Stability and changes in complex systems

 

It is often assumed that changes in ecosystems appear gradually and smoothly: the dead sea becomes slowly salter with the evaporation of the water, and the amount of fish in the oceans is diminishing because of extensive fishing. A forest becomes gradually smaller when trees are cut down, and the CO2 level in the atmosphere is increasing in an increasing but smooth way with the burning of fossil fuels.   

There is however more and more proof that a lot of systems can suddenly switch from one state to another. Although such an event is usually triggered by one changed variable, the underlying reason is a loss of resilience. To maintain a stable and sustainable ecosystem it is therefore important to focus on maintaining this resilience or flexibility. 

Examples of systems where such abrupt shifts occur are epileptic seizures, asthma attacks and possibly migraine attack in medicine, and in finance we sometimes see systematic market crashes. In ecosystems these abrupt shifts can occur in fish and wildlife populations, woodlands that suddenly become grasslands or vice-versa. Clear shallow lakes can abruptly become murky. Coral reefs can quickly disappear and even deserts appear and vanish in sudden patterns.[1]

3.1            Examples of changes in complex systems, the risk of a climate flip over.

 

How Caribbean coral reefs can suddenly disappear

Everyone who has had the opportunity to snorkel in the sea around a coral reef (or anyone who watches nature shows on television) knows how divers this ecosystem is. Parrotfish nibble on corrals, a little “Nemo” hides away in anemones and larger fish swim in large schools. Although the system seems stable, it can suddenly shift to another stable state, a state with hardly any fish, dead corrals and blooming algae. This shift has several underlying causes, which make the system vulnerable to the actual triggers of the shift. Intensive land-use causes nutrient-loading which allows algae to grow in higher numbers. This nevertheless does not directly trigger an algae bloom, since intensive fishing also leads to an increased number of sea urchins. These urchins control the algae population, by scraping them of the corrals. However, once a pathogen reduces the number of sea urchins, and herbivorous fish have also been diminished, the corrals can quickly be overgrown with fleshy brown algae. While young algae are easily eaten by urchins and fish, adult algae are far less edible. This makes the switch difficult to reverse, also because the algae prevent the settlement of coral larvae. This scenario occurred in 1983 in the Florida Keys, and the coral reefs are still recovering.

 

Three lessons can be learned from this example:

1. A shift in dominance between two different life forms can result in a shift of a contrasting ecosystem state.

2. The trigger that causes the abrupt shift is usually a random stochastic event, such as the pathogen in the Coral reefs example.

3. Biological, physical and chemical mechanisms are involved in stabilizing feedbacks, which can prevent a sudden shift.

Source: Scheffer et al. (2001)

 

 Societal changes and their tipping points

 

“Whatever the explanation is, adult humans apparently have a tendency to stick to a certain mode of behavior even if it is rationally a bad choice. This lock-in mechanism, caused by apparent self-reinforcing adherence to a mode of behavior, tends to promote inertia, a lack of responsiveness to changes in the environment.”

Source: p.5  marten Scheffer and Frances R. Westley. The Evolutionary Basis of Rigidity: Locks in Cells, Minds and Society.  Ecology and Society 12(2):36

 

Sudden shifts in societies

The theory of Rational choice implicates that a choice should not be made in accordance to the previous investment but by the expected future costs and benefits. Regardless of the theory, people still tend to use the prior investment in the decision process. People stick to the tactics that have invested in in the past, regardless of the current situation or predictions which render the choice irrational. -This Sunk-cost effect is even larger in groups of people, because people in groups usually try to maintain a previously reached consensus. The implications of this irrational behavior is that groups stay longer than necessary in unfavourable situations, this has even led in the past to collapses of whole societies.[2]

 

There are several historical examples of sunk costs situations in societies. Around the 15th century, Norwegians on Greenland were faced with a sudden period of extreme cold. Because of this, the harvests of their crops became increasingly less productive and they became more and more undernourished. Still, they stuck to their known agriculture techniques instead of adapting to their neighbor’s Inuit skills who were well fed because of their fishing and hunting methods. The Norwegians did not survive, the whole colony died from famine. Another famous example are the Meso-American societies who built enormous temples which can still be admired today. These enormous structures were one of the reasons why the Mayas who lived there felt unable to quickly leave in times of severe drought, leading to their decline.

In recent history there is the example of the supersonic passenger plane, the Concorde. Before the completion of the airplane it was already clear that it would be very unlikely to make a profit with the project. But because there was so much money invested, the UK and France did not want to pull the plug.[3] Today we see the same with large building projects and the military F-35 Program, better known as the Joint Strike Fighter (JSF): the costs have risen extremely, and there are several better and cheaper alternatives available.

 

At this moment there is still not an immediate societal problem that mobilizes a large part of the population. Because of the relatively low oil prices, alternatives are comparatively expensive, making it difficult for consumers and investors alike to move away from fossil reserves. The energy related CO2 emissions have become stabilized over the last two years (2014 and 2015), while the world’s economy was growing, for the first time in 40 years.[4]

As long as there still is cheap oil available, the most distinct problems for which the BBE is a solution (unavailability of energy and resources)might be  too abstract for a lot of people. At the same time, there is a moral duty to abstain society from these problems, therefore action must be taken before the challenges are directly tangible. One of the ways to involve people in an earlier stage is through the production of social representations and public engagement. For example by organizing small biobased projects such as a community dinner, where all elements are made with biobased materials, including the plates and menus.[5] Another way of involving a larger part of society is by not communicating technological changes  “towards” people, but to communicate with them in an early technological phase.

In this conference talk, Marten Scheffer explains how changes in complex systems are characterized by tipping points. In the last 5 minutes he also describes changes in society:

 

According to Jan Rotmans who is professor in transitions and sustainability, we are currently in a state of transformative change. Because we are  experiencing a system crisis, we need to transform ourselves and our society in a bottom-up way. One of the ways that this can be done is by the emerging power of the Do It Yourself (DIY) society. New jobs: “roofdoctors”, gardeners who are gardening on the roofs. Organic governance, moving with the transformative times. In this TEDx video he explains his ideas:

 

 

 

[1] Marten Scheffer et al. (2009)

[2] Janssen et al. (2003)

[3] This even led to the name “The Concorde effect” for sunk costs situations  (Dawkins and Carlisle 1976)

[4]See  https://www.iea.org/newsroomandevents/pressreleases/2016/march/decoupling-of-global-emissions-and-economic-growth-confirmed.html

[5] See Sleenhoff et al. 2015, p81