The Relationship between Environmental Temperature and Metabolic Rate in Endotherms and Ectotherms

Allison Baker, Abigail Arthaud, Jeremy Kaplan


We are exploring the differences in metabolic rates in endotherms and ectotherms as the environmental temperature changes.  The key impact of our research is to help pet companies to know the temperature at which the metabolic rate is the lowest without being critical so the pet will eat the least amount of food and can be shipped most efficiently.  We are attempting to figure out whether mice, Mus musculus, or crickets, Gryllus assimilis, have a lower metabolic rate at a lower temperature in order to see at what temperature the mice and crickets would eat less food.  We predict that as the temperature decreases, the metabolic rate of the ectotherm will decrease while the metabolic rate of the endotherm will increase because ectotherms rely on environmental temperature to thermoregulate while endotherms rely on cellular respiration to thermoregulate.  Other studies have focused primarily on different sizes of either endotherms or ectotherms, while we are focusing on both endotherms and ectotherms and how temperature affects each of them.  We are measuring the oxygen consumed per gram of the mice and crickets at room temperature and 10°C to compare their metabolic rate.  We will place the mice and crickets into a respiration chamber to measure their oxygen consumption at room temperature and 10°C over a period of 5 minutes to measure their metabolic rate.  The average metabolic rate for the mice at room temperature was 0.8180 O2/sec/g.  The average metabolic rate for the mice at 10°C was 0.7013 O2/g/sec.  The average metabolic rate for the crickets at room temperature was 2.0518 O2/sec/g. The average metabolic rate for the crickets at 10°C was 1.4303 O2/sec/g.


Thermoregulation, Metabolic Rate, Cellular Respiration, Ambient Temperature, Thermal Neutral Zone

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Chown, S.L., Gibbs, A.G., Hetz, S.K., Klok, C.J., Lighton, J.R.B., Marais, E., 2006. Discontinuous gas exchange in insects: a clarification of hypotheses and approaches. Physiological and Biochemical Zoology 79 (2), 333-343.

Lighton, J.R.B., 1996. Discontinuous gas exchange in insects. Annual Review Entomology 41, 309-324.

Schneiderman, H.A., 1960. Discontinuous respiration in insects: role of the spiracles. Biological Bulletin 119 (3), 494-528.

Wu, M.M., L.M. Zhou, L.D. Zhao, W.H. Zheng, J.S. Liu. 2015. Seasonal variation in body mass, body temperature and thermogenesis in the Hwamei, Garrulax canorus. Comparative Biochemistry and Physiology A Molecular and Integrative Physiology 179: 113-119

Zhao, Z.J., J. Cao, X.L. Meng, Y.B. Li. 2010. Seasonal variations in metabolism and thermoregulation in the striped hamster (Cricetulus barabensis). Journal of Thermal Biology. 35(1): 52-57.


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