Wolfgang wrote:

Paraphyletic groups ARE artificial: you are taking a radiaiton of animals and artificialy and subjectively pruning off a few more differentiated taxa 'cos you don't like'em there.



My response:

Only Hennigians believe that paraphyletic groups are artificial. According to scientific research, the most common form of speciation is peripatric speciation. That means when a new species evolves from an old one, the old one continues to live. Hennig himself assumes otherwise. He assumes that when speciation occurs, two new species appear and the old one becomes extinct. Even Hennig himself admits that his assumption is incorrect. If the old one does not become extinct, it becomes paraphyletic since the new species must be given a new name. If the new species does not have a new name, how can one tell it apart from the old species? Similarly, when a new genus evolves, it must be given a new name to distinguish it from the old genus. The old genus is now paraphyletic because it does not include its descendant the old genus. It is thus obvious that whenever evolution occurs, paraphyletic taxa result. Unless you consider evolution to be unnatural, you cannot consider paraphyletic taxa unnatural, unless of course you are a Hennigian. That is why Darwinians consider the Hennigians' intolerance of paraphyletic taxa scientifically untenable.

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