Figure 1: The Molecular Architecture of Spider Silk. Fibers of spider silk consist of proteins that contain crystalline regions separated by amorphous regions. The crystals form from regions of the protein chain that fold into structures called beta-sheets. These beta-sheets stack together to give the spider silk its tensile strength. The amorphous regions give the silk fibers ductility. Image credit: Chen-Pan Liao.
Researchers working to create synthetic spider silk speculate that the process by which the spider spins the silk may play a critical role in establishing the biomaterial’s tensile strength and ductility. Before it is extruded, silk exists in a precursor form in the silk gland. Researchers think that the key to generating synthetic spider silk with the same properties as naturally formed spider silk may be found by mimicking the structure of the silk proteins in precursor form.
Previous work suggests that the proteins that make up spider silk exist as simple micelles in the silk gland and that when spun from this form, fibers with greater-than-steel strength are formed. But researchers’ attempts to apply this insight in a laboratory setting failed to yield synthetic silk with the desired properties.
The Structure of Spider Silk Precursors
Hoping to help unravel this problem, a team of American collaborators led by Gianneschi and Holland recently provided a detailed characterization of the structure of the silk protein precursors in spider glands.3 They discovered that the silk proteins form micelles, but the micelles aren’t simple. Instead, they assemble into a complex structure comprised of a hierarchy of subdomains. Researchers also learned that when they sheared these nanoassemblies of precursor proteins, fibers formed. If they can replicate these hierarchical nanostructures in the lab, researchers believe they may be able to construct synthetic spider silk with the long-sought-after tensile strength and ductility.
Biomimetics and Bioinspiration
Attempts to find inspiration for new technology is n0t limited to spider silk. It has become rather commonplace for engineers to employ insights from arthropod biology (which includes spiders and insects) to solve engineering problems and to inspire the invention of new technologies—even technologies unlike anything found in nature. In fact, I discuss this practice in an essay I contributed for the book God and the World of Insects.
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 mimicry of designs from biology, whereas bioinspiration relies on insights from biology to guide the engineering enterprise.
The Converse Watchmaker Argument for God’s Existence
The idea that biological designs can inspire engineering and technology advances is highly provocative. It highlights the elegant designs found throughout the living realm. In the case of spider silk, design elegance is not limited to the structure of spider silk but extends to its manufacturing process as well—one that still can’t be duplicated by engineers.
The elegance of these designs makes possible a new argument for God’s existence—one I have named the converse Watchmaker argument. (For a detailed discussion see the essay I contributed to the book Building Bridges, entitled, “The Inspirational Design of DNA.”)
The argument can be stated like this: if biological designs are the work of a Creator, then these systems should be so well-designed that they can serve as engineering models for inspiring the development of new technologies. Indeed, this scenario is what scientists observe in nature. Therefore, it becomes reasonable to think that biological designs are the work of a Creator.
Biomimetics and the Challenge to the Evolutionary Paradigm
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 cobble together new ones. Evolutionary mechanisms can optimize these systems, but even then they are, in essence, still kludges.
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, whether in this universe or in any of the dimensions of the Spider-Verse.