Session 4, Abstract 23
SCALING OF RESTING METABOLIC RATES IN CORNSNAKES (PANTHEROPHIS GUTTATUS) WITH COMPARISONS TO OTHER SNAKES VARYING IN ACTIVITY LEVELS
Alyssa D. Marian* and Emma D. Wass (Gary W. Gerald), Nebraska Wesleyan University, Dept. of Biology, 5000 St. Paul Ave., Lincoln, NE 68504
Resting metabolic rate usually scales with body mass to between the 0.67 and 1.0 power when assessing the relationship with a power function (R = aMb). For many animals, this relationship tends to not be significantly different from ¾. It has been suggested that when b is closer to 0.67, maintenance costs are higher and b is more limited by the movement of resources across body surfaces. When b is closer to 1.0, maintenance costs are lower and energetic demands of tissues drive the scaling relationship. Moreover, b has been shown to be negatively correlated with the metabolic coefficient or level (L) for resting metabolic rates in a variety of animals. However, data on limbless animals is somewhat scarce. Here, we examined the allometric scaling of resting metabolic rate in cornsnakes (Pantherophis guttatus) (N = 27) to compare the relationships with other species and assess the influence of activity level on both b and L. Combining our data with that collected on other snake species, we examined the hypothesis that b and L are inversely related in snakes, as has been shown in other animals. Conversely, we found that b and L were positively correlated in snakes and that snakes exhibiting more active lifestyles possess lower b and L. It is unclear why snakes differ from other animals. We hypothesize that snake body shape (mass relative to length) or the high-energy requirement needed to digest larger meals could be contributing factors to this puzzling relationship.