SO ENDS this snippet about apoplectic marine embryologists who were horrified with Williamson’s new ideas that challenged Darwin’s idea of the pure species. The occurrence of viable hybridization has been found to occur widely in plants, to the horror of older botanists, needing a total revampt of some plant family taxonomies. Now, in invertebrates, hybridization is being widely reported as well. Hybridization is barely an evolutionary dead end.