The Beatles are recognized for inspiring countless musicians and shaping the face of pop music. Likewise, beetles (the insect, not the musicians) have offered their fair share of inspiration—at least in the engineering world. The latest contribution comes from the Namib Desert beetle (Stenocara gracilipes). Using the beetle’s shell as inspiration, a team of researchers from Virginia Tech (VT) recently developed a new type of frost-free surface.1 This latest engineering advance may well translate into new types of surfaces that can reduce the cost and aggravation that arise when airplane parts, windshields, and condenser coils frost up.
This advance has ramifications for Christian apologetics by highlighting the remarkable biological designs found in nature—designs that point to a Creator’s role in orchestrating the history and the design of life.
Uninspired Attempts to Solve the Frost-Formation Problem
Frost formation on cold surfaces is a real problem. Once frost forms, getting rid of it can be quite expensive. For example, de-icing the wings of airplanes causes flight delays and requires the use of relatively large volumes of chemicals. Many engineers believe these types of problems can be sidestepped by designing frost-free surfaces.
Frost can form when water vapors condense into liquid on a surface (condensation frost). Once on the surface, the droplets eventually freeze. Thus, researchers have tried to design frost-free surfaces through the use of super-hydrophobic (water-repelling) materials. In principle, these surfaces should arrest frost formation because they prevent the condensed water droplets from serving as nucleation sites for the frosting process.
But, in practice, these super-hydrophobic surfaces don’t work. Any slight defect on the surface allows the droplet to serve as a nucleation site—and a single droplet is all that is required to frost the whole surface. Once one droplet freezes at a defect site, it will harvest water from other droplets and form ice bridges, which will cause the other droplets to freeze, and so on.
Beetle’s Design Sparks Creative Solution
With the frost-formation problem unresolved, the VT researchers turned to the surface design of Stenocara’s shell for inspiration. This remarkable beetle lives in one of the hottest places on Earth and survives by collecting water from the morning fog. An array of bumps, about 1 millimeter apart, pepper the surface of Stenocara’s back. These bumps are hydrophilic (water-attracting), but the troughs between them are coated with super-hydrophobic wax. So, when the beetle goes for a stroll on a foggy morning, water condenses on the tips of the bumps, rolls down the bumps, and flows down the hydrophobic troughs and into the beetle’s mouth.2
Inspired by Stenocara’s design, the VT researchers created a similar surface with contrasting hydrophobic and hydrophilic regions. The researchers reasoned that the hydrophilic regions would attract water, serving as a site for droplet formation—just as they do on the beetle’s back. And if the hydrophilic regions were spaced far enough apart, then ice bridges wouldn’t be able to form between the droplets, thus preventing frost formation. By testing prototypes based on this design, the VT researchers were able to demonstrate that they could, indeed, slow down the rate of frost formation and even halt it, in some instances.
The team believes that the processes used to fabricate this type of frost-free surface can be scaled up in a cost-effective way to make the surfaces commercially feasible.
Does Bioinspiration Support Evolution or Intelligent Design?
It has become rather commonplace for engineers to employ insights from insect biology to solve engineering problems and to inspire the invention of new technologies—even technologies unlike anything found in nature. This activity falls under the domain of two relatively new and exciting areas of engineering known as biomimetics and bioinspiration. As the names imply, biomimetics involves direct copying (or mimicry) of designs from biology, whereas bioinspiration relies on insights from biology to guide the engineering enterprise.
From my perspective, the use of biological designs to guide engineering efforts seems fundamentally at odds with evolutionary theory. Generally speaking, evolutionary biologists view biological systems as the products of an unguided, historically contingent process that co-opts preexisting systems to kluge together new ones. Evolutionary mechanisms can optimize these systems, but even then, they are still kluge jobs, in essence.
Given the unguided nature of evolutionary mechanisms, does it make sense for engineers to rely on biological systems to solve problems and inspire new technologies? Is it in alignment with evolutionary beliefs to build an entire subdiscipline of engineering upon mimicking biological designs? I would argue that these engineering subdisciplines do not fit with the evolutionary paradigm. On the other hand, biomimetics and bioinspiration naturally flow out of a creation model approach to biology. Using designs in nature to inspire engineering only makes sense if these designs arose from an intelligent Mind.