Spider silks, the stuff of spider webs, are a materials engineer’s dream: they can be stronger than steel at a mere fraction of weight, and also can be tougher and more flexible. Spider silks also tend not to provoke the human immune system. Some even inhibit bacteria and fungi, making them potentially ideal for surgery and medical device applications. Exploitation of these natural marvels has been slow, due in part to the challenges involved in identifying and characterizing spider silk genes, but researchers from the Perelman School of Medicine at the University of Pennsylvania have now made a major advance with the largest-ever study of spider silk genes.