The attitude we think it appropriate to take toward living things depends on how we conceive of them and of our relationship to them. What moral significance the natural world has for us depends on the way we look at the whole system of nature's production and our role in it. With regard to the attitude of respect for nature, the belief-system that renders it intelligible and on which it depends for its justifiability is the biocentric outlook. This outlook underlies and supports the attitude of respect for nature in the following sense. Unless we grasp what it means to accept that belief-system and so view the natural order from its perspective, we cannot see the point of taking the attitude of respect. But once we do grasp it and shape our world outlook in accordance with it, we immediately understand how and why a person would adopt that attitude as the only appropriate one to have toward nature. Thus the biocentric outlook provides the explanatory and justificatory background that makes sense of and gives point to a person's taking the attitude.
The beliefs that form the core of the biocentric outlook are four in number:
To accept all four of these beliefs is to have a coherent outlook on the natural world and the place of humans in it. It is to take a certain perspective on human life and to conceive of the relation between human and other forms of life in a certain way. Given this world view, the attitude of respect is then seen to be the only suitable, fitting, or appropriate moral attitude to take toward the natural world and its living inhabitants.
If we now ask, "Why should moral agents accept the four beliefs that make up the biocentric outlook?" the answer lies in showing that, to the extent that moral agents are rational, factually informed, and have developed a high level of reality-awareness, they will find those beliefs acceptable. The acceptability of the beliefs is linked with the rationality, factual enlightenment, and reality- awareness of moral agents in such a way that moral agents who have those properties accept the beliefs because they are rational, informed, and aware of reality.
The academic structure for ecology, as a new science was established by geographers. The prominence of the discipline of geography in the nineteenth century, its contributions to other sciences, and its widespread interest for the general reader are seldom appreciated today. But geography in that period was a powerful cultural force; Humboldt, Lyell, and Darwin are only the most famous of its students. Strictly speaking, however, it was an aberrant group among geographers who first attempted to describe the topography of living things.
Throughout most of the nineteenth century, as today, the most familiar school of biogeography was the study of flora and fauna. Essentially this was a matter of compiling statistical data on the distribution of species around the world and then deriving from such data a system for classifying geographic regions. The floristic geographer was bound to be interested in the adaptations of organisms to their environments, a process that Haeckel included in the territory of ecology. But this interest was limited; the controlling purpose of the dominant school was taxonomic more than ecological. To reverse this order of priorities was precisely the intention of the lesser-known, rival school, which was at first known as "physiognomic," then "physiological," and finally as "ecological" geography. This school preferred to talk about the forms of "vegetation" and their determinants rather than about the distribution of the earth's plant species.
The variety of life is an expression of geography. Geographical ranges of species vary in size from a few square metres to almost the entire globe. Geographical boundaries, beween species are determined by the local solar economy and the planetary; i.e. effects of climate and seasons and the effects of geomorphological events in Earth's history.
These two energy economies define local biogeographical systems which determine the evolution of species and the diversity of communities.
Biodiversity is now declining through the impact of human production systems. 'Conservation' is the local response to preserve and enhance geographical variety amongst living things.