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De-extinction,
Authenticity
and Wildlife
Conservation
Doug Campbell
Department of Philosophy
What is
de-extinction?
• It is the
procedure of
recovering
extinct genes
and pasting
them into
living
organisms.
Conservation applications of de-extinction:
#1. Restoring genetic health to
genetically depauperate species by the
recovery and intra-species transfer of
extinct genes.
Black Footed Ferret
Kakapo
Conservation applications of de-extinction:
#2. Genetic fortification and facilitated
evolution of species by inter-species
gene transfer (where the donor
species might be extinct)
American Chestnut (which has been made resistant
to Chestnut blight by adding an anti-fungal enzyme
from wheat.)
Asian elephant, which might be enabled to
range up towards the Arctic circle if given
few mammoth genes
Conservation applications of de-extinction:
#3. Restoration of lost ecosystems via
the engineering, through inter-species
gene transfer, of living proxies for
extinct keystone species.
Conservation applications of de-extinction:
#4. The resurrection of extinct species
(i.e., of entire genomes)
Passenger Pigeon
Pyrenean Ibex
Gastric brooding frog
Moa
Tasmanian tiger
Huia
Conservation applications of de-extinction:
#5. The triaging of endangered species
and reversible managed extinction of
selected species.
Where should we draw the line? Some
positions:
De-extinction has no legitimate place in conservation at all
Increasingly extreme
De-extinction of genes is OK
The re-engineering of existing species is OK
The re-engineering of environments is OK
The de-extinction of species is OK
No holds barred de-extinction
1. Recovering lost
genetic diversity
2. Facilitated
adaptation
3. Proxies for
keystone species
4. Species deextinction
5. Managed
extinction
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“How to Clone a Mammoth”
by Beth Shapiro (2015)
• Shapiro is a paleogeneticist
at University of California,
Santa Cruz.
• She defends an
intermediate position
Shapiro’s position:
Increasingly extreme
The re-engineering of environments is OK
Species de-extinction isn’t.
1. Recovering lost
genetic diversity
2. Facilitated
adaptation
3. Proxies for
keystone species
4. Species deextinction
5. Managed
extinction
✓
✓
✓
✗
✗
My aim: to put pressure on Shapiro’s position, and
argue in favor of the conservation-value of species deextinction
The de-extinction of species is OK
No holds barred de-extinction
?
Increasingly extreme
The re-engineering of environments is OK
Species de-extinction isn’t.
1. Recovering lost
genetic diversity
2. Facilitated
adaptation
3. Proxies for
keystone species
4. Species de✓
extinction
5. Managed
?
extinction
✓
✓
✓
✗
✗
Major Caveats
1. I don’t think we should devote any of our inadequate
conservation resources to de-extinction now.
–
We should just be freezing samples in preparation.
2. I agree that if the idea of species de-extinction were to
begin to occupy the thoughts and attention of
conservationists, then this would be bad.
–
It would be a distraction from other far more pressing issues
(like present government polices).
3. I don’t think that the techniques of synthetic biology
provide any sort of general hi-tech panacea for species
extinctions of the past or the future.
–
De-extinction is only technically plausible for a small subset of
extinct species, and even then it will almost always be much
more difficult and expensive than preventing a species from
going extinct in the first place.
Another caveat
• If I am right, then there are good reasons to
reverse certain historical extinctions. But it
remains possible that, although these good
reasons exist, they are offset by even stronger
reasons not to reverse historical distinctions.
1. Moral hazard. (It will no longer be the case that
“extinction is forever”, which will let rapacious
developers and industrialists off the hook.)
2. It is a thin edge of a GMO wedge.
3. It might destabilize existing ecosystems.
4. Etc…
• Which reasons are strongest—those for making
species de-extinct, or those against?
• I set this (big!) question aside.
Extinct species are gone forever. We will
never bring something back that is 100
percent identical—physiologically, genetically,
and behaviorally identical—to a species that
is no longer alive. (p. 10)
It is not important that we cannot bring back
a creature that is 100 percent mammoth or
100 percent passanger pigeon. What matters
is that—today—we can tweak an elephant
cell so that it expresses a mammoth gene. (p.
207)
The product of de-extinction won’t be
the same thing as the original species…
Crucially however, I don’t care that it’s
not the same thing as the original... The
task ahead is not to make perfect
replicas of species that were once alive.
First, it is technically not possible to do
so and is unlikley ever to be technically
possible to do so. Second, there is no
compelling reason to make perfect
replicas of extinct species. The goal of
de-extinction is to restore or revive
ecosystems.… We don’t need to create
exact replicas of extinct species to
achieve this goal. Instead, we can
engineer species that are alive today so
that they can act as proxies for extinct
species. (p. 205)
Shapiro’ claims
A mammoth will not have to be pure in order
to be received as a mammoth. This is a relief,
because … while 100 percent mammoth is
out of the question, 1 percent mammoth
may not be. (p. 130)
In my mind, it is ecological resurrection, and not species resurrection, that is the real value
of de-extinction. We should think of de-extinction not in terms of which life form we will
bring back, but what ecological interactions we would like to see restored. (p. 131)
Shapiro’s claims, in my words
S1: It is not technically possible, and
almost certainly will never become
technically possible, to create
organisms that are perfect replicas of
extinct organisms.
S2. In order to resurrect an extinct species,
it would be necessary to create
organisms that are prefect replicas of
extinct organisms.
S3. Even if it were possible to resurrect an
extinct species (which it isn’t, because
of S1 and S2), there would be no
compelling conservation-based reason
to do so.
She is the paleogeneticist,
and I am the philosopher:
so I defer to her on S1
I will argue for the
following claim, which
contradicts S1 and S2:
C. There are compelling
conservation-based
reasons to resurrect some
species, and these
reasons apply even if the
resurrected organisms are
not perfect replicas of the
originals.
Plan
• First I give two brief arguments that suggest C
must be true:
C. There are compelling conservation-based reasons to
resurrect some species, and these reasons apply even if
the resurrected organisms are not perfect replicas of the
originals.
• Then I attempt to identify the ‘compelling
conservation based reasons’ that C mentions.
First Argument for C:
The clone/extinction thought-experiment
Scenario 1
• Stage 1. Goats are produced
via cloning, using sheep as
the surrogate parents.
• Stage 2. All goats except the
cloned goats die out.
• Stage 3. The only goats now
to be found are goats that
are the products of cloning.
• Are goats now extinct?
Surely not. The species lives
on, albeit that there maybe
telltale signs in the species’
genes that it was cloned.
Scenario 2
• Stage 1. Goats go extinct.
• Stage 2. New goats are produced
via cloning, using sheep as the
surrogate parents and stored
goat cell samples.
• Stage 3. The only goats now to
be found are goats that are the
products of cloning.
• Are goats now extinct? Surely
not. This situation differs from
scenario 1 only in regards the
order in which Stage 1 and Stage
2 occur, and this appears to be
irrelevant to whether the species
is now extinct.
Scenario 1
Scenario 2
Why does the clone/extinction
thought experiment suggest that C is
true?
C. There are compelling conservation-based reasons to resurrect
some species, and these reasons apply even if the resurrected
organisms are not perfect replicas of the originals.
• Answer:
– Were we to save goats (or any other species) from extinction in the
manner of scenario 1, this would be a major conservation victory.
– By the same token, it should be a major conservation victory were we to
render goats de-extinct in the manner of scenario 2.
» There is apparently no difference between the two scenarios that
should make a difference to the conservation value of the outcome.
– This is true regardless of whether the cloning process introduces slight
changes into the genetics of the goats.
Second Argument for C:
The facilitated adaptation argument
Threatened
Asian Elephant
“Facilitated
adaptation”
Asian elephant
that is no longer
threated
A great conservation success!!
(According to Shapiro)
But Threatened
if facilitated
Pyrenean
evolution
can be a
Ibex
conservation
success story,
Extinction then so too, by
the same
Cloningreasoning, can
de-extinction
(even if the deextinct organisms
Slightly
aren’t
exactly the
modified
same
as their
“de-extinct”
forebears).
Pyrenean Ibex
Of no conservation value.
(According to Shapiro)
The question the rest of the talk will
focus on:
C. There are compelling conservation-based reasons to
resurrect some species, and these reasons apply even if
the resurrected organisms are not perfect replicas of the
originals.
What are these reasons?
Case study:
the huia
The huia appears to be a good candidate for deextinction for several technical reasons
1. Genetic material. There are thousands of museum
specimens.
2. Habitat. There are multiple predator free mainland
islands and offshore islands to which they could be
translocated.
3. Animal husbandry. Huia were easily kept in captivity.
4. Containment. Huia were not capable of sustained flight.
5. Founder group size. They formed life-long pairs, which
means only a relatively small founder group is needed.
6. Smallish genome.
7. Technique. The primordial germ cell transfer method can
be used instead of cloning with birds. It is much more
efficient.
A drawer full of huia at Auckland
museum:
What compelling reasons are there to
make the huia de-extinct?
1. We owe it as a debt of restorative justice to the huia
themselves.
– But we can’t owe a debt of restorative justice to a species,
since species are not intentional agents (Sandler 2013)
– Nor we can we owe such a debt to individual huia, since
there presently are none.
2. We should do it to mitigate human guilt.
– But a child isn’t guilty for the crimes of her parents.
3. We should do it to turn back the clock and right our
ancestors’ wrongs.
– But it is not clear that there is in general anything morally
‘wrong’ in one species causing the extinction of another.
4. We should do it to recover things of value that were
lost when the huia went extinct.
Possible sources of value that justify
the conservation of species
Seldom obtains, and
• Anthropocentric values
when it does it is
philosophically
uninteresting
– Commodity/economic value (directly money
related)
– Amenity value (improves human lives in a way Controversial
that is not directly money related.)
– Moral value (e.g., as an aid to our being better Hard to argue for in
the case of a species
people.)
that is already extinct
– Option value: the value we should place on a
species based on our ignorance of ways in
which it might turn out to be directly valuable.
• Intrinsic values
– The intrinsic value of individual plants/animals
Controversial
– The intrinsic value of ecosystems
Controversial
Bryan Norton (2003, p. 470) on why
arguments from amenity value are most
effective
“To those who are uncommitted to
environmentalism … appeals to intrinsic values in
nature and to the rights of nonhumans appear
‘soft’, ‘subjective’, and ‘speculative’. We can accept
this fact of political life without agreeing with it.
Whatever the answer to the intellectual question of
whether nonhuman species have intrinsic value, ...
human oriented reasons carry more weight in
current policy debates”
Why was the huia of amenity value?
1. It was of enormous aesthetic value to human
beings enjoying the NZ bush.
2. It was of enormous cultural value to the
Māori.
The cultural value of the huia
• It was the most tapu of all creatures for the Māori.
• Its extinction was a devastating cultural loss for the
Ngati Huia.
The aesthetic amenity value of the
huia
• It was a very charismatic
animal.
– Extreme sexual dimorphism
(most extreme of any bird
in the world)
– Beautiful appearance.
– Very attractive song.
– Very confiding.
– Monogamous breeding
pairs that fed cooperatively.
The huia is a close relative of the
kokako
The huia’s demise
• The tale of its demise was especially
tragic.
• Buller:
– “While we were looking at and
admiring this little picture of bird-life,
a pair of Huia, without uttering a
sound, appeared in a tree overhead,
and as they were caressing each other
with their beautiful bills, a charge of
No. 6 brought them both to the
ground together. The incident was
rather touching and I felt almost glad
that the shot was not mine, although
by no means loth to appropriate 2 fine
specimens.”
Buller
The huia’s demise
• The 1902 visit of the
Duke of York to
Rotorua
• A plausible claim:
– the extinction of the huia was an act of barbaric
environmental vandalism, that—quite apart from the
fatal harm it did to the huia themselves—also causes
ongoing harm to us and to our decedents.
– How has the extinction of the huia harmed us?
• By making the New Zealand bush a lot less wonderful than it
used to be.
• By making our actual experiences less rich and (for those of
us who wouldn’t have gone into the bush to see them
anyway) by imposing restrictions on what we could choose
to experience.
• By making the world less diverse, varied and interesting (this
goes for extinction generally).
• Similarly, we would be harmed were someone to set about
making, say, the tui, or the bellbird, or the kokako extinct.
An analogy with the destruction of
natural, historical and cultural
landmarks and artifacts
• I will now focus in particular on the aesthetic
amenity value of the huia.
• My claim will be that there is at least one
compelling conservation-based reason to
resurrect the huia: namely, to recover the
aesthetic amenity value that was lost when it
went extinct.
Is it possible to recover the huia’s
aesthetic amenity value?
A Picasso
Lots of
aesthetic value
It is destroyed
A replica is made
Not much
aesthetic value
Ancestral
huia
Lots of
aesthetic value
Raven
Information
about
superficial
appearance
Not much
aesthetic
value
Superficial huia
DNA
Eggs
Lots of
aesthetic
value
Huia from old eggs
??
The relationship R
• Let us say that the ancestral huia and the new
birds stand in relation R to each other iff the
aesthetic value possessed by the ancestral
huia is also possessed by the new birds.
Ancestral
huia
Lots of
aesthetic value
Raven
Information
about
superficial
appearance
not R
Not much
aesthetic
value
Superficial huia
DNA
R
?
Eggs
Lots of
aesthetic
value
Huia from old eggs
??
What is relation R?
• A pretty obvious, biologically unsophisticated
hypothesis:
– Relation R obtains iff both:
1. The new birds are descended from the ancestral huia;
and
2. The new birds share (essentially) the same form,
physiology and behaviour as the ancestral huia.
• Note that neither condition 1 nor 2 appears
to be sufficient by itself.
A more biologically sophisticated
hypothesis:
• Relation R obtains iff both:
1.
2.
The genes of the new birds have been inherited in a
counterfactual supporting way from the ancestral huia; and
The genes of the new birds are being phenotypically expressed
as they were in the ancestral huia.
• This implies that Relation R can obtain to different
degrees depending on how many genes have been
inherited and are being expressed correctly.
• It also submits to an adaptivist reading:
– Relation R obtains to the degree that the traits of the new
birds are explained by natural selection operating on the
population of ancestral birds.
Junk DNA and hybrids
• Junk DNA case: the new birds have kokako junk DNA, but
all their phenotypically expressed genes are copied from
the ancestral huia.
• Hybrid case: the new birds have kokako junk DNA, and also
have some kokako genes. But most of their genes are huia
genes, and the kokako genes do not interfere with the
phenotypic expression of the huia genes or vice versa (i.e.,
the two sets of genes ‘play well’ with each other.)
• In both these cases relation R will obtain to a degree, and
as a result some but not all of the aesthetic value of the
ancestral huia will have been be recovered by creating the
new birds.
• Presumably a law of diminishing returns will operate.
Conclusion
• Shapiro’s claims:
– S1: It is not technically possible, and almost certainly will never become
technically possible, to create organisms that are perfect replicas of extinct
organisms.
– S2. In order to resurrect an extinct species, it would be necessary to create
organisms that are prefect replicas of extinct organisms.
– S3. Even if it were possible to resurrect an extinct species (which it isn’t,
because of S1 and S2), there would be no compelling conservation-based
reason to do so.
• My claim (which contradicts S1 and S2):
– C: There are compelling conservation-based reasons to resurrect some
species, and these reasons apply even if the resurrected organisms are not
perfect replicas of the originals.
• Evidence:
– The cloning/extinction thought experiment.
– The facilitated adaptaton argument.
• What are the compelling conservation based reasons in question?
– The recovery of lost aesthetic amenity values (among others).
– These can be recovered provided my hypothesis about relation R is correct.
– The burden is on the opponent to show why this hypothesis is inadequate.