Size matters: plasticity in metabolic scaling shows body-size may modulate responses to climate change

Nicholas Carey*, Julia D. Sigwart

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

24 Citations (Scopus)


Variability in metabolic scaling in animals, the relationship between metabolic rate (R) and body mass (M), has been a source of debate and controversy for decades. R is proportional to M-b, the precise value of b much debated, but historically considered equal in all organisms. Recent metabolic theory, however, predicts b to vary among species with ecology and metabolic level, and may also vary within species under different abiotic conditions. Under climate change, most species will experience increased temperatures, and marine organisms will experience the additional stressor of decreased seawater pH ('ocean acidification'). Responses to these environmental changes are modulated by myriad species-specific factors. Body-size is a fundamental biological parameter, but its modulating role is relatively unexplored. Here, we show that changes to metabolic scaling reveal asymmetric responses to stressors across body-size ranges; b is systematically decreased under increasing temperature in three grazing molluscs, indicating smaller individuals were more responsive to warming. Larger individuals were, however, more responsive to reduced seawater pH in low temperatures. These alterations to the allometry of metabolism highlight abiotic control of metabolic scaling, and indicate that responses to climate warming and ocean acidification may be modulated by body-size.

Original languageEnglish
Article number20140408
Number of pages4
JournalBiology Letters
Issue number8
Publication statusPublished - Aug 2014


  • metabolic scaling
  • ocean acidification
  • ecophysiology
  • metabolic allometry
  • MLB hypothesis


Dive into the research topics of 'Size matters: plasticity in metabolic scaling shows body-size may modulate responses to climate change'. Together they form a unique fingerprint.

Cite this