It is becoming clear — with the passing of time and the ongoing progression of the climate crisis — that expectations of organism responses to climate change are not always realized. Part of this can be related to the incorporation of limited physical factors into models that predict these responses (for example, focusing on temperature but missing precipitation), or focus on the magnitude but not the timing of these factors. Part of this can be related to questions of scale (for example, whether studies consider the macroclimate versus the microclimate, or are conducted at the species, population or individual level), or the unclear role plasticity and adaptation will play, or the difficulty in factoring co-occurring impacts, such as habitat loss and pollution, into climate change projections.

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However, in addition to abiotic and environmental factors, ecologists’ ability to accurately describe the future impacts of climate change may also be hindered by difficulties in incorporating the role of biotic interactions into projections, which can change not just the magnitude but also the direction of impact.

This issue of Nature Climate Change features original research, reviews and opinions that touch on the importance of incorporating biotic connectivity into climate change ecology.

In one of two original research papers, Lesley Alton and Vanessa Kellermann show that species–species interactions can largely alter the costs of warming (see also the accompanying News & Views article by Mathieu Videlier), while in the second, Ewa Merz and colleagues reveal a negative impact of warming on network interactions and a shift in the trophic control of food webs (see also the accompanying Research Briefing). These two studies involve vastly different experimental systems and questions; Alton and Kellermann’s study investigates the metabolic cost for three Drosophila (fruit fly) species under controlled laboratory conditions, while Merz and colleagues utilize long-term monthly sampled plankton community datasets taken from Swiss lakes. Together, the works show how biotic interactions can both influence climate change outcomes and be broadly impacted by change.

The need for further research in the field is highlighted by two opinion pieces. Oswald Schmitz and colleagues’ Perspective article calls for the consideration of animals into plans for nature-based solutions, and argues that ignoring the functionally interdependent relationships between primary producers (such as trees) and animals will lead to misestimations of carbon sequestration potentials. In a separate Comment, Charlie Lowen suggests that overcoming the difficulties associated with understanding ecosystem-level change could be facilitated by the use of model ecosystems, such as lakes, which represent semi-discrete, repeated environments with clear boundaries that have well-defined and easy-to-sample food webs.

These opinion pieces underscore an issue that is well understood in the field: although it is clear that biotic interactions need to be considered as part of the understanding of climate change responses of organisms, it is also clear that doing so is an objectively difficult task.

Long-term data tracking of species–species interactions is largely absent, and collecting these data is painstakingly complex, particularly at timescales relevant to climate change. Lab experiments and the study of ‘smaller scale’ ecosystems (for example, bromeliads or microbial communities) can help with both of these issues, especially as new technology develops, but it has to be acknowledged that a search for connections will generally come as a trade-off between resolution and scale.

While global or large-scale studies can provide important information about overall patterns, smaller-scale work is needed to improve the accuracy of projections, something that is becoming increasingly important as climate change impacts intensify. The same can be said about the understanding of the other missing pieces of the puzzle that drive species shifts and survival under change, such as plasticity and adaptation, and microclimate impacts. Such work has wide-ranging implications and is urgently needed to aid management and conservation efforts.