"Nature offers a large and mostly unexplored pool of biological systems. The solutions which these systems have developed to cope with natural problems and challenges have been tested by millions of years of evolution..." - Helena Hashemi Farzaneh
What does it mean to "Identify Bio-Models"?
Once we have a list of biological functions, we can start to move into the biological space, finding organisms that do analogous things in their own environment. There are a few ways to start exploring biological models.
How do you "Identify Bio-Models"?
First, we can make use of existing bio-inspired design databases, like AskNature, which have a curated database of biological traits, classified by functional terminology useful for design (Figure 6). We can branch out further by diving into the biology literature, using databases such as Web of Science or Google Scholar. Here, search terms that include typical jargon of the field can be useful. For instance, the term “beak morphology” will yield more hits than “beak shape”. This is where collaborations with biologists can be a great benefit, as they can help identify the types of systems, traits, environments, and appropriate terminology to search for biological ideas.
At this step in the process, it is beneficial to identify a wide range of biological models to increase the chance of finding a novel strategy or a good match to the design challenge. However, with 1.5 million described species and likely over 10 million species on earth, one needs to be strategic. Here we outline several overarching strategies, which consider that evolutionary processes can be limited by past processes (“historical contingency”), available variation, and other constraints that we are not necessarily subject to as designers. First, look at how diverse organisms accomplish the same function. If unrelated organisms have evolved the same function, but followed different evolutionary paths, there is a good chance that how they accomplish this function – the underlying mechanism – varies in some way, which can provide diverse ideas for design.
Consider that a given function might play out across different “ultimate functions” (see Figure 2). For instance, while thinking about regulating temperature, we are often drawn first to organisms that live in the arctic, the desert, or other extreme climates, . temperature regulation plays a role in other life contexts. For instance, pheromone-releasing scales on butterfly wings can rapidly absorb sunlight, but this has less to do with staying warm and more to do with attracting a mate (Krishna et al 2020). With respect to parental behavior, some birds incubate their eggs by using rotting organic material, which also generates heat. (An architectural parallel might be how temperature, solar radiation, and light are inter-related.)
What is the "Research-Design Interface"?
Additional strategies that increase the biological diversity of possible design models consider the ecology and evolution of a function. Search across the “tree of life” as broadly as possible (Figure 5). The evolutionary tree of life captures the relationships of all organisms on earth, from a common single-celled ancestor to the millions of species alive today. Efforts to classify organisms (“taxonomy”) try to align classifications with evolutionary relationships, and the further apart a pair of species on the tree of life, the more likely that a given function is met through a different mechanism. Wikipedia has a handy bar on the right-hand side of organism entries that shows current classification and iNaturalist is another valuable resource.
Finally, consider the environmental context, or ecology, of the desired functions – what abiotic and biotic variables are relevant to the design challenge and what other geographic areas or ecosystems experience such conditions? For instance, in dealing with cold temperatures, consider not only Arctic environments, but also alpine environments, or night-time temperature swings in deserts. Within each type of biome or ecosystem, there are independent replicates across the globe with distinct biological communities that can provide lessons for design.
For the envelope example, we used a variety of temperature-related search words related to “how nature stays warm”, including: How does nature regulate temperature, gather heat, generate heat, capture heat, absorb heat, etc. (Figure 6). The biologists helped in selecting a range of potentially relevant models to consider in subsequent steps:
References
Krishna, A., Nie, X., Warren, A. D., Llorente-Bousquets, J. E., Briscoe, A. D., and Lee, J. 2020. Infrared Optical and Thermal Properties of Microstructures in Butterfly Wings. Proceedings of the National Academy of Sciences, 117(3), 1566-1572.