Geoscience Reference
In-Depth Information
biophysical world (i.e. an alteration to 'intrinsic nature') and its govern-
ing logics (i.e. a disruption of 'super-ordinate nature'). The latter two
forms of metonymy are scarcely new. The science of ecology makes
this plain. For decades, ecologists believed that the 'natural' state of
most ecosystems was to be stable and ordered. For instance, the early
twentieth-century researchers Frederic Clements and Arthur Tansley
suggested that plant communities, given time, adapt to the prevail-
ing climatic, pedological and other environmental conditions found
in any given locality or region. These conditions were presumed to be
consistent over a period of hundreds if not thousands of years, result-
ing in a 'climax ecology'. Similarly, biologists studying wild animals
long believed that predators and their prey existed in a homeostatic
relationship: the numbers of both, it was suggested, tended to hover
around a mean because an 'excess' of one would necessarily be elimi-
nated by a 'scarcity' of the other. After 1950, these ideas slowly fell out
of favour and a new paradigm emerged, namely 'non-equilibrium ecol-
ogy'. It was showcased in an influential book by American biologist
Daniel Botkin, counter-intuitively titled
Discordant harmonies
(Botkin,
1990; see more recently, Kricher, 2009). This 'new ecology' suggests
that ecosystems and species (contrary to older beliefs) are profoundly
shaped by disturbances, routinely cross operational thresholds and nor-
mally exhibit variable behaviour in time and space. Despite this, it has
two key similarities with its predecessor. First, it presumes that 'nature'
possesses a signature quality waiting to be discovered - in this case, its
'disorderliness'. Second, it is also assumed that any particular ecosys-
tem or species can tell us something about this general characteristic of
life on Earth.
For instance, here is the 'new' ecologist Stephen Budiansky writing
about the giant beech trees of southern Chile a few years after Botkin's
book was published:
The first botanists who entered these remote and towering woods
believed they had discovered a classic example of a forest climax com-
munity
to admit it, but there was
something terribly wrong with this explanation. Nothofagus seeds
are virtually absent from the forest floor. Other trees are present
in all sizes and ages; the false beeches appear only in the narrow
age-band of oldest trees that form the canopy. What keeps these
other species from ousting the false beeches
...
It took a long time for [them]
...
...
...
[I]t is noth-
ing short of repeated disaster that is responsible for the illusion of
stability
?
Nothofagus are adapted not to stability but chaos. The
mountains are regularly shaken by powerful earthquakes
...
...
when the
hillsides are laid bare by these upheavals, Nothofagus seedlings grow
in abundance. By the time that shade tolerant competitor species
have invaded
...
the false beeches have gained a substantial head
