Quo vadis biophotonics? Wearing serendipity and slow science as a badge of pride, and embracing biology

This article is a reflection on the themes of the Faraday Discussion meeting on “Biological and bio-inspired optics” held from 20 to 22 July 2020. It is a personal perspective on the nature of this field as a broad and interdisciplinary field that has led to a sound understanding of the material properties of biological nanostructured and optical materials. The article describes how the nature of the field and the themes of the conference are reflected in particular in work on the 3D bicontinuous biophotonic nanostructures known as single gyroids and in bicontinuous structures more broadly. Such single gyroid materials are found for example in the butterfly Thecla opisena, where the questions of biophotonic response, of bio-inspired optics, of the relationship between structure and function, and of the relationship between natural and synthetic realisations are closely interlinked. This multitude of facets of research on single gyroid structures reflects the beauty of the broader field of biophotonics, namely as a field that lives through embracing the serendipitous discovery of the biophotonic marvels that nature offers to us as seeds for in-depth analysis and understanding. The meandering nature of its discoveries, and the need to accept the slowness that comes from exploration of intellectually new or foreign territory, mean that the field shares some traits with biological evolution itself. Looking into the future, I consider that a closer engagement with living tissue and with the biological questions of function and formation, rather than with the materials science of biological materials, will help ensure the continuing great success of this field.

💡 Research Summary

The paper is a reflective perspective on the Faraday Discussion meeting “Biological and Bio‑inspired Optics” held virtually from 20–22 July 2020. It uses the meeting as a lens to examine the current state of biophotonics, to celebrate its interdisciplinary successes, and to argue for a shift in emphasis toward deeper biological questions.

The author first outlines the meeting’s structure: sixteen peer‑reviewed contributions were presented across four thematic sessions—(i) Optics & Photonics in Nature, (ii) Bio‑inspired Optics, (iii) The Role of Structure: Order vs. Disorder, and (iv) Natural and Synthetic Materials. The majority of talks focused on physical or materials‑science analyses of dead biological specimens (feathers, beetle cuticles, butterfly wing scales, eggshells, plant leaves, etc.). While these studies have dramatically advanced our understanding of how nanostructures produce colour, polarization, scattering, or sensing, they rarely addressed why those structures exist from an evolutionary or functional standpoint. The author notes that only a handful of presenters were biologists, underscoring the field’s current orientation as “materials science applied to biology” rather than “biology investigated with materials‑science tools.”

A central case study is the single gyroid (space group I4₁32), a three‑dimensional bicontinuous network that gives the green structural colour of the butterfly Thecla opisena. The paper reviews how the gyroid has become a model system in synthetic photonics: millimetre‑scale 3D‑printed microwave crystals, sub‑micron direct‑laser‑written polymer and glass gyroids, self‑assembled ABC triblock copolymer gyroids, and metal‑coated gyroids for visible‑range applications. In each synthetic context, researchers have mapped the optical band‑gap, chiral circular‑polarisation response, and mechanical‑optical property relationships with great precision.

Despite this progress, the author argues that the biological side remains under‑explored. The formation mechanism of the butterfly gyroid—whether it arises from plasma‑membrane folding, actin‑mediated scaffolding, or other developmental processes—has only been hinted at in electron‑microscopy studies (e.g., Ghiradella’s classic work). Recent observations of “blob‑like” gyroid precursors in Thecla opisena are intriguing but insufficient to build a comprehensive developmental model. Moreover, the evolutionary advantage of a gyroid versus a multilayer reflector or a disordered scattering structure is still speculative; the known circular‑polarisation effects appear modest, and pigment‑structure interactions are only partially understood.

The author introduces two cultural concepts: “serendipity” and “slow science.” He likens the field’s reliance on unexpected natural discoveries to the role of chance mutations in biological evolution, and he urges researchers to accept the slower, iterative pace required to unravel complex developmental pathways. This contrasts with the current trend of rapid, application‑driven publications.

Looking forward, the paper proposes two complementary strategies. First, a “biology‑centric” approach that engages living tissue, developmental biology, genetics, and high‑resolution imaging (e.g., live‑cell F‑actin tracking, cryo‑EM tomography) to directly link nanostructure formation with functional outcomes such as camouflage, mate attraction, or thermoregulation. Second, a “design‑by‑nature” pathway that systematically compares natural gyroids with synthetic analogues, using advances in simulation, machine learning, and additive manufacturing to extract design rules that can be transferred to photonic devices, sensors, or energy‑conversion materials.

In conclusion, the author asserts that biophotonics has matured into a powerful interdisciplinary field that excels at translating natural nanostructures into engineered photonic systems. However, its long‑term vitality will depend on embracing the slower, more collaborative pursuit of biological understanding—moving from “materials science applied to biology” toward “biology informing materials science.” By doing so, the community can honor the serendipitous marvels of nature while building a robust, evolution‑aware foundation for future photonic technologies.