inflation is the rapid accumulation of scientific names due to
processes other than new discoveries of taxa. The main processes are
"splitting", elevation of taxa to a higher level (creating inflation at
the higher level) or taxonomic error of some sort. For a report
on the effect of the phylogenetic species concept (PSC) on taxonomic
inflation, and its implications for biodiversity studies, conservation
Origins of the term "taxonomic inflation", and its various uses today
P.-M., Bininda-Edmonds, O.R.P., Crandall, K.A., Gittleman, J.L., Mace,
G.M., Marshall, J.C., Purvis, A. (2004). The impact of species concept
on biodiversity studies. Q. Rev. Biol. 79(2): 161-179. (Surveys
inflation in the numbers of specie in 89 taxonomic revisions adopting
non-PSC and PSC species delimitation. Inflation due to the adoption of
the PSC led to an average increase in species considered valid of 48%).
1) Inflation of species due to taxonomic error (overdescription)
Used by John Alroy in: Taxonomic inflation and body mass distributions
in north american fossil mammals. Journal of Mammalogy,
84(2):431-443, 2003. Available at:
N.B. This is the only use of the phrase that came up using Web of
Knowledge/ISI (but see earlier scientific journal uses below).
Intriguing use of a dynamic equilbrium model (proposal vs.
synonymization) to estimate equilibrium value of the numbers of
species. He doesn't mention any recent upsurge in the numbers of
species considered valid (c.f. use 3), which perhaps has not happened
to the fossil taxa with which he is dealing.
See also somewhat similar use of taxonomic inflation via synonymy by P. Venu (2002), in "Current Science": http://www.ias.ac.in/currsci/apr252002/924.pdf
Another paper in the same journal critiques the "biodiversity hotspot"
for herpetofauna in Sri Lanka, and argues that this is due to
overdescription, particularly via molecular data:
Chaitra MS, Vasudevan K & Shanker K. (2004) The biodiversity
bandwagon: the splitters have it. Current Science 86 (7):
See also inflation used in this sense of synonymy, an argument for use of type specimens to avoid this:
Berendsohn, Walter G. (1998). Names, taxa, and information. Proceedings
of the Taxonomic Authority Files Workshop, Washington, DC, June 22-23: (used to
be at: http://research.calacademy.org/taf/proceedings/Berendsohn.html)
2) Inflation of rank to higher categories in systematics = taxonomic elevation
See: Alex Kaslev and Toby White's "Palaeos" site.
http://www.palaeos.com/Systematics/Linnean/Linnean.htm#inflation (dated 12 Dec 2003)
e.g. "Take the example of the brachiopod family [sic] Cranioidea (a
type of marine shelled invertebrate). As these animals are quite
distinct from other members of the phylum Brachiopoda they were given
their own superfamily Cranioidea. This then became a distinct
order - Craniida. Okay, fair enough. But then in a more
recent classification they have been raised to the rank of class, the
Craniata (containing the Craniida and two other orders, the Craniopsida
and Trimerellida) and even a sub-phylum Craniiformea. Many other
examples can be given, such as classes of micro-organisms (Protista)
raised to kingdom and superkingdom rank!"
See also: Henrik Enghoff (2004): Myriapoda. Unpublished document: http://www.zmuc.dk/EntoWeb/kursmyr.doc
3) Explosion of names due to splitting
Somewhat overlaps with above usage, because taxonomic elevation, sense
(2), almost always leads to taxonomic inflation in sense (3).
See: DJ Patterson 1999. The diversity of eukaryotes. Amer. Nat. 65, supplement:
p. S99: "Ranks and Hierarchy
The past 30 yr have seen a proliferation of phyla and kingdoms largely
among the protists. In 1964, the Society of Protozoologists created a
scheme of classification with a single phylum of protozoa (Honigberg et
al. 1964). More recent classification schemes that use ranks contain
dozens of phyla (e.g., Corliss 1984; Cavalier-Smith 1998) within a
variable number of kingdoms. This **taxonomic inflation** and the use
of different ranks in a short space of time is disquieting."
See also: Cox, C. Barry 2001. The biogeographic regions reconsidered. Journal of Biogeography, 28, 511-523.
p. 517: "A more plausible possibility is that the taxonomic diversity
of the Holarctic Kingdom has been artificially inflated. ... The low
diversity of the angiosperm flora of the Holarctic Kingdom might well
also have tempted the many northern hemisphere botanists to raise the
taxonomic rank of the taxa they studied, while the greater diversity of
the taxa in the tropics might well have discouraged such a tendency.
The suggestion that there may have been **taxonomic inflation** in
Takhtajan's data base for the Holarctic Kingdom is supported by
comparison of his figures for endemic families with those derived from
Heywood's (1978) atlas (compare columns 1 and 3 in Table 1). Although
in most of the Kingdoms Heywood's figures are half those of Takhtajan,
in the Holarctic Kingdom they are only one quarter those of Takhtajan.
All of these observations support the view that the high figure for
endemic genera (and therefore also for percentage endemicity) in the
Holarctic Kingdom is a taxonomic artefact."
See also usage by Ken Kinman discussing the explosion of higher taxa of protists,
somewhat overlapping with (2) above, because both types of taxonomic inflation
can be due to the same nomenclatural acts. (Used to be at: http://www.cmnh.org/dinoarch/2001Mar/msg00064.html)
There is also a slightly different sense of taxonomic inflation by Niklas Wahlberg
for oversplitting of butterfly genera. See: http://www.lepsys.eu
I would say that this meaning (3) has a long informal history and would
be the meaning triggered in most butterfly systematists like Niklas
Wahlberg, for example, who argues that overzealous application of
incorrect phylogenetic assumptions is at the root of the problem.
I think it is also more or less what we mean in Isaac et al. 2004, only
we mean it at the species level.
See also Mallet, J. 2002. The Taxome Project. Butterflies. Refers
specifically to the effect of the phylogenetic species concept on species inflation.
Jim Mallet, May 2004.
to J. Mallet home page
Last updated: 1 April 2002