Burnett hold all |
Research Interests
Worldwide animals are at an increased risk of opportunistic pathogens. Elevations in temperature and increased areas of low oxygen, suggest that pathogen exposure of lower vertebrates and marine invertebrates are escalating.
The central hypothesis underlying my research is that infectious disease can compromise the respiratory systems of lower vertebrates and invertebrates and thereby limit the ability of animals to sustain and recover from normal activities.
Working with colleagues at College of Charleston's Grice Marine Laboratory and Hollings Marine Laboratory in Charleston, South Carolina, we have demonstrated that in resting animals bacterial infection can compromise normal metabolic function. Following infection, aerobic respiration rates are down regulated and lactate levels increase in resting animals.
At Pacific University my students and I will examine the relationship between host and pathogen in lower vertebrates and invertebrates during activity and recovery. Studies will be conducted using local lizards that are infected with Plasmodium-the hemoparasite that causes malaria in a wide range of vertebrates-to determine if infected lizards have limited respiratory capacity.
Many lizard populations are regularly infected with Plasmodium which is transmitted via blood sucking invertebrates. Previous research has shown that many of the physiological disruption experienced by lizards are similar to those seen in humans. Infected lizards have reduced oxygen uptake, suffer from anemia, and have reduced fat stores.
My students and I will examine the thermoregulatory ability of infected and uninfected lizards at rest and following activity. Additional studies will determine changes in metabolism, recovery, and lactate in lizards exposed to the malarial parasite.
In a separate set of experiments, penaeid shrimp that typically inhabit estuaries and regularly encounter high temperatures and low oxygen levels will be used to examine whether bacterial infection can alter anaerobic pathways. In these studies, shrimp infected with pathogenic bacteria will be exercised on small treadmills and changes in lactate, oxygen consumption, and activity monitored. These experiments will indicate whether sublethal infection can suppress normal respiratory activity and limit recovery.
The goal of these studies is to better understanding how pathogens can impact respiration and thereby disrupt metabolic pathways during activity.
Undergraduate Research
I strongly support undergraduate research at all levels and have found that involving undergraduates in research is one of the most valuable educational experiences in the sciences. In the past I have been involved in undergraduate research projects that have given rise to several publications, presentations at national meetings as well as job and graduate school opportunities .
I feel that the most effective way students can develop independent thought and creativity is through research. I encourage students interested in getting involved in research projects to talk with me about possible opportunities during the academic year and summer.
Recent Publications
(* Indicates undergraduate research student)
- Scholnick, D. A., A. E. Barabas* S. S. Cowan*. 2006. Influence of chloride on glucose export in marine crabs: Activation of glucose-6-phosphatase by chloride ion. J. Crustacean Biol. 26:510-514.
- Scholnick, D. A., K. G. Burnett and L. E. Burnett. 2006. Impact of exposure to bacteria on metabolism in the Penaeid shrimp Litopenaeus vannamei. Biological Bulletin 211:44-49.
- Petersen*, A. M., T. T. Gleeson, and D. A. Scholnick. 2003. The effect of oxygen and adenosine on the thermoregulation of lizards. Physiol. Biochem. Zool. 76:339-347.
- Burnett, L., N. Terwilliger, A. Carroll, D. Jorgensen, D. Scholnick. 2002. Respiratory and acid-base physiology of the purple sea urchin, Strongylocentrotus purpuratus, during air exposure: Presence and function of a facultative lung. Biol. Bull. 203:42-50.
- Wallert, M., J. Foster, D. Scholnick, S. Olmschnek, B. Kuehn, and J. Provost. 2001. Kinetic analysis of glucose-6-phosphatase: An investigative approach to carbohydrate metabolism and kinetics. Biochem. Mol. Biol. Ed. 29:199-203.
- Nedrow, J. A., D. A. Scholnick, and T. T. Gleeson. 2001. Roles of lactate and catecholamines in the energetics of brief locomotion in an ectothermic vertebrate. J. Comp. Physiol. B. 171:237-245.
- Scholnick, D.A. and T. T. Gleeson. 2000. Activity before exercise influences recovery metabolism in the lizard Dipsosaurus dorsalis. J. Exp. Biol. 203:1809-1815.
- Wagner, E. L., D. A. Scholnick and T. T. Gleeson. 1999. The roles of acidosis and lactate in the behavioral hypothermia of exhausted lizards. J. Exp. Biol. 202:325-331.
- Scholnick, D. A. and T. T. Gleeson. 1997. The influence of corticosterone and glucacon on metabolic recovery from exhaustive exercise in the desert iguana Dipsosaurus dorsalis. Gen. Comp. Endocrinol. 106:147-154.
