Will Invertebrates Require Increasingly Carbon-Rich Food in a Warming World?

Area of Science:

• Ecology
• Environmental Science
• Zoology

Background:

• Metabolism and respiration increase in temperature-sensitive (poikilothermic) organisms as temperatures rise.
• Invertebrate consumers may need more carbon-rich diets to meet increased energetic demands in warming environments.

Purpose of the Study:

• To test the hypothesis that invertebrates require increasingly carbon-rich diets with rising temperatures.
• To investigate how elevated temperatures affect the stoichiometric requirements of invertebrate consumers.

Main Methods:

• Utilized a new stoichiometric model with carbon (C) and nitrogen (N) as currencies.
• Analyzed the impact of temperature on invertebrate metabolic demands and dietary C:N ratios.

Main Results:

• Model predictions did not support the hypothesis; invertebrate nutritional requirements (C:N ratio) showed little change at elevated temperatures.
• Excess carbon in nutrient-limited food sources can meet increased energy demands without altering dietary C:N ratios.
• Increased feeding at elevated temperatures compensates for metabolic demands when metabolic and intake rates scale similarly with temperature.

Conclusions:

• Elevated temperatures do not necessarily increase the demand for carbon-rich diets in invertebrates.
• Future increases in the C:N ratios of autotroph biomass may worsen the stoichiometric mismatch for nutrient-limited invertebrate grazers.
• This mismatch has significant implications for carbon sequestration and nutrient cycling in ecosystems.