Reading 3.5: Interdependence
The first step in transforming the way you think involves coming to terms with the fact that you are not an independent, isolated object, but rely on flows of energy, matter and information from living and non-living systems that surround you. You in turn, contribute to these systems in ways which can be mutually beneficial or destructive.
A fascinating aspect of living systems is their interdependence. This can be interdependence between organisms, at its closest 'symbiosis' where two different organisms live in physical contact helping each other; for example the fungi which live in the root systems of trees. Any ecosystem consists of a group of interdependent organisms. Interdependence can also be across different levels of organisation: a cell which is part of an animal's liver cannot survive within a failing organism, and of course neither can the liver; an individual cannot survive within a disintegrating ecosystem; and we are now seeing ecosystems disappearing with the disruptions happening partly due to global warming and human interference. The Earth is made up of a nested hierarchy of living systems, all demonstrating tight chains of interdependence both within individual systems and across these levels.
In his 1979 book, Gaia – a New Look at Life on Earth, James Lovelock (Lovelock, 1979) proposed that even Earth demonstrated self-regulating (homeostatic) behaviour (Figure 3.3). The biosphere, which represents the thin layer of life on Earth mostly concentrated below 6000 m above sea level and above 1000 m below sea level, is hypothesised to regulate global temperatures and chemical composition so as to create optimal conditions for life. For example, since its formation 4.57 billion years ago, the Sun has been emitting increasing quantities of radiation, mostly as high-frequency light waves. On Earth, these light waves are eventually transformed into heat. The increasing intensity of light would eventually make conditions too hot for life. Fortunately, higher light intensities promote the growth of phytoplankton in the oceans. Phytoplankton emit dimethyl sulfide gas as a waste product, and this makes its way to the upper atmosphere where it acts as a strong catalyst for the creation of clouds. The clouds in turn act as a barrier against the sunlight, and are able to reflect most of it back into space. Thus, phytoplankton, through their effects on cloud formation, act as a key element in the regulation of the Earth's temperature, because the higher the light intensity, the more phytoplankton grow, and the more cooling effect their emissions have.
But what does this interdependence between nested systems consist of? All living systems can be defined as open systems – they all depend on flows of energy, matter and information, to maintain their structures and functions. Thus, higher-level systems organise the flow of energy, matter and information through lower-level systems.
Our bodies make sure that each one of our cells is supplied with calories to fuel metabolism, proteins and other molecules to serve as building blocks, and hormones to increase or decrease the production of certain chemicals. In turn, the social-ecological system within which we live organises our daily activities so that we can meet the needs of our bodies. Our social-ecological systems are in turn adapted to the local ecosystems within which they are nested. To use a trivial example, the longest school holidays in the northern hemisphere are usually during the hottest months of June to August. In the southern hemisphere, December to February is the preferred break period, and this tradition can be traced to the need to release children to help with the harvest.
In their 1990 report to the Trilateral Commission (a non-governmental organisation promoting the debate of cross-cutting international issues), Jim MacNeill, Pieter Winsemius and Taizo Yakushiji stated:
Since World War II, governments have been preoccupied with economic interdependence, the coupling of local and national economies in a global system. But the world has now moved beyond economic interdependence to ecological interdependence – and even beyond that to an intermeshing of the two. The Earth's signals are unmistakable. Global warming is a form of feedback from the Earth's ecological system to the world's economic system. So is the ozone hole, acid rain in Europe, soil degradation in Africa and Australia, deforestation and species loss in the Amazon. To ignore one system today is to jeopardise the others. The world's economy and the Earth's ecology are now interlocked – 'until death do them part,' to quote one of Canada's industrial leaders. This is the new reality of the century, with profound implications for the shape of our institutions of governance, national and international. It raises fundamental questions about how economic and political decisions are made, and their implications for sustainability.
(MacNeill et al., 1990)