Hello Tom et al: Of course there is no single answer! What this whole discussion on speciation has vividly demonstrated is the one essential concept we need to keep in mind when dealing with any classification system - it is essentially subjective. The concept of "species" is not something inherently present in living organisms, like the molecular structure of a chemical compound. Species, subspecies, families, etc. are human intellectual constructs, set up to help us deal in an efficient way with an otherwise impossibly complex mass of information. They exist as electrochemical impulses in our central nervous systems, not as objective realities in nature. If a pharmacist picks up a bottle of pills and says "is this aspirin?", he can expect an unequivocal yes or no answer. Unfortunately, some people tend to approach questions of biological classification in the same rigid way - "is this a species or isn't it?". However, this question has no simple or definitive answer because, unlike the aspirin question, it does not deal with the inate identity of something, but rather with human ideas, interpretations, and decisions regarding the position of an unbelievably complex entity within a far more complex overall scheme. Aspirin is aspirin because of it's intrinsic nature - its separation from other compounds is objectively definitive. However, a genus is a genus only because someone has created it mentally, and declared it to be a reality, thereby drawing arbitrary lines of separation between it and other similar genera. Taxonomic questions are more akin to a different question the pharmacist might ask - "where in the store should the aspirin be located?". Most would probably place it with pain relievers; others perhaps with cold and fever medications; and maybe a few would put it with blood thinners and heart medications. None of these alternatives is wrong - they are all subjective decisions based on observed objective properties of the entity being classified. Tom's example of the relocation of the genus Morum from Cassidae to Harpidae is a tough pill for me to swallow too. But the important thing to remember is that neither classification is inherently correct or incorrect - someone, after due consideration, just moved the aspirin to a different shelf. Because this is the very nature of taxonomy, there cannot be, and never will be general agreement on classification. But we could minimize our personal need for blood pressure medication by avoiding the question "is it or isn't it?", and instead just asking "where should this be placed, in view of the most reliable current opinion?". Paul M. Rhode Island