We have organized our responses first on an author-by-author basis. In some cases, a
single topic is discussed in more than one section so that we can respond directly to …

The species concept is focal in evolutionary studies and, indeed, in all biological thought. Its
endless discussion is sometimes boring and seemingly fruitless, but is not wholly futile. In …

A review. The concept of the species as a general unit for biodiversity, evolution and
taxonomy is poorly defined. There is an increasing consensus that the species category is …

Various attempts have been made at forging a species concept compatible with
phylogenetic systematics or cladistics. Several such concepts have been called the …

Our Phylogenetic Species Concept has its origin in the writings of Willi Hennig (1966) and
subsequent transformations of phylogenetic theory. Hennig recognized that the Biological …

Wheeler and Nixon (1990) belittle our analysis of the species problem (de Queiroz and
Donoghue, 1988), implying that it is merely a compilation of ideas without interpretation or …

In much of the literature in which the classification or phylogeny of an animal group is treated
the arguments for the proposed classification or phylogeny are poorly if at all dealt with. This …

I na recent undergraduate text, Ridley~ discusses no fewer than seven species concepts
(phenetic, biological, recognition, ecological, cladistic, pluralistic and evolutionary), and …

Speciation, the process through which new species come into being, is one of the central
topics of evolutionary biology. It links the great fields of micro-and macroevolutionary biology …

One major problem with L0vtrup's discussion is that he seems to confuse category and
taxon, thus confusing class and individual. This is not surprising; many previous workers …