Chemical Turing Patterns: A Paradigm for Morphogenesis

Monday, September 14, 1998 - 1:30pm - 2:30pm
Keller 3-180
David Wollkind (Washington State University)
The development of one- and two-dimensional Turing patterns characteristic of the chlorite-iodide-malonic acid/indicator reaction occurring in an open gel continuously fed unstirred reactor is investigated by means of various weakly nonlinear stability analyses applied to the appropriately scaled governing chlorine dioxide-iodine-malonic acid/indicator reaction-diffusion model system. Then the theoretical predictions deduced from these pattern formation studies are compared with experimental evidence relevant to the diffusive instabilities under examination, which consist of stripes, rhombic arrays of rectangles, and hexagonal arrays of spots or nets, in order to explain more fully the transition to such symmetry-breaking structures when the malonic acid reservoir concentration is varied and either starch for the case of a polyacrylamide gel or the gel itself for a polyvinyl alcohol gel serves as the Turing pattern indicator.

Joint work with Laura E. Stephenson