WW:

"If a new taxonomic proposal is well supported, then academic publications will usually accept it quickly, whereas it takes a bit longer to percolate into the herpetocultural literature..."



Me:

Not so, many proposals are actually first adopted uncritically by the herpetocultural literature even though they remain controversial within academia. For example, Frost and Etheridge's arrangement of the iguanian lizards was adopted quickly by a field guide and the herpetocultural community even though many in academia prefer the old 3 family arrangement. Another example was the proposed change (on the basis of grammar) of the well known name Lampropeltis getulus to Lampropeltis getula. In both the literature (e.g. Keogh's morphological analysis of the American ratsnakes) and in personal communications with some academic herpetologists, the old name L. getulus continues to be used even though herpetocultural magazines took to the new name immediately.



WW wrote:

"Under just about any evolutionary paradigm, a species is basically a separate evolutionary lineage."



Me:

This is not so at all. According to Ernst Mayr, the most effective proponent of the BSC, a species is not a lineage.



WW:

"Most of the so-called 'species concepts' such as the BSC are in reality centered around diagnostic criteria - the BSC simply states that reproductive compatibility is the criterion for recognising species."



Me:

Again, I disagree. Organisms in nature behave in certain ways, and one of the ways they behave is to interbreed with only a relatively small number of closely related individuals. For example, birds do not interbreed with mammals, and fish do not interbreed with crocodiles, even though all of these organisms are part of the same lineage, namely Vertebrata. Further, even within a sublineage like birds or mammals, there is no interbreeding among most of the members of that sublineage. Hence it would be next to impossible to delimit a species if we choose to define species as lineages. Members of the same species do interbreed freely with each other but not with members of other species. This is what biologists observe in nature. This is how species maintain their uniqueness within a diverse biosphere. This is why the BSC is nearly universally accepted.



As verteran herpetologist H. M. Smith (1990, Herpetologica) explains:

"Refinement of the species concept in biology over the past century or so took its largest step toward fidelity to the facts of nature with the formulation denoted as the Biological Species Concept (BSC), advanced most effectively by Ernst Mayr in numerous books and articles."



WW:

"I think pretty much everyone would agree that reproductive isolation DOES indicate separate species status, since two lineages that cannot exchange genes are clearly evolving separately."



Me:

Indeed, reproductive isolation, paraphrasing Ernst Mayr, is the mechanism which is responsible for the causation and maintenance of discontinuities among contemporary living species.



WW:

"However, lack of reproductive isolation is no loger viewed as precluding separate species status by most practicing systematists nowadays, partly because of the impossibility of relevant testing for allopatric taxa."



Me:

Unfortunately many practicing systematists have gone off the deep end and they are espousing all sorts of ideological nonsense which bear no resemblance to how organisms behave in nature. Many practicing systematists have taken a huge leap backwards by embracing the typological species concepts that were once popular in the 19th century, before the modern synthesis showed how scientifically untenable typological thinking is. Unfortunately, science is not immune from fashion. Typological thinking, even though scientifically untenable, seems to be fashionable.

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