Meeting: SICB symposium for January 2022: Causal Mechanisms of Metabolic Scaling

This project supports a symposium focused on the causal mechanisms responsible for the relationship between animal metabolic rate and body size, or metabolic scaling, to be held at the January 2022 meeting of the Society for Integrative and Comparative Biology. The symposium brings together an interdisciplinary and diverse group of senior and early-career scientists to discuss and synthesize the current understanding of this topic and to identify gaps for future investigations.

One of the most important parameters explaining the structure and function of animals is their body size. Larger animals are not just scaled-up versions of small animals. They have lower heart rates, move their limbs more slowly during running, and eat and burn less fuel per pound.

The tendency for larger animals to use less energy per pound is termed “hypometric metabolic scaling.” This size-related difference is critical for biomedical and veterinary procedures, agriculture, and ecology. For example, drug doses must be reduced in larger animals because they metabolize drugs more slowly, and scaling must be taken into account when estimating food needs of cattle and the crop consumption of locusts.

While we know how body size affects patterns in animal structure, function, and metabolism, we lack an understanding of the molecular mechanisms explaining why these patterns occur, and the symposium addresses this gap. Symposium speakers will publish at least ten manuscripts related to metabolic scaling, and will together write a synthetic paper that outlines how ecological, biomechanical, and evolutionary processes create metabolic scaling.

Development of a rigorous understanding of the evolutionary factors that drive metabolic scaling will contribute broadly to basic and applied biology.

Body size explains a large fraction of phenotypic variation in all animal groups, with many aspects of morphology, behavior, physiology, ecology, and evolution differing between small and large animals. However, biologists have a limited understanding of the causes of these scaling patterns. Of all scaling patterns, the hypometric scaling of metabolic rate has been particularly well-established, and the lower mass-specific energy turnover in larger animals is thought to drive many other observed scaling patterns such as lower mass-specific food consumption or smaller territories.

This award will fund a symposium, “Causal Mechanisms of Metabolic Scaling,” at the Society for Integrative and Comparative Biology meeting in January 2022. This will be the first symposium to focus on how natural selection acts differentially on animals of different body sizes in ways that produce interspecific metabolic scaling patterns. The symposium will encourage connections across fields, by bringing together scientists who are paleontologists, behaviorists, physiologists, biomechanists, neuroscientists, and ecologists.

This symposium will lead to the production of at least ten papers in the journal, Integrative and Comparative Biology. The speakers will also meet by zoom before and after the meeting, and in a workshop after the symposium, to prepare a synthesis paper, written collaboratively by all participants, that will synthesize the diverse perspectives that exist on metabolic scaling.

The symposium promotes inclusive scientific training by including many scientists who are early-career and/or from groups currently under-represented in science.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.