Quantifying the energetic cost of food quality constraints on resting metabolism to integrate nutritional and metabolic ecology

• Published in: Ecology letters Vol. 24; no. 11; pp. 2339 - 2349
• Main Authors: Ruiz, Thomas, Koussoroplis, Apostolos‐Manuel, Danger, Michael, Aguer, Jean‐Pierre, Morel‐Desrosiers, Nicole, Bec, Alexandre, Auer, Sonya
• Format: Journal Article
• Language: English
• Published: Paris Blackwell Publishing Ltd 01-11-2021; Wiley
• Subjects: Biomass; Chemical composition; Daphnia; Diet; Ecology; Ecology, environment; Energy metabolism; Fatty acids; Food; Food availability; Food composition; Food quality; Growth rate; Life Sciences; metabolic ecology; Metabolic rate; Metabolism; nutrition; Ontogeny; Phosphorus; secondary production; Sterols; stoichiometry
• ISSN: 1461-023X; 1461-0248
• DOI: 10.1111/ele.13855

Consumer metabolism controls the energy uptake from the environment and its allocation to biomass production. In natural ecosystems, available energy in food often fails to predict biomass production which is also (co)limited by the relative availability of various dietary compounds. To date, the link between energy metabolism and the effects of food chemical composition on biomass production remains elusive. Here, we measured the resting metabolic rate (RMR) of Daphnia magna along ontogeny when undergoing various (non‐energetic) nutritional constraints. All types of dietary (co)limitations (Fatty acids, Sterols, Phosphorus) induced an increase in mass‐specific RMR up to 128% between highest and lowest quality diets. We highlight a strong negative correlation between RMR and growth rate indicating RMR as a promising predictor of consumer growth rate. We argue that quantifying the energetic cost imposed by food quality on individual RMR may constitute a common currency enabling the integration of nutritional and metabolic ecology.
Here, we measured the resting metabolic rate (RMR) of Daphnia magna along ontogeny when submitted to various (non‐energetic) nutritional constraints (Fatty acids, Sterols, Phosphorus).All types of dietary (co)limitations induced an increase in RMR up to 128% between our highest and lowest quality diets. We argue that quantifying the energetic cost imposed by food quality on individual RMR may constitute a common currency enabling the integration of nutritional and metabolic ecology.