Phylogenetic diversity and nature conservation: Where are we?

Abstract

To date, there is little evidence that phylogenetic diversity has contributed to nature conservation. Here, we discuss the scientific justification of using phylogenetic diversity in conservation and the reasons for its neglect. We show that, apart from valuing the rarity and richness aspect, commonly quoted justifications based on the usage of phylogenetic diversity as a proxy for functional diversity or evolutionary potential are still based on uncertainties. We discuss how a missing guideline through the variety of phylogenetic diversity metrics and their relevance for conservation might be responsible for the hesitation to include phylogenetic diversity in conservation practice. We outline research routes that can help to ease uncertainties and bridge gaps between research and conservation with respect to phylogenetic diversity.

Full text

Phylogenetic
diversity
and
nature
conservation:
where
are
we?
Marten
Winter
1,2
,
Vincent
Devictor
3
,
and
Oliver
Schweiger
1
1
Helmholtz
Centre
for
Environmental
Research
–
UFZ,
Department
of
Community
Ecology,
Theodor-Lieser
Str.
4,
06120
Halle
(Saale),
Germany
2
German
Centre
for
Integrative
Biodiversity
Research
(iDiv),
Deutscher
Platz
5e,
04103
Leipzig,
Germany
3
Institut
des
Sciences
de
l’Evolution,
UMR
CNRS-UM2
5554,
Universite´
Montpellier
2,
Montpellier,
France
To
date,
there
is
little
evidence
that
phylogenetic
diver-
sity
has
contributed
to
nature
conservation.
Here,
we
discuss
the
scientific
justification
of
using
phylogenetic
diversity
in
conservation
and
the
reasons
for
its
neglect.
We
show
that,
apart
from
valuing
the
rarity
and
richness
aspect,
commonly
quoted
justifications
based
on
the
usage
of
phylogenetic
diversity
as
a
proxy
for
functional
diversity
or
evolutionary
potential
are
still
based
on
uncertainties.
We
discuss
how
a
missing
guideline
through
the
variety
of
phylogenetic
diversity
metrics
and
their
relevance
for
conservation
might
be
responsi-
ble
for
the
hesitation
to
include
phylogenetic
diversity
in
conservation
practice.
We
outline
research
routes
that
can
help
to
ease
uncertainties
and
bridge
gaps
between
research
and
conservation
with
respect
to
phylogenetic
diversity.
A
promising
but
yet
ambiguous
additional
biodiversity
component
for
conservation
More
than
two
decades
ago,
Richard
Vane-Wright
et
al.
[1]
proposed
phylogenetic
diversity
(see
Glossary)
as
an
addi-
tional
component
for
nature
conservation.
The
idea
was
to
integrate
information
on
the
phylogenetic
positions
of
species
as
a
legacy
of
evolutionary
processes
(e.g.,
specia-
tion,
radiation)
into
conservation
assessments
[2].
Re-
search
on
the
applicability
of
aspects
of
phylogenetic
diversity
has
steadily
increased
since
then
[3,4].
Phyloge-
netic
diversity
has
been
repeatedly
suggested
to
be
rele-
vant
for
nature
conservation
targets,
because
it
can
be
related
to
processes
such
as
extinction
[5],
biotic
invasion
[6],
ecosystem
functioning
[7],
and
even
ecosystem
services
[8].
However,
despite
the
increasing
number
of
studies,
the
scientific
proof
of
the
added
value
of
phylogenetic
diversity
for
nature
conservation
remains
weak.
We
believe
that
this
is
one
of
the
main
reasons
why
phylogenetic
diversity
is
largely
neglected
in
conservation
practice
[9,10].
Here,
we
discuss
the
relevance
and
applicability
of
considering
phy-
logenetic
diversity
in
nature
conservation.
In
addition
to
the
more
general
concept
of
conserving
all
components
of
biodiversity
because
of
their
intrinsic
values,
we
identified
four
main
conservation
approaches
that
are
commonly
proposed
as
central
justifications
for
the
conservation
of
phylogenetic
diversity:
(i)
the
rarity
aspect;
(ii)
the
richness
aspect;
(iii)
phylogenetic
diversity
as
a
proxy
for
functional
diversity;
and
(iv)
phylogenetic
diversity
as
a
proxy
for
evolutionary
potential.
Along
these
lines,
we
emphasize
that
a
sound
conceptual
justification
for
the
added
value
of
phylogenetic
diversity
is
often
missing.
We
finally
highlight
desirable
research
avenues
to
increase
our
knowledge
of
the
role
of
phylogenetic
diversity
and
of
how
it
could
potentially
improve
conser-
vation
in
the
future.
Phylogenetic
diversity
as
an
intrinsic
biodiversity
component
One
general
agreement
is
to
conserve
all
components
of
biodiversity
[11],
including
evolutionary
information.
If
we
lose
species
we
will
inevitably
lose
evolutionary
informa-
tion
[5,12].
The
concern
about
losing
evolutionary
informa-
tion
as
a
value
on
its
own
can
also
be
seen
in
the
context
of
the
general
motivation
of
nature
conservation
and
leads
to
the
fields
of
moral
and
ethical
questions.
However,
it
is
unclear
how
protecting
phylogenetic
diversity
per
se
can
be
an
ultimate
objective
for
modern
conservation
practice.
Moreover,
the
motivations
and
criteria
to
consider
phylo-
genetic
diversity
need
to
be
clearly
stated
and
scientifically
proven.
Further,
it
needs
to
be
shown
whether
current
conservation
approaches
do
or
do
not
automatically
cover
the
conservation
of
phylogenetic
diversity.
In
the
following
sections
we
discuss
these
issues
in
detail.
Opinion
Glossary
Complementarity
approach:
in
terms
of
conservation,
this
approach
uses
optimization
algorithms
to
select
a
set
of
areas
that,
if
protected,
would
represent
components
of
biodiversity
not
adequately
represented
in
existing
protected
areas
[1].
Components
could
be,
for
example,
species,
regions,
landscape
features,
evolutionary
lineages,
or
functional
characteristics.
Distinctiveness:
‘distinctiveness’
describes
the
phylogenetic
relationship
of
a
species
to
other
extant
species
regardless
of
whether
they
co-occur.
Ecological
keystone
species:
an
ecological
keystone
species
is
defined
as
a
species
that
is
exceptionally
important
for
the
structure
and
functioning
of
the
ecosystem.
Niche
conservatism:
niche
conservatism
is
a
phenomenon
where
species
ecological
niches
or
trait
characteristics
tend
to
be
unchanged
along
evolutionary
time
scales;
that
is,
between
ancestor
and
descendant.
It
is
often
characterized
by
a
significantly
higher
ecological
similarity
among
closely
related
species
than
expected
by
chance
(i.e.,
phylogenetic
signal).
Phylogenetic
diversity:
phylogenetic
diversity
is
often
referred
to
as
‘evolu-
tionary
diversity’
and
often
abbreviated
as
‘PD’.
It
is
a
commonly
used
metric
[55]
(See
Box
2
in
main
text).
Here,
we
use
phylogenetic
diversity
as
generic
term.
Phylogenetic
diversity
in
general
is
a
biodiversity
measure
based
on
evolutionary
relationships
between
species
and
represents
one
of
the
components
of
biodiversity.
Corresponding
author:
Winter,
M.
(marten.winter@ufz.de).
0169-5347/$
–
see
front
matter
ß
2012
Elsevier
Ltd.
All
rights
reserved.
http://dx.doi.org/10.1016/j.tree.2012.10.015
Trends
in
Ecology
and
Evolution,
April
2013,
Vol.
28,
No.
4
199

The
rarity
aspect
Humans
usually
value
entities
higher
when
they
are
rare.
Because
rare
species
are
often
the
first
to
become
extinct,
rare
species
in
addition
to
charismatic
and
ecological
key-
stone
species
have
received
priority
protection
[13].
The
corresponding
concept
of
rarity
in
an
evolutionary
frame-
work
is
‘phylogenetic
rarity’,
which
can
be
measured
as
uniqueness
or
phylogenetic
distinctiveness
[14].
The
ex-
tinction
of
a
species
from
a
young
and
species-rich
clade
will
result
in
a
smaller
loss
of
evolutionary
information
than
the
extinction
of
a
highly
distinct
species
from
an
old
and
species-poor
clade
(Box
1).
However,
phylogenetic
distinctiveness
is
often
correlat-
ed
with
rarity
[5,15,16]
and
the
protection
of
rare
species
will
automatically
ensure
the
conservation
of
distinct
spe-
cies.
Thus,
the
added
value
of
phylogenetic
distinctiveness
might
be
questionable.
But
at
least
two
cases
are
evident
where
phylogenetic
distinctiveness
can
help
decision
makers.
When
conservation
prioritizations
have
to
be
made
for
a
larger
number
of
rare
species,
phylogenetic
distinctiveness
can
contribute
to
the
decision
process.
That
is
what
the
EDGE
of
Existence
programme
does
[17],
identifying
species
of
particular
conservation
concern
according
to
both
rarity
and
phylogenetic
distinctiveness.
The
programme
has
already
generated
conservation
actions
for
several
different
threatened
and
evolutionarily
distinct
vertebrate
species
in
over
20
countries
worldwide
(http://www.edgeofexistence.org/).
When
information
on
the
threat
status
of
species
is
missing,
which
is
the
case
for
many
species,
phylogenetic
distinctiveness
might
help
to
guide
conservation
actions
[17–19].
For
instance,
in
the
global
International
Union
for
Conservation
of
Nature
(IUCN)
Red
List
of
amphibians,
1294
species
(22.5%)
are
not
evaluated
due
to
data
defi-
ciency
but
several
can
be
identified
as
evolutionarily
highly
distinct
[19].
According
to
these
two
cases
and
under
the
assumption
that
rarity
has
a
value
per
se,
we
see
the
application
of
phylogenetic
distinctiveness
of
single
species
as
a
promis-
ing
approach
in
improving
current
conservation
practice.
This
position
was
recently
reflected
by
the
call
for
sound
conservation
of
evolutionarily
distinct
lineages
as
an
offi-
cial
motion
at
the
last
World
Conservation
Congress
in
Korea
in
2012
[20].
The
richness
aspect
The
focus
on
single
species
has
a
long
tradition
in
nature
conservation
[17],
but
more
recent
developments
highlight
the
importance
of
considering
whole
areas
in
which
commu-
nities
and
their
ecological
processes
can
be
maintained
[1].
Traditional
area-based
conservation
often
relies
on
species
richness,
which
has
been
related
to
ecosystem
functioning
(stability,
productivity)
[21–23].
This
is
a
research
field
with
important
implications,
but
also
with
many
remaining
questions
[24]
and
difficulties
for
conservation
applications
[25].
With
these
area-based
approaches,
again
the
same
question
arises:
what
would
the
added
value
of
communi-
ty-based
phylogenetic
diversity
be
compared
with
tradition-
ally
used
measures?
For
conservation
purposes,
the
identification
of
areas
with
more
or
less
phylogenetic
diversity
than
one
would
expect
based
on
species
richness
alone
seems
to
be
impor-
tant
[26–28].
Such
an
approach
reveals
areas
with
evolu-
tionarily
very
young
or
old
clades
or
with
taxonomically
highly
clumped
or
overdispersed
communities
[29].
Forest
et
al.
[26]
showed
that
the
final
selection
of
conservation
sites
would
differ
when
the
criteria
for
selection
was
phy-
logenetic
diversity
or
species
richness.
Community-based
measures
of
phylogenetic
diversity
seem
also
particularly
suitable
when
environmental
change
affects
species
rich-
ness
differently
than
species
community
compositions
[30].
Warwick
and
Clarke
[30]
showed
a
negative
effect
of
environmental
contamination
on
the
phylogenetic
diversi-
ty
of
a
marine
community,
whereas
this
effect
was
not
reflected
by
changes
in
the
number
of
species.
Such
devia-
tions
of
evolutionary
diversity
from
expectations
based
on
the
number
of
species
have
also
been
shown
repeatedly
in
other
systems
[31,32],
which
could
make
community-based
measures
of
evolutionary
diversity
in
principle
interesting
for
nature
conservation.
But
what
would
the
added
value
of
conserving
areas
or
communities
of
unexpectedly
high
phylogenetic
diversity,
or
spending
money
on
phylogenetically
eroded
areas,
actually
be?
Unless
we
consider
the
richness
in
evolutionary
infor-
mation
as
a
value
per
se,
we
need
other
convincing
argu-
ments.
These
arguments
usually
follow
the
same
lines
as
used
for
conserving
species
richness
and
can
be
seen
in
the
context
of
conserving
ecosystem
processes
and
thus
provid-
ing
insurance
against
the
consequences
of
short-term
and
Box
1.
Phylogenetic
tree
and
distances
Phylogenetic
tree.
A
phylogenetic
tree
(Figure
I)
is
a
hypothesis
about
evolutionary
relationships
among
species
or
other
entities.
Evolu-
tionary
relationships
are
graphically
represented
by
branches
con-
necting
nodes.
An
internal
node
represents
a
hypothetical
common
ancestor
of
all
species
originating
from
that
node.
Terminal
nodes
(leaves
or
tips)
represent
observed
species
or
entities.
The
common
ancestor
of
all
other
nodes
in
the
tree
is
called
the
root.
A
clade
is
defined
as
group
of
species
with
one
single
common
ancestor
(i.e.,
a
monophyletic
group).
Branch
length.
The
length
of
a
branch
connecting
two
nodes
can
be
proportional
to
the
evolutionary
divergence
between
the
nodes.
Branch
lengths
are
mostly
based
on
temporal
divergence
(e.g.,
dated
estimates
of
divergence
times
in
geological
years,
based
on
calibrations
with
fossil
and/or
pollen
records).
Branches
Distance
Nodes
Root
Tips
Bra
nch
d
nch
es
Clade
TRENDS in Ecology & Evolution
Figure
I.
Theoretical
phylogenetic
tree
of
a
plant
community
depicting
the
most
important
tree
elements.
Opinion Trends
in
Ecology
and
Evolution
April
2013,
Vol.
28,
No.
4
200

long-term
environmental
changes.
In
the
context
of
phylo-
genetic
diversity,
common
arguments
are
to
consider
phy-
logenetic
diversity
as
a
proxy
for
functional
diversity
[33]
and
as
a
measure
of
evolutionary
potential
[26].
Phylogenetic
diversity
as
a
proxy
for
functional
diversity
It
is
argued
that
phylogenetically
distinct
species
are
likely
to
also
have
distinct
functional
traits.
For
example,
the
African
plant
Welwitschia
mirabilis
is
the
only
member
of
the
family
Welwitschiaceae.
Due
to
its
unique
combination
of
life
history
and
leaf
traits,
it
is
one
of
the
very
few
plants
able
to
survive
under
extreme
arid
conditions
and
thus
serves
as
an
important
refuge
for
many
desert
animals.
Intuitively,
the
loss
of
evolutionarily
distinct
species
is
assumed
to
constitute
an
irreversible
loss
of
functions
for
entire
ecosystems
[34].
Thus,
it
is
argued
that
preserv-
ing
a
high
level
of
phylogenetic
diversity
(and
thus
of
functional
diversity)
should
be
a
priority
target
in
conser-
vation
to
ensure
the
maintenance
of
ecological
processes
at
an
ecologically
relevant
timescale
[35].
Another
argument
for
using
phylogenetic
diversity
as
a
proxy
for
functional
diversity
is
that
comprehensive
infor-
mation
on
species
traits
is
lacking
for
most
taxa,
whereas
the
rapid
current
methodological
advances
already
provide
us
with
sufficient
evolutionary
information
for
many
taxa
[33].
To
calculate
a
robust
measure
of
functional
diversity,
a
large
amount
of
information
on
different
traits
is
needed,
which
is
often
more
intricate
than
compiling
a
phylogeny.
Thus,
it
is
often
argued
to
use
phylogenetic
diversity
as
a
proxy
for
unmeasured
functional
diversity
or
niche
dissim-
ilarity
[36,37]
instead
of
relying
on
an
uncertain
and
costly
measure
of
functional
diversity.
However,
the
generality
of
the
assumption
that
phylo-
genetic
diversity
can
indeed
be
used
as
a
proxy
for
func-
tional
diversity
is
unclear
[33]
and
has
generated
an
increasing
number
of
studies
investigating
this
relation-
ship
(e.g.,
[38]).
In
fact,
this
argument
is
still
anchored
on
the
assumption
that
closely
related
species
share
similar
traits
(phylogenetic
signal;
[39]),
whereas
the
traits
of
distantly
related
species
differ.
However,
there
are
many
examples
of
missing
or
weak
phylogenetic
signals
in
spe-
cies
traits,
suggesting
that
closely
related
species
often
do
not
share
similar
traits
[40–42].
Whether
phylogenetic
diversity
correlates
with
functional
diversity
depends
on
the
considered
traits,
the
level
of
their
phylogenetic
con-
servatism,
and
the
focal
taxa
and
regions
[7,33,39].
If
the
conservation
goal
is
to
conserve
functional
diversity,
con-
sidering
phylogenetic
diversity
might
be
either
well
suited
or
totally
misleading.
We
believe
that
this
argument
can-
not
be
used
without
reservation
to
justify
the
application
of
phylogenetic
diversity
measures
in
conservation
plans.
Phylogenetic
diversity
as
a
proxy
for
evolutionary
potential
Another
line
of
argument
considers
an
evolutionary
per-
spective
in
the
sense
of
‘evolutionary
potential’;
that
is,
species
capacities
to
evolve
in
response
to
environmental
changes
[33,43,44].
From
a
species-centered
point
of
view,
the
loss
of
phylogenetically
distinct
species
might
also
result
in
the
loss
of
evolutionary
potential,
which
is
of
particular
concern
in
the
face
of
ongoing
global
change
[45,46].
However,
despite
an
increasing
body
of
evidence
for
differences
in
the
evolutionary
potential
of
different
taxa
in
the
context
of
climate
change
[44],
diversification
on
islands
[47],
or
adaptive
radiations
[48],
it
remains
unclear
whether
the
evolutionary
potential
depends
on
the
phylo-
genetic
position
of
a
species;
that
is,
whether
it
is
a
member
of
an
old
clade
or
belongs
to
a
young
clade
that
radiated
recently
[17,33,49].
Consequently,
this
argument
cannot
be
used
for
the
consideration
of
phylogenetic
distinctiveness
in
species-centered
conservation
strategies.
From
a
community
perspective,
there
are
theoretical
studies
indicating
that
an
increase
in
phylogenetic
diver-
sity
of
a
community
increases
the
evolutionary
potential
to
adapt
to
environmental
change
[33,45,50,51].
If
one
assumes
similar
evolutionary
potential
for
closely
related
species
and
larger
differences
among
distantly
related
species,
higher
phylogenetic
diversity
within
a
community
therefore
should
increase
the
chances
of
having
some
species
or
clades
with
high
evolutionary
potential
in
the
community.
This
‘insurance
effect’
[21]
would
not
be
a
simple
effect
of
species
richness
[i.e.,
having
more
(of
similar)
species
increases
the
chances
of
having
successful
species
in
unpredictable
environments],
but
rather
an
effect
of
phylogenetic
diversity
itself.
But
as
long
as
empir-
ical
evidence
is
lacking
for
such
insurance,
spending
money
on
particular
species
or
communities
to
ensure
the
main-
tenance
of
rather
long-term
and
unknown
processes
is
hard
to
justify.
The
jungle
of
different
indices
Even
if
the
integration
of
phylogenetic
diversity
into
con-
servation
assessments
can
be
justified,
a
major
question
will
remain:
what
is
the
best
measure
and
methodological
approach
to
increase
the
conservation
benefit
compared
with
other,
more
commonly
used
conservation
measures?
Choosing
the
right
metric
of
phylogenetic
diversity
is,
in
itself,
not
an
easy
task.
There
is
a
large
variety
of
metrics
and
they
are
designed
to
quantify
different
aspects
of
phylogenetic
diversity
[52],
such
as
the
distinctiveness
of
single
species
and
whole
communities
or
phylogenetic
richness
[14,53,54]
(Box
2).
Further,
some
can
be
used
more
directly
for
priority
setting
in
conservation,
whereas
others
are
more
informative
about
the
causes
of
general
phylogenetic
diversity
patterns
(Box
2).
In
terms
of
distinctiveness
of
single
species,
metrics
such
as
taxonomic
distinctness
(TD)
[1]
and
evolutionary
distinctiveness
(ED)
[17]
were
introduced.
The
initially
purely
topology-based
indices
reflect
a
branching
order
within
a
monophyletic
group
weighted
according
to
its
distinctiveness
(number
of
nodes
to
the
tree
root;
Box
1).
Genetic
distances
and
temporal
divergence
data
are
now
increasingly
available,
making
distance-based
measures
(i.e.,
using
quantitative
branch
lengths
rather
than
num-
ber
of
nodes;
Boxes
1
and
2)
more
accurate.
Therefore,
ED
can
also
incorporate
branch
lengths
[17].
Many
of
the
community-based
indices
are
either
con-
ceptually
or
mathematically
related
or
highly
intercorre-
lated
due
to
their
dependence
on
covarying
factors
such
as
species
richness
[14,54]
(e.g.,
phylogenetic
diversity
[55])
(Box
2).
For
conservation
purposes,
phylogenetic
diversity
or
an
endemism-weighted
version
of
phylogenetic
diversity
Opinion Trends
in
Ecology
and
Evolution
April
2013,
Vol.
28,
No.
4
201

[56]
are
particularly
suited
for
a
complementarity
ap-
proach.
But
the
added
value
of
indices
that
are
mathemati-
cally
highly
dependent
on
species
richness
is
obviously
limited
unless
they
can
detect
deviations
from
the
expecta-
tions
based
on
species
richness
[26,27].
To
prevent
any
phylogenetic
diversity
metric
from
being
a
merely
modified
version
of
species
richness,
one
can
analyze
the
residuals
from
the
relationship
of
the
chosen
index
and
species
richness
[57,58]
or
apply
null
models
[42].
In
doing
so,
areas
with
unexpectedly
high
or
low
phylogenetic
diversity
can
be
identified
independent
of
the
effects
of
species
richness
[59].
However,
this
approach
is
not
free
from
arbitrary
choices
(e.g.,
the
shape
of
the
statistical
relationship
to
estimate
residuals
or
the
design
of
the
null
model
[60]).
Alternatively,
various
indices
that
are
mathematically
independent
of
species
richness
are
commonly
used
in
comparative
ecological
studies.
They
mostly
reflect
the
phylogenetic
distinctiveness
of
entire
communities,
such
as
the
Average
Taxonomic
Distinctiveness
(AvTD)
[61],
or
other
conceptually
related
measures,
such
as
Rao’s
Qua-
dratic
Entropy
[62],
the
Phylogenetic
Species
Variability
measure
(which
is
1
–
AvTD
[53]),
the
Net
Relatedness
Index,
and
the
Nearest
Taxon
Index
[36]
(Box
2).
These
indices
are
more
informative
about
causes
of
general
phy-
logenetic
diversity
patterns
and
ecological
processes
(e.g.,
community
assembly,
resistance
against
species
inva-
sions).
For
instance,
positive,
negative,
or
no
relationship
with
species
richness
can
be
interpreted
in
an
ecological
sense
[14]
(e.g.,
as
environmental
filtering
or
phylogenetic
overdispersion
[36]).
Despite
the
obvious
advantage
of
using
richness-independent
indices,
it
inevitably
leads
to
the
violation
of
set
monotonicity
[14].
In
other
words,
such
indices
can
increase
when
closely
related
species
go
ex-
tinct.
The
conservation
implications
of
using
these
indices
are
therefore
not
necessarily
straightforward.
Overall,
the
suitability
of
any
metric
for
conservation
purposes
obviously
depends
on
the
question
addressed
(e.g.,
species-based
or
community-based
approach)
and
on
the
available
data
(Box
2).
Although
bioinformatic
tools
have
been
developed
to
calculate
a
large
variety
of
phylo-
genetic
diversity
metrics
(e.g.,
[52]),
we,
however,
believe
that
conservationists
still
lack
a
comprehensive
guideline
to
determine
which
measure
is
suitable
for
which
conser-
vation
goal.
It
is
even
likely
that
research
on
the
technical
issues
related
to
metric
development
has
been
mostly
conducted
from
a
purely
academic
point
of
view
and
has
largely
failed
to
address
the
practical
needs
of
conserva-
tionists.
This
might
be
an
additional
reason
for
the
obvious
hesitation
to
include
the
evolutionary
perspective
in
na-
ture
conservation.
The
need
for
a
solid
conceptual
basis
and
reliable
guidance
If
we
accept
rarity
and
richness
to
represent
values
de-
serving
protection
on
their
own,
as
has
long
been
done
by
conservationists
for
the
species-
and
area-centered
approaches,
phylogenetic
diversity
has
the
potential
to
enrich
modern
conservation
practice.
It
can
help
by
the
identification
and
prioritization
of
species
in
need
of
pro-
tection
and
it
can
improve
the
spatial
planning
of
conser-
vation
areas
by
the
identification
of
locations
with
high
levels
of
phylogenetic
diversity
in
addition
to
species-rich
areas,
which
are
not
necessarily
congruent.
However,
in
our
opinion,
the
justification
for
preserving
phylogenetic
diversity
as
a
proxy
for
functional
diversity
or
evolutionary
potential
has
so
far
largely
failed.
Our
current
knowledge
of
the
benefits
to
the
(future)
functioning
of
ecosystems
and
securing
evolutionary
potential
remains
equivocal.
If
such
justifications
are
wanted
by
conservation-
ists
and
policymakers,
current
knowledge
will
not
convince
them
to
apply
the
concept
of
phylogenetic
diversity
because
it
still
depends
on
many
assumptions,
uncertainties,
and
varying
messages.
Without
better
justification,
pretending
that
increasing
phylogenetic
diversity
is
a
target
of
conser-
vation
interest
will
remain
highly
questionable.
Note
that
we
do
not
say
that
phylogenetic
diversity
has
no
poten-
tial
to
provide
benefits
to
nature
conservation.
But
this
can
only
be
the
case
when
it
is
well
embedded
in
a
sound
conceptual
framework
and
the
justifications
quoted
for
its
usage
are
plausible
and
verified.
This
will
be
possible
only
if
we
increase
our
understanding
of
the
relevance
of
phyloge-
netic
diversity
for
ecosystems,
what
can
be
important
for
Box
2.
Examples
of
commonly
used
metrics
to
calculate
phylogenetic
diversity
Phylogenetic
distinctiveness
of
single
species
Taxonomic
distinctiveness
(TD).
Topology
based;
species
values
are
calculated
as
the
reciprocal
of
the
number
of
nodes
between
the
species
and
the
tree
root
[1].
Evolutionary
distinctiveness
(ED).
Topology
based;
species
values
are
calculated
as
the
sum
of
values
per
branch
(tip
to
root)
[17].
The
branch
value
is
its
length
divided
by
the
number
of
descendant
species.
Phylogenetic
richness
of
communities
Phylogenetic
diversity
(PD).
Calculated
as
the
sum
of
branch
lengths
between
root
and
tips
for
a
community
[55].
PD
is
mathematically
related
to
species
richness
[14].
PD
can
be
used
as
a
complementary
measure
by
identifying
added
evolutionary
information
by
addi-
tional
species
[69].
Phylogenetic
distinctiveness
of
communities
to
explore
ecological
processes
Average
Taxonomic
Distinctiveness
(AvTD).
Calculated
as
the
sum
of
all
branch
lengths
connecting
two
species
averaged
across
all
species
representing
the
mean
distance
between
two
randomly
chosen
species
[61].
AvTD
is
independent
of
species
richness,
but
the
extinction
of
closely
related
species
will
increase
the
index.
AvTD
can
be
applied,
if
the
overall
phylogenetic
distinctiveness
within
a
community
is
of
interest,
regardless
of
any
comparison
with
other
communities.
Mean
pairwise
distance
(MPD).
MPD
and
AvTD
reflect
phylogenetic
structuring
across
the
entire
phylogenetic
tree
[70].
Mean
nearest
taxon
distance
(MNTD).
Calculated
as
the
mean
of
the
branch
lengths
connecting
each
species
to
its
closest
relative
[70].
MNTD
reflects
the
phylogenetic
structure
of
the
tips
of
the
tree.
Net
Relatedness
Index
(NRI)/Nearest
Taxon
Distance
(NTI).
Repre-
sent
the
standardized
effect
size
of
MPD
and
MNTD
accounting
for
the
effects
of
species
richness
via
repeated
random
resampling
from
a
source
pool
based
on
a
null
model
[70].
NRI
and
MPD
assess
relatedness
deeper
in
the
phylogenetic
tree
(i.e.,
an
evolutionarily
older
pattern).
NTI
and
MNTD
reflect
fine-scale
relatedness
[36,70].
Rao’s
Quadratic
Entropy
(QE).
Based
on
the
Simpson
index
and
can
account
for
abundances
[62].
Without
abundances,
QE
is
mathema-
tically
similar
to
AvTD.
Opinion Trends
in
Ecology
and
Evolution
April
2013,
Vol.
28,
No.
4
202

conservation
practice,
and
how
this
can
be
best
implemen-
ted.
In
this
respect,
we
think
the
research
agenda
on
phylo-
genetic
diversity
should
focus
on
the
following
four
main
directions.
(i)
We
still
need
a
solid
conceptual
basis
for
the
added
value
of
measures
of
phylogenetic
diversity
compared
with
the
more
traditional
measures
such
as
rarity,
threat
status,
species
richness,
and
other
existing
metrics
reflecting
the
state
of
species
and
communi-
ties.
In
particular,
we
need
to
know
under
which
conditions
a
clear
link
between
phylogenetic
diversity
and
functional
uniqueness
and
diversity
can
be
assumed
and
what
the
likely
consequences
for
species
survival
and
ecosystem
functioning
would
be.
Fur-
ther,
we
also
need
to
know
more
about
the
short-,
intermediate-,
and
long-term
importance
of
evolu-
tionary
potential
at
the
species,
community,
and
ecosystem
level.
We
suggest
building
on
research
evaluating
the
relevance
of
phylogenetic
diversity
for
ecosystem
functioning
[37,63–65]
and
the
link
be-
tween
past
evolution
and
recent
population
dynamics
[66].
Those
promising
research
fields
provide
already
some
insights
on
the
role
of
evolutionary
information
for
ecosystem
functioning
and
population
trends.
(ii)
We
also
call
for
a
comprehensive
guideline
through
the
jungle
of
available
phylogenetic
diversity
indices,
with
particular
respect
to
the
needs
of
conserva-
tionists
–
which
index
helps
to
protect
what?
(iii)
Instead
of
using
phylogenetic
diversity
as
a
new
silver
bullet,
scientists
should
always
communicate
clearly
on
the
advantages
and
disadvantages
of
the
metrics
and
the
reliability
and
feasibility
of
suggested
spatial
settings.
This
approach
is
necessary
to
increase
the
acceptance
of
scientific
results
and
recommendations
by
conservationists.
(iv)
The
importance
of
adding
any
evolutionary
aspect
to
protected-area
planning
should
be
assessed
quanti-
tatively.
For
spatial
planning
in
nature
conservation,
optimization
procedures
are
frequently
applied
[13]
and
it
should
be
an
easy
exercise
to
include
different
aspects
of
phylogenetic
diversity.
We
suggest
the
use
of
species-based
and
community-based
measures
of
phylogenetic
diversity
alongside
species
richness
in
such
optimization
tools
[67].
Also,
including
other
facets
of
diversity,
such
as
functional
diversity,
should
be
encouraged
whenever
possible.
This
would
result
in
maximization
of
the
set
of
species
to
be
conserved
and
in
the
identification
of
high
evolutionarily
and
functionally
distinct
communities
or
regions,
and
can
contribute
to
the
conservation
of
ecological
processes.
We
believe
that,
ultimately,
the
application
(not
only
the
recommendation)
of
such
an
approach
would
be
a
major
step
forward
for
modern
conservation
praxis
rather
than
using
abstract
ideas
on
the
potential
importance
of
phylogenetic
diversity
[29].
It
took
some
decades
before
already
accepted
scientific
knowledge
on
the
effects
of
climate
change
on
biodiversity
were
accepted
by
decision
makers
and
converted
into
relevant
policy
and
conservation
actions.
But
climate
change
has
obvious
effects
on
biodiversity,
whereas
the
potential
benefits
of
phylogenetic
diversity
for
nature
con-
servation
are
still
ambiguous.
Will
we
ever
see
a
national
park
designated
on
the
basis
of
phylogenetic
diversity?
Maybe,
but
only
if
phylogenetically
distinct
species
or
areas
with
high
phylogenetic
diversity
are
explicitly
con-
sidered
to
be
of
conservation
interest.
The
existence
of
the
already
mentioned
EDGE
programme
might
be
regarded
as
a
first
sign
in
this
direction.
One
will
learn
from
such
initiatives
whether
two
decades
of
agony
[1]
have
been
enough
for
a
concept
to
mature
and
be
applied
in
practice.
Acknowledgments
We
are
grateful
to
Ingolf
Ku¨
hn
for
comments
on
earlier
drafts
and
thank
Walter
Durka,
Stefan
Michalski,
and
the
team
at
the
EEF
symposium
‘Evolutionary
history,
ecosystem
function
and
conservation
biology:
new
perspectives’
[68]
for
fruitful
discussions.
We
also
acknowledge
the
helpful
and
detailed
comments
and
suggestions
from
three
anonymous
reviewers
and
Paul
Craze.
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Opinion Trends
in
Ecology
and
Evolution
April
2013,
Vol.
28,
No.
4
204

Nurturing
the
use
of
evolutionary
diversity
in
nature
conservation
Dan
F.
Rosauer
1
and
Arne
O.
Mooers
2
1
Division
of
Ecology,
Evolution,
and
Genetics,
Research
School
of
Biology,
Australian
National
University,
Canberra,
ACT
0200,
Australia
2
Department
of
Biological
Sciences,
Simon
Fraser
University,
8888
University
Drive,
Burnaby,
BC,
Canada
V5A
1S6
Winter
et
al.
[1]
have
started
an
important
conversation
about
why
evolutionary
diversity
(ED)
is
so
little
used
in
practical
nature
conservation.
We
focus
on
three
issues
from
their
commentary.
(i)
Does
ED
matter
for
conserva-
tion?
(ii)
If
so,
how
should
we
quantify
it?
(iii)
Depending
on
the
answers
to
the
first
two,
what
can
be
done
to
increase
ED
use?
Winter
et
al.
conclude
that
ED
is
too
weak
a
correlate
of
functional
diversity
or
evolutionary
potential,
and
that
its
best
use
is
as
a
surrogate
for
rarity
and
conservation
status.
This
correlational
argument
is
common
(we
have
made
it
ourselves)
but
it
is
also
false.
ED
need
not
be
a
surrogate
for
other
metrics
of
biodiversity
because
it
is
a
fundamental
measure
of
biodiversity.
It
is
certainly
a
better
measure
than
unranked
species
richness.
The
origi-
nal
line
of
argument
[2],
for
example,
that
echidnas
are
a
more
valuable
part
of
biodiversity
than
any
single
rodent
species,
retains
its
power.
We
are
dismayed
and
surprised
that
this
facet
of
ED
is
dismissed
with
no
analysis
at
all
by
Winter
et
al.
The
human
utility
of
biodiversity
is
of
course
central
to
its
conservation,
and
evidence
relating
ED
to
ecosystem
functions
such
as
productivity
[3]
and
stability
[4]
is
grow-
ing.
However,
by
rejecting
the
intrinsic
value
of
biodiver-
sity
as
a
rationale
for
conservation,
the
position
of
Winter
et
al.
would
also
make
much
species-level
conservation
hard
to
justify.
Should
we
only
protect
‘useful’
biodiversity
(e.g.,
through
a
Useful
Endangered
Species
Act)?
In
an
era
of
triage,
difficult
decisions
are
being
made,
and
we
know
that
inclusion
of
ED
could
make
a
substantial
difference
to
the
outcome
for
biodiversity
[5],
suggesting
that
it
should
be
considered
as
one
among
many
criteria.
If
so,
then
how
should
we
measure
it?
There
are
many
ED
metrics,
and
we
agree
with
Winter
et
al.
that
synthesis
and
guidelines
are
overdue.
However,
a
clear
basic
goal
of
conserving
ED
should
guide
our
path
through
the
jungle
of
metrics.
One
need
only
look
to
systematics
for
an
analogy:
because
the
goal
of
inferring
the
relationships
and
timing
of
common
ancestry
is
clear,
the
contentious
and
bewildering
sets
of
methods
for
phy-
logenetic
inference
do
not
override
the
utility
and
influence
of
the
final
product.
For
ED
conservation,
a
clear
and
unfettered
principle
is
possible:
the
diversity
of
life
can
be
understood
in
terms
of
evolutionary
lineages
rather
than
just
fixed
taxonomic
units,
and
we
can
quantify
this
diversity
(or
its
loss)
in
terms
of
the
branch
lengths
(generally
representing
time)
on
a
phylogeny
that
estimates
ancestral
relationships
[6].
The
goal
of
protecting
this
diversity
is
thus
advanced
not
by
identifying
assemblages
with
the
greatest
local
ED,
or
a
particular
community
phylogenetic
structure
(e.g.,
metrics
in
[7]),
or
even
in
targeting
rare
species
per
se
as
Winter
et
al.
suggest,
but
in
prioritizing
those
species,
areas,
or
actions
that
are
likely
to
best
enhance
the
persistence
of
the
diversity
of
the
Tree
of
Life.
Use
of
ED
in
practical
conservation
has
likely
been
limited
by
the
extended
laboratory
work
previously
need-
ed
to
generate
robust
phylogenies
of
appropriate
scale;
by
the
lack
of
easy-to-use
software;
and,
importantly,
by
too
few
clear
and
practical
guidelines.
We
can
be
opti-
mistic
with
regard
to
the
first
barrier,
because
the
time
and
cost
required
to
produce
a
phylogeny
are
rapidly
diminishing,
and
taxonomically
broad,
well-sampled
trees
are
becoming
increasingly
refined
[8–10].
Indeed,
commissioning
trees
specifically
to
inform
conservation
decisions
is
an
increasingly
viable
option.
Ready-to-use
software
is
also
becoming
available
[11,12],
although
more
could
be
done
to
make
mapping
of
ED
as
straight-
forward
as
mapping
of
species
diversity.
The
final
poten-
tial
barrier
is
thornier;
considering
evolutionary
relationships
in
conservation
decisions
will
make
a
real
difference
to
the
goal
of
preserving
the
Tree
of
Life,
but
clear
goals
and
clear
communication
are
essential.
We
hope
that
the
concerns
of
Winter
et
al.
act
as
a
necessary
tonic
in
this
regard.
Acknowledgment
We
are
grateful
to
Brent
Mishler
and
Carlos
Gonza
´lez-Orozco
for
valuable
comments
on
an
earlier
draft
of
this
letter.
References
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Corresponding
author:
Rosauer,
D.F.
(dan.rosauer@anu.edu.au).
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A.R.
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and
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al.
(2010)
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0169-5347/$
–
see
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matter
ß
2013
Elsevier
Ltd.
All
rights
reserved.
http://dx.doi.org/10.1016/j.tree.2013.01.014
Trends
in
Ecology
&
Evolution
xx
(2013)
1–2
Letter Trends
in
Ecology
&
Evolution
xxx
xxxx,
Vol.
xxx,
No.
x
TREE-1662;
No.
of
Pages
2
2

Conquering
current
obstacles
for
avoiding
the
misuse
of
evolutionary
diversity
in
nature
conservation:
a
reply
to
Rosauer
and
Mooers
Marten
Winter
1,2
,
Vincent
Devictor
3
,
and
Oliver
Schweiger
1
1
Department
of
Community
Ecology,
Helmholtz
Centre
for
Environmental
Research
GmbH
–
UFZ,
Theodor-Lieser
Str.
4,
06120
Halle
(Saale),
Germany
2
German
Centre
for
Integrative
Biodiversity
Research
(iDiv)
Halle-Jena-Leipzig,
Deutscher
Platz
5e,
04103
Leipzig,
Germany
3
Institut
des
Sciences
de
l’Evolution,
UMR
CNRS-UM2
5554,
Universite´
Montpellier
2,
Montpellier,
France
We
thank
Dan
Rosauer
and
Arne
Mooers
[1]
for
their
valuable
contribution
to
the
discussion
that
we
wanted
to
raise
with
our
recent
Opinion
in
TREE
about
the
rele-
vance
of
evolutionary
diversity
(ED)
in
present-day
con-
servation
plans
[2].
Conservation
biology
has
always
been
haunted
by
the
need
to
set
priorities
among
alternative
strategies
and
we
agree
with
Rosauer
and
Mooers
that
we
live,
more
than
ever,
in
times
of
triage
[3].
That
is
why
we
also
think
that
nature
conservation
needs
to
be
made
on
a
well-justified
basis.
With
our
article,
we
wanted
to
stress
that,
although
ED
is
certainly
not
a
priori
useless
for
conservation,
several
obstacles
still
need
to
be
overcome
before
it
becomes
an
effective
argument.
In
this
respect,
we
suggest
that
projecting
ED
as
a
surrogate
for
functional
diversity
or
evolutionary
potential
represents
often-used,
but
weakly
evidenced
arguments,
and
that
the
conserva-
tion
of
ED
should
not
be
based
on
such
arguments
unless
they
are
better
justified.
Rosauer
and
Mooers
further
argue
that
such
correla-
tional
justifications
are
even
neglecting
ED
as
a
fundamen-
tal
measure
of
biodiversity
on
its
own
[1].
The
echidna
example
of
Rosauer
and
Mooers
[1]
addresses
the
rarity
aspect
(we
used
the
example
of
Welwitschia
explicitly
in
that
sense),
which
leads
back
to
the
importance
of
consid-
ering
ED
as
a
value
per
se.
In
contrast
to
Rosauer
and
Mooers’s
interpretation,
we
did
not
want
to
dismiss
this
facet
of
biodiversity.
Besides,
living
in
times
of
triage
does
not
necessarily
mean
that
our
efforts
should
be
purely
anthropocentric
and
advantage
driven,
focusing
only
on
the
protection
of
‘useful’
biodiversity
[3].
In
fact,
we
believe
the
hazardous
argument
that
ED
is
a
surrogate
for
func-
tional
diversity
or
evolutionary
potential
can
even
be
used
to
promote
conservation
based
on
the
ability
to
maintain
current
or
future
ecosystem
services.
Instead
of
pleading
for
using
these
utilitarian
arguments,
we
hope
that
our
concerns
will
increase
discussion,
raise
awareness,
and
encourage
the
integration
of
ED
in
common
conservation
targets
based
on
stronger
and
less
utilitarian
justifications.
This,
however,
will
still
be
achieved
only
after
the
design
of
suitable
guidelines
and
well-defined
conservation
goals.
A
second
point
that
Rosauer
and
Mooers
[1]
raise
is
related
to
the
diversity
of
metrics.
Their
main
argument
is
to
prioritize
those
regions,
species,
and
so
on
that
ulti-
mately
‘enhance
the
persistence
of
the
diversity
of
the
Tree
of
Life’
[1].
However,
here
we
are
again:
do
we
really
know
what
to
protect
to
ensure
the
persistence
of
the
tree
of
life,
which
is,
as
far
as
we
understand
it,
something
different
from
conserving
the
highest
amount
of
ED?
In
other
words,
in
this
era
of
triage,
if
one
must
cut
or
protect
some
of
the
branches
of
the
tree
of
life,
which
ones
should
be
considered:
long
or
short
branches?
To
our
knowledge,
simply
calculat-
ing
ED,
whatever
the
metrics
used,
cannot
solve
this.
Pro-
tecting
the
tree
of
life
is
also
a
dilemma
because
it
is
an
additional
facet
of
biodiversity
that
we
call
to
be
conserved
on
top
of
already
existing
conservation
schemes.
Rather
than
using
ED
as
a
new
silver
bullet,
we
think
that
the
‘agony
of
choice’
in
conservation
is
a
matter
of
concern
needing
not
only
more
research
and
clear
communication
between
and
among
conservationists
and
stakeholders,
but
also
the
development
of
public
awareness
and
involvement.
We
are
grateful
to
Rosauer
and
Mooers
for
this
discus-
sion
and
hope
that
it
will
continue
to
motivate
similar
discussions
and
promote
research
projects
on
ED
in
ecology
and
conservation
science.
References
1
Rosauer,
D.F.
and
Mooers,
A.O.
(2013)
Nurturing
use
of
evolutionary
diversity
in
nature
conservation.
Trends
Ecol.
Evol.
http://dx.doi.org/
10.1016/j.tree.2013.01.014
2
Winter,
M.
et
al.
(2013)
Phylogenetic
diversity
and
nature
conservation:
where
are
we?
Trends
Ecol.
Evol.
28,
199–204
3
Bottrill,
M.C.
et
al.
(2008)
Is
conservation
triage
just
smart
decision
making?
Trends
Ecol.
Evol.
23,
649–654
0169-5347/$
–
see
front
matter
ß
2013
Elsevier
Ltd.
All
rights
reserved.
http://dx.doi.org/10.1016/j.tree.2013.02.011
Trends
in
Ecology
&
Evolution
xx
(2013)
1–1
Letter
Corresponding
author:
Winter,
M.
(marten.winter@ufz.de).
TREE-1679;
No.
of
Pages
1
1

Why
are
Red
List
species
not
on
the
EDGE?
A
response
to
Winter
et
al.
D.
James
Harris
and
Catarina
Rato
Centro
de
Investigac¸a
˜o
em
Biodiversidade
e
Recursos
Gene´
ticos
(CIBIO),
Universidade
do
Porto,
Campus
Agra´
rio
de
Vaira
˜o,
4485-661
Vaira
˜o,
Portugal
Winter
et
al.
[1],
Rosauer
and
Mooers
[2]
and
Winter
et
al.
[3]
discuss
the
importance
of
evolutionary
diversity,
and
highlight
its
limited
role
in
practical
nature
conservation.
We
suggest
that
the
International
Union
for
Conservation
of
Nature
(IUCN)
Red
List,
which
is
by
far
the
largest
and
most
comprehensive
assessment
of
conservation
status,
actually
acerbates
the
problem.
The
issue
of
‘taxonomic
inflation’
is
now
well
known,
where
genetic
diversity
measures,
often
linked
with
phylogenetic
species
concepts,
lead
to
a
greater
number
of
recognized
species
[4].
Such
species
splitting
‘could
be
detrimental
to
conservation’
if
threatened
species
are
incorrectly
split
[5].
A
likely
wider
problem
would
be
if
splitting
led
to
many
‘endangered
species’
showing
ex-
tremely
limited
genetic
distinction
from
other
related
species
within
which
they
had
previously
been
consid-
ered.
Indeed,
Sindaco
and
Jeremc
ˇenko
[6]
note
that
‘Many
conservation
biologists
prefer
to
raise
all
isolated
populations
to
specific
rank,
so
that
each
‘species’
receive
more
attention
(and
funds)
from
institutions’.
An
example
of
this
is
the
Critically
Endangered
terres-
trial
reptile
fauna
from
the
Mediterranean
region.
Of
the
13
on
the
IUCN
list,
there
are
no
genetic
data
for
three
of
them.
Of
the
remainder,
eight
out
of
ten
show
minimal
or
very
low
separation
from
their
sister
taxa,
less
than
half
of
the
level
of
divergence
typically
identified
between
reptile
species
when
estimated
using
the
cytochrome
b
gene
(av-
erage
13.6%
[7]).
A
ninth
species,
the
Be’er
Sheva
fringe-
fingered
lizard
Acanthodactylus
beershebensis
(Critically
Endangered)
is
a
distinct
lineage,
but
is
embedded
within
a
paraphyletic
lineage,
Acanthodactylus
pardalis,
a
species
of
Least
Concern
[8].
Thus,
the
giant
lizard
Gallotia
simo-
nyi,
which
is
endemic
to
the
El
Hierro
Island
in
the
Canary
Archipelago,
is
the
only
species
known
to
be
genetically
distinct
at
a
level
typical
of
other
species
out
of
the
13
on
the
Critically
Endangered
list
[9].
It
might
be
argued
that
this
is
an
exception,
but
it
appears
to
be
the
norm.
Bo
¨hm
et
al.
[10]
presented
the
first
ever
global
extinction
risk
for
reptiles,
based
on
a
random
representation
of
1500
species.
We
compared
all
the
available
species
that
were
categorized
as
Critically
Endangered
from
this
list,
and
for
which
cytochrome
b
sequences
(the
most
widely
sequenced
gene
across
reptiles)
were
available
(nine
in
total).
The
average
divergence
for
this
group
compared
with
their
sister
taxa
was
5.9%.
For
Endangered
species,
it
was
8.3%.
Clearly,
endangered
species,
particularly
Critically
Endangered
ones,
are
much
less
evolutionarily
distinct
on
average
than
those
of
lower
conservation
concern.
Another
global
conservation
initiative
is
the
one
proposed
by
Evolutionarily
Distinct
and
Globally
Endangered
(EDGE),
an
enterprise
that
highlights
and
protects
threatened
species
that
represent
a
unique
evo-
lutionary
history.
We
suggest
that
the
IUCN
needs
to
consider
incorporating
evolutionary
distinctiveness
into
their
assessments
in
such
a
fashion,
perhaps
by
adding
a
category
of
evolutionary
uniqueness
so
that
species
could
be
labeled,
for
instance,
as
CR
1
for
Critically
Endangered
and
highly
distinct,
which
would
have
higher
conservation
priority
than
CR
10
(Critically
Endangered
but
not
geneti-
cally
divergent).
Such
a
simple
but
practical
measure
could
bring
evolutionary
diversity
firmly
into
conservation
assessments.
Acknowledgments
D.J.H.
is
supported
by
a
‘Cie
ˆncia
2007’
contract
from
Fundac¸a
˜o
para
a
Cie
ˆncia
e
Tecnologia
(FCT),
Portugal.
References
1
Winter,
M.
et
al.
(2012)
Phylogenetic
diversity
and
nature
conservation:
where
are
we?
Trends
Ecol.
Evol.
http://dx.doi.org/10.1016/
j.tree.2012.10.015
2
Rosauer,
D.F.
and
Mooers,
A.O.
(2013)
Nurturing
the
use
of
evolutionary
diversity
in
nature
conservation.
Trends
Ecol.
Evol.
http://dx.doi.org/10.1016/j.tree.2013.01.014
3
Winter,
M.
et
al.
Conquering
current
obstacles
for
avoiding
the
misuse
of
evolutionary
diversity
in
nature
conservation:
a
reply
to
Rosauer
and
Mooers.
Trends
Ecol.
Evol.
http://dx.doi.org/10.1016/j.tree.2013.02.011
4
Isaac,
N.J.
et
al.
(2004)
Taxonomic
inflation:
its
influence
on
macroecology
and
conservation.
Trends
Ecol.
Evol.
19,
464–469
5
Zachos,
F.E.
(2013)
Taxonomy:
species
splitting
puts
conservation
at
risk.
Nature
494,
35
6
Harris,
D.J.
(2002)
Reassessment
of
comparative
genetic
distance
in
reptiles
from
the
mitochondrial
cytochrome
b
gene.
Herpetol.
J.
12,
85–
86
7
Sindaco,
R.
and
Jeremc
ˇenko,
V.K.
(2008)
The
Reptiles
of
the
Western
Palearctic,
Edizioni
Belvedere
8
Carretero,
M.A.
et
al.
(2011)
Adding
Acanthodactylus
beershebensis
to
the
mtDNA
phylogeny
of
the
Acanthodactylus
pardalis
group.
North-
West
J.
Zool.
7,
138–142
9
Cox,
S.C.
et
al.
(2010)
Divergence
times
and
colonization
of
the
Canary
Islands
by
Gallotia
lizards.
Mol.
Phylogenet.
Evol.
56,
747–757
10
Bo
¨hm,
M.
et
al.
(2013)
The
conservation
status
of
the
world’s
reptiles.
Biol.
Conserv.
157,
372–385
0169-5347/$
–
see
front
matter
ß
2013
Published
by
Elsevier
Ltd.
http://dx.doi.org/10.1016/j.tree.2013.03.006
Trends
in
Ecology
&
Evolution
xx
(2013)
1–1
Letter
Corresponding
author:
Harris,
D.J.
(james@cibio.up.pt).
TREE-1690;
No.
of
Pages
1
1