>>The Pseudies do all breed earlier in the year than do the sympatric Hyla, and they all have darkly-pigmented testes (presumably an adaptation to encourage spermatazoal development in cool weather). There's overlap, of course- peepers are usually still going when the grays start up- but as a generality it holds well, at least here in the east. I don't know much about the western hylids. >>



I think you missed the point. The genus Pseudacris is not defined on the basis of cold weather breeding whatsoever. All that cladists care about are clades. After they delimited a clade, then they may (or may not) try to name it as a taxon. It is not important whether this clade has anything in common at all and whether what they do have in common is meaningful or not. This is the opposite of what traditional taxonomists used to do: i.e. find a group that has something in common, for example, feathers, and then try to determine whether the group of animals that share this similarity is polyphyletic or not. If it is polyphyletic, then the taxon would be invalidated. If it is not polyphyletic, then it is a valid taxon.



>>I share your frustration with under-supported conclusions touted as fact by taxonomists, and with the silliness of many cladistic classifications. However, I don't think it is cladistic theory itself that is the problem so much as the fact that people try to use it with Linnaean nomenclature- a case of utter incompatibility.>>



Cladistics as a methodology has evolved into something even Hennig himself may no longer recognize. Hennig insisted on the use of synapomorphies, whereas currently practicing cladists rely instead on superificial similarities. That is one of the reasons why many of the morphological cladistic analyses of the recent past are being overturned by molecular data. Kluge's lumping of Calabaria, Charina and Lichanura comes readily to mind. Not only are cladistic classifications untenable, so are the results of many cladistic analyses.



>>So- all species belong to one and only one genus by Linnaean rules, and all species are derived from a common ancestor. Therefore all genera are derived from other genera. Yet cladistics does not permit paraphyly, so logically all species must belong to a single genus. The obvious solution is to allow genera to be nested- the genera Pseudacris and Acris would be within the genus Hyla, for example- but this is disallowed by Linnaean rules. The cladists have tried to get around this by concentrating on terminal taxa and pretending that ancestral species do not exist, thereby creating a taxonomy based on which species happen to still be alive. This is foolish. >>



Cladists do not pretend that ancestral species do not exist. They pretend that ancestral species automatically become extinct when new species evolve. Similarly they pretend that an old genus becomes extinct whenever a new genus arises. That is simply nuts, because there is no evolutionary mechanism that would cause an entire genus to become extinct. Since only one species may give rise to a new genus, the remaining species within the old genus has not changed, at least not enough to be named a new genus. But cladistic convention mandates that the old genus should be treated as a new daughter genus and that it be given a new name. I know of no evolutionary mechanism that would cause all of the species within a genus to evolve into a new genus. So, in effect, cladists are giving new names to taxa that have not changed and then pretend that its ancestor became extinct.



>>Clearly a new nomenclatural system is the solution. I know Phylocode has been put forth; I don't know enough about it to really evaluate it.>>



I disagree with you here. There is no need for a new nomenclatural system. There is a need for cladists to abandon their unscientific treatment of paraphyletic taxa and to stop giving new names to taxa that have not changed.

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