Biological complexity and robustness

This talk will describe qualitatively in as much detail as time allows these features of biological systems and their parallels in technology, using hopefully familiar and concrete examples. The aim is to be accessible to biologists, and not to depend critically on the mathematical framework. A crucial insight is that both evolution and natural selection or engineering design must produce high robustness to uncertain environments and components in order for systems to persist. Yet this allows and even facilitates severe fragility to novel perturbations, particularly those that exploit the very mechanisms providing robustness, and this "robust yet fragile" (RYF) feature must be exploited explicitly in any theory that hopes to scale to large systems. Time permitting, the mathematical research implications will be sketched of this view of "organized complexity" in biology, technology, and mathematics. This view contrasts sharply with that of "emergent complexity" popular in other areas of science in a way that can now be made mathematically precise