Understanding the diversity of life requires the study of evolutionary processes across the biological hierarchy – from molecules to ecosystems. Biomaterials are a crucial link between these levels of organization because they act as a direct interface between the molecular physiologies of organisms and their environments. We use spiders to study the interactions that have occurred between silk genes, the physiological production and biomechanics of silk, and the ecological functions of silks during the 400 million year evolutionary diversification of spiders and their silk "toolkits". of this “biological super-material”.
A single orb spider spins seven types of silk from discrete glands, composed of proteins with unique amino acid sequences. Each silk is used for distinct ecological functions and they are incredibly divergent in properties – dragline silk is as strong as steel while capture silk is as stretchy as rubber. Spider silks ranks among the toughest (energy absorbing) materials known, yet are produced under benign conditions in living tissue. Thus, spider silk is also the subject of intense research interest and funding from materials science, the military and industry.
While our research has clear biomimetic implications, it is motivated primarily by the unique opportunity that spider silk presents to study evolutionary processes, particularly interactions between behaviors and biomaterials.