Coexistence of phenotypic plasticity and habitat use in natural populations

When studying how individuals adapt to environmental changes, the environment is traditionally viewed as a passive backdrop, with individuals modifying their phenotype in response to environmental conditions (i.e., phenotypic plasticity). However, this perspective overlooks the active role of habitat choice in mediating individual responses to environmental changes. In this paper, we argue for the explicit inclusion of habitat use as an individual metric, which we term the ‘oikotype’, and explore its implications for understanding individual–environment interactions. We propose a conceptual framework that focuses on the patterns of among- and within-individual (co)variation between phenotype and oikotype, offering new insights into the processes that shape adaptation to changing environments. We complement this framework with a description and discussion of appropriate statistical approaches and outline how it can be extended to incorporate niche construction. Ultimately, integrating phenotypic plasticity, habitat use, and habitat modifications into a unified model is essential for understanding how organisms make decisions and adapt to a changing environment.