Species

84 Species

specimens between him and other taxonomists and collectors.^163 Linnaeus hoped
that his system would enable taxonomists to list all actual species, but he also knew
that his system was articial—that is, not the pure result of studying the actual char-
acters of organisms, but also imposing an a priori scheme on them for convenience.
He hoped there would be a “natural” scheme developed on the basis of an aggrega-
tion of characters, but he was never able to do more than a partial sketch of one. In
his later work, he set up a “rational” system that allowed for there to be 3600 genera
in plants, each of which could generate species through hybridization. Although this
was supposed to be a “natural” system (one based on the closeness of resemblance
of all traits of the organisms and not just a single character), in fact he chose just
three features of plants and restricted the varieties to 60 types of each (hence 60^3  =
216,000 maximum of plant species). However, this was fragmentary and in an appen-
dix, and was not developed further.^164
In summary, Linnaeus proposed a ve-rank taxonomic system, and there were
only a set number of species possible, although later he was forced by various observa-
tions, including his own, to accept that new species could be created through hybrid-
ization. All that remains of his taxonomic enterprise now are the names and general
ranks of his system, but even this has been dramatically modied, with such groups
as tribes, sub-families, and so on being added to deal with the massive increase in
species discovered since. There are now as many as 18 ranks or more, each with
supra- and sub-ranks, in the taxonomic hierarchy that is called “Linnaean.”^165
Linnaeus distinguished between the diagnostic characters (characters) and actual
traits (notae) of organisms, but it seems not much came of this distinction. He appears
to have despaired of a natural system in his foreseeable future, and so promoted a
purely diagnostic and hence conventional taxonomy, even though he believed that
species were themselves natural, along with genera. This tension underlies much of
later taxonomy.
Strictly speaking, Linnaeus did not have a “species concept,” despite recent argu-
ments that he held to a “biological” species concept.^166 If he “had” a “concept” it was
Ray’s generative concept from seed, and merely involving generation is insufcient
to make it a reproductive isolation conception of species, which is what “biological”
implies in this context. However, it is clear that he regarded interfertility as a good
test of species.

Buffon: Degeneration, Mules, and Individuals

Georges-Louis Leclerc, Comte de Buffon (1707–1788), referred to simply as Buffon,

was one of the last naturalists with an encyclopedic knowledge of zoology. Indeed,

he effectively dened that discipline. He was a French aristocrat (a count) who

superintended the “King’s Garden” (Le Jardin du Roi, later Le Jardin des Plantes).

(^163) Müller-Wille 2003.
(^164) Linné 1787.
(^165) Cf. Mayr and Ashlock 1991. See Appendix A.
(^166) Müller-Wille and Orel 2007. Linnaeus did use interfertility as a criterion for conspecificity, but that
was neither operational nor novel at the time.