Physiological and morphological profiles vary with seasonal and cold acclimation in the freeze tolerant Cope’s gray treefrog Dryophytes chrysoscelis
Chase Jennings, Andrew Joseph Morosky, Elizabeth Evans Yokum
Dryophytes chrysoscelis possess several physiological mechanisms that contribute to their ability to be freeze tolerant which is a strategy that utilizes cryoprotectants to combat the osmotic forces that damage the cellular structure of organisms during freezing. This mechanism allows D. chrysoscelis to survive multiple cycles of freezing and thawing over the winter months. To study physiological changes induced by seasonal and cold acclimation periods, heart rate, feeding behavior, body mass, and dorsal coloration were evaluated in a laboratory setting using a protocol designed to mimic the natural reduction in temperature seen in nature. Wild-caught males were evaluated following capture in the summer and throughout the fall and winter seasons at varied temperatures and dates: August at 22°C (lab acclimated), October at 22°C (seasonal acclimated), December at 5°C and 22°C (cold acclimated and control), and January at 22°C (deacclimated). It is hypothesized that cold acclimated frogs would differ from warm acclimated frogs held at constant temperature in heart rate, body mass, feeding behavior, and dorsal coloration. Results show unique profiles at each experimental date and temperature, supporting the hypothesis that cold acclimation has a physiological impact on the measured variables. These findings also suggest that there are other, internal, mechanisms in place that contribute to the seasonal and cold acclimation response seen in D. chrysoscelis beyond the previously hypothesized temperature changes. These findings have broad implications regarding how the physiological mechanisms are regulated in organisms that exhibit freeze tolerance strategies. Our findings also contribute to the field of cryobiology, and its utilization in the field of science and medicine.
Carissa M. Krane
Primary Advisor's Department
Stander Symposium project, College of Arts and Sciences
"Physiological and morphological profiles vary with seasonal and cold acclimation in the freeze tolerant Cope’s gray treefrog Dryophytes chrysoscelis" (2022). Stander Symposium Projects. 2440.