2. THE MEANINGS OF NATURE
TOPICS
▸ What is an invasive species?
▸ Restoration ecology
▸ Rewilding and de-extinction
▸ Geo-Engineering
▸ The politics of repair [biodiversity?]
3. THE MEANINGS OF NATURE
APOCALYPTIC VIEWS OF THE FUTURE
▸ The “doom hypothesis”:
▸ The environment is irretrievably damaged
▸ Warming (CO2 and methane)
▸ Pollution (e.g., heavy metals, plastics)
▸ Species extinction and collapse of critical ecosystems
▸ If so, what are our responsibilities?
▸ An ethical question rather than a technical question
4. THE MEANINGS OF NATURE
THE ISSUES FOR REPAIRING
THE WORLD
▸ First of all we have a “can” question:
▸ What can we do? How much will it cost us?
▸ Second we have a “precautionary” question:
▸ Is this likely to resolve things or make them worse?
▸ Thirdly we have a moral/ethical question:
▸ Should we do this thing? Do we have the right?
▸ The last question turns on the effects a repair might have for people as
well as the environment, and whether we can balance the rights of people
against the rights, if any, of the ecosystems and their parts
5. THE MEANINGS OF NATURE
THE LURE OF TECHNOLOGY
▸ One of the concerns is that having a technological solution (offered
by “technocrats”) is an easy cop-out, instead of
fi
xing the problem at
its source
▸ This is often raised against proposals to
▸ Deal with invasive species
▸ Resurrect extinct species that played a crucial role in an ecosystem
▸ Restore a degraded ecosystem arti
fi
cially
▸ Apply engineering solutions to deal with large-scale problems
(geo-engineering)
6. THE MEANINGS OF NATURE
WHAT KIND OF WILDNESS?
▸ Another topic is what we are seeking as the end-goal in such
measures
▸ 1950 levels or states?
▸ Pre-European ecosystems?
▸ Pre-human ecosystems (e.g., with megafauna)?
▸ Sustainability of ecosystems with large human populations?
▸ Post-human ecosystems?
▸ We have seen all these goals expressed in our survey of
environmentalisms
7. THE MEANINGS OF NATURE
WHAT IS A WEED?
▸ “A weed is a plant considered undesirable in a
particular situation, “a plant in the wrong place”
[Wikipedia]
▸ In short, a weed is something humans do not want there
(especially in agriculture)
▸ This is a subjective class of organisms that depends entirely
on the needs and goals of humans
▸ So, does this also apply to “invasive species”?
8. THE MEANINGS OF NATURE
INVASIVE SPECIES IN AUSTRALIA
And that’s
just large
animals:
Fish, plants
insects, and
molluscs
also!
9. THE MEANINGS OF NATURE
CLASSIFICATION OF “ALIEN” SPECIES
Classification Definition
Native Species present by natural means
Formerly native
Species no longer present but which occurred naturally in the past.
Subdivisions: (1) those which could survive if reintroduced; (2) those which
could no longer survive in today’s environment and climate
Locally non-native Species introduced by humans beyond their natural geographical range
Long-established (or ‘naturalized’)
Species introduced by humans long ago which are now part of the food
webs of native species
Recently arrived
Species colonizing as a result of human activities (eg, land-use practices;
human-induced climate change)
Alien Species introduced by humans, either deliberately or accidentally
Table 1 from Warren 2007
10. THE MEANINGS OF NATURE
THE CASE OF THE DINGO
▸ Which of these categories covers Australia’s “native” dog?
▸ Introduced to continent between 4,640–18,100 years ago (not found
in Tasmania) from East Asian domestic dogs and New Guinea Singing
Dog
▸ Probably contributed to the extinction of the thylacine and Tasmanian
devil on mainland [Ardalan et al. 2012]
▸ Not native nor formerly native, as introduced by humans
▸ Not locally non-native as this is not an extension of their “natural” range
▸ So, naturalised, recently arrived or alien? A case can be made out for
each: depends on de
fi
nitions of “long ago” and “part of food webs”
11. THE MEANINGS OF NATURE
TO MAKE IT MORE COMPLEX
Colautti and
MacIsaac 2004
12. THE MEANINGS OF NATURE
RESTORATION ECOLOGY
▸ This leads us nicely to the topic of restoration ecology:
▸ To what are we restoring the ecosystem?
▸ Would that include the dingo or not?
13. THE MEANINGS OF NATURE
RESTORATION ECOLOGY
“Here is the means to end the great extinction spasm. The next century will, I
believe, be the era of restoration in ecology.”
E. O. Wilson 1992, 324
“Ecological restoration is a form of domination, another instance of
humanity’s attempt to control the natural world. We restore natural
environments to correct our mistakes, to make ourselves feel better about the
massive destruction of the natural world that we have caused. But this policy
is, at best, a self-deception. As Scherer notes, successful restoration projects
may convince us that all ecological damage is repairable; thus, we may
continue to exploit and degrade the biosphere ….
Ecological restoration is an expression of a misguided faith in human
omnipotence, the human power to control and shape the natural world. It
would be much better if we were to attempt to control ourselves. What needs
to be restored is not degraded ecological systems but the human capacity for
understanding the limits and meaning of our power over the natural world.”
Eric Katz 1996
14. THE MEANINGS OF NATURE
TECHNOCRACY AND RESTORATION
▸ Katz’s criticism of the easy optimism of Wilson is sharp
▸ However, without Wilson’s optimism, we are just dead in the
water
▸ Which way should we go?
▸ Why not both?
▸ Realistic optimism
▸ Incidentally, Wilson’s book, reissued in 2001 is
still one of the best overall introductions to the
problems and nature of biodiversity. It is well
worth a read.
15. THE MEANINGS OF NATURE
REWILDING NATURE
▸ Rewilding is de
fi
ned as
“the reorganisation of biota and ecosystem processes to set an identi
fi
ed
social–ecological system on a preferred trajectory, leading to the self-
sustaining provision of ecosystem services with minimal ongoing
management”
Petorelli et al. 2017
“Reintroduction of extirpated species or functional types of high ecological
importance to restore self-managing functional, biodiverse ecosystems”
Naundrup and Svenning 2015
“[Rewilding] is based on trophic cascade and island biogeography models
that dictate that large predators (Carnivores) regulate the food chain, that
they need large central reserves of land (Cores) for hunting and for
territory, and that these reserves need to be connected so that populations
can move and interchange (Corridors)“
Gammon 2018, citing Soulé and Noss 1998
16. THE MEANINGS OF NATURE
PROPOSED REWILDING
▸ In Eurasia and the Americas, rewilding proposals have
included:
1. Introducing elephants to North America to make up for the
loss of mammoths
2. Reintroduction of wild species like wolves, caribou, lynx,
beavers
▸ In Australia: camels and buffalo have already made a
difference.
▸ Some have proposed lions, tigers, Komodo dragons
17. THE MEANINGS OF NATURE
DE-EXTINCTION
▸ Many of the megafauna (large bodied
animals) are now extinct, such as Asian lions,
mammoths, Diprotodon (large wombat),
thylacine, thylacoleo, etc.
▸ Recent extinctions have DNA resources,
and many have proposed reviving these
species for rewilding
▸ Are they the same species?
▸ Will they play the same role in disturbed
ecosystems?
18. THE MEANINGS OF NATURE
IS DE-EXTINCTION RESTORATIVE?
▸ If we use, Jurassic World-style, wombat and
fossil Diprotodon DNA to revive the latter, is
it really Diprotodon, and will it play the same
role ecologically?
▸ Species concepts: continuity – is it important?
▸ Are niches/ecological roles stable enough to
fi
t these revived species into them?
▸ What about existing niche occupants?
19. THE MEANINGS OF NATURE
IS REPAIRING NATURE OUR JOB?
▸ Some people will claim that this is part of evolution, and nature will repair
itself
▸ This is quite true, from a geological perspective
▸ But from a human perspective:
“Consider the … possibility raised with regularity: why not just
forget the problem and let natural selection replace the species
that are disappearing? It can be done if our descendants are
willing to wait several million years. Following the
fi
ve great
extinction episodes of geological history, full recovery of
biodiversity required between 10 and 100 million years.”
Wilson 1992, 316
▸ We made the mess; can we clean it up? is the question, not should we?
20. THE MEANINGS OF NATURE
GEO-ENGINEERING
▸ I will cover this in more detail in the
fi
nal lecture
▸ For now, we must consider the implications of changing the globe “back to”
some state (i.e., cooler)
▸ Unforeseen consequences (e.g., seeding the atmosphere and the chemical
“fallout”)
▸ We have still sequestered 90% of the planet for our production – little will
fi
nd
its way back to a “pristine” ecotype
▸ We have to change ourselves: smaller populations and less greenhouse gases
and pollution
▸ But our locally competitive economic systems make that almost impossible
to achieve
▸ What politics should we adopt then?
21. THE MEANINGS OF NATURE
OVER TO YOU
▸ I am of the Baby Boomer generation (1945–1965); I will not
see the results of conspicuous consumption and growth
economics [I did see many of the bene
fi
ts though]
▸ Those in power are of GenX (1965–1985); this cohort has to
deal with the problems of now
▸ You are millennials; you have to deal with this issue in the
near future. How should you do this?
▸ What about the next generation after you?
22. THE MEANINGS OF NATURE
REFERENCES
Ardalan, Arman, Mattias Oskarsson, Christian
Natanaelsson, Alan N. Wilton, Afshin Ahmadian,and
Peter Savolainen. “Narrow genetic basis for the
Australian dingo confirmed through analysis of
paternal ancestry.” Genetica 140, no. 1 (2012): 65–
73. https://doi.org/10/f23mh4.
Colautti, Robert I., and Hugh J. MacIsaac. “Aneutral
terminology to define ‘invasive’ species.” Diversity
and Distributions 10, no. 2 (2004): 135–41. https://
doi.org/10/crshsp.
Gammon, Andrea R. 2018. “The many meanings of
rewilding: an introduction and the case for a broad
conceptualisation.” Environmental Values 27 (4):
331–50. https://doi.org/10/gd538q.
Eric Katz. “The problem of ecological restoration.”
Environmental Ethics 18, no. 2 (1996): 222–24.
https://doi.org/10.5840/enviroethics199618236.
Naundrup, Pernille Johansen, and Jens-Christian
Svenning. “Ageographic assessment of the global
scope for rewilding with wild-living horses (Equus
ferus).” PLOS ONE 10, no. 7 (July 15, 2015):
e0132359. https://doi.org/10/f7xvbt.
Pettorelli, Nathalie, Jos Barlow, Philip A. Stephens,Sarah
M. Durant, Ben Connor, Henrike Schulte to Bühne,
Christopher J. Sandom, Jonathan Wentworth,and
Johan T.Toit. “Making rewilding fit for policy.”
Journal of Applied Ecology 55, no. 3 (January 22,
2018): 1114–25. https://doi.org/10/gdfvz4.
Warren, Charles R. “Perspectives on the ‘alien’ versus
‘native’ species debate: a critique of concepts,
language and practice.” Progress in Human
Geography 31, no. 4 (2007): 427–46. https://
doi.org/10/ch2gmh.
Wilson, Edward O. The diversity of life. Cambridge, MA:
Belknap Press of Harvard University Press, 1992.