Think how nature makes things compared to how we humans make things." We talked about how animals don't just preserve the next generation; they typically preserve the environment for the ten-thousandth generation. While human industrial processes can produce Kevlar, it takes a temperature of thousands of degrees to do it, and the fiber is pulled through sulfuric acid. In contrast, a spider makes its silk - which per gram is several times stronger than steel - at room temperature in water.
William Powers, Twelve by Twelve: A One-Room Cabin Off the Grid and Beyond the American Dream
animals, environment, humans, kevlar, preservation, silk, spider, steel