Phylogeny and Conservation

[Shueyi]

In a message dated 98-01-27 04:05:07 EST, Russell Seymour writes:

<<
< I have been asked to give a one hour lecture for a masters level course in
< Environmental Science entitled "Phylogeny and Conservation". Many, but not
< all, of the students are biologists by their first degrees; others are
< predominantly geographers and geologists but there is the odd
< anthropologist and social scientist thrown in - a real mixed bag! Even of
< the biologists few will have done any systematics before.
<
< I plan to briefly introduce terminology and basic principles of phylogeny
< reconstruction; a little on species concepts; the 'agony of choice' reserve
< selection procedure; and molecular markers as conservation tools. A few
> case studies will also be introduced. Some of this content will get only
< cursory attention and a full reference list will be supplied.
 __________________


I couldn't resist commenting on the idea that conservation biologists actually
develop conservation targets based on phylogeny.  While this idea generates
lots paper, especially out of the British Museum of Natural history, its
impact has been minimal.  It's essentially an academic answer to an applied
problem - how to best choose targets for conservation efforts.  Thus I'll
throw out a discussion that seems likely to generate some lively discussion on
the list.

Few conservation groups feel that a species approach to conservation is really
the most appropriate mechanism for making decisions, given the limited
resources available and the magnitude of the biodiversity crisis (Zoological
gardens are notable exceptions to this generality).  When species approaches
are used, the conservation targets are chosen based on imperilment - for
example we (in Indiana, USA) have a fairly intensive and ongoing effort that
targets the last known population of _Epioblasma o. obliquata_ the white
catspaw mussel.   But the catspaw is simply part of a larger community of
imperiled mussels at the site, and to be honest, we would be working on this
watershed even if the catspaw was not present.  The site is  a pretty good
place to conserve a high-quality example of an aquatic invertebrate community
that contains numerous species at risk.  There are other, better rivers in my
region that support richer communities of mussels, fishes, and insects, and we
work on the two additional rivers that support amazingly rich communities.
But neither of these are the best sites to conserve paddle fish (although both
have respectable populations), an imperiled and phylogenetically unique
animal.  Should we bail out of these solid systems and move to a degraded
river which happens to have a mega-population of paddle fish?  These are the
forced choices that choosing targets based not on need, but on some relatively
arbitrary criteria create.  Keep in mind that each of these projects literally
represents millions of dollars committed into the foreseeable future - three
watershed based projects is all we can afford in Indiana.

Other conservation efforts, especially in the neotropics, target ecosystem-
level targets.  The assumption is that by conserving intact ecosystems, you
get the whole biodiversity package - including those species that we know
nothing about.  Thus in Latin America, we and our partners target intact
systems that represent the complete array of habitats present on a ecoregional
basis.   As soon as you start choosing targets at the species level, you make
compromised choices about those unseen targets.  Moving back to my own back
yard,  should I spend time and money to protect Black Terns at the only site
they nest in Indiana - which happens to be a powerplant cooling pond? (Maybe).
Would it make a difference if the Black Tern represented the only taxon of
some bizarre phylogenetic lineage? (No).  What if this were the only place on
Earth to protect Black Terns? (then YES!!!).

The concept to remember is this.  Conservation resources (=$$$ and time) are
limited.  Conservation targets are almost unlimited.  If you really want to
make a difference in the World, utilize limited resources such that they
maximize conservation impact.  And you best accomplish that by conserving ALL
ecosystems (or what's left of them) on Earth.  Targeting unique phylogenetic
lineages per say, is at best a distraction from the greater task at hand.


John Shuey,
Director of Conservation Science
Indiana Office of The Nature Conservancy