Where Human–Animal Psychology Is Going Next: Introduction to Special Section of Commentaries

Research on human relations with other animals raises distinctive challenges for psychological science. Few other areas of psychological research are as closely tied to real-world, normalised systems of harm and institutionalised practices of animal exploitation and consumption. The implications of research in the field of human-animal relations therefore extend well beyond theory, methodological novelty, or empirical discovery. Innovative insights and new findings in this field have the potential to inform practitioners, policymakers, organisations, and animal advocates seeking to reduce animal product consumption, combat animal suffering, promote environmental sustainability, and build resilient movements and communities. Conversely, conceptual confusion, methodological weaknesses, or research that is insufficiently connected to real-world contexts may undermine these aims, rendering findings irrelevant at best, or inadvertently hindering progress at worst. As such, progress in the field depends not only on asking the right questions, but on using conceptual frameworks and methodological approaches that are suited to the complexity and real-world stakes of human attitudes and behaviour toward other animals.

This special section of Psychology of Human-Animal Intergroup Relations brings together four commentary articles that each identify a conceptual, methodological, or empirical gap that currently limits cumulative progress in the field, and in doing so constrains its practical relevance. Rather than reporting new findings or offering definitive solutions, the contributions aim to articulate conceptual problems, sharpen critical thinking, and serve as starting points for discussions and collaborations, while outlining research agendas that can support methodological robustness, theory building, and more effective translation to practice.

Origins and Overview of the Special Section

The idea for this special section emerged from the Human-Animal Relations workstream at the 10-day summer school of the European Association of Social Psychology, held in July 2025 at the University of Kent in Canterbury (UK). This was also the location of the first in-person PHAIR Animal Advocacy Conference in 2023. The workstream brought together a group of PhD researchers from diverse disciplinary and national backgrounds, alongside the authors of this introduction article, who served as instructors. The shared aim was to deepen theoretical and methodological expertise in the psychology of human-animal relations and animal product consumption. From the outset, discussions focused not only on participants’ individual research interests, but also on identifying knowledge gaps and recurring challenges that cut across projects and subfields.

A central goal was to move these discussions beyond the summer school itself and contribute more broadly to ongoing debates in the field. To this end, participants were encouraged to work collaboratively and develop one key issue into a commentary article. The four commentaries presented in this special section reflect the collective discussions that unfolded during the summer school and the independent intellectual contributions developed by the author teams.

In the first commentary, Schenk et al. (2026) address the conceptualisation and measurement of speciesism, a foundational construct in research on human-animal relations (Caviola et al., 2019; Dhont et al., 2020). Although commonly defined as discrimination based on species membership, speciesism is often considered a unitary construct despite comprising distinct manifestations, such as general beliefs about the moral worth of animals and human superiority, support for exploitative practices involving animals, and differential moral valuation of particular species. The authors argue that this conceptual ambiguity, combined with heterogeneous measurement approaches, risks a jingle fallacy in which related but non-identical constructs are treated as equivalent. By critically discussing common operationalisations, including forced-choice moral dilemmas and context-specific self-report items, the commentary calls for greater precision and transparency in aligning theoretical definitions with measurement practices.

In the second commentary, Vellana and Barnard (2026) address a longstanding challenge in psychological research: how dietary groups should be meaningfully conceptualised and categorised. They focus on two central issues: the distinction between behavioural and identity-based classifications of diet, and the trade-offs between collapsing dietary categories versus using more granular groupings. The authors argue that uncritical use of either approach risks misinterpretation of findings, reduced theoretical clarity, and limited comparability across studies. Rather than prescribing a single solution, the commentary calls for clearer theoretical justification of categorisation choices, greater precision in reporting, and more coordinated efforts to develop validated, conceptually grounded dietary classifications.

In the third commentary, de Lint et al. (2026) draw attention to the role of time in research on dietary change and attitudes toward animals, arguing that temporal dynamics remain under-theorised and under-measured in the field. They highlight how common research designs such as fixed measurement intervals, short follow-up periods, and narrow outcome assessments are often poorly suited to capturing how change unfolds (e.g., Green et al., 2026). The authors emphasise that change may occur across multiple timescales, ranging from immediate reactions to longer-term attitudinal and behavioural change, may also involve unintended aftereffects of interventions, and may follow non-linear trajectories that are obscured by conventional pre-post approaches. The commentary calls for clearer theoretical assumptions about change, alongside research designs and analytic strategies that better reflect the complexity of change processes.

In the fourth commentary, Jenni et al. (2026) turn to a pressing question for animal advocacy research and practice in the context of recent political shifts toward the right in many democracies: whether, and how, psychological research can inform efforts to engage politically conservative audiences in animal welfare initiatives despite greater potential resistance to change on the right (e.g., Ioannidou et al., 2026). The authors outline arguments for broadening the movement’s appeal, including the need for cross-party support to enact lasting policy change and to avoid animal welfare becoming entangled in polarised culture-war dynamics. At the same time, they identify potential risks, such as moral compromise, loss of authenticity among advocates, and internal movement tensions. The commentary reframes these debates as empirical questions and outlines a research agenda focused on message framing, messenger identity, and the broader consequences of strategic adaptation.

Concluding Reflections

Together, the commentaries in this special section highlight how far the field of human–animal intergroup relations has come, as well as the challenges that accompany its continued growth. By scrutinising how core constructs are defined, measured, and studied over time and across contexts, the contributions underscore that progress in the field depends not only on new findings, but on the quality of the conceptual and methodological groundwork that supports them. Importantly, this special section reflects the intellectual leadership of an impressive group of early-career scholars who are engaging critically with the tools, concepts, and research designs that will shape the field’s future. In this sense, the contributions are fundamentally optimistic as they showcase a rapidly growing field driven by a new generation of researchers who are willing to challenge conventional ways of working, confront complexity, and stimulate further dialogue and collaboration. Such efforts are essential for fostering a research culture and scientific enterprise that match the moral significance of animal suffering with appropriate scientific rigour.