Nature employs several strategies in fabricating high-performance materials from which scientists can garner important lessons for producing synthetic materials with enhanced properties When the mechanical properties of a single phase system are insufficient for an application, composite materials offer an important strategy to impart Increased strength and toughness By introducing nanoscale filler components, greater enhancement in mechanical function compared to traditional macro and microscale fillers is possible due to the greater surface area and lower percolation thresholds stemming from the higher aspect ratios of the nanoscale fillers In this Perspective we will discuss polymer nanocomposites drawing from the lessons of wood (network of preformed, high modulus cellulose nanorods), spider silk (self assembly of ordered domains), and tendon (hierarchical ordering)