Nature4Nature Publications
Open access publications authored by the Nature4Nature consortium
Hydrodynamic analysis of bioinspired vortical cross-step filtration by computational modelling
S. Van Wassenbergh and S.L. Sanderson
R. Soc. Open Sci. 10: 230315 (2023)
https://doi.org/10.1098/rsos.230315
Abstract
Research on the suspension-feeding apparatus of fishes has ledrecently to the identification of novel filtration mechanismsinvolving vortices. Structures inside fish mouths form aseries of ‘backward-facing steps’ by protruding medially intothe mouth cavity. In paddlefish and basking shark mouths,porous gill rakers lie inside ‘slots’ between the protrudingbranchial arches. Vortical flows inside the slots of physicalmodels have been shown to be important for the filtrationprocess, but the complex flow patterns have not beenvisualised fully. Here we resolve the three-dimensionalhydrodynamics by computational fluid dynamics simulationof a simplified mouth cavity including realistic flowdynamics at the porous layer. We developed and validated amodelling protocol in ANSYS Fluent software that combinesa porous media model and permeability direction vectormapping. We found that vortex shape and confinement tothe medial side of the gill rakers result from flow resistanceby the porous gill raker surfaces. Anteriorly directed vorticalflow shears the porous layer in the centre of slots. Flowpatterns also indicate that slot entrances should remainunblocked, except for the posterior-most slot. This newmodelling approach will enable future design exploration offish-inspired filters.
Biomimetic models of fish gill rakers as lateral displacement arrays for particle separation
E.M. Witkop, S. Van Wassenbergh, P.D. Heideman and S.L. Sanderson
Bioinspir. Biomim. 18 (2023) 056009
https://iopscience.iop.org/article/10.1088/1748-3190/acea0e
Abstract
Ram suspension-feeding fish, such as herring, use gill rakers to separate small food particles from large water volumes while swimming forward with an open mouth. The fish gill raker function was tested using 3D-printed conical models and computational fluid dynamics simulations over a range of slot aspect ratios. Our hypothesis predicting the exit of particles based on mass flow rates, dividing streamlines (i.e. stagnation streamlines) at the slots between gill rakers, and particle size was supported by the results of experiments with physical models in a recirculating flume. Particle movement in suspension-feeding fish gill raker models was consistent with the physical principles of lateral displacement arrays (‘bump arrays’) for microfluidic and mesofluidic separation of particles by size. Although the particles were smaller than the slots between the rakers, the particles skipped over the vortical region that was generated downstream from each raker. The particles ‘bumped’ on anterior raker surfaces during posterior transport. Experiments in a recirculating flume demonstrate that the shortest distance between the dividing streamline and the raker surface preceding the slot predicts the maximum radius of a particle that will exit the model by passing through the slot. This theoretical maximum radius is analogous to the critical separation radius identified with reference to the stagnation streamlines in microfluidic and mesofluidic devices that use deterministic lateral displacement and sieve-based lateral displacement. These conclusions provide new perspectives and metrics for analyzing cross-flow and cross-step filtration in fish with applications to filtration engineering.
Biomimetic tools: insights and implications of a comprehensive analysis and classification
J. Zhang, L. Kestem, K. Wommer and K. Wanieck
Bioinspir. Biomim. 20 (2025) 026014
https://iopscience.iop.org/article/10.1088/1748-3190/adaff6
Abstract
Biomimetics as the transdisciplinary field leveraging biologically inspired solutions for technical and practical challenges has gained traction in recent decades. Despite its potential for innovation, the complexity of its process requires a deeper understanding of underlying tasks, leading to the development of various tools to aid this process. This study identified an inventory of 104 tools used in biomimetics, of which 24 have been classified as fully accessible, functional, and ready-to-use biomimetic tools. Additionally, it provides definitions and evaluation criteria for biomimetic tools, offering a structured approach to tool assessment. The 24 tools have been assessed based on ten criteria in a qualitative and quantitative analysis yielding an overview of their typology, accessibility, stage of development, and other key characteristics. Patterns of the typology development of tools over time revealed a trend towards integrating computational methods and artificial intelligence, thereby enhancing the tool’s functionality and user engagement. However, gaps in tool functionality and maturity, such as the lack of tools designed to support technical processes, the absence of tools tailored for solution-based approaches, and insufficient evidence of successful tool application, highlight areas for future research. The study results underscore the need for empirical validation of tools, and research into the effectiveness of holistic tools covering multiple stages of the biomimetic process. By addressing these gaps and leveraging existing strengths, the field of biomimetics can continue to advance, providing innovative solutions inspired by biological models.
Overlooked sources of inspiration in biomimetic research
J. Zhang, S. Baeckens, R. Van Damme and K. Wanieck
Sci Rep 15, 25590 (2025)
https://www.nature.com/articles/s41598-025-11703-6#article-info
Abstract
Biomimetics draws inspiration from biological organisms, yet only a small fraction of Earth’s biodiversity has been explored for innovation. This study examines the biological models used in biomimetic research. Using GPT-4o, we analyzed 74,359 publications and identified 31,776 biological models, revealing distinct taxonomic distribution patterns. Our findings highlight a reliance on a narrow set of animal taxa; fewer than 23% of identified models were resolved at the species level—corresponding to 1,604 species; and broad taxonomic classifications (e.g., phylum, class) were more frequently cited. Despite the rapid growth of biomimetics, the exploration of new model taxa falters. Researchers tend to focus on one model per study, potentially limiting the field’s capacity to leverage evolutionary insights. To promote diversity and innovation in biomimetics, we advocate for stronger collaboration with biologists to integrate underutilized yet well-researched taxa, specify biological inspirations at the species level to enhance evolutionary insights, and—where appropriate—incorporate multiple models, enabling the use of comparative methods.
