1. Thermal performance curves (TPCs) are commonly used to forecast species’ responses to temperature change. Recent work has demonstrated that the breadth and shape of a consumer’s TPC change with resource densities, highlighting the potential for inaccurate forecasts if resource densities are not static. In particular, if resource densities decline, the optimal temperature and breadth of thermal performance also declines leading to an enhanced risk of warming, particularly among species that may incur additional costs of behavioral thermoregulation. 2. Here, we investigate the relationship between resource density and temperature (warming) on the persistence of a consumer population which exerts top-down control on its resource via trophic interaction. Trophic coupling generally reduces the potential for resource declines to exacerbate the negative effects of warming on consumers; when warming has negative effects on the consumer, resource densities tend to increase due to a reduction in top-down control. However, if resources are more sensitive to warming (e.g. due to an asymmetry amongst their thermal performance curves), the negative effects of warming on consumers can be exacerbated by declining resources. 3. Our work elucidates the importance of jointly considering temperature and resource limitation when utilizing assessing the thermal performance of species. We demonstrate how knowledge of the thermal performance of a resource population can be used to generate realized consumer thermal performance curves.

1) As temperatures rise across the globe, many species may approach or even surpass their physiological tolerance to withstand high temperatures. Thermal performance curves, which depict how vital rates vary with temperature, are often measured under ideal laboratory conditions and then used to determine the physiological or demographic limits of persistence. However, this approach fails to consider how interactions with other factors (e.g. resources, water availability) may buffer or magnify the effect of temperature change. Recent work has demonstrated that the breadth and shape of a consumer’s thermal performance curve change with resource densities, highlighting the potential for temperature interactions and leading to a potential ‘metabolic meltdown’ when resources decline during warming (Huey and Kingsolver 2019). 2) Here, we further develop the basis for the interaction between temperature and resource density on thermal performance, persistence, and population dynamics by analyzing consumer-resource dynamic models. We find that the coupling of consumer and resource dynamics relaxes the potential for metabolic meltdown because a reduction in top-down control of resources occurs as consumers approach the limits of their thermal niche. However, when both consumers and resources have vital rates that depend on temperature, asymmetry between their responses can generate the necessary conditions for metabolic meltdown. 3) Moreover, we define the concept of a ‘realized’ thermal performance curve that takes into account the dynamic interaction between consumers, resources and temperature, and we describe an important role for this concept moving forward. 4) Synthesis. A better understanding of the link between temperature change, species interactions, and persistence allows us to improve forecasts of community response to climate change. Our work elucidates the importance of thermal asymmetries between interacting species, and resource limitation as a key ingredient underlying realized thermal niches.