Emilio asks about subspecies. Okay, here is the technical aspect. The International Code of Zoological Nomenclature governs only three levels of taxa: species-level taxa, genus-level taxa, and family-level taxa. Within each level, names "compete for priority", that is, the oldest valid name is the correct one, regardless of rank within the level. A subspecies name can compete successfully with a species name. Species-level taxa include subspecies, species, and superspecies. Genus-level taxa include subgenera, genera, and supergenera. Family-level taxa... well, you get the idea. There are also some extra terms like "tribe" that can be tucked into the system when people are dealing with a very finely divided group like the ants. The higher taxa (orders, classes, phyla, kingdoms) are not governed by the Code, but are sort of a free-for-all that is governed by good sense and good taste. It's all voluntary, but it's like obeying the rules of a game: No one will want to play with you if you don't follow the rules. By naming a species, an author automatically names the corresponding subspecies and superspecies. For example, if Lynn Scheu named a new species of flying cowry, Coca cola Scheu, 1997, she would automatically be considered the author of Coca cola cola Scheu, 1997, even if the subspecies name were never printed or used. The subspecies has the same type specimen as the species of the same name. This becomes interesting information only when someone, let's say Jerry Brown, later names another subspecies, C. cola californiana Brown, 1998. There are similar rules for genus-level and family-level taxa. In the usual course of events, the most conspicuous or most typical subspecies of C. cola would be named first, leading to the situation that Emilio noted when he wrote about out-of-the-way subspecies being of "inferior" rank. But this isn't an ideal world, and sometimes the most common and "central" subspecies is named second. This is too bad, but there's nothing that can be done to correct the situation as long as we obey the rule of priority. The earliest valid name has priority over all junior synonyms and homonyms. As to varieties and forms, they are not recognized by the Code. That is, if you name a new form or variety in print today, no one will pay much attention to it. Of course, people were naming forms and varieties long before the Code was written, so forms and varieties named before the cutoff date of January 1, 1961 are automatically considered to be subspecies. "Forms" and "varieties" are almost interchangeable, but not quite. In a few cases, an author named forms within varieties within species, and this poses a problem. The Code solves this problem by saying that forms named within varieties are below the subspecies rank and are therefore not recognized by the Code. You can name them if you wish, and some people do, but they do not "compete for priority" or for homonymy and are not protected by the Code. Most people ignore them. Why do we bother with subspecies? The simple answer is to say that it allows a taxonomic rank below the species, and that some people find it useful occasionally to split a species up. It's enough to say that having an extra rank adds flexibility to the system. The complex answer involves significant, consistent differences between populations that don't ordinarily interbreed (but could if they were put together), geographic separation, ecologic separation, and/or temporal separation, and a lot of arguments over what to use in what group and when, and frankly I'd rather leave it to someone else. I'm going to dance instead. Andrew K. Rindsberg Geological Survey of La Bamba