SYSTEMS ECOLOGY IN THE JET STREAM OF SCIENTIFIC
DEVELOPMENT
Seven general scientific theories have changed our per ception of nature radically during
the last 100 years: general and special relativity, quantum theory, quantum
complementarity, Go ¨del’s theorem, chaos theory, and theory for far from
thermodynamic equilibrium systems. With these seven theories, we understand today
that nature is much more complex than we thought 100 years ago, but we also have tools
to understand this com plexity better, which has entailed that we have a general
ecosystem theory today. The speed of light is the absolute upper limit for any transmission
of matter, energy, and information according to the special relativity theory. This has
given a comple tely new meaning to the concept of locality. It has also in systems ecology
brought another meaning of network: links among components that share a locality and
of the hierarchical organization: networks of smaller and smaller localities that are linked
together on the next level of the hierarchy. Relativity theory also gives us a clear under
standing of the lack of absolute measures, which was the governing scientific perception
before the twentieth cen tury.
When we use ecological indicators to assess ecosystem health, we can only apply them
relatively to other (similar) ecosystems; and, when we use thermo dynamic calculations
of ecosystems we know that we cannot get the absolute value but only an index or relative
value because ecosystems are too complex to allow us to include all the components in
our calculations. Quantum theory and later chaos theory upended the deterministic world
picture: we cannot determine the future in all detail, even if we know all details of the
present condi tions. The world is ontically open. In the nuclear world, uncertainty is due
to our inevitable impact on nuclear particles, while in ecology the uncertainty is due to
the enormous complexity.
Ecosystems are middle number systems. The number of components in such systems is
many orders of magnitude smaller than the number of atoms in a room but too many to
be countable. Further complicating the situation is that while the atoms are represented
by a few different types all ecosystem com ponents are different even among organisms
of the same species. A room may contain 10 28 components but they are represented by
only 10 or 20 different types of mole cules with exactly the same properties. An ecosystem
contains in the order of 10 15 –10 20 different components.
Such complexity leads to a nondeterministic picture in ecology. In accordance with
quantum complementarity, light can only be described by an interpretation as both waves
and particles (photons). An ecosystem is much more complex than light. Therefore, a full
(holistic) description of an ecosystem will also, not surprisingly, require two or more
complementary descriptions. Various descriptions suggest ecosystems as dissipative, self
organizing systems that follow a dynamic to increase energy, emergy, ascendency (see
Ecological Network Analysis, Ascendency), or eco exergy which are not in conflict, because
they cover different aspects of the eco system. All descriptions help to understand
ecosystem dynamics, but some may be more applicable for addres sing specific ecosystem
questions. Go ¨del’s theorem that there are no complete theories – they are all based on
some assumptions – is of course also valid for ecological theories. We shall not expect a
com plete theory based on no assumptions and which can be used in all contexts.
Newtonian Physics is based on the reversibility of all processes. Prigogine’s new
interpretation of the second law of thermodynamics has shown that time has an arrow.
All processes are irreversible and evolution is rooted in this irreversibility. Einstein’s
special relativity theory, which provides the speed of light as an upper speed making it
impossible to change the light signals which give information about a previous event, also
supports the principle of irreversibility.
We cannot change the past but only the future. With the enormous complexity of
ecosystems it also implies that the same conditions will never be repeated . Ecosystems
are always confronted in space and time with new chal lenges, which explains the
enormous diversity that characterizes the biosphere. Clearly, systems ecology has not
developed in a vacuum, but has been largely influenced by the general scientific
development during the last 100 years. A summary of a general ecosystem theory is
presented here. The current proposed theory consists of ten laws.
Autocatalysis in Ecology
In systems ecology, autocatalysis is regarded as a general ized form of mutualism, that is,
an association between organisms of two different species in which each member
benefits. In systems ecology focus remains more on pro cesses and less on objects. Hence,
an autocatalytic configuration of two or more ecological processes is one in which the
processes can be arrayed in a closed cycle, wherein each process in the cycle facilitates
the next. Without loss of generality, one may focus on a serial, circular conjunction of
three processes – A, B, and C.
Thus, any increase in the rate of process A is likely to induce a corresponding increase in
process B, which in turn elicits an increase in process C, and whence back to A. A didactic
example of autocatalysis in ecology is the community that builds around the aquatic
macro phyte, Utricularia (commonly called Bladderwort). All members of the genus
Utricularia are carnivorous plants. Scattered along its feather like stems and leaves are
small bladders, called utricles . Each utricle has a few hair like triggers at its term inal end,
which, when touched by a feeding microheterotroph, opens the end of the bladder, and
the animal is sucked into the utricle by a negative osmotic pressure that the plant had
maintained inside the bladder.
This feeding upon microheterotrophs helps the Utricularia to grow and increase its
surface area (process A). In nature the surface of Utricularia plants is always host to a film
of diatomaceous algal growth known as periphyton, so that more surface area encourages
the growth of more periphyton (pro cess B). More periphyton in its turn means more food
to support the growth of any number of species of small microheterotrophs (process C).
The autocataly tic cycle is closed when it is noted that a greater density of
microheterotrophs provides more resources for the Utricularia to grow (process A again)
by cap turing and absorbing more abundant zooplankton (Figure 2b). Unlike in chemistry,
the actors in ecology are more complex, malleable entities with capabilities to undergo
small, incremental alterations. Such malleability sub stantially enhances the repertoires
of autocatalysis and enables it to exhibit some very nonmechanical beha viors. This is
especially the case when autocatalysis involves processes that can change in stochastic
and nonpredictable ways. An important characteristic of causal cycles (e.g., autocatalysis)
is that when random events impinge upon them, they usually yield nonran dom results.
This is the consequence of the first and foremost attribute of autocatalysis – its generation
of selection pressure.
To see how autocatalysis generates selection, one begins by considering a small
spontaneous change in process B. If that change either makes B more sensi tive to A or a
more effective catalyst of C, then the transition will receive enhanced stimulus from A. In
the Utricularia example, diatoms that have a higher P/ B ratio and are more palatable to
microheterotrophs would be favored as members of the periphyton com munity.
Conversely, if the change in B makes it either less sensitive to the effects of A or a weaker
catalyst of C, then that perturbation will likely receive dimin ished support from A. Hence,
the response of this causal circuit is decidedly not symmetric, and out of this asymmetry
emerges a direction. This direction is not imparted or cued by any externality; its action
resides wholly within the system. As one might expect from a causal circuit, the resulting
directionality is in
