7. A transition framework
This Section introduces a conceptual framework designed to encourage and facilitate thinking and communicating about the implications of different options for the future for the full spectrum of ecological and health issues. It recognises the crucial role of culture in determining the health both of humans and of the ecosystems on which they depend, and it is based on biohistorical principles which have been discussed in a number of publications.
Our starting point in constructing the framework is the Biosensitivity triangle that was introduced in Section 3 of this collection.
The transition framework is explained below and depicted in Figure 2. 
Human health needs (Box 9) and Ecosystem health needs (Box 10)
In the biosensitivity triangle (Figure 1, above) the two boxes on the right hand side are Healthy people and Healthy ecosystems, which are our ultimate goals in planning for a biosensitive future. However, from the planner’s standpoint what is actually more relevant are the immediate requirements for health (e.g. clean air and water for human health; and maintaining biodiversity and soil fertility for ecosystem health). These health requirements are called ‘health needs’ in the framework (Figure 2, above).
Options for the future must be assessed ultimately in terms of their impacts on these health needs.
Biophysical environment (Boxes 7 and 8)
This set of factors has been inserted into the triangle because the impacts of human activities on the health needs of people and ecosystems are sometimes indirect, in that the ultimate effect on health is the result of changes brought about in the biophysical environment.
For example, the human activities that result in the release into the environment of CFCs lead to chemical reactions in the atmosphere and the destruction of ozone in the stratosphere. This change in turn results in an increase in the ultraviolet radiation at the Earth’s surface (Box 7), which interferes with the health both of ecosystems and of humans.
Another example is provided by cases when the application of artificial fertilisers to farmland leads to eutrophication in creeks and rivers. The consequent excessive growth of algae results in anoxia in the aquatic ecosystem and then to loss of biodiversity and also to the production of toxins which can cause illness, even death, in humans and other large mammals.
On the other hand, of course, many undesirable impacts of human activities on human and ecosystem health are direct - such as the effects of tobacco smoking on human health and the effects of oil spills on local fauna.
Recognising the crucial role of culture in determining the health both of humans and of the ecosystems on which they depend, ‘Biosensitive society’ in Figure 1 has, in Figure 2, been divided into two categories: Biophysical options (Boxes 3-6) and Cultural options (Boxes 1 and 2).
Biophysical options (Boxes 3-6)
Biophysical options include the biological and physical aspects of human situations that can be influenced by people’s decisions and that directly or indirectly affect the all-important health needs of humans and of ecosystems (Boxes 9 and 10).
Biophysical options are subdivided into 4 sub-categories:
- Human population (Box 3) - such as numbers of people, population density, population age structure
- Human activities - collective (Box 4) - such as manufacturing, farming, military activities and transport.
- Human activities - individual (Box 5) - such as lifestyle options, travel patterns, physical exercise and consumer behaviour
- Artefacts  (Box 6) - such as buildings, roads, machines, vehicles and furniture.
Cultural options (Boxes 1 and 2)
Human activities are to a large extent governed by Societal arrangements (Box 2), such as the prevailing economic system, governmental regulations and the institutional structure of society.
These societal arrangements are in turn to a large extent determined by the worldview, assumptions and priorities of the dominant Culture (Box 1).
For example, the cultural assumption that the best thing for our society is continuing economic growth involving ever-increasing use of resources and energy (Box 1) is a major force affecting the economic system and governmental policies (Box 2), and consequently patterns of human activity (Boxes 4 and 5), and so ultimately the health of our planet’s ecosystems (Box 10).
Table 3 lists some examples of important factors – biophysical and cultural – that need to be taken into account in assessing options for the future.
Making use of the framework
From the practical point of view an important use of the framework is as starting point for constructing a check list of the essential characteristics of a biosensitive society. This we have attempted to do in Section 3 of this document.
It is to be hoped that the day will come when biosensitivity check lists are routinely used at all levels of government to guarantee that, whenever an important policy decision is considered, it will be assessed in terms of its likely impacts on both human and ecosystem health. Some of the implications of this conclusion for government policies are discussed above in Section 3 Biosensitivity - a vision for the future under the heading ‘Societal arrangements’.
Take for example urban planning. Recognising that the ultimate objective of such planning is healthy people and a healthy natural environment, the biosensitivity check list and framework can used as a basis for putting together a list of essential objectives to be borne in mind in planning for a healthy and ecologically sustainable city (see Table 4)
Turning to the lifestyle choices at the level of individuals – again the biosensitivity framework and check list are useful – recognising that lifestyles should not only satisfy the individual’s personal health needs, but that they should also be consistent with the health of the natural environment (see check list under the heading Human activities – Individual in Section 3 above).
Human health needs 
Table 2 (Box 10)
The health needs of ecosystems
In light of our knowledge of the effects of various human activities on ecosystem health at the present time, we can put together a check list of ecosystem health needs, as follows:
|Human cultural options||Human biophysical options|
Dominant culture (Box 1)
Human population (Box 3)
Human activities – collective (Box 4)
Use of fossil fuels (and other energy sources)
Human activities – individual (Box 5)
Artefacts (Box 6)
Layout of roads and cycle tracks
Table 4: Planning for biosensitive cities
A check list of essential objectives to be borne in mind by contemporary town planners
Energy use and electricity generation
1. See, for example, S. Boyden, 1987 Western civilization in biological perspective: patterns in biohistory. Oxford University Press. Oxford, and S. Boyden. 2004 Back to text
2. The fact that some of the arrows in this diagram are pointing only in one direction demands an explanation. It does not mean, of course, that there are no important feed-back loops in the system. However, this is not a ‘systems diagram’. The direction of the arrows simply reflects our chief interest – namely, the important factors and pathways of influence, direct and indirect, on the health of humans and ecosystems. Back to text
3. Artefacts is used to mean ‘things made by humans’. Back to text
4. This working list of human health needs is based on the evolutionary health principle and our knowledge of the conditions of life in the long natural, or hunter-gatherer phase of human existence. Back to text