Why ‘dreaded’ and by whom? There is more than just an urge to be facetious in my title for this chapter. I have two reasons to dread the fruit fly. First, when I, and other practitioners of dynamic theories of development of my acquaintance, have tried to make some definite contact with experimental biologists, we have of course received diverse reactions from different individuals. But there have also been group characters discernible for people studying particular kinds of organism. And among the groups that I have had contact with, the very large one devoted to the fruit fly Drosophila melanogaster has seemed, particularly through the 1990s, to be one of the most difficult with which to sustain an interaction. There is, I think, a very sound reason for this, and it is much more sociological than scientific. Through the past half-century, the dynamic theory group has remained quite small, while the fruit fly group started from small beginnings and exploded to many thousands of workers, mainly seeking to identify new genes through their functions as revealed by mutations. That highly competitive and attention-absorbing field tended, I believe, to widen the gap in approaches and attitudes between molecular biologists and macroscopic-scale dynamic theorists that, for the proper advance of developmental biology, should be a shrinking gap.