Biomaterials: Properties, variation and evolution

This is an energizing time to be a biomaterials scientist and an appropriate moment to examine the state-of-the-art, current trends and future directions in biomaterials research. In nearly every area of mathematics, physics, and engineering, there is a movement toward using biology as a source of interesting questions. In addition, the tools available for materials research have progressed to where they can be usefully applied to the complex problems at the heart of biological systems. It is clear from our symposium not only that biology is reaping the benefits of this collaboration, but that there is reciprocal illumination when biology provides new systems, directions, and techniques that drive related fields forward. In this short introduction to the symposium, we will highlight some of the trends that are emerging and point out some of the larger lessons that can be drawn from the examples that were presented. To adapt Otto Schmitt’s opinion of biophysics, a symposium on biomaterials is less a focus on a single discipline than a celebration of a point of view (Harkness 2002). The studies here are odd bedfellows: they share little in terms of individual technique, focal taxon, or ecofunctional niche. However, they all take advantage of the synergy at the interface between the materials sciences and biology. Fields as disparate as surface chemistry, biology, and materials science converge in their interest in biomaterials; unfortunately, researchers in one discipline are often not aware of, or informed about, the techniques and perspectives of another. We feel this has largely been a problem of insufficient contact between different disciplines and also the (necessarily) restrictive scopes of most research programs. Investigations have focused on either proximate (e.g., nanostructural and microstructural relationships with material properties) or ultimate questions (e.g., ecological and evolutionary impacts of material variation), with the connecting flows of information inadequate to unify the levels into a broader examination of performance. We are excited to present this symposium at a time when disciplinary divisions are blurring and biomaterials researchers of strikingly different backgrounds are working toward common ends and languages. The volume of biomaterial data is reaching new critical masses, for instance, allowing us to compare material stiffnesses across tissues, from nacre to bone to cartilage, and physical science tools (such as testing techniques for nanomaterials and Finite Element Analysis) are increasingly accessible to comparative biologists. Evolutionary biologists and physiologists are collaborating with engineers and computer scientists to study skeletal stresses in biting and running, deformations in wings and fins, and gripping in toes and tails. The scales of investigation spanned by these collaborations and the ever-increasing resolution of testing and imaging techniques stretch the scope of possible questions from genetics and protein interactions up through material and organismal performance and evolution. Modern biomaterials science, then, is a flavor of systems biology—a holistic approach to examining the functions and interactions of natural materials at multiple scales and from the perspectives of multiple disciplines. It is our hope that the assemblage of topics, presented in the contexts of organismal biology and evolution, will help to broaden the often mechanistic viewpoint of materials science and promote physical science approaches to biology.