Fig. 6. The average stress–strain behaviour presented in Fig. 4B (Araneus) and Fig. 5B (Nephila) are presented on the same axis for the purposes of direct comparison. Squares represent Nephila MA silk and circles represent Araneus MA silk. As for Figs 4 and 5, filled symbols represent values from all tests for which a value was available, and open symbols represent values from all tests that were available at that extension. The average Nephila MA silk behaviour is stiffer and the stress rises more quickly with increasing extension than is the case with Araneus MA silk.