Scientific illustration as a multiscale framework for representing biofilms.

Biofilms are widely recognised as a dominant mode of microbial life, yet their visual representation in the scientific literature still often relies on simplified diagrams derived from laboratory systems. While these schemes have strong pedagogical value, they do not adequately reflect the heterogeneity, structural complexity, and environmental dependence of biofilms encountered in real settings. Because visual representations shape both scientific communication and conceptualisation, the way biofilms are illustrated matters for how they are understood. Here, we present the outcome of a collaboration between a biofilm microbiologist and a scientific illustrator to develop a conceptual visual framework for representing the classical biofilm life cycle across scales and environments. Rather than replacing the classical sequence, the framework embeds it within complex microbial scenes and uses graphical guidance, including colour coding, to make its most explicit trajectory readable within heterogeneous biofilm organisation. In this way, adhesion, growth, matrix production, remodelling, and dispersal are represented not as rigidly separated stages, but as processes that may coexist locally within structured communities. To connect microscopic mechanisms with real-world situations, these processes were integrated into domestic environments such as bathrooms and kitchens. The illustrations include both undesirable and beneficial biofilms, and selected domestic biofilm structures were informed by real microscopy observations to preserve biological plausibility while maintaining graphical coherence. Particular attention was given to microbial and structural diversity across domestic habitats. The visual framework relies on isometric projection and multiscale transitions that connect experimental systems, colonised surfaces, biofilm architectures, individual cells, and extracellular matrix components within a coherent visual continuum. This approach is introduced through a progressive view extending from a laboratory flow-cell device to the molecular network surrounding cells within the biofilm. The framework was implemented across complementary media, including static figures, animated slides, a simplified movie, and a large-format poster. Together, these materials form a multiformat visual framework intended to support reasoning, teaching, and interdisciplinary communication about biofilm organisation.