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Unformatted text preview: omists, who
p eddle an inherently unstable product. Their attitude is often
a p ragmatic “let’s just have a set of names that everyone can
a gree on, so we can get on with protecting what we know is
t here anyway.” Even taxonomists can sympathize with such
s entiments; and it is unfortunate indeed that their subjects, as
t he products of complex and untidy evolutionary processes,
d o not always compress easily within neat species boundaries.
B ut regrettable as it may be, this messy reality is also unavoid able – even though, because of their understandable frustra tion, those involved in conservation seem at times to have
f elt impelled to import their own imperatives into taxonomy.
If a species occurs uniquely at a particular site, that site
m ight rise in the priority list for protection; and certainly in
p urely pragmatic terms it might be easier to raise funds for a p articular locality possessing its own ‘flagship’ species. A
c onservationist might well be tempted to believe that, if this
p erceived advantage has to be gained by promoting what had
p reviously been a subspecies to full species status, then so
b e it. But then again, if that advantage were to come at the
e xpense of other sites depending on the same funding pool,
l ocal conservation gain of this kind might actually lead to a
m isallocation of resources on a wider scale. What is more,
v iewing species as irreducible units might in fact produce
d efined species populations that are simply too small to be
v iable in the long term: something that for many reasons is, at
t he very least, unfortunate from a conservation perspective.
F rom the taxonomist’s point of view, of course, this approach
m ight also lead to pressure for a biologically unsubstantiated
p roliferation of names, as one suspects may to some extent
h ave happened in Madagascar.
Fortunately, there is an alternative conservationist view of
t axonomy, one strongly advocated recently by Richard Frankham
a nd colleagues (Frankham et al. 2012). These authors argue that,
f or conservation purposes, the “substantial reproductive isola tion” required by the Differential Fitness Species Concept (DFSC:
H ausdorf 2011) is greatly preferable to the diagnosability of the P AGE 10 P hylogenetic Species Concept. Operationally the DFSC, which
i s effectively an extension of the Biological Species Concept
( BSC), is more demanding than pure diagnosability, since at
l east in the form advocated by Frankham et al. (2012) it requires
q uite extensive genetic sampling (looking widely for a dearth
o f shared alleles at one or more autosomal loci as indicators
o f a lack of gene flow). But it produces species groupings that
a re more practical to conserve because they will have larger
e ffective population sizes, and presumably wider distributions.
W hat is more, recognizing species according to the admittedly
rather imprecise criterion of substantial genetic isolation will,
t he authors claim, facilitate “genetic rescue efforts … and [when
p opulations are crosse...
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This test prep was uploaded on 03/31/2014 for the course ARH 102 taught by Professor Leslie during the Fall '08 term at SUNY Stony Brook.
- Fall '08