Bacterial cellulose (BC), also known as a Kombucha mat or SCOBY, is a grown material widely adopted in design and HCI communities due to its biodegradability, accessibility and mechanical versatility. Alongside these aspects, BC's qualities to become a habitat for other living organisms, i.e., its habitabilities, have been researched in biotechnological sciences but not fully explored in design. In response to the call for biobased material alternatives and the expanding design space for multispecies interactions in HCI, in this paper, we unpack this habitability potential of BC in the design of living artefacts. Through visual storytelling we unveil our hands-on biolab journey with Komagataeibacter, the bacteria that produce BC, and show how fungi, microalgae and cyanobacteria can inhabit this material. We outline diverse options for tuning the habitabilities of BC to incite HCI designers in the creation of living artefacts that are fully grown and compatible with regenerative ecologies.

Living systems are not only characterised by the sum of individual organisms but also by the multispecies interactions that occur among them, which are crucial for self-regulation, versatility and the evolution of life. Within the fields of biodesign and biological HCI, designers and researchers have strived to facilitate and mimic the qualities that these multispecies interactions entail. However, designing in a way that can account for such intricate dynamic systems presents significant challenges, necessitating alternative approaches that offer greater nuance and sensitivity to natural ecosystems. By incorporating living organisms as interactive components within human-made systems, living artefacts provide an opportunity to explore and design with such sensitivity. Leveraging the inherent interactive potential of living organisms, we propose an ecologically oriented design approach in which living artefacts are recognised and supported within the context of an intricate web of life. To this end, we conducted an in-depth analysis of existing living artefacts, paying particular attention to the multiplicity, connectivity and reciprocity of interactions between humans, other living entities and computers. From this analysis, we identified three distinct types of multispecies interactions that help to articulate and leverage their unique features within, across and beyond living artefacts.

In recent years, there has been a notable proliferation and diversification of works in HCI, that integrate living microorganisms; an imperative lifeform dominating ecosystems of our planet. Yet despite the growing interest, there is a lack of structured lenses with which designers can strategize their processes of surfacing livingness; a material quality inherent in living artefacts with a potential to enrich user experiences and to initiate mutualistic care between humans and microorganisms. Through a systematic artefacts review and a case study on Flavobacteria, we have developed and instantiated a Taxonomy of Surfacing Livingness in Microbial Displays, consisting of six microbe-sensitive, tuneable mechanisms for human noticing of microorganisms: 1) Canvassing, 2) Marking, 3) Magnifying, 4) Translating, 5) Nudging, and 6) Molecular Programming. The taxonomy invites diverse and adaptable ways of generating and crafting microbial displays; towards overcoming microbe-specific surfacing constraints, integrating diverse stakeholders' values, and enabling nuanced address of microbial welfare.

Biodesign is an emerging form of design practice integrating biological materials and processes, and there is a growing interest in the field for structured conversations to generate insights on how it can be best taught, researched, and disseminated. In our conversations, we began exploring biodesign under the framework of Living Artefacts, in which livingness is prolonged to the use time of artefacts, and understood as a biological, ecological, and experiential phenomenon. Two researchers investigating Living Artefacts, through their short show-and-tell presentations, initiated threads of moderated open discussions. Using the Living Artefacts framework as a departure point, we collectively explored opportunities and challenges in biodesign, and possible ways in which they could be addressed.

Flavobacteria, which can be found in marine environments, are able to grow in highly organized colonies producing vivid iridescent colorations. While much is known about the biology of these organisms, their design potential as responsive media in user interfaces has not been explored. Our paper aims at bridging this gap by providing insights into the type, degree, and duration of change in Flavobacteria's expression, i.e., their living aesthetics. We present a tool to capture and characterize these changes concerning form, texture and iridescent color. To support the long-term study of their living aesthetics, we designed Flavorium. This bio-digital artifact provides the necessary habitat conditions for Flavobacteria to thrive for a month. Granting insights into the responsive behavior of this organism, this work presents a design space, vocabulary, and application concepts to inspire HCI and design scholars to investigate the complex temporal qualities of living media for future user interfaces.