sciencemag.org SCIENCE 400 25 JULY 2014 • VOL 345 ISSUE 6195
The rate at which animals are vanishing from this planet is one of the signatures of this age, as ure a sign of human dominance as our impact on Earth’s nitrogen, phosphorus, and carbon cycles. This disappearance of animals from the world’s ecosystems is generally a by-product of human activity, not an intentional act. Animals
do matter to people, but on balance, they matter less
than food, jobs, energy, money, and development. As
long as we continue to view animals in ecosystems as
irrelevant to these basic demands, animals will lose.
If we accept that humans
now shape the future of this
planet, the future for existing and extirpated fauna
will depend on vision as
much as on science. What
type of world do we want
to pass on, and what role do
animals have in that world?
A responsible vision
must include the dominating influence of people on
the planet. The near future
is likely to include 8 to 9 billion people, 3 billion more
people in the middle class,
a doubling of the terrestrial footprint of cities, and
a transformation of global
food and energy systems.
A vision that includes a
vital future for animals
requires thinking beyond
“restoration” and even beyond “rewilding.” To maintain the animal diversity
of the present and restore
the animal abundance of
the past, we must place
animals squarely in a world where human systems are
integrated with functioning natural systems. We cannot focus on recreating the ecosystems of the past—our
impacts are making this untenable in most places—but
we must not give up on nature or wildness, either.
To begin, we need to recognize the importance of
animals in all socioecological systems, pristine and
human-dominated, terrestrial and marine. When we
consider the benefits of a world rich with animals, we
should shift some of our focus to systems where many
people depend on animals. As an example, 2.6 billion
people depend on ocean animals for protein.
In addition, we will have to grapple with tricky is-
sues, such as those associated with the management
of novel ecosystems and species substitution. There
is also the potential application of synthetic biology,
but the positive and negative impacts must be fully ex-
plored. How do we reduce the risks of ecosystem-level
experimentation? When considering whether to intro-
duce a new species into a system to replace the loss of
another, for example, we must weigh the consequences
of no intervention against the consequences of actions
taken to recover ecological
function. This is not a triv-
ial exercise, as the ecologi-
cal, economic, and cultural
impact of an animal within
an ecosystem is dynamic,
and often obscured by com-
plex ecological dynamics,
shifting baselines (what a
natural system “should” be
like), and changing cultural
norms. A full understand-
ing of the relevant natural
history, as well as the values
of the people with a stake
in the outcome, will be es-
sential to any path forward.
This is not entirely new ter-
ritory, as our successes and
failures in biological con-
trol can serve as a guide.
We cannot give up on the
difficult species—the species
that do not coexist well with
people and require large
areas for their survival.
Conservation of these
animals will hinge on
recognition of their full
value—ecological, economic, and cultural—by those with
the power to protect them. A country with many large
animals has as much right to development as a country
without, and thus the global community must find path-
ways that would allow communities sharing their land
with these animals to benefit from their presence.
Defaunation is a global issue. A world without animals represents a loss to humanity as much as a loss
to ecology.
An animal-rich future
Joshua J.
Tewksbury is
director of the Luc
Hofmann Institute
at the World Wide
Fund for Nature,
Gland, Switzerland.
E-mail:
jewksbury@
wwfint.org
– Joshua J. Tewksbury and Haldre S. Rogers
10.1126/science.1258601
“A vision that includes a vital
future for animals requires
thinking beyond ‘restoration’
and even beyond ‘rewilding.’”
SPECIAL SECTION VANISHING FAUNA
Haldre S. Rogers
is a faculty fellow
in the Department
of BioSciences,
Rice University,
Houston, TX, USA.
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